Varyag (1899)

Protected Cruiser Varyag (1899)

Russian Empire 1898-1925

The ship with six lives*

The Russian cruiser Varyag was a ship that was commissioned in 1901 and played an important role in the Russo-Japanese War. The Varyag was part of the Russian Pacific Fleet, and was stationed in the port of Port Arthur in Manchuria when war broke out.
On February 8, 1904, a Japanese fleet attempted to blockade the port, and the Varyag was ordered to break through the blockade and attempt to make it to the safety of the Russian port of Vladivostok. Despite being heavily outnumbered and outgunned, the Varyag fought bravely, inflicting significant damage on the Japanese fleet before finally being forced to scuttle itself to prevent capture.
The story of the Varyag became a symbol of Russian bravery and resilience in the face of overwhelming odds, and the ship itself became a legendary figure in Russian naval history. The wreck of the Varyag was eventually salvaged and its bell is now on display at the Central Naval Museum in Saint Petersburg.
*(US Built, Imperial Russian(i), Imperial Japanese, Imperial Russian(ii), “Red” Russian, British).


Varyag in Kronstadt, 1905

Design of the class

Origins and development


On Brassey’s naval annual 1900

In 1895 after the 1st Sino-Japanese war won by the latter, western powers made a triple intervention to force the rather harsh treaty of Shiminoseki and in 1898, Russia signed a 25-year lease on the Liaodong Peninsula, proceeding to set up a naval station at Port Arthur. This enabled the possibility of a pacific fleet, for which there was no ship available yet. A large naval expansion program was decided, which comprised cruisers and soon battleships. All cruisers were designed with the same capabilities in mind.
According to the Russian Admiralty, one of the new cruisers needed was designed to be a fast and well protected, capable of long-range operations, armed with a variety of weapons to be self-sufficient: Artillery of all calibers, torpedoes and mines as well. This was formulated in 1897 by the Russian Admiralty, and this called for a fast protected cruiser capable of commerce raiding.

There were associated requirements, having 152 mm (6-inch) quick-firing guns, and a 23–24 kn (43–44 km/h; 26–28 mph) top speed. But at the time, Russian yards were already at full capacity and unable to deliver, therefore the idea soon emerged of a foreign purchase, but there was no time for international request for proposals. The commission just looked after the ideal yard.
On 11 April 1898 and order for a single cruiser based on this specification was submitted to Cramp and accepted. Other cruisers at the same time were asked to Germaniawerft for Askold, AG Vulcan for Bogatyr based on the very same specifications. This would lead the admiralty to do also comparative tests.


Jane’s fighting ghips rendition in 1899, left elevation

The US yard Cramp Shipbuilding, William Cramp & Sons Shipbuilding Company or William Cramp & Sons Ship & Engine Building Company of Philadelphia (founded 1830) and renown as the most preeminent U.S. iron shipbuilder of the late 19th century was not chosen at random. It proposed a tailored design, which also had some consequences on USN own cruiser designs. Apart Trans-Atlantic liners, the company also signed the USS Baltimore (C-3) in 1888 USS New York in 1891, USS Indiana (BB-1), or USS Iowa (BB-4) in 1896. Varyag was completely different that usual US cruisers designs, and could not be compared to the “masted commerce raiders” built up to that point. They also digested lessons from the 1898 war, something that also drawn the attention of the Russian commission.

Eventually Varyag was laid down in October 1898 and launched on 31 October 1899, one of the fastest cruiser built in the world at the time, but commissioned into the Imperial Russian Navy on 2 January 1901. Her first captain was Vladimir Behr.
As for the usual crunchy anecdote, during construction, an assistant physician, Leo Alexandroff, deserted the advanced sailors party on 20 April 1899 and applied for U.S. citizenship. He was arrested for desertion, but his case reached the US Supreme Court, which ruled that the ship was still not accepted for service when in happened and under the terms of the 1832 treaty between Russia and the United States, still nominally in US possession via its shipyard, so under the yard’s staff authority. In short, she was still “possessed” by the US, hence her six lives (US, Russian, Japanese, Russian imperial/bolshevik and British). Nevertheless, Alexandroff was returned to Russian authorities.

Hull and general design


Varyag was a 6040 tons standard, 6,500 tons fully loaded ship, 129.56 m long by 15.9 m (in beam without plating) and with a mean draft of 5.94 m* midships. According to US practice she had a tall freeboard, with a nearly four deck high forecastle and two deck high aft hull. She had a good ratio for speed, 1/9, and good seakeeping. Her silhouette as typical of both US and Russian cruisers of the time, with a forward bridge tower built above the conning tower (which was rather large and three stages high), top open bridge with chadburn and voice pipes, and wings with communication lights, followed by fore military mast carrying a fighting top and above a platform for the forward projector. The hull ended forward with a reasonably bulging ram bow and reinforced prow.

Like the mainmast aft, in front of the small lattice aft platform carrying projectors and guns, it was a single tubular and upwards decreasing steel piece. Amidship were located five tall and heavenly spaced funnels, composed of two-parts. They were tall enough to not smoke over the spotting tops. This central part was dotted with cowl vents and locations of boats. The three main coal barges, steam cutters and whalers were planed on davits, three per side. The four outer ones were pinnaces and yawls, two close to the bridge and two aft abreast the mainmast.
The Crew comprised 20 officers, 550 sailors and non-commissioned officers. It was planned to use the steam pinnaces to carry landing parties off-shore and dismountable small arms could be added as support (see below).

Armour protection layout

As a protected cruiser, Varyag had the “usual panoply” combining a turtledeck above the steering, machinery spaces and ammunitions rooms, combined with a belt along the waterline. The conning tower was the only upper protected part. No guns had shields. This Armor deck comprised several thicknesses depending of the angle and locations, ranging from 38 mm (horizontal section) to 57 mm and 76 mm (3 inches) on the slopes. The armor belt was in fact internal and sloped as part of the final section of the armor deck. The large conning tower was the best protected part of the ship with walls 152 mm (6 in) thick, weighting 588 tons alone. It comprised an upper bridge command deck pierced with loopholes for peripheral vision, and a map deck below.
There was also 38 mm (1+1⁄2 in) of armour protecting the ammunition hoists, and 76 mm (3 in) protecting the bow and stern torpedo tubes.

Powerplant

Two shafts, with three-bladed bronze propellers connected via shafts to two Cramp steam Engines of the vertical triple expansion type, fed in turn by 30 Niclausse steam boilers (Russified as “Nikloss”) for a total output of 16,198 shp, for a top speed of 23.2 knots, 20.5 knots however in 1905, and 16 knots cruise speed, and a cruising range at 10-knot of 6,100 miles (with full supply of coal) down to 3,270 miles with the normal coal supply load.

Armament

Main

The ship was delivered unarmed. Her main armament comprised twelve Obukhoff 152 mm (6-inch) L/45 guns: Two guns side by side on the forecastle, two side-by-side on the quarterdeck. The remaining eight were on sponsons on the upper deck. None was protected, unliked what it is shown on Jane’s. They fired a 50 kg (110 lb) shell at 9,800 m (10,700 yd) with a rate of fire of 6 rounds per minute. In all, the ship carried total 2,388 rounds main ammunition, both HE and AP. More

Secondary

Varyag also had twelve 75 mm (2.95 in) L/50 QF guns for anti-torpedo boat warfare. They were located alongside the battery deck amidship and in hull casemates.
They could could fire a 6 kg (13 lb) HE shell to 7,000 m (23,000 ft) at 10 rounds per minute.
This was completed by eight Hotchkiss 47 mm revolving cannon, with two on each fighting top, four more on the upper deck.
This was completed by two 37 mm (Hotchkiss ?) revolving guns and two Maxim machine guns but also two dismountable Baranowski 64 mm landing guns (on wheeled carriages, fitted on pintles forward of the steam pinnaces) also carried for landing parties.

Torpedoes and Mines

Varyag was fitted with six 381 mm (15 inch) torpedo tubes, two on each broadside, one in the bow and stern each. They were likely the standard Howell 15-in type of the day, or possibly Whitehead-Fiume type. As for mines, it was at first planned, but no railings was ever installed as shown on plans.

⚙ specifications

Displacement 6,500 long tons (6,604 t)
Dimensions 129.6 x 15.8 x 6.3 m (425 ft 2 in x 51 ft 10 in x 20 ft 8 in)
Propulsion 2 shafts VTE, 30 Niclausse boilers 20,000 ihp (15,000 kW)
Speed 23 knots (43 km/h; 26 mph)
Range 6,100 miles
Armament 12× 152mm, 12× 75mm, 8× 47mm, 2× 37 mm, 6× 381 mm TTs
Protection See notes
Crew 570

Read More

Books

Buxton, Ian (2001). “Question 36/99: Imperial Russian Cruiser Variag”. Warship International. XXXVIII
Campbell, N. J. M. (1979). “Russia”. Conway’s All the World’s Fighting Ships 1860–1905.
Kowner, Rotem (2006). “Historical Dictionary of the Russo-Japanese War”. Scarecrow.
Smigielski, Adam (1979). “Imperial Russian Cruiser Varyag”. In Roberts, John (ed.). Warship Volume III. Conway
Wetherhorn, Aryeh (2001). “Question 36/99: Imperial Russian Cruiser Variag”. Warship International.

Links

Full Plans from shipmodell.de
On ru.wikipedia.org
en.wikipedia.org
Japanese_cruiser_Soya wiki
On tsushima.su
http://sic-transit.ru/
commons.wikimedia.org/wiki/Category:Varyag_
zn.ua/
https://sergeyurich.livejournal.com/
On youtube

Model Kits


Zvezda 1:350 old kit on scalemates.com/ The full lists includes a Limited Edition (Full Model kit w/Deck & Detail-up Parts) by ArtwoxModel 1:350 AA10001 2012, Zvezda 1:350 9014 2010 kit, and 2003 New toolling kit, Combrig 1:700 70133 Mks R-005 and by Modelkrak 1:700.

Early Career of Varyag (1901-1905)


Captain Rudnev and Varyag as completed
Varyag (her name referred to the Byzantine “Varangian Guard”) after commision in the US, Philadelphia, on 2 January 1901, spent the first years in training, 1901, 1902 and 1903 in the Baltic before departing for the far east. From the beginning of January 1904, with arrived at the neutral Korean port of Chemulpo, at the disposal of the Russian embassy in Seoul, in presence of other ships from England, France, USA and Italy.
On February 8, 1904, the Japanese squadron (Asama and Chiyoda, Naniwa, Niitaka, Takachiho, Akashi and 8 destroyers) blocked Chemulpo to cover the landing and prevent Varyag to intervene. The same day, there was a sortie from to Port Arthur but upon leaving the port, the relief fleet was attacked by IJN destroyers which two fired self-propelled mines and missed, after which they fold back. The Japanese landing of 2,000 troops was not interfered with.

On February 9 Varyag’s captain Vsevolod Fedorovich Rudnev received an ultimatum from the squadron’s admiral: Leave the port of Chemulpo before 12 o’clock, or be attacked in the roadstead. Rudnev decided to break through and fight his way to Port Arthur, and scuttle his ship if failing to do so. At noon, Variag and the gunboat Korietz left Chemulpo and saw the Japanese squadron behind the island of Phamildo.

The Battle of Chemulpo Bay: Varyag felt the weight of Admiral Uriu’s squadron of six cruisers and tried a heroic gamble, counting on his speed and firepower. His break out attempt from Chemulpo (Incheon) started on 9 February 1904. As promised, he put up quite a fight. For an hour, Varyag manoeuvered well to try and dodge enemy volleys while firing 1,105 shells at the enemy, and the gunboat Korietz 52, although it could have been well overestimated. The Gunboat later blanketed both with a smoke screen for added protection. So that they could leap frog in and out of this cover while firing. According to Rudnev, his cruiser sank one destroyer and damaged IJN Asama, the armoured flagship, as well as the older Chiyoda. Official Japanese sources never confirmed this.

Anyway, his ship suffered numerous hit, and he lost 31 men, with 191 injured; He eventually decided to return to the harbor for repairs, counting at 1:00 p.m. the neutrality to apply.
His damage as reported were the broken rangefinder station number 1, 6-inch guns No. 3, IX, XII, 75-mm gun No. 21, 47-mm guns No. 27 and No. 28 were knocked out, rangefinder station No. 2 destroyed, guns No. 31 and No. 32 were blow away, all 47-mm guns damaged by shrapnels, five 6-inch guns damaged, seven 75-mm guns damaged, steering gears pipe broken, four underwater holes, upper funnel shattered, all fans broken, commander’s quarters destroyed. Rangefinder officer Count Nirod and 38 lower ranks were killed, 3 officers wounded like midshipman Gubonin, Laboda and Balk as well as 70 lower ranks. Captain Rudnev himself was shell-shocked and received a head wound. After the battle, 24 wounded Russian sailors were treated in Chemulpo, but two died. Another 11 were treated aboard foreign ships present.


A disabled Soya in Chemulpo

The crew decided not to surrender but to sink their ship. They were evacuated onto the British cruiser Talbot, French cruiser Pascal, Italian cruiser Elba but this was protested by US gunboat Vicksburg’s captain, which dedided against taking these crews onboard due to U.S. neutrality. A preliminary agreement was reached before the scuttling of the Varyag, assorted with an obligation not to take part in subsequent hostilities and return to Russia through neutral ports.
On March 19, 1904, the first group of 300 arrived in Odessa on the steamer Malaya, and the third and last group arrived on April 6. In total, 30 officers and 600 sailors as well as from the gunboat, and 55 sailors from the Sevastopol plus 30 Cossacks of the Trans-Baikal Cossack Division in Seoul arrived by ship to Odessa. From there they proceeded to Sevastopol, and to St. Petersburg, through Simferopol.


Crew ceremony in 1904

On April 16, 1904, sailors and officers arrived in St. Petersburg as heroes and lining up in columns, they marched from the Nikolayevsky railway station to the Winter Palace Square, greeted by Emperor Nicholas II, later invited to a gala dinner at the palace for the celebration of their “last stand”. All sailors were also gifted personalized watches by the Tsar. In 1907, Vsevolod Rudnev, promoted to rear admiral, was decorated with the Japanese Order of the Rising Sun for his heroism in that battle, at the Japanese Embassy. This was a unique honor made by the Japanese to a foreign officer. It was accepted, but never wore in public. There was a stele erected also by the Japanese in Seoul in memory of the Varyag.

As IJN Soya (1907-1916)


IJN Soya as colorized by Irootoko Jr. Photographed during one of her trips to Australia.

After the Russo-Japanese War, Varyag was raised on August 8, 1905 from Chemulpo harbor and repaired by Japan, arriving on the 22th. With modifications to IJN standard she was commissioned as the 2nd class cruiser “Soya” (Jap. 宗谷 after the Japanese name of the northernmost cape of Hokkaido, Cape Soya Misaki) on 9 July 1907. After trials and initial training, she was re-rated as a 3rd class cruiser and used for training. From 14 March 1909 to 7 August 1909, she made navigational and officer cadet cruises, notably to Hawaii and North America, even stopping at Cramp. These training cruises went on yearly until 1913.


The same original photo

For more than seven years it was used by the Japanese for training, but as a tribute to her past career, the name “Varyag” was left on the stern by personal decision of Emperor Mutsuhito. From March 14 to August 7, 1909 Soya went to the Hawaiian Islands and North America for long distance navigation and train officers. On December 1, 1915 she made her last long cruise.
Indeed after 1914, Russia at war badly needed ships, and now both Empires being again united, had the Tsar’s government demanding Tokyo to send them back IJN Soya along with several other vessels, to be transferred at Vladivostok, on 5 April 1916. She was of course renamed Varyag upon delivery. During the First World War, the Russian Empire and Japan became allies. Soya together with the battleships Sagami and Tango were bought back by Russia. On April 4, the Japanese flag was lowered and on April 5, 1916, the cruiser was officially renamed as “Varyag”, reassigned in the Arctic flotilla, and prepared to start her long trip back home.


Stern view of IJN Soya

Late career of Varyag (1916-1918)

After changing colors, Varyag proceeded to the baltic, a reverse of the baltic fleet long voyage undertook to the far east in 1905. In June 1916, she departed for Murmansk, via the Indian Ocean through November 1916 and arrived in Liverpool for recoaling and an overhaul at Cammell Laird, in February 1917. She was set to resume service in the Arctic squadron when the Revolution broke out on 7 November 1917. Some informed Russian crewmen, despite their officers ademonestations, hoisted the red flag and refused to obey orders. The situation became quite tense for the British Government, which sent warships and troops to deal with the issue. Eventually on 8 December 1917 she was seized by force, with a detachment of British soldiers.


IJN Soya wrecked in the forth of forth

Later she was confiscated since the Soviet government refused to pay the Russian Empire debts. Provisionally assigned to the Royal Navy in February 1918 (she changed hands a 5th time, the “reds” was the 4th…). In 1920, she was resold to a German shipbreaker. But the proud vessel refused her fate and while under tow, she met a storm and ran aground off the western coast of Scotland, near Lendalfoot, Firth of Clyde, Irish Sea. Since 1923, she stayed there until, pillaged, and later local companies removed part of her metal structures. What left sank. Later she was blown up and the remaining scrap metal was salvaged. Nothing is left of her but her flag (and bell), now at St Petersburgh and presented for great occasions. The 1980s Slava-class heavy cruiser “Varyag” perpetuated the tradition.

WW2 Imperial Japanese Cruisers

Imperial Japanese Navy Cruisers of WW2

The fleet’s spearhead

In December 1941, the most valuable asset of the Imperial Japanese Navy, after the aircraft carriers of the combined 1st air force (Kido Butai), were its Cruisers. Indeed, contrary to the older, slower battleships, cruisers were built along along the interwar and perfected until stopped during the war itself, when fewer resources were available.

All in all, despite having formidable offensive assets, IJN cruisers performed actions in dispersed order depending of their age and capabilities. The real spearheading ones were only twelve: The four Myoko, the four Takao and the four Mogami. They were the most recent, best armed, largest of the IJN and indeed took part in the most offensive fleet units of WW2 in the Pacific.

The older 1920s vessels of the Tenryū, Kuma, Nagara and Sendai classes were stil transitional WWI designs which were arguably obsolete in 1941 and were sent to aid eny convoy which needed protection; thus logically sidelined and never used in first line units. The experimental Yubari followed that path, but the more potent Furutaka and Aoba classes at least saw more frontline action. Wartime vessels such as the Tone were in effect the last “heavies”, joining the pack, but the four Katori were essentially schoolship with little military value, and the four Agano were rather more escorts than frontline cruisers.

Special mention to the never-built B-64 though. These “large cruisers” to keep the US denomination adopted for their Alaska class, proven to be an imaginary threat were indeed planned by the IJN high command planning the end of peactime limitation, as a “cruiser hunter”.

Legacy: WW1 cruisers still in service

In December 1941 there were still a surprising number of WW1 vessels still listed as active, dating back from before the great war. On paper, this was even impressive and only comparable to the Royal navy’s C and D class cruisers. There were of course those of the 1918 plan which were the best known, the oldest of which being the two Tenryu class launched in 1918, but the following Kuma and Nagara (11 cruisers) designed as destroyers leaders were completed at the time the Washington treaty was signed. They are seen in the later part of this article;
As for older cruisers, the list was comprehensive, but the Washington treaty forced their scrapping and/or conversion to other roles. Not willing to scrap what for them was perfectly valid ships, paid a high price compared to the country’s GDP, they were maintained in service by using the exemptions of the treaty: Training and Miscellaneous ships (like minelayers).
And thus a remarkable number of these “antiques” in 1942 were still proudly flying the hinomaru.

Battlecruisers:

If the four Kongo class were the last and best known, reconstructed twice in the interwar and gradually converted as fast battleships and thus not counted here. The older Kasuga class, Ikoma and Kurama class were classed as armoured cruisers (from 1921 for the latter).

Armoured Cruisers:

Asama class: Launched 1898, Asama was converted as a training ship in 1937 (BU 1947) and Tokiwa as a minelayer by 1928.
Yakumo: Launched 1899, she became a coast defence ship (full detail later)
Adzuma: Launched 1899, was also converted as a coast defence ship, and doubled as trainign ship as Yakumo.
Izumo class: Izumo and Yakumo, Launched 1900 were 9750t ships with the same status: TS in peacetime, coast defence ship in wartime.
Kasuga class: Kasuga and Nisshin were “1st rate cruisers” and used as training ships from 1927 as new vessels took their place. Nisshin was expended as target in 1936 but Kasuga only retired in 1942. She was sunk in Kure the same day as the two Izumo in July 1945 (see later).
Kurama class: The former battlecruisers, reclassed in 1921 as “1st rate cruisers” were considered during the Washington treaty too valuable to keep even as training ships. They were ordered to be scrapped, which was done in 1923, to quite some frustration from the naval staff.


The IJN Yubari (here colorized by irootoko Jr) at Sasebo just completed in 1923. This strange prototype light cruiser marked the rebirth of the IJN after the Washington treaty. She really was built not to fill a precise requirement (but of a fleet scout), but merely to test new weight-saving construction techniques will would allow the IJN naval staff to get “more with less”, doing better than the (US-British) competition in armament on smaller tonnages. The Tomozuru and 4th fleet incidents would shatter these illusions.

Protected Cruisers:

Smaller and of an earlier design these vessels were improper for training ship conversion. Re-rated as 2nd class cruisers in 1921, their career was shortened, except for three.
Chitose class: This 4760t, 1898 ship was discarded in 1928, sunk as target 1931
Niitaka class: Niitaka and Tokiwa were 1902, 3,366 tons cruisers no longer active: The first was lost in a typhoon in 1922 and the second hulked in 1930, sunk in 1944.
Tone: This 1904 4,100 ton cruiser was discarded in 1931, sunk as target in 1933.
Chikuma class:
These had a more interesting career. Still “young” in 1922, they were reboilered and rearmed to extend their useful life. Chikuma due to tonnage limits was discarded in 1931, Hirado in 1939 and Yahagi hulked in 1940 so they took no part in the hostilities, but both survived WW2 nevertheless.

Postwar cruiser development: Yuzuru Hiraga’s design school

hiraga Baron Yuzuru Hiraga was one of the most influential (if not the most) of the Imperial Japanese Navy in the interwar. Born in Tokyo, grewing up in Yokosuka, Kanagawa (his family was from Hiroshima) he graduated from Hibiya High School and was in the engineering department of the Tokyo Imperial Universityby 1898. As specialist in marine engineering. Draft in the IJN while still being a studen in 1899 he graduated in 1901 as sub-lieutenant and started working at the Yokosuka Naval Arsenal a design engineer.

A lieutenant on 28 September 1903 she was transferred to Kure Naval Arsenal in 1905 just as the Russo-Japanese War started. He was soon sent to the allied United Kingdom for extra studies of British designs, leaving Yokohama for the Pacific in January and also visiting the United States west to east, and crossing the Atlantic Ocean to London in April 1905. By October, he became a member of the Royal Naval College in Greenwich, having the most immediate immersion into the latest techniques in warship design. Graduated from there by June 1908 he spent six months touring various shipyards in France and Italy for an extra insight,nwriting many reports befire arriving in 1908 back in Japan. By September her became professor of engineering, at Tokyo Imperial University, promoted to lieutenant-commander on 1 October.

In 1912 he was part of the design team in charge of the design for the battleship Yamashiro (Fuso class) and conversion of Hiei from battlecruiser into a battleship. He also worked for the Kaba-class destroyers designed and became commander on 1 December. In 1913 he became Director of Shipyards for the Imperial Japanese Navy, a very coveted title comparable to CNO, and awarded the Order of the Sacred Treasure on 28 November, and a new time by November 1915 as he managed to speed up the efficiency of Japanese shipyards under heavy strain to provide ships to the allies (and another award on 25 February 1926).

In 1916 he was the chief engineering director behind the “Eight-eight fleet program”. He focused on a new breed of high speed battleships and cruisers. On 1st April 1917, now ranked captain and rear admiral from June 1922 he closely followed discussions leading to the Washington treaty with dread. On 7 November 1920 he was awarded the Order of the Rising Sun for his innovative deisgn for the cruiser Yubari, his first really 100% own project.
He was soon appointed a technical advisor to the Japanese delegation sent to the Washington Naval Conference until August 1924. Back home he was promoted to the head of the Imperial Japanese Navy Technical Department and vice admiral in 1926.
He assembled his own design tem around picked-up engineers to create a new fleet within the Washington Naval Treaty boundaries, severely restricting Japanese designs and forcing him to take many innovative design approaches (mostly saving weight) for cruisers and destroyers. His shiped became extraordinarily powerful for their tonnage, using assembly and construction techniques among the most advanced at the time. His famous work was to bring about heavy cruiser better armed than the competition while still well below the 10,000 tons limit (about 8,500 to 9,000 to plan for future additions).

However perhaps enboldened by these enegineeing feats, the Imperial Japanese Navy General Staff often ordered that more weaponry despite Hiraga’s objections over strength and stability. The Mogami-class cruisers were perhaps the most striking exampkle with no less than 15 6.1-inch guns over a 8,500 tons tonnage. In fact these feats only came through “generous” underestimation of their true displacement as well as sacrificed in hull strenght and stability as shown by the Tomozuru incident. By 1929, his last project, the planned Kii-class battleship (never completed) was ended abruplty by the naval staff and retired from active military service in 1930, now just an advisor for Mitsubishi shipyards, in part tired and disgruntled by the attitude of the Navy.

In April 1934 despite all his previous warnings he was part of a board of inquiry after the Tomozuru Incident. His reputation suffered even further in the Fourth Fleet Incident, forcing the Fubuki-class he designed for a rebuilt after a typhoon. Nevertheless he managed to clearly establish his own warnings and was eventually released, and even appointed in the design team in charge of the Yamato.
In December 1938 he became President of the Tokyo Imperial University and conducted a “Purge” of those having liberal political doctrines. On February 17, 1943, Hiraga died at Tokyo University Hospital after a pneumonia, posthumously awarded with the Grand Cordon of the Order of the Rising Sun and kazoku peerage as baron. His grave is now located at the Tama Reien in Fuchū, Tokyo.

The 1934 Tomozuru incident and consequences


As seen above, both this incident, compounded with the 4th fleet typhoon drama, was a incident which implied a torpedo-boat of the Chidori class. Japan like Italy and Germany looked at TBs as a way to create more warship tonnage out of the authorized destroyer tonnage. They could be useful notably in the confines of the China sea, Japan sea, Jorea sea or Pacific islands chains. But industrial limitations only generated two classes, the four Tomozuru (launched 1933) and eight Oroti class (1935). Soon the naval staff priorities changed for escorts, like the Shimushu class (launched 1939) followed by many more.

As for the incident, IJN Tomozuru incident happened soon after the ship entered service, on 24 February 1934. She joined the 21st Torpedo Flotilla at Sasebo and on 12 March 1934, departed for a night torpedo exercise with the IJN Tatsuta and he sister ship Chidori, marred at 03:25 by stormy weather and ordered to return to base. However soon radio contact was lost and her lights disappeared at 04:12, a signal she had probably capsized. A rescue started ten hours later, the capsized hull spotted drifting but there was none to save, 100 of her crew was lost in the rapid capsizing. She was was towed by Tatsuta to Sasebo for an investigation.

After weeks of intensive scrutiny it was established instability was the cause, as they played with the Washington treaty of 600 ton, but were given the armement of a 1,200 tons destroyer essentially. She received under Hiraga direction a lighter construction manking her top heavy. Their unbalance centre of gravity proved even higher than feared and efforts made to remedy it, as shown by her sea trials, by adding hull bulges on Chidori and applied to Tomozuru, and her sisters, with the added benefit of filling these with extra oil (so better range). However the incident happened when she was very low on fuel/water that would have used until then as ballast, hle having full ammunition load. The combination with what was perhaps a near-rogue or very high wave taken from a bad angle was probably the finishing blow. It was estimated that in her condition the situation was worse than on her sea trials.
Do note that the USN Farragut class lost two destroyers in a storm for the same reasons in 1944. They were less top heavy afte their partial reconstruction, but happened to meet the exact same conditions.

Whatever the details, the consequences were dramatic and far reaching. An immense cross-fleet investigation of all ships designed after 1922 was undertook, in search or similar design weaknesses. Recalculations (more detailed and realistic) were made with simulations of similar conditions which led to a rebuilting of the following ships due to their low metacentric height: The Aircraft carrier Ryūjō, the Mogami class cruisers, Fubuki, Akatsuki and Hatsuharu classes destroyers, submarine tender Taigei Minelayer of the Yaeyama, Shirataka, Itsukushima, Natsushima, Tsubame classes, minesweepers of the No.1 and No.13 classes and existing subchasers. The total cost was worth one or two battleships and had grave financial consequences for the IJN budget planification, delaying several program and shutting down projects.
It completely changed the naval staff initial assumptions over stability issues, and led to valuable lessons for future designs across the board. Superstructures were reduced, bulges added, over deck structures lightened, ammunition dug below decks, and armament downgraded in 1934-35. The Mogami-class cruisers were probably the most heavily modified of all these ships, at again, a cost superior to the construction of an extra cruiser.

The Tomozuru affair will bounce back with the loss of several Fubuki class in the 4th fleet incident, in a typhoon, for the same causes.
After 1936 no such incident ever occured again as the metacentic height was now one of the master data to put under scrutiny on all designs. Despite of these stability measures, the cruisers in particular were again compromised by the addition of countless AA guns in WW2, but no such capsizing happened ever again.

The 4th Fleet Incident


Japanese destroyer Hatsuyuki (Fubuki class) heavily damaged after Fourth Fleet Incident – 1935 (reddit)

On September 26, 1935, offshore east of Sanriku in the Pacific Ocean, the Japanese 4th Fleet while in training encountered an abnormal typhoon, 250 miles east of Sanriku coast, which damaged many vessels very seriously and also caused human losses. Bows were cut off from IJN Hatsuyuki, Yugiri, the new Japanese “Special-Class” Destroyers (serie started by IJN Fubuki). Many other ships were damaged or flooded (like Ryujo).
Waves far larger than first expected were the primary cause. But it was serious enough to be investigated, and new facts discovered. The main consequence, was a reinforcement of many ships across the board. The even confirmed tendencies in naval construction were risky at best, after the Tomozuru capsizing (which showed shortcomings in stability), and highlighted this time structural weaknesses across the board.

This day, the Blue Fleet (1st and 2nd fleets) was going agains the Red Fleet (4th Fleet, assembled temporarily). This large scame fleet manoeuver started in July, until late September (as planned). The rebuilt Yamashiro, Haruna, the Mogami Class and the Hatsuharu Class took part for the first time and much was awaited from their performances.
By late September, the Red Fleet crossed the Tsugaru Straits eastwards, and the Red fleet was expected east of Honshu Island to meet the Blue fleet. Weather degraded very fast from 14:00 on September 26, as a typhoon grew out of proportions, catching the fleet completely off-guard. The first largest waves simply knocked off the bridges of Hatsuyuki and Yugiri, the one of Mutsu was smashed, the front side Ryujo’s bridge too, and huge flooding followed, while IJN Hosho plunged so deep had flight deck was completely overwhelmed by huge waves, which crashed her deck and leaked into the hangar; All ships present suffered slight or heavy damage.
The Red fleet abandoned its maneuver and gathered off Shinagawa, Tokyo bay. On October 7 onboard IJN Hiei the staff made a reunion to assess the exercize and overall damage (she was the observing vessel of the maneuver). The incident was judged serious enough that authorities concealed it entirely, put all present sailors to secret, and this happened as Japan withdrew from the London Naval Conference soon after and went even more into secrecy.

Analysts were baffled as it was the first time any ship was so badly damaged by waves since the British destroyer Cobra split in half by 1899. This just confirmed worrying signs after the capsizing of Tomozuru, and put into question the whole Japanese shipbuilding practices. A commission of enquiry was setup in place and led an investigation, (also looking for scapegoats, this was a naval staff one, which deliberately asked engineers for more armament). It was determined first that the Special-Class destroyers. It was decided also to reinforce cruisers, notably those of the Mogami class, and even aircraft carriers. It shows for example that the Ryujo class, built on the below 10,000 tonnes design to go around the Washington treaty limitations (she was not considered as an aircraft carrier) was not a realistic prospect.
Plates that were recuperated and analyzed showed notably for the destroyer, many welding faults (or too weak bonds) and cracks developed after years of vibrations and intensive use. But since thos was merely a political matter, the naval staff looked to blame the shipbuilders and chairman Admiral Kichisaburo, assisted by Vice Admiral Isoroku Yamamoto and Rear Admiral Mineichi Koga. They heared notably Yuzuru Hiraga and his assistants.

On October 21th, 1935, a new special investigative committee for the improvement of the efficiency of naval vessels was established under the lead of Admiral Seizo Kobayashi, which was poised to find the most effective measures to deal with the structural weaknesses observed. These went on for five months and released a very detailed report in April 1936. It was also underlined that vessels appeared heavier than first designed, either when completed and fully loaded, or remarkably heavy after alterations. They established that welded ships proved to have reduced body strength also, and required extra internal bracing, better welding or riveting of some parts. Engineers put to the task found it was not easy to calculate and apply stresses in severe conditions. And the naval staff wanted these reinforcements must affect performance as little as possible. This became rapidly a daunting, hair-splitting and time consuming work and it was felt by some it would endanger National defense at that time. The government wanted to keep costs low, adding more strains in the effort.

Most of the smaller ships went into dock, their plateing and decks stripped and rebuilt, Bridges separated and re-braced. As it appeared welding was overused this immature technology. Also the Design process and construction techniques were reviewed across the board. Critical parts of the hull’s strenght were reevaluated and riveting reappared. They were used for example on Yamato. All these countermeasures efforts of all concerned bore frtui ultimately, with the last ship out of the yards in December 1938 already. They could therefore perform their missions without any further problems afterwards, but this caused immenses delays and extra cost to the fleet as a whole.
Rear Admiral Keiji Fukuda (later promoted to Technical Vice Admiral later) and Prof. Yuzuru Hiraga, assumed most of this daunting work, but this took a strain on the latter’s health, which soon retire from active involvement in naval construction afterwards.

This kind of event was not limited to the IJN however. Famously, the latter “had their revenge” in wartime: The U.S. Navy’s 3rd fleet under the command of Admiral Halsey, was heavily damaged by two typhoons during the Pacific War. Notably many ships were damaged, including some of the Essex-class carriers had their flight decks mushed and collapsed. On December 18th, 1944 in the Philippine sea, 3 destroyers capsized and sank, 18 vessels were badly damaged, 9 were slightly damaged, 183 aircrafts, 700 lives lost. It happened again off Kyushu on June 4th and 5th, 1945. This time, four battleships, two aircraft carriers, two light aircraft carriers, four escort carriers, three heavy cruisers, four light cruisers, and 17 other vessels were seriously damaged, most of the aircraft deck park thrown overboard or destroyed by giant waves. There too, draw consequences for US naval shipbuilding, notably by avoiding stability issues and oil-tanks consumption and supply procedures (this caused the loss of three destroyers in the first case). The Essex-class for example received “typhoon bows” when possible and the Midway class had them installed while in completion. Would this have changed things if the US intel had the knowledge of the 1935 incident ? Debate is launched.

Characteristics of IJN Cruisers


Cutaway of the Nachi class from “Imperial Japanese Navy Heavy Cruisers 1941–45: 176 (New Vanguard, 2011) by Mark Stille (Author), Paul Wright (Illustrator).

As already seen above through Hiraga’s design philosophy and incidents, the designs of early IJN cruisers (Yubari was a pre-Washington design, which stayed experimental, only to test new construction techniques) proceeded with two main concerns in mind: The heaviest armament possible, on the lighter displacement possible, and keeping speed at the top end of their class. Protection was not secondary. These early cruisers were not “paper cruisers” such as those French and Italians of the early 1920s. But there were clearly three eras to separate:
-The WWI program cruisers (Tenryu, the Kuma, Nagara and Sendai classes): These were scout cruisers, armed with single-mount pieces, at best with 2.5 in of armour on a partial belt.
-The post-Washington design cruisers: This included the new generation Furutaka and Aboa (4 ships), brand new designs based on the experience of Yubari but with heavy artillery of 8-in guns as in all navies of the time. And this included the Nachi class (designed in 1923), Takao class (designed in 1926), just much larger and better armed, and the Mogami class (designed in 1930), but revised after the London Treaty with 6-in guns.
-The Post-Tomozuru incident (1934): The Tone class (design revised in 1934 just after they were laid down), Katori class (which were school cruisers) and the WW2 Agano and Oyodo class intended as replacement for the WWI program cruisers.

The appreciation of design specifics for comparisons only concerned largely the Nachi, Takao and Mogami. Indeed the Furutaka and Aoba were merely “light cruiser” by displacement and an arguably lower armament than contemporary heavy cruisers and can be seen as steps towards the definitive IJN cruiser designs of the interwar, still testing many solutions. They are not representative of the whole picture.

Yubari was a prototype, and the design solutions were mixed with the need of a heavier armament proceeding by steps, single turrets on the Fututaka before rebuilding, and twin turrets with superfiring turrets with the Aoba. It was all-Japanese, since Britain ended its alliance with Japan in 1923. These “test cruisers” paved the way for a much more ambitious design, which was to this time answer to any regular British or US cruiser design of the time. The goal was simple: More guns and more, better torpedoes first and foremost. AA artillery was secondary.

Speed was paramount, and all this was to be done under the 10,000 tonnes limit officially as long as Japanese offices remained open to the west (which was no longer the case when the Yamato class was started). The fact Japan retired from the second London conference made it free to launch several reconstructions (like the Mogami class being the most spectacular) which implied also the Nachi and Takao, and naturally pushed their tonnage well beyond the 10,000 tonnes limit. In WW2 for example, they looked towards 14,600 tonnes or above. The Tone class (launched 1937) was even above treaties from the start, with 11,215 tonnes standard already and up to 15,600 tonnes later in WW2. They all gained bulges and were considerably reinforced structurally.

Armament


IJN Atago’s main turrets

Armament-wise, the cruisers went from six 8-in guns (203 mm) on the Furutaka-Aoba, to a staggering ten on the Nachi-Takao-Mogami (the latter before swap to 6-in guns); This made them the most gun-heavy cruisers of the interwar. The closest were the US cruisers adopting triple turrets (for nine guns) on the Northampton, New Orleans, and even the wartime Baltimore class. The European standard was eight guns in two twin turrets. The way to shoehorn a fifth turret however ment some sacrifices.

The hull was lenghtened, and the turret N°3 was placed between behind the superfiring N°2, meaning it was facing the bridge and had a more limited arc of fire, only potent in broadsides, but neither in chase or retreat. The mogami improved this as having the N°1 and 2 on the same deck level and N°3 raised on the superstructure, enabling more leeway and a six guns chase fire. The Tone were even more radical with a return to four turrets but all forward, a superfiring pair followed by two deck-level turrets facing the bridge. A unique approach enabling space aft for an air group. Something never seen in any other design worldwide.

The other shining point of the designs, purely out of Japanese newly developed night combat tactics with only cruisers and destroyers, favored an aggressive use of the torpedo. Indeed, from the Furutaka’s originl fixed tubes in pairs were substituted two quadruple banks at deck level after reconstruction, abd same for Aoba. But originally they could fire six torpedoes on either side.
The Nachi adopted these traversing banks early on, in four triple banks inside niches in the superstructure aft.

They thus passed from eight to twelve, six either broadside and reloads. This scheme was repeated on the Takao class (relocated amidships) and Mogami, Tone class as well. Many were later removed to spare weight and add extra AA. As for the light cruisers of the Agano-Oyodo they are to be compared rather to what they replaced. The Kuma-Nagara-Sendai had four twin tubes, four torpedoes on either broadside. The Agano planned as destroyer leaders had two axial quaduple banks (so also eight tubes) like on a destroyer, and this placement enabled more stability and a full broadside, twice the cruisers they replaced. The larger Oyodo due to her role had no TTs at all.

50 caliber 3rd Year Type 20 cm Gun 1 GÔ (No. 1)

This was the official designation for the main guns of the Akagi and Kaga initially, and the cruisers of the Aoba/Furutaka classes, as well as the Myôkô class.
These 17.6 tons (17.9 mt) had a rate of fire of 2 initially (Kaga) and up to 3-5 in the later version. Approximate Barrel Life was 300 rounds and the ships had about 120 rounds in store for each. Range at 45° was 30,620 yards (28,000 m). More

50 caliber 3rd Year Type 20 cm Gun 2 GÔ (No. 2)

The “modern” 203 mm (8 inches) caliber, found on the Takao class. They tried to correct large dispersion patterns, and were fitted on the Takao and Tone classes as well as the rearmed Furutaka, Aoba, Myôkô and Mogami classes as well as the unbuilt Ibuki class. Performances: 3-4 rounds per minute, range 27,340 yards (25,000 m)/30°, 1,247 fps (380 mps) terminal velocity, able to defeat 2.9″ (74 mm) armor at 30,000 yards. More

60 Caliber 3rd Year Type 15.5 cm Gun

When the Mogami class were rearmed with lighter guns following the Londong treaty signature in 1930, these were the new guns adopted. They swap back onto the 20 cm guns again after reconstruction 1939-41. Their former mounts were reused on the Yamato class battleships and light cruiser IJN Ôyodo (which had two such turrets). They had a slow rate of fire and limited elevation and were useless as dual-purpose but stayed accurate in their anti-ship role. Their theoritical rpm was 7, but in reality only 5-6 rounds per minute was achieved. Range 27,340 yards (25,000 m)/55°. They could defeat 4.2″ (108 mm) of armour at 16,400 yards (15,000 m). For the Kuma/Nagara/Sendai classes, see the WWI section.

DP/AA Guns


127 mm (5 in) dual purposes on IJN Chitose before conversion

As standard, these ships were equipped with the following:
45 caliber 10th Year Type 12 cm: cruisers built in the 1920s and early 1930s.
40 caliber Type 89 12.7 cm Gun: Standard DP gun on cruisers in the 1930s. The great standard, 14 rpm/30,840 feet (9,400 m) ceiling. More
3″/40 (7.62 cm) 3rd Year Type: Furutaka/Aoba
25 mm Type 96: The ubiquitous main AA gun of the IJN, present virtually on all ships in single or triple mounts , replacing often the 13.2 mm Type 93 heavy machine gun .

Of course this point would be gravely incomplete without mentioning their fabled Type 93 Torpedo, the famous “long lance”. Although not as famous as the German 88mm, British 17-pdr or the Bofors 40mm, this “secret weapon” was certainly the best asset of the IJN and best torpedo of WW2. Given its results in several “close-quarter” battles notably in the Solomons, and the poor performances of the US Mark 14 conversely, explains partly the crippling losses of the USN until late 1942.
The Type 93 was designed from 1928 by Rear Admiral Kaneji Kishimoto, and Captain Toshihide Asakuma and was accepted for production in 1932.
No nation at the time indeed had a torpedo that carried a larger payload (1018 kgs) to 43,700 yards (40,000 m) at 36-38 knots or going to 21,900 yards (20,000 m) at 50 knots.

Other Torpedoes

61 cm (24″) Type 8 No. 2 (1920): On the Kuma/Nagara/Sendai classes
61 cm (24″) Type 90 (1930): Interwar heavy cruisers, Aoba, Furutaka, Nachi/Takao before replacement by the Type 93.
61 cm (24″) Type 93 (1933): Model 1, Mod 1, Mod 2 and Mod 3, all cruisers in 1941, including the unbuilt Ibuki class.
61 cm (24″) F3: First Experimental Turbine powered torpedo, 17,500 rpm geared down to 1,650 rpm at the propellers but capricious and not adopted.

Powerplants and performances


Differences between a Yarrow and Kampon boilers drum arrangement

The oldest cruisers in service in 1941, mainly converted as minelayer/training vessels from the late 1890s or 1900s still around indeed had quite antiquate machinery limiting their top speed to 18-20 knots making them unable to take part in any fleet exercize. The Asama-Idzumo (Armstrong), Yakumo (Vulcan), Adzumo (Loire Yards) had different powerplants but all were VTE, coal-burning. It seems none received any engine upgrades. The scouts of the Chikuma class (1911), still around in 1940-41, had Parsons/Curtis steam turbines and Kampon boilers and mixed coal/oil burning.

Next, were the active ships of the Tenryu class (1918): First with Brown-Curtiss turbines to achieve 33 knots. This became the new IJN speed standard for the fleet. After all they were destroyer leaders. The first cruisers with national turbines were the Kuma class (1919) which had Gihon steam turbines for 36 knots, and moslty oil-burning. This was repeated on the Nagara class (1921) and even on the Sendai class (1925), which all shared the same 90,000 bhp powerplant. They typically carried 2/3 oil and 1/3 Coal.
The transition to oil-only was not yet achieved on IJN Yubari, which was revolutionary at other titles. She had three shafts, not four as usual, same generation, but more compact geared turbines to reach 35.5 kts. The Furutaka and Aoba as built also carried a mix of Oil/coal and were capable of 34.5 kts (less after modernization).


Kampon Ro-Go and Type B boilers

However innovation came from the next heavy cruiser generation of the Nachi and Takao class: They had still four Gihon geared turbines, but coupled with 12 Kampon new generation boilers, burning only oil. With 130,000 shp they reclaimed the speed lost at 35.5 kts, while the Mogami class had a new generation of superheated boilers, and with just ten, achieved 152,000 shp for a record 37 kts. They were the fastest cruisers in Asia. That is, before their reconstruction. The added tonnage made them closer to 35 kts at best in early 1942.
The Tone class (1937) still managed the same output with eight boilers, but kept at 35 kts as the fleet standard.

Exhaust and boilers arrangement on a Takao class cruiser
Exhaust and boilers arrangement on a Takao class cruiser

The small Ibuki class were an exception, designed as training/HQ ships. They mixed diesels and turbines for extra range (which was exceptional) and with just three boilers, only achieved 8000 hp, for 18 kts, escort speed. The light cruisers of the Agano class counted on the same powerplant as the larger cruisers, but with just six boilers in a compact arrangement. These slender vessels achieved 35 kts, sufficient for their task. The Oyodo, single in her class, had about the same arrangement but were a bit more powerful at 110 instead of 100,000 shp. They all had four drive shafts and three-bladed bronze screw propellers. It must be said that interwar aicraft carriers copied cruisers powerplants to achieve speed in excess of 36 kts (Notably Soryu/Hiryu), making them the world’s fastest aircraft carriers (The lexington class came close at 33 kts).


The gargantuan Kampon Mk.25 mod 2 diesels in 1944

As for the Ibuki class, she was not innovative in particular: She started as a repeat of the Mogami class, but when decision was made for a conversion, the first and single ship of the class modified had her powerplant halved to make room for extra aircraft, ammunition or avgas tanks: She ended with two shafts and geared turbines fed by just four Kampon boilers for 72,000 shp and 29 kts (as planned).
The heavyweights in this serie were also also unbuilt “B64” type cruisers: These were more capital ships than “cruisers” and were capable of 160,000 shp for 33 kts.

Protection


Takao class midship armour scheme. It shows a relatively common trend at the time, with an inverted external sloped belt, central turtleback type section, well compartimented ASW compartimentation with bulges also used for extra stability, divided into crush half-tubes. They had no conning tower, and only the ammunition magazines were the best protected parts of the ships, with 100 mm thick boxes, deep inside the ship, counting on the energy dispersion effect of the decks above. Indeed, cruiser’s ammunition explosions has been exceedingly rare, but cases of spare torpedoes detonating was not unusual.

It varied from ship to ship, and types. We are going to start with active cruisers in WW2, the Tenryu class and 1919 programme. As scouts, these were lightly protected, intended to only fight other destroyers. It was limited to a 2-in belt (51 mm) and 1-in deck (25 mm), creating a small “immune zone” on a very limited distance, representing 1/3 of the ship and centered around the machinery spaces. In comparison even the previous Chikuma class were better protected. However these new cruisers were capable of 33 knots, same as destroyers, making them more difficult to hit anyway.
The trend was continued on with the next Kuma, Nagara and Sendai which had about the same scheme. “Immune” area around the machinery space, but thicker at 2-1/2 inches (63 mm) and 1-1/2 inches (32 mm) respectively for the horizontal and vertical protections. The Sendai class (1925) were about the same, 2.5 and 1.1 inches respectively.

The experimental Yubari (1923) designed by Hiraga, experimented a new kind of structural protection, and it was installed internally and sloped unlike previous cruisers. And it contributed at the same time to the longitudinal strenght of the hull, a way to used all available steel plating count in a dual role. This way, this made the structure lighter overall. But fugures were still limited: 2.3 in for the internal belt, shorter than the outermost barbettes, 1-in (25 mm) both for the armored deck and gunhouses.
For the early heavy cruisers of the Furutuaka-Aoba class, the same recipe was applied, but the belt reached 3.4 in (86mm) -even 3 inches on Aoba- and the deck 1.4 in (35mm), the gunhouses (turrets) stayed at 1-in. If they were intended to combat other 8-in armed cruisers, this was ludicrously light.

For the Nachi class, at least the belt was augmented to 3.9-in (100 mm) but the deck armor remained the same, as the turrets, but at least the main barbettes were augmented to 3-in (76 mm). The next Takao class had the same scheme, but this time localized areas were better protected, as the ammunition magazines, boxed into 4.9 in (120 mm) compounds. The bridge was absolutely massive and abl to “absorb” extra punishment. As for the Mogami class, they followed the general trend of all Washington cruisers, and improved their protection a bit. The belt remained the same, they had the same boxes magazines, but a better, layered deck protection ranging from 1.4 to 2.4 in (35-60 mm).
The Tone class had the same scheme, but with 1.2 to 2.5 in for the deck protection. Protection of the turrets was still paper thin (1-in/25 mm). The next Ibuki class was a repeat of the Tone class scheme.
It must be said a few authors pretended that Japanese steel was naturally of general better quality, given perhaps the local ore, adding to the protection, in addition to Hiraga’s construction “wizardry”. It’s not the case. All sorts of stell qualities were recycled if possible, and the reputation of Japanese swords was not due to the material use, but the skills of the master smiths. The fundry tech in Japanese was borrowed from western techniques, mainly those of Britain originally, and through their purchases, Japan tested Krupp and Harvey armor as well. They did not came with a revolutionary “special process” for hardened steel of their own, at least one that is know of.

Radars

22-GO_and_13-GO_radar_on_forward_mast_of_japanese_destroyer_Harutsuki Japan came to radars a bit later than the allies. It is also often said that their optics were of superior quality and by clar weather, or even by night the “eyeball Mark I” was still the best long range detection asset of the IJN, this was especially true in the Solomons. Optical detection used to out-range US radar detection, especially because of the surrounding relief. The main types were the Ta-Se 1 Anti-Surface Radar and Ta-Se 2 Anti-Surface Radar. Hiwever the Japanese developed 30 different types of sets and had 7256+ sets of all types built. Late and far less effective than that of the Allies, they still were fitted on all surviving cruisers from 1943 onwards. Some cruisers had their mainmast rebuilt as derricks to support large aerial warning sets.
More on the topic.

IJN Cruisers in action in WW2


IJN Nachi in sea trials
Cruisers were classed in three categories, which defined their roles, depending on their capabilities:
-The pre-WWI cruisers still active (mostly armoured cruisers) were reclassed as training ships or minelayers and used as such.
-The 1919 program cruisers (Tenryu, Kuma, Nagara, Sendai) were considered obsolescent in 1941 and used generally (there were exceptions) as assault forces escorts, also providing fire support. In some rare cases they were used as destroyer leaders, but not ion the fleet screening role. Their role was retaken by the post-1942 Agano class, but by 1944 they were used to replace loss in standard fleet operations. IJN Oyodo was never used as intended (leading submarine attacks), and ended as fleet HQ ship. The Katori class were used as escorts for convoys and assault forces, and floating HQs, so about the same as above.
-The “fleet cruisers” (Furutaka, Aoba, Nachi, Takao, Mogami and Tone classes) were the real deal, used as part of combined fleets with battleships and carriers, or independently with destroyers, notably for cruiser forces interception (like ABDA in the west indies, or Solomons fleet moves). By default of battleships, the US used their cruisers, and the IJN answered the same, keeping their capital ship for more important operations. As befitting of cruisers, they could act independently with the escort of a few destroyers.

As said above about radars, the IJN developed the reputation of markmanship’s gunners. They also had generally good gunnery direction. There were excellent optics in general and they tended to detect their foes earlier. Not only they were able to place salvoes on target consistently but also at longer ranges.

Onboard air groups and hybrid cruisers


IJN Oyodo, a standard hybrid cruiser intended to lead submersible attack groups on long range missions, equipped with the mediocre Aichi E 16 A Zuiun “Paul”.

The other factor was long range reconnaissance, well above the range of any radar. These cruisers had generous seaplane provisions, and in fact tactically were often used as “eyes” of the fleet. When integrated into combined battle formations, they screened the capital ships and sent their seaplanes before any engagement to sport and report the enemy formations. This was crucial for the “first air strike”. Let’s take two models to have a clearer view of this:


Kawanishi E7K2 “Alf”. This long range reconnaissance model was standard on all cruisers in 1941 (here IJN Abukuma).

Nakajima E8N2, IJN Nagato, 1941.

Note the different in size. This was also traduced in range, which nearly was double on the Cruiser’s models. The contemporary E8N was more an artillery spotting model.
They were replaced by the Aichi E13A and Mitsubishi F1M respectively. 1919 program cruisers only had an axial catapult and single model, but later fleet cruisers had two or even three of these, a small hangar, two catapults and a deck trackway to store and dispatch non-mounted models. Usually there were two mounted on their catapults and a third, wings folded, kept in reserve. Even the small Agano had two. Some cruisers were even transformer to carry more: The Tone carried six as the Oyodo, and the Mogami was completely rebuilt also as an hybrid cruiser. This also concerned battleships, with the Ise class also rebuilt that way in WW2.
They played an important role in several engagements, reporting enemy fleets, but never really filled all the hopes placed in them. The case of oyodo is interesting by the way and Mogami also carried models intended to carry torpedoes and bombs.


Probably the best “observation/fighter” aboard IJN cruisers was the F1M “Pete”.
It was also not unusual for cruiser’s floatplanes to fill the role of carrier aviation, downing enemy aircraft (it was often the case over China) or supporting troops during assaults. Probably the best floatpolane “fighter” actually carried by cruisers was the Mitsubishi F1M “Pete”, which was high performances despite it’s biplane configuration. In fact the theoretically better A6M2-N “Rufe” was never adopted for cruiser service, kept for the defence of isolated island garrisons.

Cruiser Doctrine since 1894

One Famous cruiser tactic was the night combat:
A whole doctrine was developed around it, maximizing the cruiser’s heavy torpedo armament. Some early principles were also laid down by Baron Vice Admiral Tsuboi Kozo. A Rear Admiral in 1894, he led a special force of four extremely modern cruisers, called the “Flying Squadron” of the Imperial Japanese Navy during the 1st Sino-Japanese war and at the Battle of Yalu. He was not content to just act as a scouting force for the main fleet but took his squadron on long distance “reconnaissance-in-force” missions. Instead of dispatching his four cruisers separately for commerce warfare, he kept them together to put under heavy fire any encountered hostile unit with Guns and torpedoes. He wanted this unit to move quickly and striking key locations in rapid succession with surprise and strength. This unit became famous and had a legacy teached in the Etajima naval academy all the way to WW2. In between onboard aviation appeared, and later torpedoes were developed to a further level, enabling new capabilities.
The question of artillery was also an issue: Kubo’s squadron only had slow-firing 8-inch guns, fine against armoured cruiser but usuless against destroyers at short range. The concept of fleet light cruiser was developed in the IJN after the Second London Naval Treaty.

These tactics centered around a powerful cruiser force was put to good use at the Battle of Sunda Strait, Java Sea and Savo Island.
Nevertheless, the Japanese fleet devised two general types of surface warships (neither capital nor carriers), mainly torpedo carriers with secondary gun batteries, and mainly gun carriers with secondary torpedo batteries. Destroyers represented the first category, and heavy cruisers the second.
There was still the need of a combo between heavy cruisers and large light cruisers, as the Mogamis and Tones were originally meant to be, before reconversion. Combining long range gunnery with rapid fire against enemy destroyers would indeed have made these combinations more effective.

Organization and Use

From December 1941, the IJN mustered its eighteen heavy cruisers and four supporting fast battleships (Kongo class) actively used for the conquest, with destroyers supporting screens. They were dispatched to operate over half the Pacific, organized into five cruiser divisions (which were classes) and five supporting forces. Two of these five supporting forces had a pair of fast battleships each. These forces could have both land-based or carrier air based support (such as the forces which claimed Force Z), sparing the IJN a potentially challenging surface combat.

1942 divisions (“squadrons”):

ATAGO class (CruDiv 4): Atago (F), Takao, Maya, Chokai
NACHI class (CruDiv 5): Nachi (F), Haguro, Myoko (F), Ashigara
AOBA class (CruDiv 6): Aoba (F), Kinugasa, Furataka, Kako
MOGAMI class (CruDiv 7): Mogami, Mikuma, Kuman (F), Suzuya
TONE class (CruDiv 8): Tone (F), Chikuma
CruDiv 16 (formed 1943): Aoba (F), Ashigara, and two light carriers
CruDiv 21 (former 1942): Nachi (F), Maya/Ashigara, two light carriers
(*F: Flagship)
They were assisted by destroyer squadons with various strenghts, sometimes as low as two ships.

The Indirect Escort of Convoys from March 1942 on counted on three heavy cruiser divisions (12 ships in all) screening landings over the Pacificn with CruDiv 7 taking on Malaya, Sumatra, and western Java, CruDiv 5 the Philippines, Celebes, and eastern Java, CruDiv 6 Guam, Wake, and Rabaul. The distant cover meant the transports did not even saw them, but closer, older 1919 program cruisers as direct protectors. This never led to troubles as the allied response was so weak at first. In addition this organization meant the heavy cruisers were not stuck to close protection and could be detached of need be:
This was case at the Battle of the Java Sea (February 27, 1942) when Nachi and Haguro until then attached to the support of 41 transports, went sent to fend off the ABDA Allied cruiser force. They were repulse three times over seven hours. Long-range daylight battle was not in their favour however with only six hits scored after an hour, but victory was secured in a night action at 8000 yards with torpedoes (also fired from destroyers) working their magic. The Dutch navy was equally unaware of their range, as their allied counterparts.
However this indirect support was not always successful: It failed in Makassar Straits as the supporting Japanese cruisers were too far north to inetrvene, and when USS Houston and HMAS Perth ran into a fleet of transports while under hot pursuit (by the cover cruisers) off Java, they sank four of them. Mogami and Mikuma were again not present.

In the attempted capture of Port Moresby in May 1942 the four Aobas (CruDiv 6) were reployed in screening the support carrier force, while CruDivs 5, 6, and 7 were screening the invasion force proper, and CruDivs 4 and 8 were in close protection of the Kido Butai. The 8th screened with the fast battleships Hiei and Kirishima. They were a kind of “supporting force of the supporting force”. The Kido Butai had de facto the most powerful screen force at the time, four fast battleships and six heavy cruisers. These cruisers provided intel, via their seaplanes, notably Tone and Chikuma. This early phase saw only IJN Myoko damaged, at Davao by a B17 bomb on January 4.


Haguro in the raid of Rabaul, November 1942

A fast bombardment force was later built around Cruiser Division 7. CruDiv 8 at Midway failed to prevent the destruction of the four carriers. Tone’s floatplane sighted USS Yorktown, allowing the IJN some retribution at last. CruDiv 7 failed as the mission was aborted following the disater, Mogami rammed Mikuma after a sub sighting and later Mikuma was sunk and Mogarni severely damaged by US Carrier planes.

During the Solomons campaign these heavy cruisers were used for antishipping raids, and shore bombardments, notably at Guadalcanal, their use evolving along the situation on the ground. The night raid on 8-9 August which fed the future “ironbottom sound” was by far the mpst successful. They approached undetected due to the surrounding volcanic peaks and hills, defeating the US primitive radars, fired torpedoes and finished the job with heavy guns at close range, acheving complete surprise. The US lost four cruisers that night, including three New Oerlans class in one go. The remainder of this one-year gruelling campaign the Japanese would try to replicate that success.

In the next daylight two carrier battles of Eastern Solomons and Santa Cruz, cruisers fare with little success, due mostly to their inadequate AA. But again, reconnaissance planes of those were decisive: On August 25, one of Chikuma’s seaplanes sighted the USS task force (USS Saratoga and Enterprise). They also fought not decisively in subsequent actions and were limited afterwards to bombardment runs of the “Tokyo Express”, not carrying supplies or troops themselves, as too precious.
After the Battle for Guadalcanal these cruisers were pulled back and retired in the central Pacific, notably to operate from Truk.

Nachi, Maya, Aoba, and Ashigara were more active, with the first two part of the 21st Cruiser Squadron with Tama and Kiso, seeing action in the Aleutians (5th fleet).
The last two were sent to the 16th Squadron with the light cruisers Oi and Kinu in the South Pacific. In both cases they acted as distant support, the two older cruisers being in close protection of the troopships.


Nachi at the Battle of Manila Bay, 5 November 1944

At the Komandorski Islands Nachi and Maya perfrormed poorly against an inferior force. They landed only 0.33% hits out of 1,800 main rounds fired on Salt Lake City and all their torpedoes missed. Myoko and Haguro fared little better at the Empress Augusta Bay on November 1, 1943: Without effective radar they lost 30 min. firing poorly, and were damaged in between. Despite the oppostion only had 6-in guns, they did not excelled in markmanship to say the least, and retiring with damage after achieving little.

As for the central pacific, a major raid at Truk damaged Atago, Takao, Kutnano, Tone, Mogami, and Maya, while Suzuya and Chikuma escaped unharmed. At Saipan they were mostly absent, and in the Philippines this was mostly an air war, and again, they could do little with their inadequate AA to protect the fleet.


IJN Takao “rotting”, camouflaged in Singapore, as captured by British forces

The last occasion of a naval action was at the battle of Leyte in October 1944: But eight Japanese heavy cruisers were lost in the battle, the bulk of the fleet. After that Tone and Aoba were sent in Kure for repairs and never left home waters before their execution in the summer of 1945, whereas Myoko, Takao, and Haguro were sent permanently to Singapore, Ashigara in Indochina. This was pretty much game over for the IJN Cruisers at this juncture.

Night Combat

< Raizo Tanaka, a master cruiser tactician. There is a long legacy to the concept.
The Japanese navy specialized in the early interwar in a new kind of “night torpedo action” bringing their new heavy cruisers into very close range, putting to good use the range of their torpedoes, something completely overlooked by the USN. The Battle of Savo island was a textbook example of this, but it was not the only one.
However a usual, fate has these plans not working on the long run. The US had better radars ultimately and used their submarines in very efficient ways to detect enemy forces. The Japanese staff had to decide ultimately to use their “tokyo Express”, based around a core of cruisers, to resupply by night their beleaguered troops on Guadalcanal. This led to several night actions with various fortunes.

Too many limitations

The IJN, even after eliminating the bulk of the USN capital fleet at Pearl Harbor, continued to consider heavy cruisers as the backbone of their operations, with fast battleships ready to support them a la Hipper (usually the Kongo class specifically), but they were still too few and precious to be committed each time. To put it mildly heavy cruiser squadrons put most of the fighting, while the Japanese battleline accumulated barnacles in the Inland Sea, notably “Hotel Yamato”, despite being the most formidable asset until the USN reclaimed total air dominance over the Pacific. This was compounded with the failure of the IJN to recoignise the danger of US Submersibles tactics early enough. They too, preyed on these hard-pressed cruisers.

However in the end, the failure to consider cruisers with rapid-firing medium guns rather than sticking on armour-piercing heavier guns -the after effect of a long obsession with circumventing treaty limits- eventually produced a fatal gap in tactical firepower capabilities. With their generally good heavy cruisers but mediocre light cruisers, the fleet lacked intermediate, modern large or medium light cruisers that can fill gaps, comparable to the USN Brooklyns/Atlanta in 1942.

The IJN industry was nowhere near the capability of the US industry to provide these, as shown by the small number of Agano built (4 of 24 planned initially), Oyodo (One on 12 planned) or Ibuki (none, converted to CVL). Changing priorities converged after the disater of Pearl Harbor to aircraft carriers and smaller escorts. Or even “super destroyers” to fill that gap. IJN’s Agano class were still a prewar project completed in wartime, IJN Oyodo being the real only Japanese wartime cruiser (launched 1943) taking some lessons of these deficiencies, but making the choice of an hybrid configuration. It was large enough to have been given three or even four tripl turrets with 6-in guns.

To compare at the same time, the USN laid down more than 65 keels for light cruisers (Cleveland and Atlanta class) and 30 keels for heavy cruisers, completing most of them, the Royal Navy itself commissioning also many new cruisers during that time.
This lack of resources meant efforts were concentrated on aircraft carriers, escorts, “secrets weapons” such as the Kaiten submarines, or Shinyo Motor Boats, the Yamato and Mushashi absorbing most of available the resources in 1941-42. Would more cruisers had changed the nature of the fight in 1942-43 ? Not really, as air power was the dominant factor, but until the Japanese retired from Guadalcanal, operations were mostly led by Cruisers, especially by night, and they proved very efficient.

USNI Japan’s Heavy Cruisers in the War (1950)
US Postwar assessement of IJA night combat
See also the tabular record of movements of the cruisers

Vintage IJN Cruisers in WW2

IJN ww2 Tsushima (1902)

Japanese_cruiser_Tsushima_in_1905
Hulked 1930. Sunk 1944. Also hulked, IJN Adzuma, but in 1941. Survived the war into 1946 and BU. On 1st September 1921, IJN Tsushima was re-designated a “2nd class coastal defense vessel”. In 1922 seh received six modern 15.2 cm and eight 12-pdr (3 in) guns. Later in the 1920s she was given a single 12-pdr AA gun. She became the main patrol vessel on the Yangtze River and Kichisaburō Nomura’s flagship, at the head of a gunboat fleet.
IJN sushima was partially disarmed in 1930 and became back home a training ship, struck in 1936. She became “training hulk Hai Kan No. 10”, annchored at Yokosuka Naval District, until 1 April 1939. She ended her life as a target ship off Miura (Kanagawa) by torpedoes in 1944.
As for Niitaka, from September to July 1920, she covered landings of the IJA in Petropavlovsk as part of the anti-Bosheviks Siberian Intervention and as fishery protection vessels for Japanese trawlers along the Kamchatka Peninsula. By May 1921 she was patrolling southern China and down to the Netherlands East Indies, and South China Sea. From September 1921, she became a “2nd class coastal defense vessel”. On 26 August 1922, she was based on the southern coast of the Kamchatka Peninsula, sending a landing party of 15 led by Lieutenant Shigetada Gunji ashore, looking for presence of Belsheviks there. Ironicall they became survivors as the while crew disappeared when the ship was caught by a sudden typhoon, with gale winds drossing her onto rocks. She was overturned. A salvage team went there in 1923 to examine the wreck and see if it was recoverable. But it was not to be and the wreck was finished off with explosives, and the metal taken away. She was stricken on 1 April 1924.

IJN ww2 Training Cruiser IJN Asama (1898)


IJN Asama towed in Sydney, 1930s
After the war Asama was used as navigation training ship, performinge long range cruisers for cadet officers. On 21 August 1920, she visited South America and Polynesia but by late 1921 she was re-designated a 1st class coast defense ship. In 1922, her main deck guns were removed as six 6-in, four 12-pdr guns, QF 2.5-pdr guns and casemates plated over. A single 8 cm/40 3rd Year Type AA gun was added however.
From 26 June 1922, her training cruises brought her to Australia, Southeast Asia, and Mediterranean; but she ran aground on the night of 13 October 1935 NNW of Kurushima Strait, Inland Sea. Rngineers estimated that she was difficult to repair. Towed to Kure she was provisionally repaired, and assigned the Kure naval Corps as a stationary training ship from 5 July 1938.


Asama as a barrack ships in 1946. She was BU the next year.
She was reclassified as a training ship in July 1942 and was later converted as a gunnery TS at Shimonoseki, keeping a few 80 mm/40 (78 in) 3rd Year Type AA guns in 1944. But she was eventually stricken on 30 November 1945, scrapped at the Innoshima shipyard (Hitachi Zosen) after the war, from 15 August 1946.

IJN ww2 Minelaying Cruiser IJN Tokiwa (converted 1928)


IJN Tokiwa in 1945
Tokiwa, a former Asama class armoured cruiser built in Britain (launched 1898), was reassigned to the Training Squadron on 10 August 1918 and prepared a training cruise with Azuma from 1 March 1919 for South Asia-Australia. From 24 November she stopped at Singapore, visited Southeast Asia, crossed the Indian Ocean, Suez Canal and entered the Mediterranean Sea, back home by 20 May 1920 and left the Training Squadron in June, reclassed as 1st class coast-defense ship and taking in hands at Sasebo on 30 September 1922, for conversion into a minelayer:
She was modified to carry To accommodate 200–300 mines depending of the type:
-Rear 8-inch gun turret, six 6-inch guns (main deck) removed.
-Rear guns were removed and two 12-pdr retained
-Two 8 cm/40 3rd Year Type anti-aircraft guns added.
The process ended by March 1924 but she suffered whilke in service an accidental explosion in Saiki Bay (1 August 1927) when mines were disarmed. One detonated, fllowed by others and 35 were killed, 65 wounded. Tokiwa was repaired and went to the reserve fleet. From January 1932 she joined the 1st Fleet, until May 1933. She served in China. From November 1937 she was druyocked and gutted, with eight new Kampon boilers, with a speed down to 16 knots (30 km/h; 18 mph), torpedo tubes removed. The freed space enabled to carry 500 extra mines. She was reassigned to the 4th Fleet on 15 November 1939, then 18th Division, 19th Division in 1943 (Rear Admiral Kiyohide Shima) with the other minelayer IJN Okinoshima. In 1940, she received two single 40-mm (1.6 in) guns, 20 Hotchkiss 25-mm Type 96 light AA guns (twin-guns).
On 9-10 December 1941, IJN Tokiwa and other minelayers from the 19th Division escorted two troop transports for Makin and Tarawa. By January 1942, Tokiwa took part in Operation R to Rabaul and Kavieng andlater Kwajalein. February 1942 saw her attacked by planes from USS Enterprise, she was later repaired in Sasebo and was back to Truk on 14 July 1942. On the 19th she joined the assault Makin squadron tasked to reoccupy the Atoll after the USS Raid.

On 1 May 1943, she was part of the Ōminato Guard District. She left Truk on 26 May to escort a convoy to Yokosuka ambushed but missed by USS Salmon (SS-182) in June. She was reassigned to the 18th Escort Squadron, 7th Fleet, on 20 January 1944. She was reamed with ten single 25 mm Type 96 AA guns and 80 depth charges as well as a Type 3-1, Mod 3 and Type 2-2, Mod 1 radars. She layed a large minefield off Okinawa the same month, and off Yakushima in February 1945.

However on 14 April 1945 (78 miles off Hesaki- Kyūshū) she hit a mine, but damage was moderate. USAAF B-29 Superfortress bombers laid mines and she hit another one on 3 June 1945. Caught by TF 38 US aviation while off Ōminato, Mutsu Bay (northern Japan) on 9 August 1945 she took several near-misses and at least a direct hit. Her captain decided to have her beached to avoid sinking. On 30 November 1945 she was stricken and her wreck, partially underwater, was relfoated and towed for demolition in Hakodate, BU in August–October 1947.

IJN ww2 Coast Defence ship IJN Yakumo (1899)

Yakumo_1946
The single German (Vulcan-built) armoured cruiser (launched 1899) was still active in 1918. On 1 September 1921, she became a “1st class coast-defense ship” used for training, as her sisters making long oceanic navigation trips with academy cadets, making 13 of these cruises in the interwar, visiting all continents over time. She even made a circumnavigation of the globe (August 1921-April 1922) with IJN Izumo, with distinguished hosts such as Princes Kuni Asaakira and Kachō Hirotada.
In 1924, her armament was modified: She her most her 12-pdr guns and all QF 2.5-pdr, three TTs removed, but eight single 8 cm/40 3rd Year Type AA guns added. In 1927, she was drydocked for her boilers to be replaced by six modern coal/oil-burning Yarrow boilers from the rebuilt IJN Haruna. He new output was 7,000 ihp (5,200 kW) for 16 knots. She carried 1,210 metric tons of coal and 306 metric tons of oil.

Yakumo off Vancouver, 1933
Yakumo off Vancouver, 1933

With Izumo she landed IJN Marines in Tsingtao by 1932 to quell a riot of Japanese residents and in 1933 she became a training ship. From 6 November 1936 she suffered an accidental explosion while underway between Saipan and Truk. This was in the front ammunition magazine. 4 were killed, but it was quickly flooded. Two weeks later she was repaired. By December 1936 she had a new captain, Matome Ugaki, departing in 1937 for IJN Hyūga. She made new cruises in 1937 and 1939, the last ending on 20 November 1939.

From early 1942, IJN Yakumo was fully reactivated as “1st class cruiser”, on 1 July 1942. Her main guns were by four 12.7 cm (5.0 in) standard Type 89 DP guns in two twin mounts in place of her former 8-in turrets. She also receibed extra 25 mm in triple and single mounts. She was based in the Seto Inland Sea for training until stricken on 1st October 1945. She started repatriation trips in December, notably from Taiwan and mainland China. Her last ended by June 1946, with 9,010 onboard. She was sold and BU at Maizuru (Hitachi Shipbuilding) by July 1946.

IJN ww2 Izumo class Coast Defence ships (1899)


Izumo 1932
The lead ship of the Izumo class, veteran of the Russo-Japanese war participated in the 1919 Naval Review in honor of Emperor Taishō. “1st class coast-defense ship” from September 1921 she also was a oceanic navigation training ship for the Academy, making six voyages in the 1920s-1930s and a circumnavigation from August 1921 to April 1922 with Yakumo. On 7 February 1925 she collided with a tugboat at night.
In 1924 she had a first refit: 12-pdr guns, QF 2.5-pdr guns, TTs removed later in 1930 and single 8 cm/40 3rd Year AA gun added. Her final armament was just four 12-pdr (3-in/76mm). In 1935 she was drydocked, six Kampon water-tube boilers (7,000 ihp/16 knots) replacing her former large powerplant. This freed space for more bunkerage and extra cadet accomodations/instructor spaces. She had 1,428 metric tons of coal, 329 of fuel oil, and displaced 10,864 metric tons.
On 2 February 1932, she intervened after the first Shanghai Incident, as flagship, 3rd Fleet (Admiral Kichisaburō Nomura). In 1934 she was refitted in Sasebo, receiving a floatplane.
As the Second Sino-Japanese War started by July 1937 she was attacked on 14 August by the Chinese Air Force in the Battle of Shanghai. Two bombs landed among spectators. Izumo’s Nakajima E4N floatplane and another from Sendai claimed to have shot down one Curtiss Hawk biplane and a Northrop Gamma. Her E4N claimed another Hawk afterwards. She was attacked by a Chinese torpedo boat, but torpedoes missed. The TB ws promptyy destroyed. Next, she provided naval gunfire during the battle. Chinese aircraft attacks went on but she had no hit to report, only strafing attacks.
Izumo was still there by 8 December 1941. She captured the USS Wake and gunned, sinsked the HMS Peterel. On 31 December however she hit a mine in Lingayen Gulf while taking part in the Philippines Campaign. Towed to Hong Kong by February 1942 she was repaired, and re-classified as a “1st-class cruiser” by July. By late 1943 she was a training ship in Kure and by 19 March 1945, while off Etajima she was attacked by airplane but only had light damage. He antiquated 8-inch guns were at last replaced by twi twin 12.7 cm (5.0 in) Type 89 DP and her last 6-in guns removed. She received 25 mm Type 96 AA guns (2×3, 2×2, 4×1 mounts) and 2×1 13.2 mm Hotchkiss HMGs. She hit an aerial mine on 9 April off Hiroshima and was near-missed by 28 July 1945. These caused flooding extensive enough to turnover and capsize slowly for most of the crew to survive. Stricken on 20 November she was scrapped in 1947 at Harima Dock. More (TroM)

IJN ww2 Training Cruiser IJN Kasuga (1902)


Part of the Nisshin class purchased to Italy in 1905, this veteran of the Russo-Japanse war and WWI arrived in Portland, Maine for the state centennial celebration on 3 July 1920, visited New York City and Annapolis, Cristobal (Panama) and San Francisco. She carried soldiers and supplies to Siberia in 1922 (Siberian Intervention) under command of Mitsumasa Yonai (future Prime Minister of Japan) and on 15 June 1926 rescued off Japan the crew of the freighter SS City of Naples.
From 1927 she was rerated as a training vessel for navigators and engineers and by July 1928 rescued the crew of airship N3 during fleet maneuvers. By January–February 1934 she carried 40 scientists to Truk for a solar eclipse. Hulked and disarmed by July 1942 she became floating barracks, capsizing at her mooring at Yokosuka on 18 July 1945 after near-misses of an air raid. She was salvaged in August 1948, BU at the Uraga Dock Company. No photo exist to my knowledge of her during the war.

IJN ww2 Hirado(Chikuma) class (1911)

Hirado, Yahagi


Hirado in 1912, note the clipper bow. She apparently never changed appearance in the interwar.
The Chikuma class were two scout cruisers of the IJN, the first of their kind. Fast and moden there were comprehensible restrain to scrap her after the Washington treaty. Her sister Chikuma was sunk as a target ship, 1935, while Yahagi was discarded on 1 April 1940. As for the only one active in 1941, IJN Hirado was assigned to patrol off the east coast of Russia for supply and troop convoys to Siberia, taking her share of service against the Bolshevik Red Army. Her captainw as soon the future Fleet Admiral Osami Nagano (1919-1920) and then Captain Zengo Yoshida until December 1924.
She was tasked to guard the southern approaches to Japan, stopping in Manila and Macau. From 1932 she was reassigned to the northern coast of China and after the Manchurian Incident, based in the Ryojun Guard District (Kwantung Leased Territory). She was plagued all along by engine problems.
Placed in reserve vessel in 1933 she became a training ship, officially stricken on 1 April 1940 but used as the barrack ship Hai Kan No.11 at Etajima Naval Academy and Kure. Towed to Iwasaki in December 1943 she was scrapped postwar, by January-April 1947.

IJN ww2 Tenryu class (1918)

Scout Cruisers Tenryu, Tatsuta


If the great cruisers of the class Kuma, Nagara and Sendai are better known, they constitute an evolution of these precursors, built during the great war. Indeed, the Tenryu and the Tatsuta were defined by the Admiralty in 1916 who wanted a kind of “super-destroyer” based on the British design of the Arethusa and “C”. Under the name of project 33, they were laid down in 1917 two months apart at the Yokosuka and Sasebo shipyards. They had been defined as squadron leaders capable of 33 knots. They also received the new 140mm guns fitted to the two Ise-class battleships. They were also the first to benefit from triple banks of torpedo tubes.

During their long active career (launched in 1918 and completed in 1919), they received a sturdier tripod foremast. Originally, their DCA was provided by a single 78 mm mount, replaced in 1941, after being supported by two 13.2 mm machine guns in 1939, by 5 double 25 mm mounts. The Tatsuta however retained its 78mm on the rear shelf. During the war, they mainly performed escorts. The Tenryu was sunk on December 18, 1942 by an American submersible, the USS Albacore. The Tatsuta survived her only until April 1944, to be torpedoed and sunk in turn by another submersible, the USS Sandlance.

Specifications

Displacement: 3,948 t. standard -4,350 t. Full Load
Dimensions: 142.9 m long, 12.3 m wide, 4 m draft
Propulsion: 3 shafts Kampon SG turbines, 10 mixed boilers, 51,000 hp= 33 kts
Armor protection: From 51 (belt) to 25 mm (Main Deck)
Armament: 4×1 140 mm, 1x 78 mm, 8x 25 mm AA, 2x 13.2mm AA, 2×3 610mm TTs
Crew: 340

IJN ww2 Kuma class (1920)

Scout Cruisers Kuma, Tama, Kitakami, Oi, Kiso


The 6 Kuma class cruisers, of the great armament plan of 1916, entered service too late to participate in the conflict, the last in 1921. They were enlarged versions of the two Tenryu, with a reinforced armament of 3 pieces 140 mm, they were more powerful and faster, but accusing a displacement of 1500 tons higher. They were a compromise between light cruisers and scout ships.

The class included the Kuma, Tama, Kitakami, Oi, and Kiso. Kuma and Tama received seaplanes and a catapult in 1934-35, their rear mast became tripod, the hull was reinforced, the Kitakami seeing its front funnel raised while the others saw themselves grafting different funnel heads. Their foremast superstructures were enlarged. They received four additional 25 mm in 1938-39, and their Torpedo tubes pwere upgraded to 610 mm instead of the initial 533 mm. The displacement thus increased by 200 tons, their speed, initially 36 knots, fell to 33.

Following the very aggressive naval tactics in vogue at the time, the Oi and the Kitakami ferret converted into torpedo cruisers, an old concept fallen into oblivion and refreshed with these versions equipped with 10 quadruple banks of torpedo tubes (40 in total), mounted on 60-meter-long hull side extensions and losing their main artillery. They returned to service in December 1941. Kitakami gained two additional 25mm twin mounts, as well as two 127mm AA twin turrets, and in 1943 she lost four torpedo banks. Severely damaged by the English submarine HMS Templar in 1944, she will be rebuilt as a kaiten transport, losing part of its machinery, replaced by a hold, a crane and a workshop for these eight piloted torpedoes. She survived the war and was BU in 1947, while the Oi was sunk in July 1944, Kiso in November 1944, Tama in October 1944, and Kuma in January 1944.

Specifications

Displacement: 5,650 t. standard -6,200 t. Full Load
Dimensions: 158.6 m long, 14.2 m wide, 4.8 m draft
Propulsion: 2 shafts, 4 Gihon turbines, 12 Kampon boilers, 90,000 hp=32 knots
Armor: 32 to 62 mm
Armament: 7x 140 mm guns, 4x 25 mm AA guns, 4×2 610 mm TTs, mines, 1 aircraft
Crew: 450

IJN ww2 Nagara class (1921)

Scout Cruisers Nagara, Isuzu, Natori, Yuru, Kinu, Abukuma

Isuzu rebuilt in 1944
IJN Nagara:

IJN Isuzu: She was built at the Uraga Dock Company. She was commissioned on 15 August 1923 and participated in the second war with China, covering landings in China, and the capture of Hong Kong. Reassigned to the Dutch East Indies, for the landings and battle of Java, she also later took part later in the Solomon Islands campaign. She was present at the Battle of Santa Cruz and the Naval Battle of Guadalcanal. Almost sunk due to air attacks in late 1943, she headed back to Japan to be rebuilt into an anti-aircraft and anti-submarine cruiser. She participated in the Battle of Leyte Gulf, sunk later by a “wolfpack” of three US submarines and one British, off Sumbawa, 7 April 1945.
IJN Natori:
IJN Natori was built by the Mitsubishi Naval Yard in Nagasaki, commissioned on 15 September 1922. In 1937 and afterwards, she covered troops landings in China and in early 1942, took part in the Phillippines invasion. She also took part in the Dutch East Indies campaigh, notably contributing during the Battle of Sunda Strait, to torpedo the cruisers USS Houston and HMAS Perth. Next she stayed patrolling in the Dutch East Indies waters before a refit and repairs in Japan after air attack in June 1943. She was back in service by April 1944, sunk off Samar by USS Hardhead, on 19 August 1944.
IJN Yura:
IJN Yura was commissioned at Sasebo Naval Arsenal, on 20 March 1923. She was pat of the fleet shadowing Force Z (Prince of Wales and Repulse) in december 1941. Later in January 1942 she covered the landings of Japanese troops in Malaya and Sarawak. She also took part in the Indian Ocean raid, and was part of Nagumo’s escort at the Battle of Midway. She also later took part in the Battle of te Eastern Solomons. Badly damaged after a sever air atack in the Solomons, she was scuttled to prevent capture on 25 October 1942.
IJN Kinu:
IJN Kinu was completed at Kawasaki Shipbuilding Corp., Kobe, on 10 November 1922. She was part of the fiorce shadowing Prince of Wales and Repulse and like her sister Yura also took part in the landings of Japanese troops in Malaya and the Dutch East Indies. She took part in many combat missions in the Solomon Islands and the Philippines. She was ultimately sunk by USN aviation in the Visayan Sea, on 26 October 1944.
IJN Abukuma:
Last of the Nagara class, IJN Abukuma came from the Uraga Dock. She was commissioned on 26 May 1925, part of the escort force assigned to the kido Butai at Pearl Harbor. She was later also the sole Nagara class ship at the Battle of the Komandorski Islands (north pacific), remaining active in northern waters until October 1944. She was rushed south to oppose the American invasion of the Philippines, caught and attacked, severely damaged by ambushing American PT boats, at the Battle of Surigao Strait (25 October) finished off by land-based bombers and eventually scuttled on 26 October 1944.

Interwar IJN cruisers

IJN ww2 Sendai class (1923)

Light Cruisers Sendai, Jintsu, Naka +5 cancelled


The cruisers of the Sendai class were very close in their general design compared to the previous Nagara, but with larger dimensions, new machinery for greater speed traduced in a new funnel. The fourth of the class, 1st batch, IJN Kako, was broken up soon after launch, as the following 2nd batch because of the Washington Treaty limitations, just signed.
The three cruisers received a catapult for reconnaissance in 1929, and by 1943, a powerful AA. All were sunk in action, Naka in February 1944 during the air raid on Truk, Sendai by aviation after the Battle of the Bay of Empress Augusta, and Jintsu by gunfire at the battle of Kolombangara.
Specifications
Displacement 5,200 t. standard 7,100 t. Fully Loaded
Dimensions 163 x 14,17 x 5m (532 x 46 ft 6 in x 15 ft 9 in or 29 ft FL)
Propulsion 2 shafts, 4 Gihon turbines, 12 Kampon boilers, 90,000 hp, 154kW 110V electrical
Speed 35,2 knots (65.28 km/h; 40.56 mph)
Range 5,000 nmi (9,300 km; 5,800 mi)/14 knots (oil 1010 tons, coal 570 tons)
Armament 7x 140mm/50, 2x 76mm, 2x 13.2mm AA, 4×2 610 mm TTs, 1 seaplane, 80 mines
Protection Armor scheme – 28 to 65 mm, see notes
Crew 450 (1925)

IJN ww2 IJN Yubari (1924)

Light cruiser

yubari
IJN Yūbari (夕張) was not only the very first IJN post-WW1 design, but it was an experimental light cruiser whose idea dated back from 1917 and started in 1922, and when she was completed in 1923 for the Imperial Japanese Navy, she marked a large step forward in the nation’s cruiser design. Designed by famous engineer Yuzuru Hiraga, she was largely seen as a test bed for new designs and technologies in a post-Washington Naval-treaty, tonnage restrictive environment. Nevertheless, she was commissioned and had a quite active career in many operations during the Pacific theatre of WW2. Yūbari’s designs and innovation would find their way into many future IJN warships, from destroyers to cruisers. During the war, she took part in the most vicious fights in the South Pacific, notably participating in the whole Solomons campaign, from beginning to the end at Rabaul in 1944. She was commanded from 1940 to 1942 by captain Masami Ban, and until 1943 by Taiji Hirai, before in 1944 being handed to Morie Funaki until 1944 and finally, to Takeo Nara for two months of her life.
Specifications
Displacement 3,315 t. standard -4,447 t. Full Load
Dimensions 139 m long, 12 m wide, 3.6 m draft
Propulsion 3 shaft turbines and 8 boilers, 57,500 hp, 34 knots
Armor: Armored Deck and belt 16-22-25-28 mm, gun shields 11 mm, ammo wells 32 mm
Armament: 6x 140 mm (2×2, 2×1), 1× 76mm/40 AA, 2×2 610 mm TTs, 2x 7.7mm MGs, 34 mines.
Crew: 350

IJN ww2 Furutaka class (1925)

Light cruisers Furutaka, Kako


The first Japanese “washington” cruisers, were also two “heavy cruisers”. The Furutaka class were the first built by the Japanese Navy after the Washington Treaty. Their main feature was the presence of a continuous deck with two successive recesses, a measure to save weight to optimize speed, but also the choice of an artillery in six simple turrets.
This singular configuration did not proved advantageous and the two ships were rebuilt in 1936-39. Significant changes included the more rational choice of double turrets, reconstructed superstructures and bridge, and lateral torpedo tubes. 12 tubes, 6 twin banks two on each side replaced by two quadruple banks.

A catapult was also fitted, as well as the installation of anti-torpedo ballasts, the reinforcement of the overall protection and the AAA, with a tonnage passing from 7,100-8,450 tons to 8,700-10,340 tons. Originally, this AA artillery consisted of only four 100 mm pieces and two heavy machine guns. In 1932 these were replaced by QF 120 mm fully shielded in half turrets, while 25 mm guns and other heavy 12.7mm machine guns were added to this range.

By the new standard they imposed, the Furutaka led to the Aoba, barely larger, but improved. They participated very actively in the Japanese operations, particularly in the Solomon Islands, and were both sunk, the Furutaka off the island of Savo, Guadalcanal, during the battle of Cape Hope the night of October 11 to 12, 1942, being part of the “Tokyo Night Express”, by the American cruisers of Admiral Scott. The Kako was torpedoed and sunk near Kiaveng (New Britain) by the old American submarine S44, August 10, 1942. She participated shortly before the great victory at Savo Island.
Specifications
Displacement 8 700 t. standard -10 340 t. FL
Dimensions 183,53 x 19,93 x 5,61m
Propulsion 4 shafts turbines, 12 boilers, 102,000 hp, 33 knots
Armor: 25 to 76 mm
Armament: 6x 152 (3×2), 4x 120, 8x 25 AA, 4x 13.2 mm HMG AA, 8x 610 mm TTs (2×4), 2 seaplanes
Crew: 730

IJN ww2 Aoba class (1925)

Heavy Cruisers Aoba, Kinugasa

Aoba on trials
The two Aoba-class heavy cruisers followed the Furutaka a year apart, so their development did not take into account the shortcomings of the two previous ships. They had from the start three twin turrets and twin 5-in DP guns. On the other hand, their torpedo tubes were still two triple fixes per side. A first modification intervened in 1932: They received four twin 13.2 mm (0.5 in) cal. HMGs. By 1938-40, their fixed tubes were replaced by two quadruple banks on deck, and to compensate for stability (and future upgrades), they were fitted with side ballast tanks. Their AA was reinforced with 25 mm cannons, four more heavy machine guns, bringing the total to 12.

In operations, the two ships were seen in all major operations. Particularly active in the Solomons, they notably participated in the “massacre” of Savo Island on the night of August 8, 1942. IJN Kinugasa was sunk by USN aviation on November 14, 1942 during the second Battle of Guadalcanal, while Aoba survived long enough to see her armament increase to fifteen 25 mm AA guns, then forty-two two months later in May-June 1944. She received a radar but the two banks were removed. She saw the Battle of the Coral Sea, the first Battle of Guadalcanal, and second, and was destroyed eventually by the US III Air Fleet while moored in Kure Naval Base, on July 25, 1945.

Specifications

Displacement: 7100 t. standard -8760 t. Full Load
Dimensions: 183.58 m long, 15.83 m wide, 5.71 m draft
Propulsion: 4 shafts Kampon Steam turbines, 12 boilers, 102,000 hp, 34.5 knots
Armor: 25 to 76 mm (2-3 in)
Armament: 3×2 6-in(203mm), 4x 120mm, 8x 25 AA, 4x 13.2 mm AA, 6×2 610 mm TTs, 1 aircraft
Crew: 625

IJN ww2 Nachi class (1925)

The Nachi: First true IJN heavy cruisers

The heavy cruisers of the Nachi class laid down between 1924 and 1925 and completed in 1928-29, were at the very limits of the Washington Treaty, yet they managed to bear a five turret arrangement never seen on a ship of this type before, and imposing to the IJN new standard, not followed internationally but coherent with Japanese retirement of the league of nations.
This feat consisted of being able to stack five twin turrets for 8-in/203 mm guns and 12 torpedo tubes on a cruiser more than 200 meters long, but which ultimately displaced only the 10,000 tons required by the treaty. They could reach 35.5 knots without excessive power either. The secret laid partly in their amazing width/lenght ratio almost unchanged from the Aoba, about the same 12/1. Their protection was greatly improved however with an inner armoured citadel ad a triple hull plus reinforced coss-sections and a reduced but reinforced bulkhead. In fact, the final tonnage as for 1941 was 11,000 tons.

IJN Ashigara an the Gref Spee in the background at Kiel in March 1937. Colorized photo by Hirootoko JR.

1930s et 1940s refit

In 1934-36, their single 120 mm single mounts gave way to new 127 mm (5 in) twin turrets, their fixed torpedo tubes replaced by quadruple rotating banks, while the AA was reinforced by four additional 13.2 mm machine guns and two catapults were installed on the sides to launch reconnaissance floatplanes. In 1940-41 there was a second overhaul concerning the masts and superstructures, the addition of 8 x 25 mm AA guns and especially two new quadruple torpedo tubes on the flanks, for a total of 16, a record for a cruiser, but in the typical trend of aggressiveness of the Japanese tactics at the time. This forced to add imposing bulges in order to safeguard their stability.
IJN Nachi in Yokosuka in the 1920s
IJN Nachi in Yokosuka in the 1920s. Colorized photo by Hirootoko JR.

Specifications

Displacement 13,000 t. standard -14,740 t. Full Load
Dimensions 203.76 m long, 20.60 m wide, 5.66 m draft
Propulsion 4 propellers, 4 turbines, 12 boilers, 130,000 hp.
Top speed 34 knots
Armour from 100 to 25 mm
Armament 10 guns of 152 (5 × 2), 8 guns of 12, 8 of 25 AA, 12 mitt. 13.2 mm AA, 16 TLT 610 mm (4 × 4), 3 aircraft
Crew 773

The Nachi class in action

In operations, these four ships, the IJN Nachi, Myoko, Ashigara and Haguro proved formidable combatants, very actively employed, and which defeated all their American, British and Dutch opponents until 1943. The Myoko was apparently the only one to have been camouflaged. These Nachi class cruisers participated in the battle of Leyte, where the Nachi, in the confusion and fury of the attacks, collided and seriously damaged the Mogami.
Shortly before this battle, their AA armament had reached fifty-two 25mm guns, at the cost of removing two banks of torpedo tubes. They survived the battle of Samar (Leyte), the Nachi being sunk in November 1944 off Manila by USN air attacks, while IJN Myoko, already badly damaged in Leyte, was torpedoed by USS Bergall in December 1944 but survived.
She sank in shallow waters in the Strait of Malacca, and her wreck was dynamited in 1946 to allow trade to resume. IJN Haguro and Ashigara were sunk respectively in May and June 1945, one by the torpedoes of British destroyers off Penang during the reconquest of Malaysia, while the second was torpedoed by British submarine HMS Trenchant in the Bangka Strait.
Myoko 1944 - author's schematics
Myoko 1944 – author’s schematics
Myoko
Cruiser Myoko on sea trials in March 1941 in Sukumo Bay. Colorized photo by Hirootoko JR.

IJN ww2 Takao class (1930)

Heavy Cruisers: Takao, Atago, Maya, Chokai

takao class
The Takao class of heavy cruisers, laid down in 1927-28, launched in 1930 and completed in 1932, comprising the Takao, Atago, Maya and Chokai were among the best and most active Japanese cruisers of World War II. They derived from the Nachi, from which they took over the essentials, with however better protection, including their armored decks, an increase in the main parts and banks of quadruple rotating torpedo tubes from the outset. Moreover, their standard displacement was even lower than the Nachi, at 9,850 tons instead of 10,000, which compared to comparable American cruisers was exceptional. They put their excellent provisions to the test of fire and resisted very well the impacts of American buildings during the hard engagements of 1942-44. Their footbridge was notably very different from the Nachi, affecting much fuller and more solid forms, very characteristic with their three superimposed footbridges.

In 1939-40, Takao and Atago received two additional quadruple banks of torpedo tubes, bringing the total to 16, received side ballast tanks, and the doubling of their secondary artillery, including the addition of 8 x 25 guns. mm YY. Their original measurements were 201.67 meters long by 18 wide and 6.11 draft for 12,780 tons fully loaded. Compare with their 1941 file. Chokai and Maya, on the other hand, received neither the additional torpedo tube banks nor the 25 mm guns. On the other hand all saw their AA artillery increase considerably. On the eve of the titanic battle of Leyte, they had 60 to 66 25 mm AA guns.

In operations, these four ships were the spearhead of the Japanese Navy, participating in most important engagements. All four were engaged in Admiral Kurita’s shock squadron under Toyoda during the Battle of Leyte in October 1944. The squadron was spotted on October 21 by American submersibles, and attacked on the evening of the 23rd. by the USS Darter and Dace, confirming their presence. They torpedoed and sent the Atago and the Maya to the bottom. The Darter then went after the Takao, who survived three shots on goal and barely made it back to Brunei, before heading to Singapore for further repairs.

Finally, Chokai, the same day, was taken to task by the American naval aviation, hit by several bombs from the Curtiss Helldivers, it was finally disabled and attacked by the American destroyers who opened fire at close range and finished it off. The Takao therefore escaped the battle of Samar and was repaired but condemned to inaction in the harbor of Singapore. She was sunk on the spot by the British Navy commandos using the pocket submersible XE3, who placed charges against her hull, on July 31, 1945. An operation which was the subject of a film. In October 1946 she was refloated, towed and laid up in the Strait of Malacca.
Specifications
Displacement 13,400 t. standard -14,600 t. Full Load
Dimensions 203.76 m long, 20.73 m wide, 6.11 m draft
Machines 4 propellers, 4 turbines, 12 boilers, 130,000 hp.
Maximum speed 34.2 knots
Armor From 130 (magazines) to 25 mm
Armament 10 x 203mm guns (5×2), 8 x 127mm guns (4×2), 8 x 25mm AA, 6 mitt. 13.2 mm AA, 8/16 TLT 610 mm (2/4×4), 3 aircraft
Crew 773

IJN ww2 Ioshima class (1937)

Light Cruisers Ioshima, Yashoshima


The Ning Hai class cruisers were the culmination of many “firsts” and “lasts”: First cruisers of the feldgling Chinese Republic, first built in Japan, and last Chinese cruisers overall (although arguably the new Type 055 missile destroyers of the actual PLAN us locally called Renhai-class cruiser). The Ning Hai were in fact the only cruisers built for the Chinese Navy since the fall of the Empire in 1911, followed by a first repulic, the warlord era, and a more or less stabilized republic again, allowing to plan a modenrization of the fleet. Indeed in 1937, at the time of the start of the second Sino-Japanese war, after a quasi-war in the north since 1932, the Chinese Navy was in dire straits, with on paper a fleet of cruisers and gunboats dating back from twenty years and more.

They had received little modifications between them and were hopelessely obsolete and outmatched by the IJN. Both ships had a very short career under Chinese flag, both were sunk in the Yangtze River on 23 September 1937, by Japanese aviation. They were refloated and later repaired by the Japanese, and pressed into service in the IJN where they spent the rest of their career. Originally planned for transfer to the puppet government of Wang Jing-Wei, they were outfitted as barracks hulks and later the escort ships IJN Ioshima and Yasoshima, in 1944. Both were lost in action to USN torpedoes the same year.

Specifications (as Yasoshima class 1942)
Dimensions 109.7m oa x 11.9m x 3.96m
Displacement 2165 standard, 2500 tons FL
Propulsion 2-3 shafts 2/3 VTE, 4/2 Kampon boilers, 9,000 hp
Speed Top speed 22.2 knots (25 mph; 40 km/h)
Range 5,000 nmi (9000 km) at 12 kn
Armament 2 x 1 – 120/45 10-shiki, 5 x 3 – 25/60 96-shiki, 2 DCR (18)
Electronics 2-shiki 2-go radar, 93-shiki sonar
Armor belt 2-in (25 mm), Deck 2.8 in (19 mm)
Crew 340

IJN ww2 Mogami class (1937)

Light Cruisers: Mogami, Mikuma, Suzuya, Kumano


Mogami at Kure in July 1935 trials

The Mogami class cruisers (Mogami, Mikuma, Suzuya, Kumano), launched in 1934 (1936 for the Kumano) and completed in pairs respectively in 1935 and 1937 at the Kure, Mitsubishi (Nagasaki), Yokosuka and Kawasaki (Kobe) shipyards, suffered delay resulting from the tests carried out with the first two, which were victims of vibrations due to the structural weakness of their hull, so bad that the turrets were unusable. The last two were therefore overhauled and reinforced, receiving ballast for their stability, while the first two went back to drydock in 1936-38 for the same modifications. They were classed as light cruisers due to an initial standard displacement of 8,500 tons, 15 x 155mm guns in five triple turrets like contemporary Brooklyn class and capable of 37 knots. However, by their dimensions, they were more similar to heavy cruisers.

In 1939, they displaced 11,200 tons as standard, or 3,700 tons of various reinforcements. During a second series of modifications at Kure in 1939-40, they became real heavy cruisers, their 155 guns being abandoned in favor of an armament of 5 twin 203 mm turrets. Their width increased and their protection was further improved. Their AA artillery, initially composed of 8 double turrets of 127 mm and 4 pieces of 40 mm passed to 20, then 30 guns of 25 mm AA, and finally 50 for the survivors on the eve of the battle of Leyte. Always with the aim of safeguarding stability, their torpedo tube mountings were triple and not quadruple, but there were always 4 of them. come.

IJN Mogami and Mikuma were engaged in the Battle of Midway in June 1942 under the command of Admiral Yamamoto. But this time luck had changed sides, and the two ships were seriously damaged, first in the confusion of the night, by a serious collision on June 6, 1942, at 2:15 a.m., then around 5 a.m., when the The Admiral had ordered the withdrawal of the fleet, by the US Navy’s SBD Dauntless dive bombers. The Mikuma did not survive and sank, while the Mogami was also attacked later that day. It survived there and dragged itself to Kure for year-long refits. We took the opportunity to rebuild it into a hybrid aircraft carrier, capable of carrying 11 seaplanes, including torpedo planes, and A6M2N Rufe fighters, in order to provide cover to the squadrons. In 1943, he returned to service with a DCA composed of 30 25 mm guns in fifteen double mounts.

This reconstruction had inspired the Admiralty who decided to order the construction of two buildings of the same type, the Ibuki class, but only one of which was completed, and as a fast aircraft carrier. The Mogami was engaged in the Battle of Surigao Strait shortly after, and was there on this occasion manhandled by the fire of the American cruisers. All three (Mogami, Suzuya and Kumano) were also present during the Battle of Samar near Leyte in the Philippines in October 1944. The Mogami sank on October 25, completed by Grumman TBM Avenger torpedo bombers. The Suzuya was also doomed to the same end, while the Kumano survived it. He tried to flee from patrols for a month and was finally spotted and bombarded by other aircraft on November 25, exactly one month after his twins went missing. The last one, Ibuki, was converted into a fleet aircraft carrier, but never completed.


Specifications
Displacement 12,400 t. standard -13,670 t. Full Load
Dimensions 201 m long, 20.50 m wide, 5.9 m draft
Machines 4 propellers, 4 turbines, 12 boilers, 152,000 hp.
Maximum speed 35 knots
Armor From 130 (magazines) to 250 mm
Armament 10 guns of 203 mm (5×2), 8 guns of 127mm (4×2), 2 guns of 40 and 20 of 25 mm AA, 6 mitt. 13.2 mm AA, 12 TLT 610 mm (4×3), 3 aircraft
Crew 850

IJN ww2 Tone class (1939)

Hybrid Cruisers: Tone, Chikuma


IJN Tone, May 27, 1942
The Tone-class cruisers (Tone and Chikuma) were part of the 1932 supplemental plan to include light cruisers under the terms of the Washington Treaty, but in 1938-39, with the approach of hostilities, it was decided to terminate them as cruisers heavy. Their triple 155 mm turrets were not retained and they were reinforced considerably. However, their great originality lay in their hybrid nature, with all their pieces concentrated in the hunt (at the front), leaving their aft deck free of any accommodation intended to operate squadrons of reconnaissance seaplanes.

After modifications, changing to four twin 203 mm turrets, they still remained as powerful as the standard heavy cruisers in service in the world. They were to be used as scout cruisers and inspired the reconstruction of the Mogami in 1942. However, they did not have a real large hangar and therefore could only operate 5 to 6 seaplanes. Their anti-aircraft artillery initially consisted of 12 25 mm guns in six double mountings, then it quickly increased to 30 at the start of the conflict. The Tone ended the war with 57 25 mm guns, which did not prevent her from being sunk.

IJN Tone was at Midway in June 1942, then participated as her twin in the Battle of the Eastern Solomons in August 1942, from the Santa Cruz Islands, in the second battle of Guadalcanal in November 1942. The Tone and the Chikuma were finally engaged in the battle of Leyte in October 1944, under the command of Admiral Kurita. The Chikuma suffered attacks from US Navy aircraft and sank on October 25. The Tone survived there, but it was only to perish under the bombs of other planes in the bay of Kure during the great raids of the III Air Force on July 24, 1945. It was plasticized and its remains desoldered in situ in 1948.


Specifications
Displacement 12,400 t. standard -15,200 t. Full Load
Dimensions 201.5 m long, 18.50 m wide, 5.9 m draft
Machines 4 propellers, 4 turbines, 12 boilers, 152,000 hp.
Maximum speed 35 knots
Armor From 130 (magazines) to 25 mm
Armament 8 x 203mm guns (4×2), 8 x 127mm guns (4×2), 30 x 25mm AA guns, 12 x 610mm TLT (4×3), 5 aircraft
Crew 850

IJN ww2 Katori class (1941)

School Cruisers: Katori, Kashima and Kashii

kashima yokohama 1940
The three units of this class, Katori, Kashima and Kashii, were designed as training cruisers, and base buildings for destroyer and submarine flotillas. Short, wide, slow, and under-armed, they were of low military value but were nevertheless engaged in combat with an increased armament, including three twin turrets of 76 mm AA, and 25 25 mm guns, the tubes torpedo boats being landed. It was further increased by 5 pieces of 25 mm AA and various heavy machine guns, the catapult being in turn dismounted. Katori, damaged near Truk Naval Air Station, was completed by US Navy units in April 1944, Kashii torpedoed and sunk by an Avenger in the China Sea in January 1945, and Kashima survived the war, BU in 1947.


Specifications
Displacement 5,890 t. standard -6,500 t. Full Load
Dimensions 129.77 m long, 15.96 m wide, 5.75 m draft
Machines 2 propellers, 2 turbines, diesel engines, 3 boilers, 80,000 hp.
Maximum speed 18 knots
Bridge shielding 50 mm
Armament 4 x 140 guns (2×2), 1×2 x 76 guns, 4 x 25 mm AA, 4 x 533 mm TLT (2×2), 1 aircraft
Crew 160+200 students

IJN ww2 Agano class (1941)

Light Cruisers Agano, Noshiro, Yahagi, Sakawa

The last IJN light cruisers


Blueprint Agano 1942
The Agano were the last Japanese light cruiser built in serie, and the fourth of the class, IJN Sakawa, was completed in December 1944, as the very last Japanese cruiser as after the war, shipyards only delivered “destroyers”. This Class included the Agano, launched in 1941 and completed in 1942, Noshiro and Yahagi, launched in 1942 and completed in 1943 and finally the Sakawa, launched in 1944, due to various delays. Classified as light cruisers, they were part of an extensive program to replace older cruisers such as the twenty-year-old Kuma, Nagara and Sendai classes. The Agano, as it appeared at its entry into service.
They were also planned as destroyers leaders. They were therefore light but fast at 35 knots, with a reconnaissance capability (two seaplanes), and yet still an armament able to cope with enemy destroyers. They added a large AA battery composed of 25 mm in single, twin, triple mounts for up to 61 on Sakawa in 1945. Three were sunk in action, Agano in February 1944, Noshiro in October 1943, Yahagi (rearmed with 52 guns i 1944) in April 1945. IJN Sakawa survived the conflict, but was quickly integrated into the small fleet gathered in Bikini Atoll to be blasted at the July 2, 1946 “Able” nuclear test.


IJN Agano
Agano 1942 – Author’s HD profile illustration
IJN Agano
Author’s profile illustration Yahagi 1944

Specifications

Displacement 6,550 t. standard -8,530 t. Full Load
Dimensions 174 m long, 15,20 m wide, 5,63 m draft
Propulsion 4 shaft, Kampon turbines, 6 boilers, 100,000 hp.
Top speed 35 knots
Armor from 50 to 85 mm
Armament 6 x 152 (2 × 3), 4 x 100 (2 × 2), 32 x 25 AA, 16 DCT, 8 x 610 mm (2 × 4) TTs, 2 seaplanes
Crew 730

IJN Agano: Completed on 31 October 1942, she took part in the Guadalcanal Campaign and Solomon Islands battles of 1943. IJN Agano however was badly damaged in Rabaul durring a US air strike, hit by the air groups from USS Saratoga and Princeton. Later, still in repairs there, she was attacked again by aicraft from TF38 on 11 November, receiving a torpedo hit. While underway for home island and drydock repairs, she was ambushed, torpedoed and sunk north of Truk, by USS Skate (SS-305) on 16 February 1944.
IJN Noshiro: She was Commissioned on 30 June 1943, seeing the Solomon Islands Campaign but damaged during the USN raids on Rabaul, on 5 November 1943. Back in the Marianas in the summer of 1944 she took part in Admiral Kurita’s force bold sweep at the Battle of the Philippine Sea. She was sunk at the Battle of Leyte Gulf in October 1944. She sailed west of Panay while withdrawing from Samar, when spotted on the morning of 26 October by aircraft from USS Wasp and USS Cowpens, strafed, bombed and eventually sunk on 26 October.
IJN Yahagi: She was Commissioned on 29 December 1943, seeing action in the Marianas Islands in May and June 1944. She took part in the Battle of the Philippine Sea in june, and the Battle of Leyte Gulf in october, but survived both. While the invasion of Okinawa was taking place, she was assigned to a desperate task forced centered around IJN Yamato on 1 April 1945, a suicide mission against the amphibious fleet off Okinawa. The task force was spotted en route and IJN Yahagi was caught by multiple air groups, hit by some seven torpedoes as well as a dozen bombs, leving her no chance. She sank in the afternoon, 7 April 1945.
IJN Sakawa: Completed at the end of 1944, little fuel available, IJN Yahagi was practically inactive, so her crew had plenty of training when she was used for a few sweeps along the coast, exchanging fire on some occasions with passing by US planes. She survived the war. Used as a transport to return demilitarized troops from New Guinea and ther islands until took on the disposal list by the US, she was seized and pressed into the atom bomb tests at Bikini Atoll, in 1946.

IJN ww2 Oyodo class (1942)

Light Cruisers Oyodo, 8 more planned (cancelled)

She was one of the last cruiser of the Empire, the very last being the fourth Agano class. Initially designed as a hybrid scouting cruiser on the same principle as IJN Tone, yet lighter, cheaper and faster to build, she was tailored to carry and operate specifically six Kawanishi E15K long-range seaplanes, fitted with a 45-meter (147 feet) long aft catapult, to screen forward of oceanic submarine fleets.

Her armament comprised two triple 6-in guns (155 mm) at first, same as the Mogami-class, but as the war progressed, she was rearmed with two surplus twin 8-in turrets, so just four in all. At her completion in February 1943, planned long range operations, notably against the Panama Canal by large Japanese carrier submersible were very compromised. Also, her own planned seaplanes were still not operational. The admiralty decided to fit her instead a more standard catapult and standard model floatplanes. The large hangar was no longer used, and she operated with just two aircraft.

Due to her reduced military value, IJN Oyodo saw little fighting. Twelve ships of the same class were initially planned for the 1939 and 1942 naval plans, none being built, or even laid down. IJN Oyodo received a better AA as the war progressed: In in 1945 this went up to fifty-two 25 mm AA in triple, twin or single mounts. This did not prevented her eventual fate: In 1945 she was anchored in kure, short of fuel, when USN aviation straddled then sank her in the harbor, on July 28, 1945. As the the last survivors of the Imperial Navy’s cruiser, she was broken up after the war, but the modern JMSDF took inpiration of her for large ASW helicopter desoroyers of the 1970-90s.

IJN Oyodo
Author’s profile illustration Oyodo 1944
Displacement 8,164 t. standard -10 252 t. Full Load
Dimensions 192.10 m long, 16.60 m wide, 5.9 m draft
Machines 4 propellers, 4 turbines, 6 boilers, 110,000 hp.
Top speed 35 knots
Protection 50 to 25 mm
Armament 6 x 155 mm (2 × 3) guns, 8 x 100 mm (4 × 2) guns, 12 x 25 mm AA guns, 2 planes
Crew 600

IJN ww2 Ibuki class (1944)

Light Cruisers Ibuki, Ikoma, +2 unnamed.


IJN Ibuki being scrapped in 1947

The Ibuki-class (伊吹型) cruisers were the last Japanese heavy cruisers and to gain in design time, they were essentially repeats of Mogami class. The lead ship IJN Ibuki was the only one advanced enough to be launched, but after Pearl Harbor it was decided to convert her into a light aircraft carrier. However this progresses slosly until she was suspended in 1945, and scrapped the following year. The -still unnamed- “N°301” was scrapped a month after being laid down to clear the slipway and start a new aircraft carrier.
This will be the object of a dedicated post in the future.
Specs:
12,220/14,828 t FL, 200.6 x 20.2 x 6 m (658 ft 2 in x 66 ft 3 in x 19 ft 10 in). 4 shafts GST, 8 Kampon WT Boilers 152,000 shp (113,000 kW) =35 knots RA 6,300 nmi/18 kts, Crew 876. One Type 2, Mark 2, Model 1 air search radar and Type 93 hydrophone system as planned, 5×2 8 in, 4×2 5 in DP, 4×2 1 in AA guns, 2×2 0.52 in Type 93 HMGs, 4×4 24 in TTs, 2 catapults, 3 floatplanes.
Armor belt 1.2–5.5 in, Deck 1.4–2.4 in, turrets 1 in, Barbettes 1–3.9 in CT 4 in

As converted as an aircraft carrier, 1945 Specs as an aircraft carrier

Projected Cruisers

Combining the interwar and WW2 there were many alternative designs. However given the systematic destruction of archives at the end of WW2, there are not many around to gaze and discussed upon.
Let’s cite the following, for which at least some data is known:
Light Cruisers Design C-19 (1912) Primary minelayer cruiser design before WW1, not voted or ordered. Dimensions 159,41 (pp) x 15,24 x 5,18 meters, displacement 6.000tons (standard) prop. 2 shafts GST 28.500shp, 27 kts, RA 18.500km (10.000nm). Same armament as the Tenryu and 100 mines.
Light Cruiser Design C-31A (1915): Wartime design, well armed cruiser preliminary to the Tenryu class and proposed 1914 large scout cruiser.
Dimensions: 161,54 (pp) x 15,85 x 5,1 m for 7.000tons, 4 shafts GST 106.000shp, 35 kts, RA 9.200km (5.000nm), protected by 25mm Deck, 76mm Belt and armed with nine single shielded 140mm Guns (repartition unknown) and triple 533mm TTs, 48 mines.
Light Cruiser Design C-32 (1915): Smaller, leading to the Tenryu design: 140,21 (pp) x 13,41 x 4,11 m for 4.100tons, 4 shafts 65.000shp 34 kts and 11.000km (5.900nm), protected by 25mm Deck, 63mm Belt and armed with 5×1 140mm and 2×3 533mm TTs, 48 mines.

Armoured Cruiser of 7.200 ton Proposal (1916) The last IJN armored cruisers ever, although still doubling as scout cruisers. Planned in 1914 but slow construction timetable delayed them to 1916 and the design was reformulated to three 7.200 ton cruisers as part of the 8-4 and 8-6 naval programmes. Never built but considered as very early steps in the Furutaka class since the 20cm guns were considered for them. Displacement 7.200tons, 36 kts and RA 11.000km (8.000nm), prot. 51mm Deck, 76mm Belt, four twin and a single 140mm Guns, four twin 610mm TTs

Light cruiser Tenryu-Kai type (1917): 6 modified or improved Tenryu class cruisers were considered to be built from 1917 onward as part of the 8-4 and 8-6 naval programmes. Their designer was Teiji Kawase and only very limited info I could gather was that it’s displacement would be 3.500tons compared to 3.230tons of the Tenryu class which indicate more armour somewhat more armament and larger 610mm torpedo tubes with the associated increased engine power.

Furutaka Class original Design (1918): The design process eventually leading the creation of the Furutaka class Heavy Cruisers was first started with a smaller ship evolved from the previous 7.200ton design to 8.000tons and 5-6 twin 140mm guns in a pyramidal arrangement while the AA armament only consisted of 2 single 76mm guns while the torpedo armament unchanged from the 4 twin 610mm tubes. Armour wise it was much thinner as well with the armoured box protecting only the machinery by 64mm belt and 25mm deck. Eventually based on the data of the USN’s Omaha class but especially on the British Hawkins class, this design evolved into the IJN’s first heavy cruiser type.

Tenryu-Kai type (1921): A different source provides more data on the Tenryu-Kai type cruiser putting it to 1921 and with somewhat more displacement. Dimensions 143 (oa) x 12,4 x 4 m for 4.080tons, 3 shafts GST 51.000 shp 33 kts and 11.000km (8.000nm), prot. 25mm Deck, 63mm Belt, 2×2 140mm, 1x 76mm AA, 2×2 610mm TTs.

Heavy cruisers Design C-41 (1923) From Yuzuru Hiraga perosnal archives, very early Nachi class design. Their armament was weak compared to the tonnage, so they probably would have been brushed aside by the admiralty. More
Dimensions: 225,5 (pp) x 21,64 x 5,33 meters, Displacement: 14.000 tons (standard) 18.000 tons (Full load). Prop. 4 shafts GST 140.000shp 36.5 kts
Armour: 25/47mm Deck, 51/102mm Belt (Magazines/Machinery)
Armed with 4×2 200 mm/50 Type 3, 2×1 120mm/45 Type 10 DP, 2×4 610mm TTs.

Heavy cruisers Design C-42 (1923) Another, same initial design process, smaller and slower but armed the same way and better protected:
Dimensions: 210,3 (pp) x 20,11 x 5,26 meters, Displacement: 12.000 tons (standard) 15.200 tons (Full load), 4 shafts GST 125.000shp 36 kts, RA 14.800 km (8.000 nm)
Armour: 25/47mm Deck, 51/102mm Belt (Magazines/Machinery)

Nachi Preliminary Design (1924): Singular with their well armoured triple and quadruple turrets, slightly shorter hull, thinner armour
Dimensions 198,12 (pp) x 17,52 meters, displacement: 10.000tons (standard), prot. 38mm Deck, 89mm Belt, armed with 4×3/3×4 200mm/50 Type 3, same as above.
Nachi Preliminary Design 3 (1924): Same but longer range, 5×2 200mm/50 Type 3 Guns

Squadron leader Design C-43 (1923): Proposal found in the Yuzuru Hiraga archive but likely Hiraga’s own design number because C-42 was Oyodo and C-44 was the Agano-Kai. Might be connected to the earlier 5.600ton design. Source
Dimensions: 152,4 (pp) x 14,17 x 4,85 m for 5.600tons (standard) 7.000tons (Full load). Prop. 3 shafts 42.750 shp GST, 35 kts RA 9.200km (5.000nm). Only deck prot. (machinery) 25 mm Deck and 64mm Belt. Armed with 4×2 140 mm, 2×1 76mm DP-AA Guns, 2×2 610mm Torpedo Tubes, 100 Mines.

Light cruiser 5.000 ton Proposal (1926): A well armed true light cruiser on limited displacement and average speed, it’s origins are a mystery but might be connected to the numerous Vickers export designs of the time. src https://iiif.dl.itc.u-tokyo.ac.jp/r…3d88f#?c=0&m=0&s=0&cv=0&xywh=-659,0,8261,4927
Engines: 60.000shp Steam Turbines, 4 shafts, speed: 59km/h (30,5knots)
Armaments: 3×3 152mm, 2×2 120mm DP-AA, 2×2 533mm Torpedo Tubes

Design 1927/C-37 (1927): Earliest proposal in the design linage leading to the Mogami class cruisers.
Dimensions: 197 m wl, Displacement: 8.500tons (standard) 11.200tons (Full load). 4 shafts GST 152.000 shp. Armour: 38mm Deck, 125/143mm Belt (Magazines/Machinery). Armed with 5×3 155mm, 4×1 127mm DP-AA, 4×3 610mm TTs, 2x Scout Planes

Squadron Leader Design (1928): Early light design which led years afterwards to the Agano and Oyodo class. Good speed as lead/scouts for destroyers. 6 planned but cancelled (Four Takao-Kai type planned instead by 1930. Lacroix mentioned they were to be armed with six 50-cal 14-cm guns in twin mounts and high elevation, type planned for the Kongo Replacement designs of 1928-29. So Displacement 5.000tons, prop. 3 shafts GST 42.750 shp 35 kts RA 9.200km (5.000 nm). Armour: 51mm Deck, 76mm Belt, armed woth 3×2 140mm/50 Type 3/140mm/55 Type 88 Guns, 2×3 610mm TTs, 2x Scout Planes

Takao-Kai type Heavy Cruisers (1929): Follow-up design postponed due to the Treaty of London. It is conjectured they had a better heavy AA and improved armour (like 140mm Magazine belt) and the same 5 twin turrets but ported on the new new /55 in development. Mogami style smaller Tower bridge. Probably 12,000 tonnes (10.000 declared).

Tone-Kai type Heavy Cruiser (1938/39) – At the 1938 revised Maru 4 programme, two modified Tone type cruisers were considered to be built to form a homogeneous squadron with the other two Tones. Not much is known about this design except that it was based on the Tone class but with substantial more displacement of 13.000tons standard instead of the 11.200tons of the original Tones which might indicate better armour and engine power and command facilities.
Source: (Eric Lacroix – Japanese Cruisers of the Pacific War), Japanese Wiki
https://ja.wikipedia.org/wiki/改利根型重巡洋艦

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IJN Haguro upgun proposal (1933): New 8-in cannons under development comparable to the USN 8″/55 cannons to be first tested on IJN Haguro and ported on the remainder Takao class ships. Budgetary constraints stopped the development.

Squadron Leader Design (1937) -Earliest precursor of the Agano class, on smaller displacement and Oyodo’s armament, heavy AA. Five ships planned (Maru 3 programme) but not voted.
Displacement: 5.000 tons (standard) speed 36 kts, RA 13.000 km (7.000nm), prot. 100mm Belt, armed with 2×3 155mm/60 Type 90 Guns, 4×2 76mm/60 Type 98 DP-AA Guns, 3×2 25mm/60 Type 96 AA guns, 2×4 610mm TTs, 1 Seaplane.

Kuma Class Torpedo Cruiser Conversion proposal (1938): For the special night attack doctrine to be ported on 3 or all ships. The conversion was done on a modified design on 2 ships during the war. The original proposal had the following armament: 4×2 127mm/40 Type 89 DP-AA guns, 4×2 25mm/60 Type 96 AA guns, 11×4 610mm TTs, 5 per side, 1 centreline. Production of the Type 93 “Long Lance” remained problematic, even more for their launchers and the 127mm DP were in short supplies.

Sq. Leader Design C-39 (1938): Preliminary design for the Agano class light cruisers: Revised machinery, longer range, smaller displacement, new torpedo arrangement, two funnels.
Dimensions 162 (pp) x 173 (wl) x 174,5 (oa) x 15,2 x 5,6 meters, disp. 6.585 tons (standard) 7.800 tons (Full load), 4 shafts GST 112.000 shp 36 kts, RA 14.800 km (8.000nm).
Armour: 20mm Deck, 55/60mm Belt + extra over the Magazines/Machinery. Armed with 3×2 152mm Type 43, 2×2 76mm/60 Type 98, 2×3 25mm/60 Type 96, 2×4 610mm TTsn 18 DCS, 2 Seaplanes.

Note shown here are a modification of this design, and there three alternative designs for the oyodo class.
Interestingly, the first two in 1938 were planned four twin 127mm/40 Type 89 DP-AA Guns.

Design C-44 Agano Kai (1941): “Kai” means “improved”. This was basically a modified Agano with 4 main turrets instead of 3 and better top speed with 7 ordered in 1941 to complete the replacement of the Nagara and Sendai class cruisers. Never built, due to other priorities.
Dimensions: 175 (pp) x 184 (wl) x 16,4 x 5,9 meters for 8.250tons (standard) 9.670tons (Full load)
Prop. 4 shafts GST 153.000 shp, 38 kts, RA 11.600 km (6.300 nm)
Armour: 20mm Deck, 55/60mm Belt (Mag./Mach.) and armed with just one more 152mm Type 43 turret, 4×2 76mm/60 DP, 3×3 25mm/60 Type 96 same TTs and 2 Seaplanes
These were the last light cruisers designed in Japan.

Heavy Cruiser Design C-46 Torpedo Modification Proposal (1942): The Ibuki class, hulls 300, 301 derived from the Suzuya, it was decided to propose a massive torpedo carrier upgrade, with 5 quintuple launchers (2 either side, one centreline, no aircraft).

AA Conversions and AA cruisers projects

Design C-45 (1942) was designed as an answer to the US Atlanta and British Dido class. They were pure Anti-Aircraft cruiser from the start, like the Akizuki class flotilla leaders with four ordered for each surface battle group. Basically enlarged Akizuki type (which were very large destroyers), including seaplane facilities. They could have looked like Aganos with the same excellent 10 cm DP main guns. Src
Dimensions: 172 (wl) x 15,8 x 5,7 m, disp. 5.800 tons St. 7.150 tons FL. 4 shafts GST 103.000 shp, 34 kts, RA 13.000 km (7.000 nm)
Armour: 50mm Deck, 50mm Belt. Armed like Akizuki but with 6×3 25mm/60 Type 96 AA guns and 100 DCs, 2 Seaplanes.

Tenryu CLAA Conversion 1: 1936 plans ti rebuilt the two Tenryu class light cruisers like the British C class: 4×2 127mm/40 Type 89 DP-AA guns, 4×3 25mm/60 Type 96 AA guns, 2×3 533mm Torpedo Tubes, 36x DCs.
Tenryu CLAA Conversion 2: 1938 revision but with 4×2 76mm/60 Type 98 DP, 4×3 25mm/60 AA, 2×3 533mm TTs, 36x DCs.
Kuma CLAA Conversion proposal: 1938 same idea applied to the Kuma class. 2×2 100mm/60 Type 98, 4×3 25mm/60 Type 96 AA, 4×2 533mm TTs, 36x DCs.
Oyodo CLAA Conversion proposal (1941-42): Before the latter was reconverted as a HQ ship, but while under completion. She was to be upgraded with an impressive array of 12x twin 10cm DP guns and plethora of 25 mm (6×3 25mm/60 Type 96 AA guns), retaining two quad TT banks as well, no aviation. But this was the armament of 3 Akizuki class and industry bottlenecks cancelled the project. Known as the “Japanese Atlanta”
IJN Suzuya AA Conversion Proposal (1942): When Mogami was in repair and conversion into an aviation cruiser it was proposed to convert the next Suzuya and Kumano as Anti-aircraft heavy cruisers. Again prevented by acute 12,7cm guns shortage and no dockyard capacity. They would have carry five twin 12,7cm DP-AA mounts in place of their former main guns turrets.
IJN Kumano AA Conversion Proposal (1942): Suzuya only received half the conversion but it was planned full for IJN Kumano. The main gun rangefinder was to be replaced by an high-angle one and new Machine-gun director towers for controlled AA fire. Never carried out.

Source: Eric Lacroix – Japanese Cruisers of the Pacific War via secretprojects

Japanese “Super Cruisers”

Design X Large Cruiser (1918)

Assimilated for some authors to “Light Battlecruiser”, revolution of an earlier 1915 design, in Yuzuru Hiraga archives. Four turrets instead of three with 12-in guns but smaller hull and same displacement. Dimensions: 199,64 (wl) x 18 x 6,06 m, displacement 11.000 tons, 4 shafts GST 135.000 shp Steam Turbines 36 kts, protected by 25 mm deck and 76 mm belt. The armament comprised four single 305mm/45 (12 in) Type 37 Cannons shielded, seven single 140mm/50 Type 3 Guns and four 76mm/40 Type 3 DP-AA Guns as well as six single hull-mounted 533mm Torpedo Tubes. See deviantart design.

“Chichibu Kadekuru” hypothetical Large Cruiser class (1937)


These were designed as “heavy armored cruisers” and not yet battleships. The name is from documentation and its US authors. Probably two to four could have been planned, as found in the USN intel reports in the late 1930s. They were to be rated as 12-15.000 tons ships capable of 30knots and with six 12 inches guns. It is possible they adopted the German Deutschland class configuration to cheat on treaties. See also. It emerged from combined erroneous informations fro the Japanese side after 1936, misinformation and perhaps some False information to convince the congress to vote new warships.
Based on this hypothetical design, wargames and extrapolations pushed for the adoption of larger heavy cruisers, and this eventually led to the Alaska class design.
When the latter was known by the Japanese, this in turn led to the design the B-65 class. Thus this voluntary Japanese “fake” strongly motivated the Alaskas, which turned real and obliged both Japan to upgrade the B64 and the Soviets to start their Stalingrad class. Src Src Src

About the B64/65


The B64 was a “cruiser killer” with a moderately size artillery, and debate still rages about her nature, battlecruiser or “large cruiser” as the Alaska class. She displaced 32,000/34,800 tonnes deeply loaded, measured 787ft 5in pp/802ft 6in oa x 89ft 3in wide, had 4 single reduction geared turbines and 8 boilers for ca 160,000 shp and 33 knots, protected “only” by a belt 7.5in, bulkheads, decks 5in, and armed at fist with 3×3 12.2 in, 16x 3.9in/65 AA and 12+ 25mm AA, 8 13.2mm AA, and 2×4 24 inch torpedo tubes. Externally she looked like a less stubby, narrow-waiste Yamato.
Design was started in 1939, test carried also started with the 12.2 in gun. The design was completed in 1941 but revised as the USS Alaska construction and specs confirmed. The armament was changed to 14.2in guns and approved in 1942 but none was laid down. Aircraft carriers soon had all priority.
The upgraded B65 with her heavy artillery to answer the latter certainly was not any longer a “cruiser”. I’m just sticking to Conway’s books definition here: She was a capital ship, thus, not relevant to this topic. More on her.

Some WoW impressions:

IJN Agano


“Yodo”, a what-if design. Like Shimanto and Takahashi, fictional design using the newly planned 6-in dual purpose guns. The latter are upscaled versions of Mogami and Ibuki, but Yodo is an enlarged Atago with a 6th turret and a 18 shells broadside.

“Gokaze”

“Takahashi”

“Omono”

“Shimanto”

Grampus class submersibles (1932-36)

hms seal

Grampus class Submersibles (1936)

Royal Navy Flag Minelaying Submersibles 1932-1945:

HMS Porpoise (prototype), HMS Grampus, Narwhal, Rorqual, Cachalot, Seal

WW2 British Submersibles:
X1 | Odin | Parthian | Rainbow | Thames | Swordfish | Porpoise/Grampus | Shark | Triton | U class | T class | S class | A class

The first British internwar minelaying submersibles: The 1,800-tons Grampus-class were derived in 1936-38 from the single prototype HMS Porpoise launched 1932. Five of a modified design were built therefore after years of testing and improvements. They shared the same marine mammals names, and paid a dearly price to world war two with just one surviving: HMS Porpoise was sunk by Japanese aircraft in 1945, Grampus by Italian torpedo boats in 1940, Narwhal by the Luftwaffe near Norway Cachalot by Italian TBs in 1941, and Seal was captured in the Kattegat…

HMS Porpoise Prototype

HMS Porpoise was long-derived from a German Coastal Minelayer UC-5 obtained as war reparation, scrapped in 1923. The numerous reports helped settting a working base that was later refined in 1929.
Eventually the final designs was approved and voted for contruction in 1930, attributed to Vickers Armstrong, Barrow, laid down in 1931. HMS Porpoise was launched on 30 August 1932.
As designed she was a saddle-tank type submersible for which Vickers just enlarged their existing Parthian class. The hull shape and internal arrangement was essentially the same, but of course with a provision in th ballast to fit the torpedo wells.
The deck gun 4.7in was replaced by a 4in/40 QF Mk XII in 1934. Mines were carried in the superstructure on an endless chain, which in general layout resembling that of the converted M3, but the excessively slow diving of the latter was avoided by careful design of the mine casing. Designed diving depth was 300ft and test depth 200ft, whilst the fuel was mainly in external welded tanks. In addition to the 50 mines of conventional type, 12 M2 mines could later be carried in place of the 12 torpedoes.

⚙ HMS Porpoise specifications

Displacement 1500t standard; 1768t/2053t normal
Dimensions 289ft oa x 29ft 10in x 15ft 103in mean normal load (88.09 x 9.09 x 4.84m)
Propulsion 2-shaft Admiralty diesels plus electric motors, 3300bhp/1630shp
Speed 15.Skts/8.75kts
Range Oil 155-190t
Test Depth Circa 300 ft (90 m)
Armament 6-2lin TT (12), 1x 4.7in/45 QF Mk IX, 50 mines
Crew 59

HMS Porpoise in Service: A remarkable career

HMS Porpoise was commissioned on 11 March 1933. Her early career is in research. In 1938 she had a new commander, George Walter Gillow Simpson, RN, from 21 September to the next 15 Nov 1939.
On 25 Aug 1939 she departed Portsmouth for Gibraltar to join the 1st Submarine Flotilla, but departed for Malta the following day. On 19 Sept. 1939 she was conducting exercises with HMS Otway (Cdr. H.R. Conway) off Malta with also HMS Cachalot (Lt.Cdr. S.W.F. Bennetts). On 11 October she was scheduled to return hom, via Gibraltar (15 Oct) and made it to Portsmouth 5 days later.

On the 24th, she departed for Sheernes and Chatham Dockyard for a refit. It was completed on 18 Jan 1940 and with a new commander, P.Q. Roberts, RN she returned from the yard to to Sheerness and after trials on the 21th, she returned to Portsmouth and after exercises, including conducted mine laying exercises off Portmouth on the 25th, on 7 Feb 1940 she proceeded to Yarmouth Roads, Isle of Wight followed by exercises off Yarmouth and returned to Portmouth, alternating between the two until 12 March 1940 when she departed Portsmouth escorted by HM yacht Sona, to cover the convoy FN.20 for Rosyth.
On 16 March 1940 she arrived there, and departed three days after for her 1st war patrol, escorting convoy ON 21 to Bergen and on the way back HN 21. She was back on 25 March and departed again on 27 March for her 2nd war patrol, escorting convoy ON 23 to Bergen and HN 23 back. Nothing happened for her during the trip.
On 13 April under Cdr. P.Q. Roberts she made her 3rd war patrol, relieving HMS Clyde off Egersund, Norway.
On the 16th at 21:36 she spotted the surfaced U-3 (Type IIA U-boat) and fired from 2000 yards six torpedoes at her, 10 nautical miles south-west of Egersund, but they all missed. U-3 manoeuvered towards her and fired one torpedo, passed overhead Porpoise as she was diving. Her 3rd war patrol ended on the 29th. After a maintenance and crew’s rest, she returned for her 4th patrol after exercizes on 8 May with HMS Tetrarch in the Firth of Forth. Her patrol started on 12 May, ordered to lay a minefield off Norway.

This minefield would later claim the German minesweeper M 5. She reported on 16 april firing on an U-Boat which disappeared and later was probably U-1, which hit a mine laid by HMS Narwhal.
On 15 May 1940, under command of P.Q. Roberts, she lays minefield FD 11 (48 mines) off Kalvag, Norway. It claimed the Swedish merchant Sonja (1828 GRT, built 1923) with a german prize crew.
On 9 June 1940 she left Immingham for her 5th war patrol and laid a minefield off Smøla, Norway. On the 12th she spotted a torpedo wake but was not hit.

On the 14th she laid minefield FD 18 (50 mines) off the Ramsoyfjord, Norway. It claimed on the 18th German minesweeper M 5 (682 tons). On the 19th while charging her batteries north of Halten she was attacked by the luftwaffe, took a bomb near-hit and made a crash dive to escape. On 4th july she made her 6th war patrol, and on the 9th was attacked by aircraft underway. On the 25th, she departed Immingham for her 7th war patrol, laying a minefield off the west coast of Denmark after patrolling off Lister, Norway. This was minefield FD 23 (50 mines with flooders set for 28 August 1940). She started her 8th patrol in August, 5, nothing to report. On 13 September, 9th patrol, she laid now under command of Lt.Cdr. J.G. Hopkins, the minefield FD 26 (48 mines) in the Bay of Biscay north-west of La Rochelle, France.
On 16 Sept. 1940 at 0047 hours, she spotted and launched six torpedoes on what was believed to be a surfaced U-boat south of the Penmarch peninsula, but more likely a trawler.
On 20 Sept. 1940 she was ordered to Falmouth and Holy Loch for her Passage north through the Irish Sea. After attack exercises in the Clyde area she departed for her 9th patrol in the Bay of Biscaye, but missed the only U-Boat signalled bound for Lorient.
On 30 Nov 1940 HMS Porpoise departed Holy Loch for Halifax in Canada. She departed Halifax for her 10th war patrol, escorting convoy HX 99 on 26 December. She was back on 13 Jan 1941. On the 26th she departed Halifax for her 11th war patrol, escorting convoy HX 105 home this time. She however soon departed Holy Loch back for Canada. On 7 March while underway she made a torpedo attack on a submarine, likely German U-boat U-A which was in the area at the time, but she missed. She escorted convoy SC 26 and later SC 29. On 20 May 1941 she sailed to Troon for a refit. It ended on 1st September. Later after post-refit trials she proceeded to gunnery and torpedo exercises with HMS La Capricieuse, and was sent to Govan’s No.2 dock for preparations for her Mediterranean service.

Mediterranean Service

From late 1941 to late 1942 HMS Porpoise operated in the Mediterranean:
Under command of Lt.Cdr. E.F. Pizey, DSC, she departed Holy Loch for Gibraltar, escorted in Irish Sea by HMS White Bear and later the German B-Dienst intercepted a signal giving her exact route, but failed to spot her. On 11 October she departed Gibraltar for Malta, unloading cargo and passengers and later more to Alexandria, including personal from Malta. Axis activity on the eastern Mediterranean was so fierce this was seen as a safer way than regular warship. In november she made two more trips between Malta and Alexandria. On 28 November 1941 she was based in Alexandria, departing for her 14th war patrol, and 1st in the Mediterranean, ordered to patrol the south-west approaches to the Anti-Kithera Channel in Greece.

On 9 December a few miles south of Navarino area where she patrolled newt, in the Peloponnese, she spotted, torpedoed and badly damaged the German passenger and cargo ship Sebastiano Veniero (Jansen), carrying 2,000 UK, South African and other Commonwealth POWs from Benghazi to Taranto, 300 being killed but the rest survived as the ship was beached at Methoni. The TB Centauro was escorting her. Later the destroyers Ascari and Carabiniere arrived and the hospital ship Arno to rescue more. Despite of this, on 11 December, she surfaced and fired two torpedoes at the beached wreck but made no hit. On the 17th, while passing north of Crete for home, at 13:11 hours, she sighted a German U-boat surfaceed, but it was out of range (this was U-652 en-route to the Dardanelles and black sea).

On 2 Jan 1942 she departed Alexandria for Haifa, embarked 12 dummy mines and laid this dummy minefield off the harbour as a test then on the she embarked 46 mines in her 15th war patrol, laying them off Suda Bay, Crete. It will claim on 14 Jan the German auxiliary vessel 11 V 1 (former Greek Palaskas) and on the 18th, she torpedoed the Italian merchant Città di Livorno (2471 GRT, 1930) 15 nm NE of Cape Maleka in Crete. On 7 February she departed Alexandria for her 2nd cargo trip to Malta and a third from 3 March. Experiencing engine problems she was docked in Alexandria on 31 March (Gabbari dock) until the 9th. She departed for Port Said and back. On 18 April she started her 4th trip to Malta.
On 2 May, 20:50 she sighted an ‘U-boat’ based on a report, but she was 50 miles behind her and ciuld not attack. She was in fact the Italian Nereide.
On 23 May this tume under orders of Lt. L.W.A. Bennington, DSC, she departed Alexandria for her 5th trip.

On 7 June, she departed Malta for her 16th war patrol and escorting convoy operations to Malta as part of Operation VIGOROUS. She also patrolled off the Gulf of Taranto.
On 15 Juned, 19:35 about 140 miles west of Crete she was attacked by aviation, had ner-missed by small bombs and dived to 60 feet. At 20:25 she was attacked again, and dived too, no damage.
On 1st July she was overhauled at Port Said. On she departed Haifa for her 17th war patrol and to lay a minefield off Ras el Tin, Libya, also patrolling Cyrenaica. One mine will later claim the Italian torpedo boat Generale Antonio Cantore.

Later, a westbound convoy with Albachiara (1245 GRT, built 1904) and Sibilla (1077 GRT, built 1900) escorted by the sub-chaser Selve crossed it, but the mines had not time to be armed. She tried to torpedo Sibilla but missed. However she later sank the Italian transport Ogaden (4553 GRT, built 1905) off Ras el Tin. She was transporting 200 POWs from Benghazi to Tobruk, escorted by Generale Carlo Montanari (another “Generali” vintage WW1 destroyer). MAS 561 came to pick up survivors but was soon chasing Porpoise.

On 15 August, she spotted, torpedoed and sank the Italian merchant Lerici (6070 GRT, built 1941), 120 nm north of Ras Amir while in convoy with Ravello (6142 GRT, built 1941) and escorted by the destroyer Nicoloso Da Recco and TBs Polluce, Calliope and Castore. Hit by two torpedoes she was abandoned. Polluce made three runs with 38 depth charges, claimed Porpoise sunk and returned to pick a survivor. Bersagliere and Mitragliere finished off the wreck by gunfire and rescued more survivors, but twenty-one were missing. on the 19th however she was off Tobruk detected and depth charged by the TB Lince escorting the transport Iseo (2366 GRT, built 1918) to Benghazi. She claim having damaged her, which was true. She stayed under until not hearing anything and surfaced to depart for home, escorting on her way on 20 August by Beaufighters in escort and later two Hunt-class destroyers. While she was in repairs in Port Said, one of her mines claimed Generale Antonio Cantore off Tobruk.
She departed Haifa for her 18th war patrol on 28 September, laying a minefield off Tobruk and proceed to Malta to unload cargo aboard. Once done on 10 October she was ordered to the Ionian Sea, with just four torpedoes aboard. On the 13th afternoon, she was informed of a convoy of two merchant ships proceeding from Brindisi to Benghazi but she missed the convoy which passed a little further east. She proceeded to Beirut next, and on the 29th departed to unload cargo to Malta. On 18 November she spotted an unidentified U-Boat about 3 miles away which was Pietro Micca on a transport mission to Tripoli. In fact the latter also spot her ahd stayed distant as ordered. The following day Porpoise spotted and fired a torpedo at the auxiliary patrol vessel F39/Fertilia off the Libyan coast but missed. However later that day she torpedoed and sank the Italian tanker Giulio Giordani (10,534 GRT, 1939) 45 nm NE of Misurata, Libya (she had been torpedoed and damaged earlier by British aircraft, abandoned). On the 21th she was ordered to return to Malta via Kerkenah and two days later, spotted, torpedoed and sank thesame Italian auxiliary patrol vessel F39/Fertilia she previously missed. On 4 December she left Malta for Gibraltar.

Pacific Service

On 14 Dec 1943 HMS Porpoise departed Gibraltar for Portsmouth. She conducted exercises off Portsmouth and transited to the Holy Loch. In February 1944 she trained in the Clyde area and alternated with Campbeltown. They went on until 17 Apr 1944, when she departed with Lt.Cdr. H.A.L. Marsham as new commander Holy Loch for Gibraltar. She was ordered for the Far East, assigned to the 4th Submarine Flotilla based at Trincomalee. She was escorted in the Irish Sea by HMS Telemachus and HMS Flint Castle. On 6 May she departed Gibraltar with HMS Telemachus and HMS Clyde for Malta, escorting underway convoy KMS 49. From there, she transited to Alexandria, Suez, Aden and on in June, Trincomanlee.
The Malacca Minefield
On 1st Jul 1944, she departed Trincomalee for her 20th war patrol and 1st in the Far East, ordered to lay mines in the Malacca Strait. She laid 30 mines (minefield ML 014) off the mouth of the Deli River, Sumatra, Netherlands East Indies. Her mines would claim Cha-8 (100 tons), the freighter Bukun Maru and Special Minelayer No.1 in March 1945.

Operation Rimau (attack on Singapore)
On 27 Jul 1944 she departed Trincomalee for Fremantle in Australia assigned to the 8th Submarine Flotilla. On the 11th she departed Fremantle for her 21th war patrol to conduct Special Operation Rimau, launching fifteen one-man submersible canoes (‘Sleeping Beauties’) against the naval base of Singapore. In all, she carried 96 passengers and crew members. The canoe were presumably carried inside the mine wells. 17/18 saw her passing Lombok Strait and on the 23th close to midnight she launched a folbot manned by Lt.Cdr. Donald Davidson, RNVR, and Corporal Clair Stewart in reconniasance of the island of Merapas usable as an advance base. The following day they were back confirming it was emtpy and safe as base. On the 28th, 13:59 HMS Porpoise captured the Malay junk “Mustika” later used for the operation, sneaking in with canoes aboard. The Malay crew was kept hostage in the submarine as the boarding party and the junk was in tow. On 29-30 September she transferred the Canoes to the Mustika and sailed away. This was a suicide mission as none of the 23 men which entered the harbor, apart three ships rumoured sunk they were all killed or executed by the Japanese.

The loss
Not waiting for the special operatives, she departed on 4 October for Lombok and returned to Fremantle. On the 30 she was sent back to Colombo, and later Trincomalee. She proceeded to various exercizes and on 2 December
under command of A/Lt.Cdr. H.B. Turner, departed Trincomalee for her 22th war patrol and to lay a minefield off Penang as well as patrolling the Nicobar Islands. The minefield ML 019 had 46 mines in two rows but claimed no victim. She ended her patrol and spent the rest of the year in Trincomanlee.

On 3 Jan 1945 she departed Trincomalee for her 23th war patrol, ordered to lay another minefield off Penang. Once done, she departed for a patrol while at 13 January, 01:01 hours, HMS Stygian received Captain S.4’s signal about the submarine being in trouble 17 miles northwest of Pulo Perak, via an Ultra decrypt. It established that on 11 January she had been attacked by a Nakajima B6N2 Tenzan heavy bomber from 331 Air Group based at Penang. One of the two closest 60kg bombs missed her port bow but the other was a direct hit. Unable to dive she was attacked again by another Tenzan at 11:45 off Perak Island while she managed to submerged but was leaking oil as reported by the Japanese. At 20:57 hours she had a third attack with six 60kg bombs falling and again at 10:00 hours the following morning. IJN aviators just had to follow the leaking oil tray.
HMS Stygian arrived and tried to contact Porpoise by radio, searched the area but found nothing. She sank at an unknown location with all hands: Her wreck had never been discovered yet. As sad end for probably one of the most succesful allied submarine of world war two.
Nevertheless, her minefield claimed on 15 January the Japanese auxiliary minesweeper Kyo Maru No.1, on 27 March the Japanese auxiliary minelayer Ma 1 and on 18 May the Japanese submarine chaser Ch 57.

The Grampus class

Usually assimilated with the Porpoise, but of a later, improved design, these five boats approached the double-hull type, with a pressure hull shaped to include the principal tuel tanks. They were laid down in 1933-36 and completed in 1936-39, while P411-P413, which would have differed io having a circular section pressure hull, ordered from Scotts on 13 January 1941 but cancelled in September. Stability was increased from that of Porpoise, as was the reserve of buoyancy, and armament was the same apart from the later addition of a 20mm gun in HMS Rorqual. Diving depth figures remained the same but fuel capacity was reduced. Grampus and Cachalot were sunk by Italian Torpedo Boats, Narwhal presumably by the Luftwaffe, Seal damaged by a mine before capture and integration in the Kriegsmarine (see later).


Author’s old illustration

⚙ Grampus specifications

Displacement 1520 standard; 1810t/2157t normal
Dimensions 293ft oa x 25ft 6in x 16ft 10in mean normal load (89.30 x 7.77 x 5.13m)
Propulsion 2-shaft Admiralty diesels plus electric motors, 3300bhp/1630shp
Speed 15.75kts/8.75kts.
Range Oil 119-147
Test Depth (tested, not max) Same as Porpoise
Armament Same
Crew Same

General assessment

As seen above, these were the only and last minelayers submarines deployed by the RN in WW2, and they were globally successful. Their large size guaranteed long range, and they were roomy enough to be used as cargos and carry special operations with teams and their equipments. HMS Porpoise was by far the most successful, perhaps of all British submarines of the war. The top ten (yet to document and create) often includes HMS Splendid (P228, 9 kills), HMS Upholder (U-class) sinking four Italian warships, and HMS Trident operating from a Soviet base which sank the Ostpreufen, Donau II, Bahia Laura, UJ-1213, damaged Levante (4769 GRT) and sunk UJ-1201. Both captains, Geoffrey Mainwaring Sladen and Malcolm david Wanklyn became “aces”, which was rare. The captain turnover was such that not many could stay in place. Also the practice of “aces” in submarines was more sketchy, and not well established in the RN. Was there a difference between trade ships and warships ?
Nevertheless, while combining three main theaters of operations from 1939 to 1945, and with the capacity of laying mines in addition to their torpedo and deck gun, the class had the potential to have the best kill/tonnage ratio.
HMS Porpoise based on this was certainly in that top ten, but her sad end was caused by her leaky fuel tanks, an issue detected and solved by the following Grampus class. She indeed combined direct hits with indirect ones through her minefields.
The Grampus class were less successful (see later).

Read More

Books

Akermann, Paul (2002). Encyclopaedia of British Submarines 1901–1955 (reprint of the 1989 ed.). Penzance, Cornwall: Periscope Publishing. ISBN 1-904381-05-7.
Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
Colledge, J. J.; Warlow, Ben (2006) [1969]. Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
Chesneau, Roger, ed. (1980). Conway’s All the World’s Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7.
McCartney, Innes (2006). British Submarines 1939–1945. New Vanguard. Vol. 129. Oxford, UK: Osprey. ISBN 1-84603-007-2.
Caruana, Joseph (2012). “Emergency Victualling of Malta During WWII”. Warship International. LXIX (4): 357–364. ISSN 0043-0374.
Colledge, J. J.; Warlow, Ben (2006) [1969]. Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
Frampton, Viktor & Domenico, Francesco de (2015). “Question 13/51: British Submarine Actions of WW II”. Warship International. LII (2): 116–118. ISSN 0043-0374.
Napier, Christopher (2017). HMS Rorqual: Commanded by Lennox Napier DSO DSC: June 1941–December 1943. Friends of the Royal Navy Submarine Museum.

Links

https://en.wikipedia.org/wiki/Grampus-class_submarine
https://en.wikipedia.org/wiki/HMS_Porpoise_(N14)
https://uboat.net/allies/warships/ship/3415.html
https://www.aidmen.it/forums/topic/250-sommergibile-hms-rorqual/
https://uboat.net/allies/warships/ship/3416.html
No model kit found yet.

3D

The Porpoise/Grampus class in action:

Royal Navy ww2 HMS Grampus

grampus
HMS Grampus (N56) was the lead ship of her class of mine-laying submarine of the Royal Navy. She was built at Chatham Dockyard and launched on 25 February 1936. She served in World War II off China before moving to the Mediterranean Sea. She was sunk with all hands by the Regia Marina on 16 June 1940.
On 16 June 1940, under the command of Lieutenant Commander C. A. Rowe, Grampus laid mines in the Syracuse and Augusta, Sicily area. She was seen by the Italian torpedo boat Circe, which was on anti-submarine patrol with Clio, Calliope, and Polluce. Within a very short time, Grampus was destroyed. Wreckage came to the surface along with air bubbles and oil. Polluce was credited with the kill. There were no survivors. Some sources give the date of this action as 24 June 1940. See the details on uboat.net

Royal Navy ww2 HMS Narwhal


HMS Narwhal short but well filled wartime career. In 1939 she spent her time conducting exercises off Portland. On 15 Nov 1939 under command of Lt.Cdr. E.R.J. Oddie, she departed Portsmouth for her 1st war patrol, ordered to proceed to Halifax while escorting convoy OA 36 in part. On 2 Dec 1939 she departed Halifax with her sister HMS Seal, proceeding back home while escorting convoy HXF 11.
On 14 Jan 1940 she conducted exercises in the Firth of Forth and soon after departed to escort a Convoy to Norway, Bergen, which was formed to carry back steel as HN8 on the 20th.
In February 1940 she escorted the largest convoy yet with 29 ships escorted by five destroyers and her. She escorted back from Bergen the back Convoy HN 10 and later the Convoy ON 11 to Bergen. Next were the convoys ON 12 and and ON 14. With HN 14, on 25 Feb 1940, she helped HMS Imogen and HMS Inglefield to sink U-63, south east of the Shetland Islands. After ON 17 she was back in exercizes in March, at Scapa Flow, notably direction finding trials.
On 13 Mar 1940 under command of Lt.Cdr. R.J. Burch, she was sent to Rosyth and assigned to operation R.3 (assistance to Finland by the occupation of Norwegian key points), her 7th war patrol. But this was curtailed by the Finnish armistice, the subs were recalled on 16 March. Bu she was bombed and had to dive escaping a Do 17 aircraft on the 17th.
In 1-5 April 1940 she departed Blyth for Immingham, embarking 50 mines as her 8th war patrol, laying a minefield in the Heligoland Bight (F.D.1).
On 10-17th for her 9th war patrol she laied minefield (F.D.5) off Skagen. It will claimed the German auxiliary minesweepers M 1302/Schwaben, M 1102/H.A.W. Möllerthe, Gnom 7, Kobold 1 and Kobold 3, the German minesweeper M 11, German auxiliary submarine chaser UJ D/Treff VIII, the armed trawler V 1109/Antares and Swedish merchant Haga.
On 1st May after laying the minefield F.D.6 (50 mines) in the Kattegat she attacked a German convoy, torpedoed/sank the troop transport Buenos Aires (6097 GRT, 1912) and torpedoed, damaged (constructive loss) the troopship Bahia Castillo.
Ships damaged by mines laid by Narwhal also included the armed trawler V 403/Deutschland, and the German merchant Togo (later converted as a fire direction ship) on May, 20, and Clara M. Russ. The auxiliary minesweeper M 1101/Fock, Hubert and merchant Palime were also damaged, beached but total losses. They were sunk by later minefields at Feistein Island/Bud, Jaerens, also in Norway (south of Stavanger) in June, Haugesund and kristiansund.
Narwhal may also have sunk U-1 noted in the Kriegsmarine as disappeared on patrol, on 6 April 1940, it is likely she ran into a minefield from Narwhal although Porpoise reported firing upon an unknown submarine, which may be her.

Sinking
HMS Narwhal left Blyth on 22 July 1940 in what was her last war patrol. On the afternoon of 23 July, an aircraft reported attacking a submarine in her presumed area, believed by the Germans to be HMS Porpoise and assumed sank. Nevertheless, no new camed from Narwhal. She was presumed lost by unknown causes. In 2017, a Polish expedition in search of ORP Orzel found an unknown wreck, identified to be most likely HMS Narwhal, based on sonar data. On most publications she is reported “sunk, 30 July”.
See the details on uboat.net

Royal Navy ww2 HMS Rorqual

hms rorqual

Far East Campaign

HMS Rorqual was Commissioned on 10 Feb 1937. She conducted her sea trials, and post-fixes in a dockyard before being assigned t the 4th sub squadron in the far east. Nothing is known about her early months in fall 1937 up to late 1939 (nearly two years), probably aletrnating between her Shanghai and Hong Kong station, ports visits and exercizes. On 6 September 1939 under command of Lt.Cdr R.H. Dewhurst, she conducted exercises off Singapore notably with HMS Grampus and on the 13th she departed for her 1st war patrol off Sabang. On 14 October she made her second in the Sunda Strait followed by exercises off Singapore in November. On the 7th, she was again patrolling off Sabang, until the 26th. On 5 December, she was in exercises with HMS Tenedos followed by a refit on the 20th, leaving on 13 April 1940 Singapore Navy Yard. After trials and fixes she departed on the 28 April forr Colombo and proceeded on orderes to the Mediterranean via Aden, Port Said and her first hole port of Alexandria (16 May) before departing for Malta.

Mediterranean Campaign

On 27 May 1940 HMS Rorqual laid a practice minefield off Malat, and was soon ready for her first wartime patrols in the Med. She multipled operations of minelaying, claiming the Italian merchant vessels Loasso, Celio, Leopardi, and Salpi, the water tankers Verde and Ticino and pilot vessel F 34/Rina Croce. But her more covered kills were the Italian torpedo boats Calipso, Fratelli Cairoli, Generale Antonio Chinotto, Altair and Aldebaran as the Italian auxiliary submarine chaser AS 99 Zuri and German troop transport Ankara. They also sank the former French merchant P.L.M. 24 and armed fishing vessel Coligny. By mines laid she also claimed damaged the Italian merchants Caffaro, Ischia and Carbonello A.

With her own torpedoes, Rorqual sank the Italian tanker Laura Corrado, submarine Pier Capponi, merchants Cilicia and Monstella, German tanker Wilhemsburg, ex-French merchant Nantaise. She also badly damaged the Italian auxiliary cruiser Piero Foscarin but missed and Italian submarine and the merchant Securitas. By Gunfire she sank two Greek sailing vessels, presubamy used by the Germans. By August 1940 she attacked an Italian convoy but missed with her spread the merchants Verace and Doris Ursino. She was chased off and depth charged by the Generale Achille Papa, but escaped.

In January 1941, HLS Rorqual attacked the tug Ursus and a floating battery dealt with with her single 4-inch gun surfaced at about 500 yards. The tug put up a firce response so Rorqual shifted fire to silenced her, before finishing off Ursus, until her fire became dadly accurate, forcing the submersible to dive. The only torpedo she fired had a gyro malfunction, returning straight at her ! She had to dive deeper to avoid it. But Ursus sank anyway as the battery, on fire, was evacuated but later towed to Dubrovnik.

Rorqual like her other sister ships was operfectly apt at carrying stores in her mine wells. On 19 January 1941 in fact she demonstrated this capability first: She loaded her cargo in Alexandria, and was the first doing this cargo trip to Malta. In all she would made five such runs to Malta in 1941. Later that year by June 1941 she fell under command of Lt. Lennox William Napier. She made more missions but with nothing notable, and a refit and more runs from Alexandria and in 1942 from Beirut, the British “magic carpet runs”. They notably carried avgas drum tanks (well suited for her mine wells) for the local Hurricane fighters and kerosene for cooking. Passengers were also carried in both ways. By October 1943 she carried from Beirut to Leros an entire battery of 40mm Bofors guns and their towing jeep to boot. The isolated island was indeed attack by the German air force.

Operations for 1943-44:
On 21 Nov 1943 after departing Beirut for hr last trip to Malta she was ordered to return to the U.K. for a refit and on 2 December under command now of Lt. G.S.C. Clarabut she transited at Gibraltar and escorted the convoy GUS-23 back home. Clarabut took command as Lt. Cdr. Napier was ill with jaundice and just now a passenger. On 11 December as she sailed, a German U-boat was reported in the Straits and this delayed her trip to the following day. On the 19th she met off Bishops Rock HMS Patti escorting her surfaced to Falmouth later in the evening.
On 20 December, she departed Falmouth for Portland escorted by Vichy French submarine chaser Chasseur 5. The following day she arrived in Portsmouth when Chasseur 5 suddenly capsized with 22 aboard and she picked up three survivors. While off Portsmouth she met the destroyer Blyskawica and started her refit at the Portsmouth Dockyard from 28 December to 6 August 1944.
Based in Yarmouth and proceding to the Holy Loch escorted by HMS Cutty Sark she started trials and training, notably in the Clyde area and at the torpedo firing range of Arrochar, noise trials at Loch Goil., mine detection) trials off Fairlie and attack exercises, radar drills off Campbeltown, D/G tials off Helensburgh and log calibration, engine trials in Loch Long.on 19 October she was docked in AFD 20, Holy Loch and 4 days later departed again for Gibraltar intended for the Far East. From March 1944 she was under command of Lt. John Philip Holroyde Oakley, DSC, RN.
She escorted underway convoy KMS-67 and arrived on 2 Nov 1944 to Gibraltar, proceeding to Malta, Port Said, Aden, Trincomalee in December arriving on the 14th.

Return to the Far East

HMS Rorqual started operations against the Japanese as part of the British Pacific Fleet (BPF), laying minefields which claimed three Japanese sailing craft, also blasting three coasters with gunfire, damaging a fourth one. This was all in the east Indies. For example on 22 January she laid 50 mines (minefield ML 026) in Nancowry Strait, NE of Port Blair, Andaman Islands.
Later this month she is ordered to conduct air/sea rescue duties in the Andaman Sea. On 18 March she departed Trincomanlee for her 32th war patrol off the West coast of Sumatra and conducting the special operations Meridian and Caprice. Notably on 2 April 1945 she sank two sailing vessels with demolition charges off the west coast of Sumatra. She sailed to Fremantle and on 30 April departed Fremantle for her 33th war patrol, laying a minefield of Batavia (10 May).
On 20 May she was back at Fremantle and on 3 June departed for home, the only surviving ship of the Grampus class. He trip via Trincomalee, Port Said, Gibraltar, Portsmouth was followed on 28 July by her placement in reserve, under nominal command of John Philip Holroyde Oakley up to that date. She was later sold off, BU off Cashmore, Newport from 17 March 1946.
More details on Uboat.net

Royal Navy ww2 HMS Cachalot

Hms_cachalot_n83_submarine
Cachalot entered service under command of Lt.Cdr. Sydney William Floyd Bennetts from 26 Aug 1937 (he stays her captain until 15 Jun 1940). In 1937-39 she was presumably in British waters (no logs). On 1st September 1939 she departed Britain for Malta. She conducted exercizes with notably HMS Porpoise and Otway, and later Sealion and Oswald. In October she returned home via Gibraltar.
On 29 Oct she departed Portsmouth for her 1st war patrol in the North Sea. He second patrol started on 11 November, escorting a convoy to Halifax, Canada. She trained there in Demeber with HMS Hunter and HMCS Restigouche. She escorted a large convoy back home from 29 December 1939 to 12 January 1940.

She had later a refit at Chatham Dockyard, and exercizes off Portsmouth in April. On 13 April she departed Blyth for Immingham to embark mines but collided at 21:25 off Whitby (rammed by accident) by the Italian merchant Beppe. She was sent for repairs to the Tyne, Devonport Dockyard and Sheerness. On 15 August now under command of Lt.Cdr. J.D. Luce, departed Rothesay for her 4th war patrol, 1st time in the Bay of Biscay, and she had to lay a minefield off the Gironde estuary. She torpedoed and sank German submarine U-51 on the 20th in the Bay of Biscay.
Her minefield would later claim in September the German auxiliary minesweeper M1604. On the 24th she spotted and attacked a submarine with torpedoes in the Bay of Biscay, which was almost certainly U-48 (KL Heinrich Bleichrodt), but missed.

She served from the Holy Loch in December. For her 7th war patrol she was sent off Punta Delgada in the Azores, as a German invasion of the Azores was feared at the time.
On 26 Jan 1941 she laid minefield FD 28 (50 mines) off Bud, Norway. On 5 February she departed Holy Loch for her 9th war patrol, and to lay a minefield off Norway, which happened to be signalled later as Vest Fjord (which claimled the Norwegian merchant Huldra). On 28 March, now under command of Lt. H.R.B. Newton, DSC, RN, she laid minefield FD 32 (50 mines) off the Gironde estuary. By late April she was ordered to Plymouth and from there to Gibraltar to commence Mediterranean operations.

She transited via Malta to Alexandria and Port Said and started a serie of storage trips to the beleaguered Malta. Cachalot left Malta on 26 July bound for Alexandria when at 2:00 on 30 July she was spotted by the Italian destroyer Generale Achille Papa, and she had to crash dive. When resurfacing she was attacked by her. While attempting to dive again her upper hatch jammed, and she was rammed. The crew had to scuttle and abandon her. Apart the Maltese steward all were picked up by the Italians. See the details on uboat.net

Royal Navy ww2 HMS Seal


After her commission, HMS Seal performed her sea trials at Dartmouth-Torbay and made a first successful deep dive on 1st June 1939 when leaning of the loss of HMS Thetis that same day. Many of the crew had friends in this boat. She perform her torpedo trials at Gosport.
On 4 August 1939, she sailed to the far east squadron (in Shanghai), joining HMS Grampus and Rorqual via Gibraltar, Malta and Suez, but as the war broke out she stayed at Aden. She immediatelt started a round of patrols watching Italian activity in the area, fearing some help to German submarines. Back home, she escorted a damaged destroyer in the Mediterranean before reaching the North Sea for her first war patrol near the Dogger Bank, attacked by the Luftwaffe. Her second patrol show her escorting a convoy escort to Halifax in a 14-day crossing. Next she was assigned to Elfin, Blyth, in Northumberland. She made more war patrols in the North Sea, as part of the Norwegian campaign, after relocation to Rosyth.

Norway Operations
By February 1940, HMS Seal received commandos aboard (a boarding party) intended for the German tanker Altmark (which resupplied Graf Spee and was last spotted in a Norwegian fjord -still neutral). But the show was stolen by HMS Cossak but Seal was later visited by an admirative Admiral Horton in Rosyth for the general state of the boat and crew. In April 1940 the invasion of Norway had the submersible ordered even close to the Norwegian coast. Captain Lonsdale decided to enter Stavanger fjord, to reach Stavanger harbour, guided by his new precision Asdic to avoid being grounded along the narrow way.
Once arrived, he spotted four merchant ships under neutral flags, requesting to attack, having the personal to launch a strike on a seaplane base and land a shore party to sabotage the railway. But this was refused by Horton to not create another displomatic incident after the capture of the Altmark. There was also a shallow-draft German naval craft which he declined to hit by torpedoes, so the disappointed crew had to make the dangerous trip back through the fjord and proceed to Rosyth. HMS Seal narrowly escaped a torpedo attack underway and also later rammed and scrapped by a merchant vessel.

Dry-docked at Chatham, HMS Seal as HMS Cachalot were repaired, completed at Blyth and she replaced Cachalot for minelaying missions, notably Operation DF 7, a dangerous minelaying in the Kattegat, preventing the kriegsmarine to pass through Denmark and Sweden. Captain Bethall at the head of the flotilla, failed to persuade Admiral Horton to send her due to the numerous hazards of the place and narrow shoals, making the large subersible rather cumbersome in these waters. This was partly due to the exploit of Seal, navigating with Asdic through Stavanger fjord.

The Suicide Skagerrak minelaying Mission
On 29 April 1940, Seal left Immingham with 50 mines and entered the Skagerrak, meeting HMS Narwhal leaving, having just scoring six hits with six torpedoes, a rare feat of markmanship. This no doubt pimped up the crew’s resolve. Seal was maintained at shallow depth, maintaining speed lopw to spare fuel. But at this low depht she was spotted by a German Heinkel He 115 on 4 May, at about 02:30. She had to dive to the bottom, circa 90 feet (27 m) after being slightly damaged by a bomb. Lonsdale later detected German anti-submarine trawlers looking for them as he reached his initial minefield area, and diverted to the secondary target area. Her started to lay down these at 09:00, completing it 45 minutes later.

Mission accomplished, Londsdale ordered to turnback and head for home, with the trawlers still overhead. He tried an evasive course using Asdic to detect the pauses made by the trawlers to listen. At 3:00 pm, he spotted nine MTBs heading from a different direction but is was still daylight, and the Kattegat was still too shallow, but he evaded detection by zig-zaging. At 18:00 hiowever as he started to surface after such a long underwater crossing, he unwillingly entered an uncharted minefield. His two hydroplanes caught a mine stay-cable. At 06:30 pm the attached mine attached itself ot his stern, and scraped until one of the detonators hit, trigerring the mine’s explosion: HMS Seal was severely damaged and started to flood in.

The crew’s miraculous escape
All watertight doors were quickly sealed, and miraculously all but two of the crew were still alive. Even those, trapped in the after end, later managed to make their way to the control room. The German ship apparently assumed her sunk or never heard the explosion and left the area. Emergency repairs were done and at 22:30 Londsdale ordered to surface at last.
At 10:30 pm as the boat was emerging her stern stayed stuck on the sea bed until the bow made sharp angle which made work inside impossible. Even air quality deteriorated much, and attempt was made to blow air into the rear trimming system and for the second attemptn the 11-ton drop keel was released. After using even more compressed air to blow the remaining tanks, this was still unsuccessful. The third attempt also failed while oxygen ran out.

At 01:10, Lonsdale called to prayer with his crew moving as far forward as they could to rebalance, many fainting in the process. The captainalso thought to use the Davis escape gear but it needed hours to escape while flooding was a risk. Engineers managed to open a salvage-blow for a 4th and final attempt which saw the diesels, pushed to the absolute limit, catching fire, soon dyring out due to the lack of oxygen. Batteries were also nearly empty while high pressure air was not exhausted. While all seemed lost for good, one engineer realised there was still one air pressure group left, reached and opened the valve, and all that were still aware at the time felt the boat raising again, and this time, the stern followed.

Seal eventually surfaced at 01:30 and immediately with their last strenght men present managed to open the hatch. Fresh air usehed inside, causing blinding headaches as the crew had been so deprive from oxygen for so long. But all ultimately survived. Lonsdale arrived on the bridge and started to scan the horizin, sighting land. He decided to make it for neutral Swedish waters. Confidential papers were thrown overboard as the cipher books, Asdics were destroyed and also thrown overboard. He sent a message to the Admiralty “Am making for the Swedish coast”. He would receive “Understood and agreed with. Best of luck”, “Safety of personnel would be your first consideration after destruction of the Asdics”. However after some well-needed rest and restoration, engineers started to reports the rudder was damaged beyond repair. Still the boat could go in reverse but the only working engine was barely in shape and soon died out, leaving the boat stranded.

At 02:30, Seal unfortunately, now surfaced and unable to dive or move again, was spotted and attacked by two German Arado Ar 196s and a Heinkel. Lonsdale stayed the bridge under fire using a Lewis gun, which jammed, then another, which jammed too. Considering all his option, Londsdale decided to surrender. He had the white messroom table-cloth quickly hoisted on the mast. Leutnant Schmidt of one of the Ar 196 landed alongside and asked in english the captain to swim to him for a parley. Lonsdale, aged 35, made it so, and shortly after the enterview, the chief petty officer swam to the other Arado that also landed. The crew waited as the armed trawler UJ-128 arrived at 06:30. The crew attemped to scuttle their boat, but failed as a German boarding party took the crew in custody. Although leaking and patrly flooded, the crew saw in horror their submarine being towed to Frederikshavn.

Under the svatiska: The short career of “UB”
They would learn after the war that their mine belt sank the German freighter Vogesen (4241 BRT) and three Swedish ships until 5 June. But their story ends there. They became POWs until the end of the war. As for their submarine, it was the only British sub in this war to be captured and reused by the Kriegsmarine. It was no long to realize its potential as a minelayer indeed, as there were none (yet) in the Kriegsmarine. She was simply named “UB”.
She had temporary repairs at Frederikshavn, then was towed to Kiel and was completely refurbished under supervision of Admiral Rolf Carls which saw her usefulness. Her insisted to have her operational at any cost. This was long, complicated and went on until the spring of 1941. UB made her sea trials and first dive under command of Fregattenkapitän Bruno Mahn, aged 52, a trusted veteran and oldest German submarine commander in this war.

The boat was naturally showcased propaganda exhibit and acted as training boat until by late 1942 Krupp was able to deliver the brand new tailored minelaying mechanical system. The boat made minelaying runs which revealed so many issues left to solve, with cost soaring sky high. Dönitz ultimately pull the plug. In mid-1943 he decided to retire her for good (the dedicated Type XB – A dedicated post on them is in writing). She was paid off, stripped and left in Kiel dockyard but later hit and sunk as Admiral Hipper. For all what she costed, the only gain retired from this all was the British contact pistol torpedo detonator judged of superior design and subsequentely adopted.
On 3 May 1945 UB was scuttled in Heikendorf Bay and her wreck demolished by explosives.

Fate of the crew:
The crew was interrogated by the Kriegsmarine (meaning in a fair way, not Gestapo methods). Officers and ratings were separated and sent to several POW camps until April 1945. The crew had been adopted by the village of Seal which sent considerable gift packages to the crew until then. Two managed to escape, Petty Officer Barnes in poland which later made contact with the Polish underground. They reached the Soviet border, but the latter shot Barnes dead while his companion Briggs was emprisoned into Butyrka prison in Moscow. Engineer Don “Tubby” Lister also managed to escape many times until confined in the Oflag IV-C, Colditz Castle, built on a rocky hilltop. Relocated by a ruse in an open camp, he escaped in late 1942 to Switzerland and later arrived home at last. The rest of the crew was mostly detained in Marine-lager Westertimke, well treated. By April 1945, the Allies were at Bremen, 15 nautical miles (28 km) away, and they were marched off to Lübeck. During the journey, the column came under attack from Allied Spitfires. For surrendering his boat Both Londsdale and Lt. Trevor Beet faced court-martial in 1946, but given testimonies and report of his conduct in the circumstances, he was honourably acquitted. Personal note here: This story is too good not to be made into a movie.

Casablanca class escort carriers (1942)

main picture casablanca

Casablanca class

US Navy 50 Escort Aircraft Carriers (1942-44): USS Casablanca, Liscombe Bay, Coral Sea, Corregidor, Mission Bay, Guadalcanal, Manila Bay, Natoma Bay, St. Lo, Tripoli, Wake Island, White Plains, Solomons, Kalinin Bay, Kassan Bay, Fanshaw Bay, Kitkun Bay, Tulagi, Gambier Bay, Nehenta Bay, Hoggatt Bay, Kadashan Bay, Marcus Island, Savo Island, Ommaney Bay, Petrof Bay, Rudyard Bay, Saginaw Bay, Sargent Bay, Shamrock Bay, Shipley Bay, Sitkoh Bay, Steamer Bay, Cape Esperance, Takanis Bay, Thetis Bay, Makassar Strait, Wyndham Bay, Makin Island, Lunga Point, Bismarck Sea, Salamaua, Hollandia, Kwajalein, Admiralty Islands, Bougainville, Matanikau, Attu, Roi, Munda.

The world’s largest carrier program


In late 1942, the USN urgently needed more aircraft carriers to face its obligations both in the Atlantic and Pacific. Conversion of existing C3 cargo hulls took time despite their seemingly easy and limited nature, and there was some desperation on how to increase the output.

In the early summer of 1942, Vancouver shipyard’s owner Henry J. Kaiser, already famous for the amazing output to deliver Liberty ships suggested the American government to manage the mass construction of a batch of 100 per year. His mass-construction simplification process and technology of continuous assembly and modular approach was, as he argued, adaptable to warships.


USS Guadalcanal(CVE-60) in 1944

President Roosevelt has become interested in the project, since in mid-1942, fleet carriers in construction were still far from ready and the need was urgent anyway. He confered with the yard’s team, Kaiser eventually being granted an offer to finance the construction of 50 aircraft carriers at once.
The Bogue class having been extensively tested successfully, it was proved that such vessels could provide air cover for the Pacific landing squadrons while continuing to serve in the Atlantic. Rather than scatter other series between several models of converted freighters, Henry J. Kaiser, the wealthiest holder of the largest and most prolific shipbuilding yards in Vancouver, Canada, proposed to the Admiralty to produce 100 escort carriers in record time (less than a year), based on his method of building Liberty Ships.

The Casablanca became the most prolific class of aircraft carriers in history. Although narrower and crampier than the Bogue class, their larger holds made it possible for them to carry more planes and fuel. They were also much faster thanks to their turbines, coming from fast cargo ships designed to escape U-Bootes. They were actually built in record time, the first, the USS Casablanca, laid down in November 1942 and into active service by July 1943 whereas the last one, the USS Shamrock Bay, was laid down in November 1943 and active in March 1944 (So in just in 5 months !).

They were ready in time for the great pacific operations, and 5 would be sunk in combat, USS Liscome Bay in November 1943, Gambier Bay and St Lô the same day during the battle of Leyte – victim of the Japanese guns. Kamikazes would also claim the USS Ommaney Bay in January and the USS Bismarck Sea in February 1945. After the war, some served for a time as ASW support and carriers thanks to their onboard helicopters. Most were broken up in 1960. They were a pure product of wartime and never intended to last long.

Genesis of the need, specifications and design

In WWI already, UK experimented in converting light cruisers to airplane carriers, as HMS Cavendish and depite the project was cancelled, it became subject of interest in the earlu interwar, more promising in some ways that the ponderous battleships conversiosn for fleet use. In 1925 already, the USN General Board considered the conversion of cruiser hulls to aircraft carriers. Treaty limitations still allowed for uncommitted construction tonnage to enable more carriers than authorized, using the treaty loophole of less than 10,000 tons ships. The IJN also took that alley, resulting in the Ryujo. About this uncommitted tonnage for small carriers, the board eventually reported:

“Incomplete studies of the subject by the Bureau of Construction and Repair and the meagre information available concerning the performance of airplanes from carriers of approximately 10,000 tons displacement does not justify building them at this time.”

“light” carriers resurfaced by May 1927 when LCdr. Bruce G.Leighton analyzed the problem in “Light Aircraft Carriers, A Study of their Possible Uses in So-Called ‘Cruiser Operations,’ Comparison with Light Cruisers as Fleet Units.” He already distinguished between CVL’s and CVE’s roles, between capital ships attack, fleet support and ASW patrols and reconnaissance. He considered them “worthy substitute for the light cruiser, or even preferable”.
In March 1939, Capt. John S. McCain, Sr. onboard USS Ranger (which experimented precisely the viability of such intermediate-light designs), wrote to the Secretary of the Navy about the ututility of eight “pocket-size” fast carriers (which Ranger was not) in orer to supplement fleet CVs rarther than replacing them.
Rear Admiral Ernest J. King answered his letter about a complete lack of enthusiasme for the idea and a diverisons of resources, suggesting instead that the Range was not the way forward due to her meagre air group and that the USN should pursue the largest air group reachable on the allocated tonnage instead (which was the goal with the Essex class). The Bureau of Construction and Repair however in 1940-41 as the war was on full swing, considered the feasability of converting fast passenger ships with short flight decks. By November 1940, the Chief of Naval Operations (CNO) confirmed SecNav when reporting the Chairman of the U.S.Maritime Commission that the characteristics of aircraft have changed in sauch a way no converted merchant vessel would be satisfactory as an aircraft carrier.
But some lowered ranks in the navy did not dropped the ball and “short-circuit” the hierarchy by directly calling President Franklin D. Roosevelt, a former naval officer, scretary of the navy, and always interested by it, actively enter the controversy. He pointed out that UK was now fighting a merciless war on the Atlantic against U-Boats and as many U.S.-built military aircraft arrived in leand-lease, as well as 50 destroyers, her urged the need for an escorting and aircraft-carrying ship for faster delivery rather than in the usual cargo crates. By mid-February 1941, Rear Admiral William F. Halsey wrote to CiC Adm. King:

“A previously stated expectation, that the Navy would be called upon to provide transport for Army aircraft, has now materialized in the current diversion of Enterprise and Lexington to transport 80 pursuit planes from the West Coast to Hawaii. To continue with primary reliance on aircraft carriers for such work, as is our present neces-sity, seriously endangers the availability of air-offensive power in the Fleet.”

Adm. Husband E. Kimmel endorsed it from his position as Commander, Aircraft Battle Force to the CNO. By October 21, 1940, the CNO received a memorandum from the President’s Naval Aide about testing the conversion of a merchant into an aircraft carrier. But it was bolder than just an aicraft taxi: It was to carry indeed 8 to 12 helicopters of the new Sikorsky type -not yet operational- or airplanes tailored for small decks and hangars. The idea of a quick conversion to spread an air cover ahead of convoys and detect U-Boats, dropping smoke bombs for the escorts to pick up.

The CNO on 30 December 1940 dediced to ask the chairman of the Maritime Commission to investigate this possibility. By 2 January they consulted their lists and found two refugee Danish ships offering such conversion capability. Later investigation however demented that prospect. The conference determined that the intended ships should be of standardized design for plans to be easily ported on mass-construction ships, and that the air group and types question should be further investigated.

They also estimated that defence should included four AA pom-poms and one 5-inches surface gun. But the converted merchant ship idea was definitely “in the tubes”. On January 6, 1941, Adm. Harold R. Stark, the current CNO, wanted a new conference in his Washington office to further discussed the matter. The autogiro type was soon eliminated (The IJN howewever will adopt it nevertheless) and that dropping smoke bombs only was a waste of time (as well as blimps). A better loaded aircraft with depht charges or bombs would be a better ASW proposal overall. The short deck idea was thus also dropped (This would not deter the Royal Navy to convert MACs (Merchant Aircraft Carriers)).

The meeting also concluded that diesel should bu used to eliminate smokestacks. The Maritime Commission was consulted for the conversion of C-3 cargo ships. They in response, answered that the Mormacmail and the Mormacland were suitable for conversion and available. This was reported to President Roosevelt and that a full conversion would last three months and acquisition was sanctioned on March 6, 1941. On June 2 was commissioned USS Long Island (AVG-1), and plans were made to convert the Mormacmail, but the Bureau of Aeronautics wanted a 350 feet deck to land its SOC SeaGulls. Long Island had a 362 feet deck, one elevator, a small hangar and 16 planes.

Mormacland was eventually sent to the RN as HMS Archer when completed by November 1941. Long Island essentually replaced USS Langley as a new test and training ship. It soon underlines the need of a broader deck and two elevators instead of one, as a longer flight, better AA and higher hangar. On December 26, 1941, the Secretary of the Navy approved the conversion of 24 merchant hulls as part of the 1942 shipbuilding program (The Bogue class). In March, her ordered the conversion of cruiser hulls (the ten CVLs or Independence class). However for large series, there were at the time only twenty C-3 hulls available for conversion and ten were already planned for the Royal Navy. Meanwhile USS Charger (CVE-30) tested more ideas andreplaced CVE-1 as training ship with closer caracteristics to the Bogues and subsequent CVEs.
The remaining four CVEs of the 1942 program were converted from Cimarron class fast fleet oilers (T3 class) later the Sangamon class, larger, with a larger flight deck of 503 feet by 85 feet, and enough hangar space to accomodate two small squadrons. They were rushed-completed for Operation Torch.

Meanwhile, the experience of the Atlantic convoy shed some light on possible CVE improvements, notably on carrier operations and tactics to adapt to the new U-Boats tactics, the placement of the catapult and elevators. Service experience with the Sangamon class brough some interresting returns. Reports were written on their daily used of TBF-1 Avengers, SBD-3 Dauntless and F4F-4 Wildcat in support of landing operations while in TF 34. Reports about their commitment in combat air patrol and anti-submarine patrols were noted.
All in all as commented the Atlantic Commander in Chief (CinCLant)

“The CVE’s proved to be a valuable addition to the Fleet. They can handle a potent air group and, while their speed is insufficient, thev can operate under most weather conditions and are very useful ships.”

. This report was not lost to Ernest King and revised his opinions.
This was balanced by Captain Calvin T. Durgin which reported:

“Due to their low speed, lack of protection and light armament, it is considered hazardous to employ a CVE group in operation where there is likely to be an effective enemy opposition.
Such a group can, however, be used to advantage, and is capable of inflicting substantial damage to the enemy in assault where the enemy air and sea opposition is negligible or when it is
being contained by other superior forces. When this situation exists, the CVE is well equipped to provide all support until landing strips are established ashore, and it can be effectively employed for bombardment spotting, combat air patrols over beaches and surface forces, for all forms of air reconnaissance missions and for bombing, rocket and strafing attacks.”

By the time the four Sangamons rejoined the Pacific at the end of 1942, the carried fleet was down to USS Enterprise and the Saratoga.
President Roosevelt before that announced new escort carriers would be built when visited by Shipbuilder Henry J. Kaiser. He impressed the President with his plan for mass production of escort carriers, a plan browing and under supervision by the Maritime Commission since early 1942.

Succession

USS Casablanca (CVE-55), the first of these, was commissioned July 8, 1943, leading a serie from CVE-55 to CVE-104. The order was complete by July 8, 1944, an impressive achievement. But the Sangamon class led to study a larger variant planned for the 1944 building program which became the first Navy-designed escort carriers for which hull and propeller model tests were carried out at the David W. Taylor Model Basin. The design was approved December 10, 1942 and the contract was let on January 23, 1943. The Commencement Bay (CVE-105) class was born. They measured 557 feet for a 19 knots speed, trial displacement of 23,100 tons. Most were commissioned just before V-J Day and incorporating all lessons learned since USS Long Island while the CVE type at large earned the respect of the Fleet by its service.
By December 13, 1944, the Escort Carrier Force, Pacific, was created and fell under command of RAdm. Durgin which evaluated the Sangamon class in North Africa. This was the result of the large number of escort carriers now available to the Fleet, thanks to the Casablanca class. Experience at Palau, Morotai and Leyte all pointed out better planning was necessary not to jeopardize their usefulness and unleash their full potential.
Scot MacDonald, based on reports by VADM. (THEN RADM.) Calvin T. Durgin, Commander, Escort Carrier Force, Pacific for NAVAL AVIATION NEWS, Dec. 1962. Src

About Henry J Kaiser

Henry John Kaiser (May 9, 1882 – August 24, 1967) was an American industrialist, “father of modern American shipbuilding”. He started in the construction industryand notably worked on the Hoover Dam. He formed Kaiser Aluminum and Kaiser Steel and later established the Kaiser Shipyards as a logical follow-up. Of course his most famous creation were the 2700+ Liberty ships of World War II, out-building what German U-Boats can sunk. After the war he turned to Kaiser Motors and the booming post-war automobile industry. He also diversified in the 1960s to other sectors.

Escort carriers fitting out at Kaiser Shipyards circa April 1944
Escort carriers fitting out at Kaiser Shipyards circa April 1944
Of course it’s for his shipyards Henry J Kaiser was best known.
The Kaiser Shipyard in Richmond, California became the fastest and largest ship producer in the world, but it was not done on a single day: Henry J. Kaiser had been building cargo ships for the U.S. Maritime Commission already by the late 1930s. After September 1939, he started to receive additional orders from the British government and knowing his capability would be soon overrun by orders he established his first Richmond shipyard, in December 1940.

This soon accompanied by an innovative medical care (later “Kaiser Permanente”). The four Richmond Kaiser Shipyards built 747 ships in World War II which was an unsurpassed industrial effort for shipbuilding. His ships became the world’s cheapest built in 2/3 less time and at 1/4 cost. Robert E. Peary was became the recold holder of faster ship of that size ever assembled, in less than five days (it was a state-sponsored competition among shipyards). All in all by 1945 the yard built $1.8 billion worth of ships.

He achieved this feat by adapting production techniques specific to cargo ship construction with an emphasis on hyper-standardization and taylorization at any level, with an average construction time of 45 days. The Liberty ships were succeeded by the faster Victory ships. He changed his assembly techniques by visiting Ford, which convinced him to swap to welding instead of riveting. Not only it took less strength (and thus, was a job open to women) and was easier to teach, especially for unskilled laborers. Sub-assembliy and modularity was also key in the process.

The choice of Kaiser/Vancouver yard


The success rate of the first led to the establishement of no less than three others shipyards, in Ryan Point (Vancouver), Columbia River (Washington state) and Swan Island (Portland, Oregon). He built also smaller vessels and one was turned in just 71 hours and 40 minutes at Vancouver yard on November 16, 1942.

Perhaps it’s no mystery that this was Kaiser/Vancouver which was chosen by Kaiser for his proposal to the president of a hundred Kaiser hulls converted as escort carriers, just reusing the techniques he mastered well, with assistance for the Navy for all the proper military fittings and installations. Although this was done in the completion phase.
The Vancouver Shipyard was an emergency shipyard, constructed along the Columbia River in Vancouver, Washington (not Canada !) for the U.S. Maritime Commission in 1942. The shipyard was located on the Pacific Northwest as the Oregon and Swan Island ones (both in Oregon). This yard started production in March 1942 over an area of 200 acres (81 ha) and five different types were delivered, but the most famous one by far were the Casablanca-class escort carriers, the yard’s largest “production line”. On Google Maps


Vanport, Oregon, nicknamed “Kaiserville” in 1943. This mushroom city was a feat of wartime public housing setup in Multnomah County.
This yard had a payroll of 38,000 workers which came mostly from Vanport, Oregon were considerable housing was raised to house the workforce in the area. In fact as it often happened in a yard built in such a “remote” location, a city practically emerged from the ground up, fed by additional personal and services dedicated to this workforce. The city was however almost destroyed by the 1948 Columbia River flood.
After the war, the Shipyard had no more orders (as the others in Oregon) and they were sold to Gilmore Steel for just $3.25 million.

At Kaiser Vancouver (now part of Portland subburbia), each new carrier was to be delivered as an “empty box” with a landing deck, catways, fittings for future sponsons, truncated exhausts, a wide and completely empty hangar and lift, and a small island with a lattice, also empty. The completion supervised by the Navy comprised all the electrical lighting and wiring, and basically everything above the main deck, so from the hangar floor.


“Wendy Welder” at Richmond Shipyards. Feats of rapid construction were far less impressive for escort carriers due to the higher level of technicity.

One problem with welded hulls which surfaced after presidential approval for construction, and was more obvious after the war, was the issue of brittle fracture. This caused the loss of some Liberty ships in cold seas: Under both heavy load, bad weather and welding defects, welds failed, and hulls cracked, sometimes in two. Minor changes and more rigid welding control was only implemented from 1947, eliminated Liberty ship losses until 1955.

Kaiser also took part in the Joshua Hendy Iron Works of Sunnyvale in California building the standard EC-2 triple expansion steam engines used on all Liberty ships (the Victories had turbines). This led to the establishement of California Shipbuilding Corporation.
Anyway, welding did not affected the escort carrier life as apparently no significant accident was ever recorded and the losses by gunfire (St Lô) or Kamikaze attacks (xxx) were due to regular battle damage and fire rather than any structural issue. None broke in two as the result of severe impacts.

Construction Challenges

Term of building of the first 10 ships was 241-287 days, last ships of the class were built in 101-112 days or three months and a half on average. This was less stellar than Liberty Ships, but for warship construction of that scale and role, totally unheard of (and never surpassed). For comparison, a Yorktown class carrier took four years, an Essex-class two and a half. The same pre-fabrication and sub-assembly lines were used in a “leaf-pattern” to feed the central assembly line where the hull was assembled. This part was the fastest, and close to Liberty ships’s average delivery rates. It was the completion part which took most time.
As indicated above, the “empty box” delivered to the Navy needed to received many additional systems. Sensitive aviation fuel lines needed to be properly installed and checked, as well as the holds containing ammunitions (from bullets to depht-charges bombs and rockets), the intercom tested as well as communications lines to the AA gunners, machinery and central operation, and all the electronic equipments around the radars, displays, etc. They needed to be carefully calibrated. Crews were far larger than on Liberty ships (62 on average, counting the gunners and navy personal) versus on escort carriers: 910–916 officers and men total, including 50–56 for the air group, pilots and maintenance crews alike. This was more than ten times and implied far more accomodations, food and amenities to setup.

Vancouver Shipyards production setup

The hull chosen was the S4-S2-BB3 type according to the Maritime Commission Board registry. This was not even a wartime, but a prewar (for the US) project and registration. The U.S. Maritime Commission type S4-S2-BB3 emerged in 1941 as the Atlantic Convoys developed as the will to participated to the British desperate chase for aircraft carrier superiority. Planners estimated that military air cover was a crucial component of convoy escort and devise a type of small escort carrier based on the more civilian C4 type. The latter were 4th in rank and largest generic cargo type (hence the “C”).

The C4 were inspired by a designed originally for the American-Hawaiian Lines in 1941, and by late 1941, plans were taken over by the US Maritime Commission which designed a dedicated cargo/troopships in 3 shipyards: Kaiser Richmond, CA Yard No.3 Kaiser Vancouver, WA and Sun SB & DD in Chester PA. These were the largest cargo ships ever designed by MARCOM, with a single screw steam turbine and 9,900 shp, capable of 17 knots. The S4 was equipped ironically with a VTE which seems a step back, but sturdy enough to procured a top speed two knots above, at 19 kts.
Internally by the Commission the S4 were also described as “Kaiser-built Escort Carriers, Special Attack ships, Operation Crossroads”.

According to Kaiser-Vancouver logs here is the detail:
Legend: Hull# | Original Name | Type | MC# | Delivery Date | Pennant and final name:


301 | HMS Ameer | S4-S2-BB3 | 1092 | Jul-43 | CVE 55, renamed Alazon Bay, later Casablanca, scrapped 1947
302 | Liscombe Bay | S4-S2-BB3 | 1093 | Aug-43 | CVE 56, torpedoed and lost in the Pacific 1943
303 | Alikula Bay | S4-S2-BB3 | 1094 | Aug-43 | CVE 57, renamed Coral Sea, then Anzio, scrapped 1960
304 | HMS Atheling | S4-S2-BB3 | 1095 | Aug-43 | CVE 58, renamed Anguilla Bay, later Corregidor, scrapped 1960
305 | HMS Atheling | S4-S2-BB3 | 1096 | Sep-43 | CVE 59, renamed Mission Bay, scrapped 1960
306 | Astrolabe Bay | S4-S2-BB3 | 1097 | Sep-43 | CVE 60, renamed Guadalcanal, scrapped 1960
307 | Bucareli Bay | S4-S2-BB3 | 1098 | Oct-43 | CVE 61, renamed Manila Bay, scrapped 1960
308 | HMS Begum | S4-S2-BB3 | 1099 | Oct-43 | CVE 62, renamed Natoma Bay, scrapped 1960
309 | Chapin Bay | S4-S2-BB3 | 1100 | Oct-43 | CVE 63, renamed Midway, later St. Lo, kamikazied and lost at Leyte Gulf 1944
310 | Didrickson Bay | S4-S2-BB3 | 1101 | Oct-43 | CVE 64, renamed Tripoli, scrapped 1960
311 | Dolomi Bay | S4-S2-BB3 | 1102 | Nov-43 | CVE 65, renamed Wake Island, kamikazied off Okinawa 1945, scrapped 1947
312 | Elbour Bay | S4-S2-BB3 | 1103 | Nov-43 | CVE 66, renamed White Plains, scrapped 1959
313 | HMS Emperor | S4-S2-BB3 | 1104 | Nov-43 | CVE 67, renamed Nassuk Bay, later Solomons, scrapped 1947
314 | Kalinin Bay | S4-S2-BB3 | 1105 | Nov-43 | CVE 68, damaged at Leyte Gulf 1944, scrapped 1947
315 | Kassan Bay | S4-S2-BB3 | 1106 | Dec-43 | CVE 69, scrapped 1960
316 | Fanshaw Bay | S4-S2-BB3 | 1107 | Dec-43 | CVE 70, damaged at Leyte Gulf 1944, scrapped 1959
317 | Kitkun Bay | S4-S2-BB3 | 1108 | Dec-43 | CVE 71, damaged off Mindoro 1945, scrapped 1947
318 | Fortaleza Bay | S4-S2-BB3 | 1109 | Dec-43 | CVE 72, renamed Tulagi, scrapped 1947
319 | Gambier Bay | S4-S2-BB3 | 1110 | Dec-43 | CVE 73, sunk by gunfire at Leyte Gulf 1944
320 | HMS Kedive | S4-S2-BB3 | 1111 | Jan-44 | CVE 74, renamed Nehetna Bay, scrapped 1960
321 | Hoggatt Bay | S4-S2-BB3 | 1112 | Jan-44 | CVE 75, scrapped 1960
322 | Kadashan Bay | S4-S2-BB3 | 1113 | Jan-44 | CVE 76, scrapped 1960
323 | Kanalku Bay | S4-S2-BB3 | 1114 | Jan-44 | CVE 77, renamed Marcus Island, scrapped 1960
324 | Kaita Bay | S4-S2-BB3 | 1115 | Feb-44 | CVE 78, renamed Savo Island, scrapped 1960
325 | Ommaney Bay | S4-S2-BB3 | 1116 | Feb-44 | CVE 79, kamikazied and scuttled off Mindoro 1945
326 | Petrof Bay | S4-S2-BB3 | 1117 | Feb-44 | CVE 80, scrapped 1959
327 | Rudyard Bay | S4-S2-BB3 | 1118 | Feb-44 | CVE 81, scrapped 1960
328 | Saginaw Bay | S4-S2-BB3 | 1119 | Mar-44 | CVE 82, scrapped 1960
329 | Sargent Bay | S4-S2-BB3 | 1120 | Mar-44 | CVE 83, scrapped 1959
330 | Shamrock Bay | S4-S2-BB3 | 1121 | Mar-44 | CVE 84, scrapped 1959
331 | Shipley Bay | S4-S2-BB3 | 1122 | Mar-44 | CVE 85, scrapped 1961
332 | Sitkoh Bay | S4-S2-BB3 | 1123 | Mar-44 | CVE 86, scrapped 1961
333 | Steamer Bay | S4-S2-BB3 | 1124 | Apr-44 | CVE 87, scrapped 1959
334 | Tananek Bay | S4-S2-BB3 | 1125 | Apr-44 | CVE 88, renamed Cape Esperance, scrapped 1961
335 | Takanis Bay | S4-S2-BB3 | 1126 | Apr-44 | CVE 89, scrapped 1960
336 | Thets Bay | S4-S2-BB3 | 1127 | Apr-44 | CVE 90, later LPH 6, scrapped 1967
337 | Ulitaka Bay | S4-S2-BB3 | 1128 | Apr-44 | CVE 91, renamed Makassar Strait, to be sunk as target 1959 but grounded and broke up
338 | Wyndham Bay | S4-S2-BB3 | 1129 | May-44 | CVE 92, scrapped 1961
339 | Woodcliff Bay | S4-S2-BB3 | 1130 | May-44 | CVE 93, renamed Makin Island, scrapped 1947
340 | Alazon Bay | S4-S2-BB3 | 1131 | May-44 | CVE 94, renamed Lunga Point, scrapped 1960
341 | Alikula Bay | S4-S2-BB3 | 1132 | May-44 | CVE 95, renamed Bismarck Sea, kamikazied and lost off Iwo Jima 1945
342 | Anguilla Bay | S4-S2-BB3 | 1133 | May-44 | CVE 96, renamed Salamaua, damaged in Lingayen Gulf 1945, scrapped 1947
343 | Astrolabe Bay | S4-S2-BB3 | 1134 | Jun-44 | CVE 97, renamed Hollandia, scrapped 1960
344 | Bucareli Bay | S4-S2-BB3 | 1135 | Jun-44 | CVE 98, renamed Kwajalein, scrapped 1960
345 | Chapin Bay | S4-S2-BB3 | 1136 | Jun-44 | CVE 99, renamed Admiralty Islands, scrapped 1947
346 | Didrockson Bay | S4-S2-BB3 | 1137 | Jun-44 | CVE 100, renamed Bougainville, scrapped 1960
347 | Dolomi Bay | S4-S2-BB3 | 1138 | Jun-44 | CVE 101, renamed Matanikau, scrapped 1960
348 | Elbour Bay | S4-S2-BB3 | 1139 | Jun-44 | CVE 102, renamed Attu, sold for scrap 1947 but resold as Gay, scrapped 1949
349 | Alava Bay | S4-S2-BB3 | 1140 | Jul-44 | CVE 103, renamed Roi, , scrapped 1947
350 | Tonowek Bay | S4-S2-BB3 | 1141 | Jul-44 | CVE 104, renamed Munda, scrapped 1960

Impact of the Casablanca class on the war

It cannot be overstated as much WW2 involved an industrial colossal effort, several times greater than WWI, the first large scale industrial global war, and unlike any conflict of the past. At least the cold war only asked an incremental, peacetime evolution were output was gradually overshadowed by quality. In WW2, this was a Darwinian prospect. By December 1941, the “free world” seemed defeated on all fronts. Tanks and planes were produced by tens of thousands to be thrown into the furnace, but also ships – not small boats, but very large ones, demultiplying air power, seemingly the great winner of WW2.

Fifty aicraft carriers was an unprecedented number for that kind of vessel, never surpassed so far. It can be argued that they were so fast-buult, so simplified and low-cost they became “consumable” carriers a bit like the Liberty ships from the same yards, built with the same techniques, and as promised, a batch of 50 joined the 143 aircraft carriers built in the United States during the war. Perhaps the closest and only comparable endeavour today are the US Burke class destroyers, by cost and complexity several fold above the capabilities of the nimbler carriers.

By bolstering air power at low coast and quickly, these “Jeep carriers” spared the already hard-pressed Essex-class and Independence class making the bulk of the offensive fast carrier force of the Vth fleet in 1943-45. They provided indeed air cover for the numerous amphibious fleets deployed in the island-hopping campaign of the pacific, but also supply fleets, vital to keep TF38/58 operational on the long run, and the long supply chain which needed escort since Pearl Harbor to the far outreach of the Pacific, down to the US shores.

These 50 escort carriers were also split and part (a small one however) also took part in the vital role of escorting convoys in the Atlantic, since ASW warfare’s best answered soon appeared to be aviation, not least because U-Boats were more easily spotted from the air (and strafe them), but also to shoot down the Luftwaffe’s long range spotting planes such as the Fw200 Condor. The fifty carriers played this unglamorous but vital part of operations until construction stopped in July 1944. After the war, there fortune were diverse, many were stricken outright, other as late as 1960-64, still used as specialized ships (like aviaton transport), and then joined the civilian market, converted as freighters.

Design of the Casablanca class

General construction

Casablanca in many respects reminded Bogue but had smaller displacement, two shafts and was faster. As a design basis the fast dry cargo carrier of S4-S2ВВ-3 type was used, but, unlike the predecessors, new carriers were built quite new, instead of earlier carriers converted from merchant hulls.

Powerplant


There were two propellers screws, on shafts driven by two Skinner Unaflow reciprocating, vertical quadruple expansion (9000 shp) steam engines. The final commercial evolution of the uniflow engine in the US was reached by the late 1930, up the early 1940s by the Skinner Engine Company from the Compound Unaflow Marine Steam Engine operating in a steeple compound configuration making it almost as efficient as a diesel. This was usual on car ferries on the Great Lakes and the Casablanca-class used two 5-cylinder Skinner Unaflow engines, but not steeple compounds.


They were fed by four Babcock & Wilcox boilers. These were the common marine type, with a main balloon and series of small tubes below for expansion, double-ended.
Total output was 9,000 shp (6,700 kW). This allowed a top speed of 19 knots (35 km/h; 22 mph). There was a provision onboard of 2,228 tons fuel oil (in addition of the 120,000 gallons/454,000 liters aviation gasoline) for a Range of 10,240 nmi (18,960 km; 11,780 mi) at 15 knots (28 km/h; 17 mph).
The exhaust pipes were not truncated but rather ducted to the sides, two each side amidship and far apart to better vent smoke above the deck, at an ideal height for dispersion, as the wind blew stronger just over the deck surface, propelling the fumes outwards of the ship.

Armament


ONI Rendition of the ship – schematics.
It relied on the same usual “troika” of USN vessels of that era, with a single stern 5 in (127 mm)/38 cal dual-purpose gun, two quad 40 mm (1.57 in) Bofors anti-aircraft guns, and twelve 20 mm (0.79 in) Oerlikon anti-aircraft cannons around the flight deck’s sponsons.

Main: stern single 5-in/38


5-in/38 in action on USS Hollandia, 1945
This standard piece of ordnance shared by the whole US Navy and seen much as the best of its kind (a true dual purpose). The only issue of the Casablanca design was it’s location, a headache for engineers. It was placed on the poop deck and only could cover the rear 180° arc, with the landing deck partly above. The second issue was the lack of a protective shield against strafing or shrapnel in a naval engagement. More

40 mm Mounts


The twin mounts -there was no room for quad ones- were located fore and aft of the flight deck. These twin mounts were just in practice halved quad mounts. All parts were interchangeable. They had hydraulic-coupled drives to avoid salt contamination. These Mark IV twin mountings were derived from the Dutch Hazemeyer triaxial mounting from the minelayer Willem van der Zaan which took refuge in Britain in 1940. It was a self-contained mounting with its own rangefinder, radar and analog computer. There were two Mark IV water-cooled guns using track/pinion for elevation and training and a Ward-Leonard system for auto-tracking. It was somewhat delicate to use on small ships exposed to water spray, so more comfortable at the height of the carrier’s flight decks. It seems that crews preferred to use the manual mode over the power mode. It could elevate 25 degrees per second at 90°. The rest of the specs were the same as the common 40 mm/56 Mark 2.
More

20 mm Mounts



Standard L70 Oerikon piece, single mount, shielded, and placed along the deck’s side galley. This changed overtime, but the usual plan was two single sponsons forward of the bridge (one each side), behind the twin Bofors covering the angles, and two others behind or abadft the island, then twin mount sponsons all along the deck aft. The usual figure was four of these either side, so eight for sixteen single mount, and four single sponson mounts. This was increased during the war, making more room for extra single or twin sponsons. There were also four directoros for the AA artillery located on either end of the ship, close to the Bofors mounts. More.

SC and SG Radars and other electronic equipments


The SC air search radar was standard on most small to medium ships of the USN. It was completed by an SG surface search radar.
The 100 Kw SC CXAM-type radar had a Pulse Width of 5 microsecond, 60 Hz frequency, 5rp scan rate and detection of a bomber 30 nm (60 km) away, of a battleship at 10 nautical miles (20 km), a destroyer at 3 nautical miles (6 km), which was the bare minimum, greatly improved with the SC-1.
The SG was also 1st-gen model, small cut parabola at the front of the lower platform of the derrick. It was a 50 Kw model with the pulse Repetition Frequency of 775, 800 or 825 Hz, 4/8/12 rpm frequency, and 15 nautical miles (30 km) aerial range 22/15 nautical miles (30 km) for a surface ship from a battleship to a destroyer.
Both were located on the derrick mast over the bridge.
Some units had their radar upgraded to SC-2 or SK (respectively) later in the war (1945).

Aircraft facilities


They were fitted with two inboard elevators and a single steam catapult installed at the forward end of the flight dekc, to the right (port) unlike the Essex class which had it to the right, but in conformity to earlier designs. There was a single hangar with safety sprinklers and a damage control CP. Like other designs of the time, the avgas tanks were buried deep into the hull. The elevators had not the same size, the aft one was larger to accomodate planes without wings folded. Both rectalngular with rounded edges, the forwards one was in the axis, turned the aft one across. In total they carried 27 planes less spares, although the limited hangar space could not allow much to be suspended under the roof.

Air group


East Aircraft FM-2, VC-2, USS White Plains 1944
Globally, this air group was more diverse was usually assumed. It was composed of the F4F GM Wildcat as main fighter, but in some cases the F4U Corsair was operated as the F6F Hellcat. The SBD Dauntless dive bomber (SBD-5) was more common as the TBF Avenger. For reconnaissance some had one or two Curtiss SOC Seagull, F4F-P Wildcat but more rarely the F4U-P Corsair and F6F-P Hellcat.
The air group varied in time and role: For thos kept for convoy escort in 1943, notably in the Atlantic, the ypical air group comprised nine F4F-8/FM-2 and ten up to 12 TBF-1/TBM-3 Avenger.
By August 1944, USS Kasaan Bay had aboard 24 F6F-5 and 7 F6F-3N, so a very specialized batch of Hellcats, including a heavy reconnaissance component. This was 31, presumably many were a “permament park” on deck.
By April 1945 USS Fanshaw Bay typically had the “standard” air group comprising twenty-four F4F-8/FM-2 for air defence and six TBM-3 for any surface/ASW threat, showing air defence was paramount, notably to protect the assault fleet against Kamikaze attacks.
USS Savo Island at the same time however had twenty F4F-8/FM-2 and 11 TBM-1C plus four TBM-3, mostly used for attacks, notably over Japan. The latter were gradually equipped with rockets, but consumed bombs as standard.

Fighters: General Motors FM-1/2 Wildcat

FM-1 Wildcat takes off from USS Kassan Bay in 1944
FM-1 Wildcat takes off from USS Kassan Bay in 1944

FM-2 VC-10 onboard USS Gambier Bay October 1944: She was sunk at the battle of Samar
FM2 1944
Eastern Aircraft FM-2, “judy” VC-14 USS Hogatt Bay (CV-75), Emirau Island (Bismarck Archipelago), May 1944.

Fighters: Grumman F6F Wildcat


F6F-5 taking off from USS Kasaan Bay off France, June 1944. The F6F was far less common aboard due to her larger size, and only adopted notably in some cases and missions, like landing cover, owing a possible appearance or enemy planes. Since it was far more rare for CVs escorting convoys, the nimbler Wildcat was the norm.

F6F-5 Hellcat VOF-1, USS Tulagi

Same as above, F6F from VF-74 from VCE-69, France 1944
Same as above, F6F from VF-74 from VCE-69, France 1944

Fighters: Vought F8U Corsair


F4U-4 Corsairs of VB-3, USS Solomons, making their qualifications in july 1945

Torpedo-Bombers: Grumman/GM TBM Avenger


Grumman TBF landing on USS Marcus Island, 5 March 1944. This was a first. This “juggernaut” became common as standard torpedo bomber, but in around 1/3 of the entire air group, completed by Wildcats most of the time. It was preferred over the Helldiver, but its large weight meant for taking off, it needed the whole deck lenght, and landing was always a more perilous exercize compared to roomy fleet carriers.

TBM-3 from VC-83, USS Sargeant Bay July 1945
TBM-3 from VC-83, USS Sargeant Bay July 1945


Douglas SBDs and Grumman TBFs on an escort carrier in 1943


TBM flies above USS Saginaw Bay, 14 June 1944

TBM Avenger catapult from USS Makin Island (CVE93), 1944
TBM Avenger catapult from USS Makin Island (CVE93), 1944

Dive-Bombers: Curtiss SB2C Helldiver


An SB2C on USS Kwajalein during a Typhoon in late 1944. The Helldiver was not liked much and if part in some occasions of CVE’s air groups, it was reserved for special operations and in particular in amphibious landing cover, both to deal with any ground objectives, but also with an always possible enemy fleet attack, as shown during the battle of Samar (Taffy 3 defence).
Unfortunately i can’t find a profile of one.

Reconnaissance: Curtiss SOC Seagull


The U.S. Navy escort carrier USS Savo Island (CVE-78) underway in May 1944, location unknown. Note dismantled SO3C Seamew, a J2F Duck (minus its engine), and SOC Seagull and three F6F Hellcats lining the port side, with spare floats lashed down aft.

Tactics and combat actions


Pilot Briefing aboard USS Kasaan Bay in 1944.
When the first of these ships were commissioned in the summer of 1943, the face of the war in the Pacific already had drastically changed, as the USN was no longer “hanging by the nails” with a few interwar careers and cruisers to stand up to the IJN. The first two Essex class fleet carriers just arrived and relieved this fatigued force centered around the battered USS Enterprise and Saratoga, as well as the first seven CVLs (Independence class) that brought a breath of fresh air to the US Forces, enabling to consider a steady counter-offensive.

A hard to fit new type

USS Casablanca (ACV-55) about to be launched on 5 April 1943
USS Casablanca (ACV-55) about to be launched on 5 April 1943

Tactically, discussion in the admiralty board, submitted with this unexpected mass-built design, had little doubts about its use. Too slow to take part in main combat operation with the fleet (That was the role attributed to the core of TF38/58) they were relegated to two other forces: The assault fleet, mostly comprising troopships and their escort, and the slower auxiliary fleet, supply and depot vessels, repair ships and oilers. Both were to be protected by the fast carrier fleet, taking a more active role allowed by its speed.

The bulk of the assault and auxiliary fleet was made of civilian-grade ships capable of 15 knots on average. Thus the 19 knots of the Casablanca were perfectly adequate. The seocnd point was about their air group. It was not large enough for the air naval doctrine at the time. The “100-planes assault” or “sunday punch” was the new norm for fleet carriers, enabling a better coordination. The CVLs were mostly there to provide a CAP and resupplying losses. But the small groups of the CVEs limited them to air defence, which was shown in the majority of their composition, which was mission-dependent. They usually had a full fighter squadron, but a half-squadron for attack.

For those potentially deployed in the Atlantic, a perhaps more balanced air group as envisioned, with the TBF Avenger used as main ASW patrol/strike plane. The Luftwaffe was not really a threat by late 1943 over this theater. But for the sake of standardization the Casablancas were kept for the Pacific, which was not the case for the Bogue class.


USS Guadalcanal in the Battle of the Atlantic: Its TBMs about to be launched for an attack on U-544. The combination 5-in rockets/depth charges was found the best in early 1944.

Thus, a distinction was made for those assigned to assault forces: Their air group in proportion comprised a more balanced ratio of attack planes versus fighters in order to participate to the air support during the assault. Something that partly freed the fast carrier force for more important objectives, preventing reinforcements and distant strike assets (like airfields on other islands) for example or diversionary actions. In short the CVEs provided the “close air support” for the invasion force, both a permament CAP in case of Japanese aircraft from other airfields/bases not neutralized by the fast carrier force (which happened often, with unexpected Kamikaze attacks), and direct and on-demand air support.

A place found and secured


USS Bismarck Sea CVE-95 loading Douglas SBD Dauntless bombers from a barge circa in 1944.


The initial role as planned early in 1941 by President Rooselevelt was a quick conversion of merchant vessels to taxi all sortts of aircraft delivered via lend-lease. They could simply be flown instead of delivered by crate, transported to an airfield, assembled and tested, which was the usual way in peacetime. The Casablanca class carried all sorts of aircraft types, including very large ones. Here USS Thetis Bay loaded with eight Catalinas and a dozen smaller types under their shadow.

When the first CVEs were starting their training, meanwhile in the Pacific the Invasion of New Georgia was near its completion (30 June-5 August 1943). This was the first major Allied offensive in the Solomon Islands after Guadalcanal, a closing point to the gruelling match that was ongoing since last August 1942 and seeing many battles. Also the operations they missed were the Gilberts invasion from 20 July 1943 at Tarawa and Abemama atolls, Nauru Island (Operation Galvanic).
It’s by the end of the year that most CVE were at last fully ready for combat, with their pilots qualified. The invasion of Makin Island in September (Marines landed from USS Nautilus) and the full invasion in November supported by the first CVEs, and among these, three Casablanca-class vessels, which air group was mostly intended for assault, with Douglas SBD Dauntless dive bombers and Grumman TBF Avengers. These were USS Liscome Bay, USS Coral Sea and USS Corregidor.

USS Liscome Bay
The former was the sole loss (and first of the class), spotted at dawn on 24 November by the Japanese submarine I-175, arriving unnoticed prior to the invasion and by a single torpedo hit off a full spread. The torpedo detonated just outside, blewing up its aerial bombs stockpile, trigerring a detonation that broke her in two, with 644 going down, including flagship admiral, TG commander Rear Admiral Henry M. Mullinnix and Captain Irving Wiltsie, plus Pearl Harbor Navy Cross recipient Cook Third Class Dorie Miller (with a new fleet carrier named after him). The latter investigation shown the destroyer screen composed of USS Hull and USS Franks were not in place when this happened and they were not zigzaging, to make support operations easier.

USS Anzio (CVE-57) at Pearl Harbor, 5 October 1944
USS Anzio (CVE-57) at Pearl Harbor, 5 October 1944

On the 15th, escort carriers provided direct support for landings on Mindoro and the next two days. By January 3-22, 1945 some 17 escort carriers covered the approach of the Luzon Attack Force as part of Task Group 77.4. They made preliminary strikes in the assault area and covered the landings, supported the inland advance. RAdm. Sample with six carriers, provided air cover and support at San Antonio (near Subic Bay) and by February, Adm. Durgin directed his carriers at Iwo Jima.

Damaged Hellcats F6F-5 aboard USS Admiralty Islands, 20 July 1944
Damaged Hellcats F6F-5 aboard USS Admiralty Islands, 20 July 1944

In March he commited his reinforced carrier group at the Okinawa campaign at the head of Task Group 52.1 (18 escort carriers). Missions included pre-assault strikes, occupation support of Kerama Retto, pre-assault strikes on Okinawa, landings support, CAP and ASW patrols, daily close support.

USS Gambier Bay under fore at Samar, 1944
USS Gambier Bay under fore at Samar, 1944

Losses of CVEs were not heavy according to WW2 standards. Five were lost in the Pacific and one Bogue class in the Atlantic. The losses were due mostly to unexpected attacks: Naval surprise for St Lô at Leyte, she never was supposed to deal with heavy warship gunfire, Kamikazes that went through or submarines sneeking in, classic loss clauses that had few remedies but better patrolling from escorting destroyers and heavier combined AA, better CAP tactics, or just avoiding negligence in the face of clever tactics as shown by the Taffy-3 case.

Camouflage Liveries

Camouflage Pattern MS-33 Design 3D for the Casablanca class
Camouflage Pattern MS-33 Design 3D for the Casablanca class.


Pattern sheet MS-33 10A


Pattern sheet MS-32 12A

Casablanca
Old author’s illustration of USS Casablanca in 1944. More recent ones ar coming, and a poster with the fifty carriers.


USS Liscome Bay, 1943


USS Guadalcanal, mid-1944


USS Shamrock Bay 1944-45


USS Bismarck Sea, 1944


USS Gambier Bay as she was when sunk at the battle of Samar in Taffy 3, Leyte October 1944.


USS Casabanca 1945

USS Casablanca (1942) specifications (to edit)

Displacement 8,188 t. standard -10 902 t. Fully Loaded
Dimensions 156.16 m long, 33 m wide, 6.32 m draft
Propulsion 2 shaft Skinner Unaflow turbines, 4 Babcock & Wilcox boilers
Speed 9,000 hp, 19 knots
Armament 1 x 5 in (127mm), 8 x 40 AA (4×4), 12 x 20 mm, 27 aircraft
Armor None
Crew Circa 860

The Casablanca class coldwar career (1946-1964)


USS Thetis Bay (CVHE-1) 1950s
A bunch of these carriers stayed active for a few more years after their initial decommission in 1946-47, which was the fate of all there fifty ships. With the war of Korea however an inspection commission examined those in the best general state to be refurbished and recommissioned, at least as aircraft/helicopter carriers/taxis.
There were:
USS Corregidor: Reactivated 19 May 1951 decomm. again 4 September 1958
Cape Esperance: Reactivated 5 August 1950, decomm. 15 January 1959
Thetis Bay: Reactivated 20 July 1956, decomm. 1 March 1964
Windham Bay: Reactivated 28 October 1950, decomm. 15 January 1959

First F-86s arrive in Korea on USS Cape Esperance, Nov 1950
First F-86s arrive in Korea on USS Cape Esperance, Nov 1950
USS Leyte CVA-32 and Reserve Fleet escort carriers at the South Boston Naval Annex 25 July 1953
USS Leyte CVA-32 and Reserve Fleet escort carriers at the South Boston Naval Annex 25 July 1953

Many were still around in 1958, in long preservation, and were simply discarded and scrapped or expended as targets like Makassar Strait in 1961.
Note: They will be the object of a separate article in the cold war section.

USS Thetis Bay (CVE-90) had the longest career, as from September 1945 she joined the “Magic Carpet” fleet, and by August 1946, joined the Tacoma group, Pacific Reserve Fleet.
She was reactivated from May 1955, leaving the Pacific Reserve Fleet, towed to the San Francisco Naval Shipyard to be converted under project SCB 122, the first USN assault helicopter carrier. On 1 July, she became CVHA-1, in support of attack transports for vertical assault capabilitie, recommissioned on 20 July 1956 with the aft section of her flight deck cut away. She trained with the Marine Corps Test Unit No. 1 in Camp Pendleton and taking part in amphibious training exercises off of the California coast.

The evaluation complete, she departed for the Far East on 10 July 1957. She would returned there in 1958. In 1959 she became LPH-6 and was repaired after Typhoon Billie while in Taiwan. She put to good use her 21 Marine Corps Sikorsky H-34s to ferry aid and transporting civilians after a massive flooding. Back in the US she took part in the first large-scale night landing of ground forces by carrier-based helicopters. She was back in the Pacific’s 7th fleet in 1961, and in 1962-63 operated off the Atlantic coast and Caribbean. She took part in the Cuban Missile Crisis‘s naval “quarantine” having a marine landing team ready for action. In late 1963 she helped Port-au-Prince after a storm, providing medical aid and food supplies.
In January 1964 she was sent to the Naval Inactive Ship Maintenance Facility in Philadelphia for inactivation work, struck 1 March 1964, sold by December 1964, BU 1966.

Gallery


A model of USS Gambier Bay

USS Sargent Bay CVE-83 underway 1944

US Navy escort carriers at San Diego circa in June 1944
USS Admiralty Islands CVE-99 ferrying planes 31 December 1944
USS Admiralty Islands CVE-99 ferrying planes 31 December 1944

Resources

Links

https://commons.wikimedia.org/wiki/Category:Casablanca_class_aircraft_carriers
https://en.wikipedia.org/wiki/Casablanca-class_escort_carrier
https://www.navypedia.org/ships/usa/us_cv_casablanca.htm
http://www.usmm.org/c4ships.html
https://www.maritime.dot.gov/taxonomy/term/51?page=2
https://www.oregonencyclopedia.org/articles/kaiser_shipyards/#.XDUjKs9KjjA
https://www.columbian.com/news/2013/aug/19/war-effort-clark-county-kaiser-shipyard/
http://shipbuildinghistory.com/shipyards/emergencylarge/kvancouver.htm
https://www.ibiblio.org/hyperwar/USN/ships/ships-mc.html#s4
http://www.hazegray.org/navhist/carriers/us_esc2.htm
https://www.navsource.org/archives/03/055.htm
https://www.navsource.org/archives/03/055co.htm
https://www.history.navy.mil/research/histories/ship-histories/danfs/c/casablanca.html
https://www.history.navy.mil/content/dam/nhhc/research/histories/naval-aviation/evolution-of-aircraft-carriers/car-9.pdf
https://www.history.navy.mil/content/history/museums/nmusn/explore/photography/ships-us/ships-usn-l/uss-lunga-point-cve-94.html
http://www.navsource.org/archives/03/063.htm
http://www.navsource.org/archives/03idx.htm
https://www.navysite.de/cve/cve55class.htm
https://uboat.net/allies/warships/class/110.html
https://tmg110.tripod.com/usn_cve.htm
http://pwencycl.kgbudge.com/C/a/Casablanca_class.htm
https://ww2db.com/ship_spec.php?ship_id=297
https://www.globalsecurity.org/military/systems/ship/cve-55.htm

Escort Carrier Program


https://nationalinterest.org/blog/reboot/how-casablancas-class-aircraft-carriers-shook-world-war-ii-188673
https://commons.wikimedia.org/wiki/Category:Casablanca_class_aircraft_carriers

Books

John Gardiner Conway’s all the words fighting ships 1921-47
The Escort Carrier in the Second World War: Combustible, Vulnerable, Expendable!, By David Wragg, page 180
Aircraft Carriers: A History of Carrier Aviation and Its Influence on World, Norman Polmar, page 160

The modeller’s corner

General query on scalemates.com
https://www.cybermodeler.com/naval/casablanca/casablanca_all.shtml
https://sdmodelmakers.com/casablanca-class-escort-carrier-model.html

Videos

The Casablanca class in action:


USS Lunga point in the Mndanao sea, 3 January 1945

US Navy ww2 USS Casablanca (CVE-55)


USS Casablanca at Puget Sound, July 1943, freshly completed.
Construction of this famous lead ship was awarded to Kaiser in Vancouver, Washington as seen, with a contract signed on 18 June 1942 and symbol given AVG-55, as she was already the 55th escort carrier ordered at this point for US alone.
On 20 August she became ACV-55, for “auxiliary”. Laid down on 3 November 1942 as originall (HMS) Ameer, via lend-lease she was known there MC hull 1092, first of 50 vessels, and there was a special ceremony with the director, company’s staff and many officials of the Maritime Commision and USN.
Note: I’ll spend a longer time on this one to showcase a typical career to the full. The next ships’s careers would be seen on a more succnt way.
On 23 February 1943, the second one, Liscome Bay, was transferred under lend-lease in place of ACV 55, and was renamed “Alazon Bay” (Alazan Bay in reality, Kleberg County, Texas) and changed again for Casablanca on 3 April 1942 as her sister was in between, renamed Lunga Point. Launched on 5 April that year, quickly built as promised, she was sponsored by no less than First Lady Mrs. Eleanor Roosevelt.

After a quick fitting out, always for that kind of ship, she was transferred to the Navy on 8 July and this time, officially commissioned on 15 July. Firts captain was Steven Ward Callaway. He was chosen as the one who will “write the book” for hundreds of captains on similars ships to follow.

It was however discovered during her sea trials a serious defect on her single propeller, both crippling speed and agility, so she was useless basically before being drydocked for replacement. Kaiser was not surprised in some ways as such teething problems were awaited; This ship was the first to hit water after all. For some time before being drydocked she was retained by the Navy as a training vessel in the Strait of Juan de Fuca, providing there too, a model of pilot certifications proper to these fifty carriers.

Until August 1944, she basically trained all carrier squadrons for the whole class and a training vessel for crews intended for the other Casablanca-class before commission, which took just two weeks between mastering the equipment and handle these. She also generatd tons of useful data on how she handled for prolonged periods at sea, general readiness and equipment’s use. Lessons learned were implemented on the fly on the new ships in construction;

By the summer of 1944 at last, USS Casablanca was drydocked to have her propeller corrected. Following certifications, she carried out at last her first war mission, departing on 24 August with personnel, airplanes, and aviation gasoline, from NAS Alameda (California), passing under the Golden Gate Bridge and off San Francisco before heading for Manus (Admiralty Islands). After a transport mission, taxiing aicraft and making at least her first long range mission she was back on 8 October 1944 to resume at Puget Sound her role as training carrier, as she was found quite valuable for the role. Due to this she had little occasion to see combat. She started to train pre-commissioning crews for the larger Commencement Bay-class also. A storm damaged her enough to need repairs in San Diego from 22 January 1945. On 12 February Captain John Lewis Murphy took command.

Back in the same role on 13 March, she was re-routed for a new transport mission, making a stop to Pearl Harbor, and proceeded to Guam, to unload part of her cargo, followed by another stop at Samar in the Philippines, but also Manus, and Palau. From 12 May she went back home to West Coast and her first overhaul, carrying bacl wounded personnel. They were mostly diverted to Pearl Harbor on 24 June. The summer of 1945 saw her transporting more personal and material to Pearl Harbor and Guam. While mud-way to the latter, the crew heard about Japan’s surrender.

By late 1945 she retook her old rolme as training carrier, providing pilot qualifications off Saipan and was later retrofitted into a troopship toparticipate in Operation Magic Carpet fleet, repatriating servicemen from around many locations in the pacific. She arrived in San Francisco on 24 September and was back in Pearl (September-October) for a second run to stopping at Espiritu Santo, Nouméa.

Her last run was between 8 December and 16 January 1946 (San Francisco-Yokohama). Back on the West Coast she departed on 23 January to Norfolk, and be mothballed in the Atlantic Reserve Fleet from 30 May 1946, then fully decommissioned on 10 June, struck on 3 July and sold on 23 April 1947 for scrap, to a Chester Company. Her active life had been of just three years, exemplifying the way the whole class was throught to be a quick wartime expedient and little else.

But the role she played out of harm was invaluable for the whole class, giving quick and efficient training on all crews, something few aicraft carriers procured in their active life but perhaps the British HMS Argus.

US Navy ww2 USS Liscombe Bay (CVE-56)

USS Liscome Bay underway in 1945
USS Liscome Bay underway in 1945
USS Liscombe Bay (CVE-56) was named after a bay on Adak Island, in the Aleutian Islands. She was commissioned in April 1943.
After commission she moved to San Diego and than took aboard 60 aircraft before proceeding to San Francisco followed by training operations. On 11 October 1943, she became flagship, Carrier Division 24 (Rear Admiral Henry M. Mullinnix). On the 14th she received her air group and departed for Pearl Harbor, arriving on 27 October. After additional drills she was sent to join the invasion fleet of Operation Kourbash as part of Task Force 52 (RADM Richmond K. Turner), to the Gilbert Islands, her first and last mission.

USS Liscome Bay supported the invasion of Makin and proceeded to various bombardments with her air group on 20 November until Tarawa and Makin were captured. For more than 72h, her air group provided constant close air support, bombing Japanese positions, making 2,278 sorties. As part of Operation Galvanic they strafed and bombed airbases, and were called for quick support in ground operations as well as providing CAP for the landing area. USS Liscome Bay stayed with the rest of her task force to support Marines still fighting on Butaritari, whereas the rest of the fleet retired.
The invasion scrambled Admiral Mineichi Koga to send four Japanese submarines preying southwest of Hawaii, five near Truk and Rabaul to the Gilberts. Nine Japanese submarines were underway, but soon six were lost.
On 23 November I-175 (Lieutenant Commander Sunao Tabata) arrived off Makin and spotted the three escort carriers. She approached from 20 mi (32 km) southwest of Butaritari at 15 knots while the TG was traveling in a circular formation, seven destroyers, USS Baltimore, USS Pennsylvania, New Mexico, Mississippi, surrounding the three carriers. Liscome Bay was just in the center. But due to the risk of collisions they were not zig-zagging.
At 04:34, 24 November the destroyer USS Franks investigated a signal beacon, dropped from a Japanese plane, creating a screen gap and soon radar operators on New Mexico spotted a small blip (I-175 CT as she dove into position) and flight quarters were sounded at 04:50, but the crew returned to routine general quarters at 05:05 as 13 planes were prepared for dawn launching, readied on the flight deck, fueled and armed. Seven more were in the hangar but not readied, still she had a lot ammunitions stored below decks. Just as the TG made its turn to the northeast USS Liscome Bay had her side exposed to I-175, which fired a spread of three Type 95 “long lance” torpedoes.

At 05:10, the starboard lookout reported the torpedo wake, but there was little to do. It struck behind the aft engine room just as the carrier was turning, a lucky hit which detonated the bomb magazine. The resulting explosion created daylight over the whole area, with a mushroom nearly half a mile high, engulfing the ship. Shrapnel rained down 5,000 yards (4,600 m) away all around. New Mexico, just 1,500 yards (1,400 m) off had a fire starting by falling flaming debris, a sailor on USS Coral Sea being hit by… a fire extinguisher from Liscome Bay. The mushroom cloud above the ship soon reached several miles while nobody could see USS Liscome Bay anymore.

Her stern had been detached, clean through by the force of the detonation, the aft engine room was flooded instantly, the hangar and flight decks were heavily damaged, the superstructure and radar antenna collapsed on it, while a wild fire was soon out of control in the forward part of the hangar, igniting every planes parked on the flight deck which exploded in turn or fell off the deck. Fire-main pressure was lost an no pumps or fire fighting equipments worked. Other ammunition dumps soon started to detonate one after the other while gasoline was spread on the surrounding waters, catching fire. Thus, those jumping into the water had to escape underwater.
At 05:33, she listed to starboard and sink rapidly with still 53 officers and 591 salors and personal aboard. The list included Captain Irving Wiltsie, Rear Admiral Henry M. Mullinnix, Doris Miller.
The rest of the task group started evasive maneuvers, and at 05:40, USS Morris, Hughes and Hull arrived to the rescue, only catching men dead or dying. At 06:10 USS Maury spotted two torpedo wakes, 15 yards (14 m) from her while USS New Mexico’s radar operator spotted another echo, Hull and Gridley chaging on it. Macdonough went back to rescue a few more survivors until 08:00. In all 272 survived, albeit badly burnt or injured by shrapnel. This was more casulaties than the entire Japanese garrison on Makin.
On 4 February 1944, I-175 was detected and sunk by USS Charrette and Fair.

US Navy ww2 USS Anzio (Coral Sea) (CVE-57)

USS Anzio (CVE-57), ex Coral Sea underway
USS Anzio (CVE-57), ex Coral Sea underway.
USS Anzio (CVE-57) was a Casablanca-class escort carrier of the United States Navy. The ship was named after the Battle of Anzio, a World War II battle in Italy. She was commissioned in March 1944 and served in the Pacific theater of operations during World War II.

Anzio first saw action during the Marianas campaign in June 1944, providing air support for the invasion of Saipan. The ship also participated in the Battle of Leyte Gulf in October 1944, where she provided air cover for the invasion of the Philippines.
In 1945, Anzio was assigned to the Western Pacific, where she took part in the Okinawa campaign. During this campaign, she was attacked by a kamikaze plane on April 12, 1945, but managed to avoid serious damage.
After the war, Anzio was used to transport US servicemen back home. She was decommissioned in April 1946 and later sold for scrap in 1959.

US Navy ww2 USS Corregidor (CVE-58)


USS Corregidor (CVE-58) was a Casablanca-class escort carrier of the United States Navy. She was named after the Battle of Corregidor, a significant battle fought during the early stages of World War II in the Pacific.

Corregidor was commissioned in May 1944 and initially served as an escort carrier for convoys in the Atlantic. In August of that year, she was transferred to the Pacific theater of operations and provided air support for the invasion of the Palau Islands in September.

The ship also participated in the Battle of Leyte Gulf in October 1944, where she provided air cover for the landing forces in Leyte. In November, Corregidor supported the landings at Ormoc Bay, and then took part in the invasion of Lingayen Gulf in January 1945.
After the end of the war, Corregidor was used to transport US servicemen back home. She was decommissioned in March 1946 and later sold for scrap in 1959.

US Navy ww2 USS Mission Bay (CVE-59)

USS_Mission_Bay
USS Mission Bay (CVE-59) was a Casablanca-class escort carrier of the United States Navy. She was commissioned in October 1944 and named after Mission Bay, a large man-made saltwater lagoon in San Diego, California.
During World War II, Mission Bay served in the Pacific theater of operations and participated in the invasion of the Philippines in December 1944. The ship also took part in the Battle of Okinawa in April 1945, where she provided air support for the landings and conducted anti-submarine patrols.
After the war, Mission Bay was used to transport US servicemen back home. She was decommissioned in June 1946 and placed in reserve. In 1951, the ship was reactivated and converted into an amphibious assault ship, redesignated as LPH-6. She served in the Korean War and the Vietnam War before being decommissioned in 1970 and sold for scrap in 1971.

US Navy ww2 USS Guadalcanal (CVE-60)

USS Guadalcanal underway 28 September 1944.
USS Guadalcanal underway 28 September 1944.
USS Guadalcanal (CVE-60) was a Casablanca-class escort carrier of the United States Navy. She was named after the Battle of Guadalcanal, a significant battle fought during the early stages of World War II in the Pacific.
Guadalcanal was commissioned in March 1944. In September of that year, she was transferred to the Pacific theater of operations and took part in the invasion of Leyte in the Philippines.
The ship also participated in the Battle of Leyte Gulf in October 1944, where she played a significant role in the sinking of the Japanese battleship Musashi. In January 1945, Guadalcanal took part in the invasion of Luzon in the Philippines and provided air support for the landings.
After the end of the war, Guadalcanal was used to transport US servicemen back home. She was decommissioned in January 1947 and later sold for scrap in 1959.

US Navy ww2 USS Manila Bay (CVE-61)


USS Manila Bay (CVE-61) was a Casablanca-class escort carrier of the United States Navy. She was named after the Battle of Manila Bay, a significant naval battle fought during the Spanish-American War in 1898.
Manila Bay was commissioned in May 1944. In December of that year, she was transferred to the Pacific theater of operations and took part in the invasion of Lingayen Gulf in the Philippines in January 1945.
The ship also participated in the Okinawa campaign, where she provided air support for the landings and conducted anti-submarine patrols. In July 1945, Manila Bay was present during the initial occupation of Tokyo Bay.
After the end of the war, Manila Bay was used to transport US servicemen back home. She was decommissioned in May 1946 and later sold for scrap in 1960.

US Navy ww2 USS Natoma Bay (CVE-62)


USS Natoma Bay (CVE-62) was a Casablanca-class escort carrier of the United States Navy. She was named after Natoma Bay, a small bay on the coast of California.
Natoma Bay was commissioned in July 1943 and initially served in the Atlantic, providing air support for convoys and conducting anti-submarine patrols. In November 1943, the ship was transferred to the Pacific theater of operations.
During World War II, Natoma Bay participated in a number of operations, including the Battle of the Philippine Sea, the invasion of Peleliu, and the Battle of Leyte Gulf. She also provided air support for the landings at Lingayen Gulf and Okinawa.
After the end of the war, Natoma Bay was used to transport US servicemen back home. She was decommissioned in March 1946 and placed in reserve. In 1951, the ship was reactivated and converted into an amphibious assault ship, redesignated as LPH-8. She served in the Korean War and the Vietnam War before being decommissioned in 1970 and sold for scrap in 1971.

US Navy ww2 USS St. Lo (CVE-63)


USS St. Lo (CVE-63) was named after the Battle of Saint-Lô during the Normandy Campaign, commissioned on 23 October 1943 as USS Midway and renamed on 10 October about the battle. She also freed the name for the Midway armored carrier class. She would be the first and last ship in the USN bearing that name. As USS Midway, she left Astoria in Oregon on 13 November 1943, made her sea trials, shakdown cruise, and went back to dry dock post-fixes on 10 April 1944. She made a new shakedown on the west coast and two trips to Pearl Harbor and one to Australia carrying aircraft. At last for her 4th trip she departed wit the Composite Squadron 65 (VC-65) and met Rear Admiral Gerald F. Bogan’s Carrier Support Group 1 in June 1944, ready for the Mariana Islands campaign. During the trip she covered the convoy and once arrived started a serie of airstrikes on Saipan with her FM-2 Wildcats claiming their first 4 kills, damagine one more dueing their combat air patrol (CAP).
On 13 July 1944, she was sent in Eniwetok, for replenishment and on the 23th she sailed for the invasion of Tinian wit the same combined air support and CAP plus ASW patrol (ASP), and operated off Tinian until returning for supplies at Eniwetok on 28 July.
USS Midway remained in Eniwetok Atoll until departing on 9 August for Seeadler Harbor, Manus, in the Admiralty Islands.

On 13 September, she ws assigned to TF 77 for the invasion of Morotai. Two days after her air group sorties for air strikes and close support of troops ashore until the 22th. In after a refueling she resumed air operations in the Palaus and was back to the new forward resupply base (FRB) in Seeadler Harbor on 3 October, learnign she had been renamed USS St. Lo. (probably with some frustration by the crew) Communication codes had to be changed but pennant remained the same. At least the crew was briefed after the Battle of Saint-Lô which happened on 18 July 1944. Soon, her career was to end, but nobody knew at the time. Her service has been relatively “cushy” without much Japanese opposition until then. But it’s ironic that she was lost just a couple of weeks under her new name.

St. Lo departed Seeadler Harbor on 12 October to take part in the invasion of Leyte with the same mission, convoy air coverage, air strikes on arrival, close air support, CAP and ASP. This commenced on 18 October. Her area of operation was Tacloban, northeast of Leyte under command of Rear Admiral Clifton Sprague in a unit known as “Taffy 3” (TU 77.4.3) with six other escort carriers of her class (including Gambier Bay) and three destroyers, four destroyer escorts as their only defence. St. Lo was off the east coasts of Leyte and Samar launching strikes on 18 to 24 October between concentratons, installations and airfields.

Before dawn, 25 October while about 60 mi east of Samar USS St. Lo launched four Avengers deployed in ASP and prepared her air group for the initial airstrikes of the beaches. The Battle started at 06:47. Her ASP would play a role in these events as it’s Ensign Bill Brooks, pilot of one of these TBF Avengers which first spotted and reported the large “Center Force” (Vice Admiral Takeo Kurita) approaching from the west-northwest, just 17 miles away. Lookouts on St. Lo also reported one of the famous “pagoda-like” superstructures on the horizon, likeli from IJN Kongo. A dedperate call was made by Rear Admiral Sprague which ordered Taffy 3 to turn south at full speed. But with only at best 19 kts, the carriers were not aboit the cut it. Kurita closed in and opened fire at 06:58.

Immediately all air groups engaged in ground support were redirected to Kurita’s force. They had to brave their AA and attacked them, using at best the surrounding rain squalls to hide and emerge for new passed, landing to resupply and taking off again with every ordnance they possesses. This went on with all available plane and with the order to proceed to Tacloban airstrip to rearm and refuel as carriers were now managing to dodge salvos, making landings impossible.

At 08:00, the heavy cruisers were racibg forward, closing in on USS St. Lo’s abnd closing by her port quarter, at 14,000 yd (13,000 m) when starting precision furing, while the carrier answered with her only 5 in (127 mm) gun (claiming three hits on IJN Tone).
There was a 90 minutes mayhem, only interrupted by desperate destroyers attacks and smoke cover. Kurita’s forward forces closed to 10,000 yd (9,100 m) bot on her port and starboard quarters straddling her when she was visible through smoke screens. Kurita’s efforts were marred by these smoke screens, destroyer and attacks combined, having suddenly to change course or dodge ordnance. Soon aicraft arrived from Taffy 2 too in the south, ans those of Taffy 1 were also ordered to arrive asap.

Eventually the IJN cruisers and destroyers broke off, turning tail at 09:20. At 10:50, as St.Lô seemed saved, the Shikishima “Special Attack” (Kamikaze) Unit entered the fray. For 40 minutes they targeted the six carries despite fierce AA opposition and except USS Fanshaw Bay, they were all hit. St Lo was hit by a single A6M2 Zero (presumably Lt. Yukio Seki) which crashed on her flight deck at 10:51, after been deviated from over USS White Plains by AA damage. The fighter was carrying a bomb which in effect penetrated the thin flight deck, exploding on the hangar port side, meeting countless aircraft being refueled and rearmed.


The world’s famous photo showing “St Lô explosion”. This was not the resulting explosion but the initial strike of the Kamikaze. She was rocked afterwards by a serie of equally violent deflagrations caused by the cookoff of so many ordnance in the hangar, fuelled by high-octane aviation gasoline. The first major explosion following created a fireball rising 300 feet above the flight deck with the largest object seen above that fireball being aft aircraft elevator, sent to 1,000 feet above. The photo (which was soon on life magazine cover) was taken by a combat cameraman aboard USS Kalinin Bay (CVE-68). It is now open source, part of the USN collection and library of congress collection. It has been featured in countless books and documentaries, as the most iconic picture of the Battle of Leyte.

Unsurpringly gasoline fire started, ingniting all fuel lines and live ammunition stockpiles causing secondary explosions, until reaching the torpedo and bomb magazine wich caused a massive deflagration, with a mushroom hundreds of feets high (as caught by a world-famous photo) which sealed the fate of USS St. Lo: She sank 30 minutes later, carrying with her 113. Of the rather numerous survivors fortunately, sadly 30 more would later die of their burning wounds. USS Heermann, John C. Butler, Raymond and Dennis picked up 434 survivors that day. More were rescued later. USS St. Lô was the only carrier to be lost after a Kamikaze attack that day. Today, the wreckage of St. Lo is a popular dive site off the coast of the Philippines, where she sank.

US Navy ww2 USS Tripoli (CVE-64)


USS Tripoli (CVE-64) was a Casablanca-class escort carrier of the United States Navy, named after the Battle of Tripoli during the First Barbary War.
Tripoli was commissioned in April 1944 and served in the Pacific theater of operations during World War II. She participated in the Battle of Leyte Gulf, providing air support for the landings in the Philippines, and later in the Battle of Okinawa.
After the end of the war, Tripoli was used to transport US servicemen back home. She was decommissioned in March 1946 and placed in reserve.

In 1950, Tripoli was recommissioned and served in the Korean War, providing air support for ground troops and conducting anti-submarine patrols. In 1958, the ship was converted into an amphibious assault ship, redesignated as LPH-10.

Tripoli served in the Vietnam War and was involved in the Mayaguez incident in 1975, where she provided support for the rescue of the SS Mayaguez, a US merchant ship seized by Khmer Rouge forces off the coast of Cambodia. She was decommissioned in 1995 and sold for scrap in 2000.

US Navy ww2 USS Wake Island (CVE-65)


USS Wake Island (CVE-65) was a Casablanca-class escort carrier of the United States Navy, named after Wake Island, a coral atoll in the Pacific Ocean.
Wake Island was commissioned in July 1944 and initially served in the Atlantic, providing air support for convoys and conducting anti-submarine patrols. In November of that year, she was transferred to the Pacific theater of operations.
During World War II, Wake Island participated in a number of operations, including the Battle of Iwo Jima and the Battle of Okinawa, where she provided air support for the landings.
After the end of the war, Wake Island was used to transport US servicemen back home. She was decommissioned in June 1946 and placed in reserve.
In 1954, Wake Island was transferred to the French Navy, where she served as Dixmude. She was decommissioned in 1960 and later scrapped.

US Navy ww2 USS White Plains (CVE-66)


USS White Plains (CVE-66) was a Casablanca-class escort carrier of the United States Navy, named after the city of White Plains, New York.
White Plains was commissioned in November 1944 and served in the Pacific theater of operations during World War II. She participated in the Battle of Okinawa, where she provided air support for the landings and conducted anti-submarine patrols.
After the end of the war, White Plains was used to transport US servicemen back home. She was decommissioned in February 1947 and placed in reserve.
In 1951, White Plains was recommissioned and served in the Korean War, providing air support for ground troops and conducting anti-submarine patrols. In 1955, the ship was transferred to the French Navy, where she served as Dixmude.
She was decommissioned in 1964 and scrapped in 1967.

US Navy ww2 USS Solomons (CVE-67)


The USS Solomons (CVE-67) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after the Battle of the Solomon Islands, which was fought in the Pacific Theater of World War II.
The USS Solomons was commissioned on December 23, 1943, and began its service as an escort carrier in the Atlantic Ocean, providing air support for convoys heading to Europe. In March 1944, the ship was transferred to the Pacific Theater, where it participated in the invasion of the Mariana Islands and provided air cover for the landings on Saipan, Tinian, and Guam.

In October 1944, the USS Solomons participated in the Battle of Leyte Gulf, which was the largest naval battle in history. The ship provided air cover for the Allied forces during the battle and was credited with shooting down several enemy aircraft.
After the war ended, the USS Solomons was decommissioned in March 1946 and placed in reserve. The ship was later reactivated during the Korean War and served as a transport vessel, carrying troops and supplies to the Korean Peninsula. The USS Solomons was finally decommissioned in May 1958 and was sold for scrap in 1960.

US Navy ww2 USS Kalinin Bay (CVE-68)


USS Kalinin Bay (CVE-68) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Kalinin Bay, a bay in Alaska.
USS Kalinin Bay was laid down on September 10, 1942, at the Kaiser Shipyards in Vancouver, Washington, and was launched on December 19, 1942. The ship was commissioned on March 27, 1943, with Captain Francis T. Ward as her commanding officer.
After completing her shakedown cruise, Kalinin Bay was assigned to Task Force 52, which provided air support for the invasion of the Marshall Islands. The ship then took part in the campaigns in the Marianas, Palau, and the Philippines, where she was credited with shooting down numerous enemy aircraft.

On November 25, 1944, Kalinin Bay was attacked by a kamikaze aircraft during the Battle of Leyte Gulf. The ship suffered heavy damage, with 13 crew members killed and 60 wounded. However, the ship’s crew was able to save the ship and return her to service.
After repairs, Kalinin Bay returned to the Pacific theater and participated in the Okinawa campaign. The ship was decommissioned on April 17, 1946, and was sold for scrap in 1947.
USS Kalinin Bay received six battle stars for her service during World War II.

US Navy ww2 USS Kassan Bay (CVE-69)

uss kassan bay
USS Kassan Bay (CVE-55) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Kasaan Bay, a bay in Alaska.
Kassan Bay was launched on May 1, 1943, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on August 23, 1943, with Captain William D. Sample as her commanding officer.

After completing her shakedown cruise, Kassan Bay was assigned to Task Force 52, which provided air support for the invasion of the Marshall Islands. The ship then took part in the campaigns in the Marianas, Palau, and the Philippines, where she was credited with shooting down numerous enemy aircraft.
In October 1944, Kassan Bay was part of Task Force 38, which supported the invasion of Leyte in the Philippines. During this time, the ship participated in the Battle off Samar, where she provided air support to the escort carriers and destroyers that were being attacked by a much larger Japanese force. Kassan Bay was credited with shooting down several enemy planes during this battle.

After the war, Kassan Bay was used to transport troops and equipment back to the United States. The ship was decommissioned on April 17, 1946, and was sold for scrap in 1947.
USS Kassan Bay received four battle stars for her service during World War II.

US Navy ww2 USS Fanshaw Bay (CVE-70)


USS Fanshaw Bay (CVE-70) was commissioned on December 22, 1943, and was named after Fanshaw Bay, a bay in Alaska. The ship was built by the Kaiser Shipbuilding Company in Vancouver, Washington.
After completing her shakedown cruise, Fanshaw Bay was assigned to Task Force 52, which provided air support for the invasion of the Marshall Islands. The ship then participated in the campaigns in the Marianas, Palau, and the Philippines, where she was credited with shooting down numerous enemy aircraft.

During the Battle off Samar in October 1944, Fanshaw Bay was part of Task Unit 77.4.3, which was composed of six escort carriers and their escorting destroyers. Despite being heavily outgunned by the Japanese force, the escort carriers and destroyers fought valiantly to protect the landing forces at Leyte. Fanshaw Bay was hit by a kamikaze during the battle but was able to continue her operations.
After the war, Fanshaw Bay was used to transport troops and equipment back to the United States. The ship was decommissioned on April 30, 1946, and was sold for scrap in 1947.
USS Fanshaw Bay received six battle stars for her service during World War II.

US Navy ww2 USS Kitkun Bay (CVE-71)


USS Kitkun Bay (CVE-71) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Kitkun Bay, a bay in Alaska.
Kitkun Bay was launched on February 5, 1944, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on April 1, 1944, with Captain Henry Farrow as her commanding officer.

After completing her shakedown cruise, Kitkun Bay was assigned to Task Force 58 and participated in the Mariana and Palau Islands campaign. She then provided air support for the Leyte and Luzon campaigns in the Philippines.
During the Battle off Samar on October 25, 1944, Kitkun Bay was part of Task Unit 77.4.3, which was composed of six escort carriers and their escorting destroyers. Despite being heavily outnumbered by the Japanese force, the escort carriers and destroyers fought fiercely to protect the landing forces at Leyte. Kitkun Bay was hit by a kamikaze during the battle, but her crew was able to contain the damage and keep the ship afloat.

After repairs, Kitkun Bay returned to action and participated in the Okinawa campaign. She also transported troops and supplies back to the United States after the war. The ship was decommissioned on May 1, 1946, and was sold for scrap in 1947.
USS Kitkun Bay received six battle stars for her service during World War II.

US Navy ww2 USS Tulagi (CVE-72)


USS Tulagi (CVE-72) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after the Battle of Tulagi, which took place during the Guadalcanal campaign in the Pacific.
Tulagi was launched on April 7, 1944, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on May 22, 1944, with Captain Walter H. Price as her commanding officer.

After completing her shakedown cruise, Tulagi was assigned to Task Force 38 and participated in the Philippines campaign, providing air support for the landings at Leyte and Luzon. She was then assigned to Task Force 58 and took part in the Okinawa campaign.
During the Battle of Okinawa, Tulagi’s aircraft were involved in numerous air strikes against Japanese positions on the island. She also served as a rescue ship for downed pilots and provided anti-submarine patrols to protect the fleet from enemy submarines.

After the war, Tulagi was used to transport troops and equipment back to the United States. The ship was decommissioned on April 5, 1946, and was sold for scrap in 1947.
USS Tulagi received two battle stars for her service during World War II.

US Navy ww2 USS Gambier Bay (CVE-73)


USS Gambier Bay (CVE-73) was named after Gambier Bay, a bay in Alaska. She was launched on November 22, 1943 at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on December 17, 1943, with Captain Hugh H. Goodwin Jr. as her commanding officer.
After completing her shakedown cruise off San Diego, Gambier Bay was assigned to Task Group 52.2. On 7 February 1944 she sailed with 400 troops embarked for Pearl Harbor, and later rendezvous off the Marshall island. Her escort was the destroyer USS Norman Scott. She was also a taxi, flying 84 replacement planes for USS Enterprise. Back to San Diego via Pearl Harbor she carried aircraft in need of repairs, and qualified carrier pilots to Southern California. On 1 May 1944 she departed again, this time to join Rear Admiral Harold B. Sallada at the head of TG 52.11 for the Marshalls and invasion of the Marianas.

USS Gambier Bay there was tasked of close air support during the initial landings, for the Marines on Saipan, 15 June 1944. Her air group looked for enemy gun emplacements and troops as well as vehicles, all targets of opportunity. On the 17th, her combat air patrol managed to repel an attack of 47 enemy planes. In addition to the plane shot down, her gunners claimed two of the three attacking her.
The feat was repeated the following day, and the antiaircraft fire of the entire task group was even more intense. In all the eight pilots from VC-10 (composited) shared kills with the rest of the carriers and repulsed the attack with no loss. USS Gambier Bay stayed off Saipan for more CAPs and close support for the Marines. At the same time took place the Battle of the Philippine Sea. USS Gambier Bay was also present next at Tinian (19–31 July) and then Guam, for the same missions, until 11 August.

Both the ship received maintenance and the crew rest in the Marshalls. But on 15–28 September she was back supporting the assault on Peleliu and Angaur in the Southern Palaus. They were next sent to Hollandia in New Guinea, and Manus Island in the Admiralties, as invasion of the Philippines commenced. She was screened by four destroyer escorts shared with USS Kitkun Bay, tasked of escorting the transports and landing ships to Leyte Gulf. Next she was detached to join the escort carrier task uniy from Rear Admiral Clifton A. F. Sprague which assembled on 19 September off Leyte.

This TU comprised six escort carriers, three destroyers, four destroyer escorts, and had the radio call sign “Taffy 3”. This would become the most famopus unit in the whole three-days battle of Leyte that followed. The total force comprised indeed three groups of six-carrier task units. They were tasked ot maintain air supremacy over Leyte Gulf, eastern Leyte while TF-58 (Halsey) was the more mobile element, ready to pounce on any Japanese intervention. The invasion commenced and their air group caused havoc on the shore and inland, between enemy airfields and supply convoys to troop concentrations. The troops next received constant close air support, while a combat air patrolwas maintained. As the battle commenced, Taffy 1 and 2 were off northern Mindanao and off the entrance to Leyte Gulf while “Taffy 3” was off Samar.

The Japanese Southern Force was destroyed on 25 October in the Surigao Strait, the center force in Sibuyan Sea a day before was attacked by US Planes from Halsey’s Third Fleet, but the carriers were sent north to intercept the decoy carriers (Northern Force) off Cape Engaño. But the ruse worked, as meanwhile the Center force (presumed defeated by Halsey) sneaked in, just reinforced during the night, and comprising now four battleships, six heavy cruisers, two light cruisers, 11 destroyers. They passed San Bernardino Strait by night in the fog, proceeded along the coast of Samar and arrived at dawn in Leyte Gulf under a mixed sky, with a visibility of circa 40,000 yards (37 km), with low overcast, occasional rain squalls.

“Taffy 3” was caught off guard and made an urgent call for help. The escort carriers steamed eastward, launch planes and turned south seeking concealment in a heavy squall. The combined air groups attacked with all they had, torpedoes, bombs, strafing, until their ammunition ran out, and even went to “dry runs” (dummy attacks) when ordnance was done, just to keep the enemy formation busy and dispersed, in order to delay the advance. This was one of the several feats of bravery, gallantry and ultimate commitment in this extraordinary “last stand”.

Smoke was laid down by the destroyers to cover the carrier’s escape. They ducked in and out of it and also playing with occasional rain to to engage the fleet at point-blank range. There were losses, but their torpedo runs bear fruit. They were umtimately ordered back to cover the carriers with more smoke. But the Japanese, faster than the escort carriers, soon caught up and started to spot their targets: USS Gambier Bay was fired on first, hit by several ships at once. He single poop 5-inch (127 mm) gun fired nevertheless at a cruiser, without visible results, while destroyers Heermann and Johnston made a run to try to repel the Japanese, they paid dearly for it, being straddled by IJN Yamato, with the largest guns of the war in a rare surface action.


USS Gambier bay in flames. IJN Tone or Chikuma can be seen closing in for the coup de grace (right).

USS Gambier Bay was ultimately set alight, and as shells splash down beside her at 08:20, a heavy shell hit right through her forward engine room. Only capable of 9 knots, it’s either the heavy cruiser IJN Chikuma, or Yamato or Kongō which claimed the fatal hits as she went to a crawl. Tone and Chikuma closed until they could brought their AA to bear and complete the carnage. Abandon ship was ordered, and she ultimately capsized at 09:07, sank at 09:11, but had still 800 survivors, rescued two days later by landing and patrol crafts, albeit Sharks took their toll. 147 of the crew was never seen again. The same battle saw the loss of her sister USS St. Lo, the destroyers USS Hoel, Samuel B. Roberts, and Johnston. USS Gambier Bay became the one and only US Navy aircraft carrier sunk exclusively by surface gunfire.

Nevertheless, her air group was completed by Aircraft from “Taffy 2” and by 09:25 signalmen saw the whole Japanese fleet retiring. The “miracle of Samar”. Her Squadron and those of “Taffy 2” claimed with the destroyer’s help, three enemy cruisers and a lot of damage to the others in Center Force. USS Gambier Bay would later receive four battle stars for her service, shared the presidential Unit Citation for Taffy 3 “for extraordinary heroism in the Battle off Samar”. Captain Walter V. R. Vieweg received the Navy Cross for “extraordinary heroism”. XO Richard R. Ballinger received the Silver Star “for conscious gallantry and intrepidity”.

US Navy ww2 USS Nehenta Bay (CVE-74)


USS Nehenta Bay (CVE-74) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Nehenta Bay, a bay in Alaska.
Nehenta Bay was launched on December 11, 1943, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on February 3, 1944, with Captain Donald J. Ramsey as her commanding officer.
After completing her shakedown cruise, Nehenta Bay was assigned to Task Group 52.2, which provided air support for the invasions of the Marshall Islands and the Marianas Islands. She then participated in the Battle of Leyte Gulf, providing air support for the landing forces at Leyte.

After the war, Nehenta Bay was used to transport troops and equipment back to the United States. The ship was decommissioned on March 27, 1946, and was placed in the Pacific Reserve Fleet.
In 1951, Nehenta Bay was reactivated and converted into an escort aircraft carrier (CVC-74). She was then assigned to the Pacific Fleet and participated in the Korean War, providing air support for ground forces and conducting anti-submarine patrols.

Nehenta Bay was decommissioned for the second time on March 1, 1955, and was sold for scrap in 1959.
USS Nehenta Bay received two battle stars for her service during World War II and one battle star for her service during the Korean War.

US Navy ww2 USS Hoggatt Bay (CVE-75)


USS Hoggatt Bay (CVE-75) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Hoggatt Bay, a bay in Alaska.
Hoggatt Bay was launched on January 18, 1944, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on March 11, 1944, with Captain Joseph J. Clark as her commanding officer.

After completing her shakedown cruise, Hoggatt Bay was assigned to Task Group 52.2, which provided air support for the invasions of the Marshall Islands and the Marianas Islands. She then participated in the Battle of Leyte Gulf, providing air support for the landing forces at Leyte.
Hoggatt Bay was also involved in the Battle of Okinawa, providing air support for ground forces and conducting anti-submarine patrols.

After the war, Hoggatt Bay was used to transport troops and equipment back to the United States. The ship was decommissioned on April 3, 1946, and was placed in the Pacific Reserve Fleet.
In 1951, Hoggatt Bay was reactivated and converted into an escort aircraft carrier (CVC-75). She was then assigned to the Pacific Fleet and participated in the Korean War, providing air support for ground forces and conducting anti-submarine patrols.

Hoggatt Bay was decommissioned for the second time on March 1, 1955, and was sold for scrap in 1959.
USS Hoggatt Bay received two battle stars for her service during World War II and one battle star for her service during the Korean War.

US Navy ww2 USS Kadashan Bay (CVE-76)


The U.S. Navy escort carrier USS Kadashan Bay (CVE-76) at San Francisco, California (USA), on 8 April 1945. She is painted in Camouflage Measure 21. Several Lockheed PV patrol bombers are carried on deck.
USS Kadashan Bay (CVE-76) was a Casablanca-class escort carrier that served in the United States Navy during World War II. The ship was named after Kadashan Bay, a bay in Alaska.
Kadashan Bay was launched on February 22, 1944, at the Kaiser Shipyards in Vancouver, Washington, and was commissioned on April 15, 1944, with Captain Miles T. McGettigan as her commanding officer.

After completing her shakedown cruise, Kadashan Bay was assigned to Task Group 52.2, which provided air support for the invasions of the Marshall Islands and the Marianas Islands. She then participated in the Battle of Leyte Gulf, providing air support for the landing forces at Leyte.
Kadashan Bay was also involved in the Battle of Okinawa, providing air support for ground forces and conducting anti-submarine patrols.
After the war, Kadashan Bay was used to transport troops and equipment back to the United States. The ship was decommissioned on June 1, 1946, and was placed in the Pacific Reserve Fleet.

In 1951, Kadashan Bay was reactivated and converted into an escort aircraft carrier (CVC-76). She was then assigned to the Pacific Fleet and participated in the Korean War, providing air support for ground forces and conducting anti-submarine patrols.
Kadashan Bay was decommissioned for the second time on March 1, 1955, and was sold for scrap in 1959.
USS Kadashan Bay received two battle stars for her service during World War II and one battle star for her service during the Korean War.

US Navy ww2 USS Marcus Island (CVE-77)


The USS Marcus Island (CVE-77) was an American aircraft carrier that served during World War II. She was named after Marcus Island, a small island in the western Pacific Ocean.
The ship was originally designed as a merchant tanker, but was converted into an escort carrier during construction. She was commissioned in November 1944 and served in the Pacific theater of the war, primarily providing air support for the Allied forces during the Battle of Okinawa.

The Marcus Island was part of Task Group 52.1, which was responsible for providing air cover for the amphibious forces landing on Okinawa. Her aircraft were used for reconnaissance, fighter cover, and ground attack missions.
After the war, the Marcus Island was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1959, she was sold for scrap.
During her service, the Marcus Island was awarded two battle stars for her participation in the Battle of Okinawa and the assault and occupation of Okinawa.

US Navy ww2 USS Savo Island (CVE-78)


The USS Savo Island (CVE-78) was an American escort carrier that served during World War II. She was named after the Battle of Savo Island, a naval battle fought in 1942 during the Guadalcanal Campaign.
The Savo Island was commissioned in April 1944 and served in the Pacific theater of the war. She was assigned to Task Group 52.1, which was responsible for providing air support for the amphibious forces landing on the islands of the Pacific.
The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Savo Island participated in the Battle of Leyte Gulf in October 1944, providing air support for the American fleet during the largest naval battle of the war.
After the war, the Savo Island was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1959, she was sold for scrap.
During her service, the Savo Island was awarded two battle stars for her participation in the Battle of Leyte Gulf and the assault and occupation of Okinawa.

US Navy ww2 USS Ommaney Bay (CVE-79)


Ommaney Bay, after an area at the south end of Baranof Island, Alaska which was part of the Aleutian campaign, was commissioned on 11 February 1944 with Commodore Howard L. Young in command.
She had her sea trials, tests and fitting out at Astoria in Oregon, before a shakedown in Puget Sound and sailed on 19 March 1944 from Oakland to Brisbane in Australia, with passengers and cargo, including many replacement aircraft. On 27 April she was back in San Diego and started qualification of her own air group for ten days, with fleet drills. She had a few more alterations and repairs, until heading on 10 June for Pearl Harbor. Until 12 August she trained there before heading for Tulagi prepared for the invasion of the Palau Islands. From 11 September until early October she started combat operations off Peleliu and Angaur. On 18 September one of her TBM-1C short of on fuel landed onto Peleliu’s airfield, the first to do so, as troops were still securing the surroundings.

Next, the carrier was back in Manus Island for rest and dsplenishment, before reassigned to Rear Admiral Felix Stump and his TU 77.4.2 also known by its radio code “Taffy 2” on 22 October. In the south of Samar, started the invasion support operations. However on 25 October, 01:55, Admiral Thomas C. Kinkaid ordered the carriers to start reconnissances for any possibke IJN attack in a wide area around the invasion fleet at daybreak. Ommaney Bay took two hours to launch five fighters, seven torpedo bombers and they missed Vice-Admiral Takeo Kurita Center Force sneaking in. Where they were sent, they could have warned Taffy 3 well in advance and completely modify the battle. As the combat started, Taffy 2 soon rushed to help Taffy 3. Her airgroup has been credited with badly damaging IJN Chokai.

At 08:20, five Wildcats, six Avengers from Ommaney Bay attacked Mogami and also damaged her. 40 minutes later the Avengers joined 17 others crippling and sinking her for good three hours later as she was torpedoed by Akebono. This day saw the cxarrier launching six succesive attacks on the Japanese fleet with the rest of TG 77.4.1, largely responsible to turn the tide of a desperate fight. They appeared to have been more successful than destroyers, and fully confirming the navy that despite their small size, the escort carriers still could muster as much forces as any fleet carrier with the same effect if needed. Taffy 2 accepted aircraft from Taffy 3 due to the lost Gambier Bay and St Lo notably, or just low of fuel. She had to jettison her own aircraft to keep her flight deck operational. On 30 October, the battered, but victorious force retired for Manus, staying there for the most of November.

On 10 November as Ommaney Bay was docked in Seeadler Harbor, five miles (2.4 km) from the ammunition ship Mount Hood, she was suddenly rocked by the accidental explosion of the latter, one of the fiercest man-mande explosion in history. Sailors on deck were lifted off their feet by the blast, causing injuries, and soon after, compounded by the tidal wave provoked by the deflagration. While flamed fragments rained down, they oblied the safety crew to rapid extinguishing any start. On 12-17 December she was sent for various missions in Mindanao and the Sulu Sea for the invasion of Mindoro.

On 15 December the force was assaulted by 40 Japanese planes, kamikazes and escorts which came from former Clark Field and Davao, first reported at 7:00. The attack went on at 09:40, with one plunging with a bomb on Ommaney but missed, disengaging, two more missed and were shot down by Manila Bay and destroyer escorts. A single Yokosuka P1Y kamikaze however soon dove on Ommaney Bay from her port-bow side. The combined, directed AA fire from all ships eventually set it aloght 400yds (370 m) away and it crashed in the ocean, barely 27 m away. On 19 December she was back in respenihment. On 27 December she retutned for the landings at Lingayen Gulf, stopping at San Pedro Bay, and heading for the Sulu Sea on 3 January 1945.

On the afternoon of the following day, 4 January 1945 at 17:00 while underway in the Sulu Sea, her radar operator spotted 15 approaching Japanese planes 45 miles (72 km) away to the west, soon splitting into two groups to the rear and cented of the task group. All fighters were soon in the air, but their direction was plagued by false radar signals. In fact only army P-47 fighters intercepted and shoot down one. The one that escaped is believed to have sunk Ommaney Bay. This interception was not reported and at 17:12, a Yokosuka P1Y flying very low emerged and climbed, aiming at Ommaney Bay, approaching towards her bow. Captain Young confirmed the pilot was perfectly aware of his concelment, arriving in the blinding glare of the sun.

There were ten lookouts assigned on the island’s top open bridge with polaroid glasses in addition to the one on the signal platform. Without radar concept, the nearby USS New Mexico was was unable to react fast enough, when the plane arrived by complete surprise, slicing across the superstructure with its wing, which had everyone in the island plunging. Veering into the the flight deck, forward starboard side it released two bombs, one penetrating, detonating, and trigerring a serie of explosions. The second one crossed the hangar deck, rupturing the fire main and explosing in her starboard side. Water pressure forward lost, power, communications complicated matters, as the fire was now spreading fast thanks to a reuptured oil tank. The smoke became so thick all hope to combat fire in the hangar was abandoned.

Destroyers hesitated to close on Ommaney Bay to assist because of how firced and hot was the fire, knownin there was still plenty of ammunition aboard that can cookoff. After all, she was underway for an operation, at full ordnance capacity. USS Bell managed to get close enough to help fight fires with her pumps but collided. She started to evacuate the wounded at 17:45 but a few minutes afterwards the topside was just too hot. Stored torpedo warheads were signalled in the area which might be caught up by flames, and under threat to detonate when it was ordered to abandon ship. At 18:12, Captain Young was the last man to evacuate and an 18:18 as predicted, a fierce detonation followed, which collapsed the flight deck, projecting debris for miles around. She was scuttled by torpedoes at 19:58 from USS Burns. 95 sailors from Ommaney Bay were lost that day, plus 65 wounded. 7 more were killed during another kamikaze attack later. USS Shamrock Bay took her place for the operation in Lingayen Gulf.

Ommaney Bay burning after the attack
Ommaney Bay burning after the attack (cropped)
The loss of Ommaney Bay highlighted the vulnerability of these escort carriers, not protected unline Independence and Essex class, to these types of attacks. This led the command to develop more effective countermeasures. But by all acounts the pilot of the Yokosuka P1Y was probably a veteran that knew perfectly what he was doing and achieved complete surprise, and success.
For her service USS Ommaney Bay was awarded one battle star.

US Navy ww2 USS Petrof Bay (CVE-80)


The USS Petrof Bay (CVE-80) was an American escort carrier that served during World War II. She was named after Petrof Bay, a bay on the coast of Alaska.
The Petrof Bay was commissioned in February 1944 and served in the Pacific theater of the war. She was assigned to Task Group 52.3, which was responsible for providing air support for the amphibious forces landing on the islands of the Pacific.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Petrof Bay participated in the Battle of Leyte Gulf in October 1944, providing air support for the American fleet during the largest naval battle of the war.
After the war, the Petrof Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1960, she was sold for scrap.
During her service, the Petrof Bay was awarded four battle stars for her participation in the Leyte Gulf landings, the Mindoro landings, the Lingayen Gulf landings, and the assault and occupation of Okinawa.

US Navy ww2 USS Rudyard Bay (CVE-81)


The USS Rudyard Bay (CVE-81) was an American escort carrier that served during World War II. She was named after Rudyard Bay, a bay on the coast of Alaska.
The Rudyard Bay was commissioned in March 1944 and served in the Pacific theater of the war. She was assigned to Task Group 77.4, which was responsible for providing air support for the Allied forces during the Battle of Okinawa.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Rudyard Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Rudyard Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1960, she was sold for scrap.
During her service, the Rudyard Bay was awarded one battle star for her participation in the assault and occupation of Okinawa.

US Navy ww2 USS Saginaw Bay (CVE-82)


The USS Saginaw Bay (CVE-82) was an American escort carrier that served during World War II. She was named after Saginaw Bay, a bay on the eastern coast of Michigan.
The Saginaw Bay was commissioned in June 1944 and served in the Pacific theater of the war. She was assigned to Task Group 77.4, which was responsible for providing air support for the Allied forces during the Battle of Okinawa.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Saginaw Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Saginaw Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1959, she was sold for scrap.
During her service, the Saginaw Bay was awarded three battle stars for her participation in the Leyte Gulf landings, the Mindoro landings, and the assault and occupation of Okinawa.

US Navy ww2 USS Sargent Bay (CVE-83)


The USS Sargent Bay (CVE-83) was an American escort carrier that served during World War II. She was named after Sargent Bay, a bay on the coast of Alaska.
The Sargent Bay was commissioned in July 1944 and served in the Pacific theater of the war. She was assigned to Task Group 38.3, which was responsible for providing air support for the Allied forces during the Battle of Leyte Gulf.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Sargent Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
On December 13, 1944, while supporting the invasion of Mindoro in the Philippines, the Sargent Bay was hit by a kamikaze attack. The resulting explosion and fires caused the ship to sink within an hour, with the loss of 87 crew members.

The Sargent Bay was the second American aircraft carrier to be sunk by a kamikaze attack. Her loss highlighted the vulnerability of American carriers to these types of attacks, and led to increased efforts to develop effective countermeasures.
For her service in World War II, the Sargent Bay was awarded two battle stars.

US Navy ww2 USS Shamrock Bay (CVE-84)


The USS Shamrock Bay (CVE-84) was an American escort carrier that served during World War II. She was named after Shamrock Bay, a bay on the coast of Alaska.
The Shamrock Bay was commissioned in August 1944 and served in the Pacific theater of the war. She was assigned to Task Group 77.4, which was responsible for providing air support for the Allied forces during the Battle of Okinawa.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Shamrock Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Shamrock Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1960, she was sold for scrap.
During her service, the Shamrock Bay was awarded two battle stars for her participation in the assault and occupation of Okinawa and the Third Fleet operations against Japan.

US Navy ww2 USS Shipley Bay (CVE-85)


The USS Shipley Bay (CVE-85) was an American escort carrier that served during World War II. She was named after Shipley Bay, a bay on the coast of Alaska.
The Shipley Bay was commissioned in September 1944 and served in the Pacific theater of the war. She was assigned to Task Group 38.3, which was responsible for providing air support for the Allied forces during the Battle of Leyte Gulf.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Shipley Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Shipley Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1960, she was sold for scrap.
During her service, the Shipley Bay was awarded two battle stars for her participation in the Leyte Gulf landings and the Mindoro landings.

US Navy ww2 USS Sitkoh Bay (CVE-86)

uss sitkoh bay
The USS Sitkoh Bay (CVE-86) was an American escort carrier that served during World War II. She was named after Sitkoh Bay, a bay on the coast of Alaska.

The Sitkoh Bay was commissioned in October 1944 and served in the Pacific theater of the war. She was assigned to Task Group 38.3, which was responsible for providing air support for the Allied forces during the Battle of Leyte Gulf.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Sitkoh Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Sitkoh Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet.

US Navy ww2 USS Steamer Bay (CVE-87)

uss steamer bay
USS Steamer Bay (CVE-87) was an American escort carrier that served during World War II. She was named after Steamer Bay, a bay on the coast of Alaska.

The Steamer Bay was commissioned in November 1944 and served in the Pacific theater of the war. She was assigned to Task Group 38.3, which was responsible for providing air support for the Allied forces during the Battle of Leyte Gulf.

The ship’s aircraft were used for a variety of missions, including reconnaissance, fighter cover, and ground attack. The Steamer Bay was also used as a transport ship, carrying troops and supplies to various locations in the Pacific.
After the war, the Steamer Bay was used to transport American troops back to the United States. She was decommissioned in 1946 and placed in the reserve fleet. In 1960, she was sold for scrap.
During her service, the Steamer Bay was awarded two battle stars for her participation in the Leyte Gulf landings and the Mindoro landings.

US Navy ww2 USS Cape Esperance (CVE-88)


USS Cape Esperance (CVE-88) was named after the Battle of Cape Esperance, which took place during the Guadalcanal Campaign in 1942.
The Cape Esperance was commissioned on February 8, 1944, and completed her shakedown cruise in April of that year. She then joined the Pacific Fleet and participated in the Marianas Campaign, supporting the invasion of Saipan, Guam, and Tinian.
In October 1944, Cape Esperance took part in the Battle of Leyte Gulf, one of the largest naval battles in history. During the battle, she was part of the escort carrier group Taffy 3, which was attacked by a much larger Japanese force. Despite being heavily outnumbered, Taffy 3’s carriers and escorts fought back fiercely, and their actions helped to turn the tide of the battle in favor of the Allies.
After the war, Cape Esperance was decommissioned in June 1946 and placed in reserve. She was later transferred to the Maritime Administration and sold for scrapping in 1971.

US Navy ww2 USS Takanis Bay (CVE-89)

US Navy ww2 USS Thetis Bay (CVE-90)

USS Thetis Bay (CVE-90) Photographed on 7 August 1944. The ship is painted in Camouflage Measure 33, Design 10A. Photograph from the Bureau of Ships Collection in the U.S. National Archives.

USS Thetis Bay underway on 7 August 1944. The ship is painted in Measure 33, Design 10A camouflage
USS Thetis Bay (CVE-90) was named after Thetis Bay, located in the Aleutian Islands.
Thetis Bay was commissioned on March 15, 1944, and served in the Pacific Theater of Operations during World War II. She participated in several major campaigns, including the Battle of Leyte Gulf, where she provided air support for the invasion of the Philippines.
After the war, Thetis Bay was used to transport troops and equipment back to the United States as part of Operation Magic Carpet. She was decommissioned on April 15, 1946, and placed in reserve.
Thetis Bay was later recommissioned on July 20, 1950, in response to the Korean War. She served as an aircraft transport and helicopter carrier during the conflict, earning three battle stars for her service.
After the war, Thetis Bay continued to serve in various roles, including as a training ship and as a transport for military personnel and equipment. She was finally decommissioned on January 15, 1964, and sold for scrap in 1965.

US Navy ww2 USS Makassar Strait (CVE-91)


CVE 90 and 91 in dock, 1954
USS Makassar Strait (CVE-91) was named after the Battle of Makassar Strait, a naval battle fought between the Allied and Japanese navies in 1942.
Makassar Strait was commissioned on April 15, 1944, and served in the Pacific Theater of Operations during World War II. She participated in several major campaigns, including the Battle of Leyte Gulf and the Battle of Okinawa, where she provided air support for ground forces.
After the war, Makassar Strait was used to transport troops and equipment back to the United States as part of Operation Magic Carpet. She was decommissioned on June 27, 1946, and placed in reserve.
Makassar Strait was later recommissioned on August 10, 1950, in response to the Korean War. She served as an aircraft transport and helicopter carrier during the conflict, earning two battle stars for her service.
After the war, Makassar Strait continued to serve in various roles, including as a training ship and as a transport for military personnel and equipment. She was finally decommissioned on February 15, 1960, and sold for scrap in 1961.

US Navy ww2 USS Wyndham Bay (CVE-92)


USS Windham Bay ferrying F86 jets to Korea in the 1950s

US Navy ww2 USS Makin Island (CVE-93)


USS Makin Island underway near Leyte, November 1944
USS Makin Island (CVE-93) was named after the Battle of Makin, a raid by the United States Marine Corps against Japanese forces in the Pacific Theater of Operations during World War II.
Makin Island was commissioned on April 9, 1944, and served in the Pacific Theater of Operations during World War II. She participated in several major campaigns, including the Battle of Leyte Gulf and the Battle of Okinawa, where she provided air support for ground forces.
After the war, Makin Island was used to transport troops and equipment back to the United States as part of Operation Magic Carpet. She was decommissioned on June 27, 1946, and placed in reserve.
Makin Island was later recommissioned on September 1, 1950, in response to the Korean War. She served as an aircraft transport and helicopter carrier during the conflict, earning three battle stars for her service.
After the war, Makin Island continued to serve in various roles, including as a training ship and as a transport for military personnel and equipment. She was finally decommissioned on May 15, 1959, and sold for scrap in 1960.

US Navy ww2 USS Lunga Point (CVE-94)

USS_Lunga_Point_CVE-94_underway_in_the_Mindanao_Sea_on_3_January_1945
USS Lunga Point (CVE-94) was named after Lunga Point, a promontory on the island of Guadalcanal, which played a key role in the Guadalcanal campaign of 1942-1943.
Lunga Point was laid down on 15 December 1942 at the Kaiser Shipyards in Vancouver, Washington, and launched on 10 May 1943. She was commissioned on 10 November 1943, with Captain H. A. Guthrie in command.
After completing her shakedown cruise off the West Coast, Lunga Point was assigned to the Pacific Fleet and participated in operations against Japanese forces in the South Pacific. She provided air support for the invasion of the Marshall Islands in January 1944 and the invasion of the Mariana Islands in June 1944.

In December 1944, Lunga Point was part of a task group that attacked Japanese shipping in the Sulu Sea. During the attack, she was hit by a kamikaze, which caused significant damage to her flight deck and hangar deck. She was able to return to port for repairs and rejoined the fleet in time for the invasion of Okinawa in April 1945.
After the war, Lunga Point was used to transport American troops back to the United States as part of the “Operation Magic Carpet” program. She was decommissioned in June 1946 and placed in reserve.
Lunga Point was reactivated during the Korean War and served as a transport for military equipment and personnel. She was decommissioned again in 1954 and placed in the Pacific Reserve Fleet. She was struck from the Navy List in 1959 and sold for scrap in 1961.

US Navy ww2 USS Bismarck Sea (CVE-95)


USS Bismarck Sea (CVE-95) was named after the Battle of the Bismarck Sea, which took place in March 1943 and resulted in a decisive Allied victory over Japanese naval forces in the South Pacific.
Bismarck Sea was laid down on 15 December 1942 at the Kaiser Shipyards in Vancouver, Washington, and launched on 17 April 1943. She was commissioned on 20 November 1943, with Captain J. W. Harris in command.
After completing her shakedown cruise off the West Coast, Bismarck Sea was assigned to the Pacific Fleet and participated in operations against Japanese forces in the South Pacific. She provided air support for the invasion of the Marshall Islands in January 1944 and the invasion of the Mariana Islands in June 1944.

On 21 February 1945, Bismarck Sea was hit by a kamikaze during the Battle of Iwo Jima. The attack caused a massive explosion that destroyed the ship, killing 318 of her crew and leaving 605 others wounded. The remaining crew members were rescued by nearby ships.
Bismarck Sea received three battle stars for her service during World War II. Her wreck site was discovered by a team of researchers in 2018, located off the coast of the Solomon Islands at a depth of approximately 4,300 meters.

US Navy ww2 USS Salamaua (CVE-96)


USS Salamaua (CVE-96) was named after the Battle of Salamaua, which took place during the New Guinea campaign of World War II.
Salamaua was laid down on 7 June 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 21 July 1944. She was commissioned on 15 January 1945, with Captain W. W. Kilpatrick in command.
After completing her shakedown cruise off the West Coast, Salamaua was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.
After the war, Salamaua was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being placed in reserve in 1946.
Salamaua was reactivated in 1951 and assigned to the Atlantic Fleet. She operated in the Mediterranean and the Caribbean, providing air support for fleet operations and participating in NATO exercises. In 1959, she was decommissioned and placed in reserve.
Salamaua was struck from the Navy List on 1 September 1959 and transferred to the Maritime Administration for disposal. She was sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in August 1960.

US Navy ww2 USS Hollandia (CVE-97)


USS Hollandia (CVE-97) was named after the Battle of Hollandia, which took place during the New Guinea campaign of World War II.
Hollandia was laid down on 22 May 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 28 June 1944. She was commissioned on 6 December 1944, with Captain J. M. Shoemaker in command.
After completing her shakedown cruise off the West Coast, Hollandia was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.
After the war, Hollandia was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being placed in reserve in 1946.
Hollandia was reactivated in 1951 and assigned to the Atlantic Fleet. She operated in the Mediterranean and the Caribbean, providing air support for fleet operations and participating in NATO exercises. In 1959, she was decommissioned and placed in reserve.
Hollandia was struck from the Navy List on 1 September 1959 and transferred to the Maritime Administration for disposal. She was sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in August 1960.

US Navy ww2 USS Kwajalein (CVE-98)


USS Kwajalein 28 June 1944
USS Kwajalein (CVE-98) was named after the Battle of Kwajalein, which took place during the Pacific campaign of World War II. Kwajalein was laid down on 23 May 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 11 July 1944. She was commissioned on 18 November 1944, with Captain J. H. Carson in command.
After completing her shakedown cruise off the West Coast, Kwajalein was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.

After the war, Kwajalein was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being placed in reserve in 1946.
Kwajalein was reactivated in 1951 and assigned to the Atlantic Fleet. She operated in the Mediterranean and the Caribbean, providing air support for fleet operations and participating in NATO exercises. In 1958, she was decommissioned and placed in reserve.
Kwajalein was struck from the Navy List on 1 March 1959 and transferred to the Maritime Administration for disposal. She was sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in July 1960.

US Navy ww2 USS Admiralty Islands (CVE-99)

USS Admiralty Islands
USS Admiralty Islands ferrying planes 31 Dec. 1944
USS Admiralty Islands (CVE-99) was named after the Admiralty Islands in the southwestern Pacific. Admiralty Islands was laid down on 15 June 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 30 August 1944. She was commissioned on 9 January 1945, with Captain M. C. Hines in command.
After completing her shakedown cruise off the West Coast, Admiralty Islands was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.

After the war, Admiralty Islands was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being placed in reserve in 1946.
Admiralty Islands was reactivated in 1951 and assigned to the Atlantic Fleet. She operated in the Mediterranean and the Caribbean, providing air support for fleet operations and participating in NATO exercises. In 1958, she was decommissioned and placed in reserve.
Admiralty Islands was struck from the Navy List on 1 March 1959 and transferred to the Maritime Administration for disposal. She was sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in July 1960.

US Navy ww2 USS Bougainville (CVE-100)


USS Bougainville (CVE-100) was named after the Battle of Bougainville, which took place during the Guadalcanal Campaign in 1943.
Bougainville was laid down on 15 August 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 21 October 1944. She was commissioned on 9 February 1945, with Captain J. M. Shoemaker in command.
After completing her shakedown cruise off the West Coast, Bougainville was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.

After the war, Bougainville was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being decommissioned on 30 June 1946.
Bougainville was transferred to the Maritime Administration for disposal on 1 July 1960 and sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in October 1960.

US Navy ww2 USS Matanikau (CVE-101)


USS Matanikau (CVE-101) was named after the Battle of the Matanikau, which took place during the Guadalcanal Campaign in 1942. Matanikau was laid down on 6 October 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 7 December 1944. She was commissioned on 27 March 1945, with Captain S. S. Lewis in command.
After completing her shakedown cruise off the West Coast, Matanikau was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.

After the war, Matanikau was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made several “Magic Carpet” voyages before being decommissioned on 30 June 1946.
Matanikau was transferred to the Maritime Administration for disposal on 1 July 1960 and sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in October 1960.

US Navy ww2 USS Attu (CVE-102)

USS_Attu_CVE-102_in_the_western_Pacific_after_passing_through_a_typhoon
USS Attu (CVE-102) was named after the Battle of Attu, which took place in the Aleutian Islands in May 1943. She was laid down on 21 November 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 25 January 1945. She was commissioned on 30 April 1945, with Captain A. C. Sherman in command. After completing her shakedown cruise off the West Coast, Attu was assigned to the Pacific Fleet and participated in the final stages of the war against Japan. She operated in Japanese waters and provided air support for the occupation of Japan until November 1945.
After the war, Attu was assigned to the “Magic Carpet” operation, which involved the transportation of American troops from overseas back to the United States. She made two “Magic Carpet” voyages before being decommissioned on 12 June 1946.
Attu was transferred to the Maritime Administration for disposal on 1 July 1960 and sold for scrap to the Nicolai Joffe Corporation of Beverly Hills, California, in October 1960.

US Navy ww2 USS Roi (CVE-103)


USS Roi was named after the Roi Atoll, one of the islands in the Kwajalein Atoll in the Marshall Islands.
She was laid down on 17 December 1944 at the Todd-Pacific Shipyards in Tacoma, Washington, and launched on 28 February 1945. She was commissioned on 25 June 1945, with Captain A. J. Malone in command.
After completing her shakedown cruise, Roi was assigned to the Pacific Fleet and participated in the occupation of Japan. She operated in Japanese waters until January 1946, when she was ordered to return to the United States.
Roi was decommissioned on 12 June 1946 and placed in reserve. She was struck from the Navy List on 1 March 1959 and sold for scrap in 1960.

US Navy ww2 USS Munda (CVE-104)

uss munda san francisco bay 1945
USS Munda (CVE-55) was a Casablanca-class escort carrier of the United States Navy during World War II. She was named after the Battle of Munda in the Solomon Islands, which took place in 1943.
The ship was laid down on 22 February 1943 at the Kaiser Shipyards in Vancouver, Washington, and launched on 28 April 1943. She was commissioned on 27 August 1943, with Captain E. J. McCarthy in command.
After completing her shakedown cruise off the California coast, Munda departed San Diego on 27 October 1943, bound for the South Pacific. She arrived at Nouméa, New Caledonia, on 17 November and began operating with Task Group 37.4, providing air cover for the invasion of the Gilbert Islands. She continued to provide air support for various operations in the Pacific theater throughout the war.
In addition to her service in the Pacific, Munda also participated in the invasion of southern France in August 1944, providing air cover for the amphibious landings.
After the war, Munda was decommissioned on 16 February 1946 and transferred to the Maritime Commission for disposal. She was struck from the Navy List on 12 March 1946 and sold for scrap to the Hugo Neu Corporation of New York City on 21 November 1946.

Cristóbal Colón (1896)

Cristóbal Colón (1896)

Spanish Armada (1894-1898): Armoured Cruiser

The Spanish armored cruiser Cristóbal Colón was a warship that was built for the Spanish Navy in the late 19th century. It was launched in 1896 and commissioned in 1897. The ship was part of a naval program that aimed to modernize the Spanish Navy and increase its ability to project power overseas. Cristobal Colon was heavily armored and armed with a variety of weapons, including guns, torpedoes, and mines. It was designed to be fast and maneuverable, with a top speed of around 20 knots.
During the Spanish-American War of 1898, Cristobal Colon was part of the Spanish fleet that attempted to break through the American blockade of Santiago de Cuba. In the ensuing battle, the ship engaged in a running fight with several American ships, including the battleship USS Oregon.

Despite its speed and armor, Cristobal Colon was eventually cornered and heavily damaged by the American ships. The ship’s captain, Emilio Diaz Moreu, chose to scuttle the ship rather than surrender it to the Americans. The crew abandoned the ship and swam to shore, where they were captured by American forces.
The wreck of Cristobal Colon was discovered in 2015 by a team of researchers led by the Cuban-American explorer Robert Ballard. The wreck is located off the coast of Cuba and is considered a protected cultural site. #spanishamericanwar #1898 #battleofsantiago #spanamwar #cristobalcolon #garibaldiclass #armoredcruisers

Among the best armored cruisers of her day

The Garibaldi class Italian armoured cruisers were among the best of their time, with a record construction for Italy of more than 10 ships (11 planned, one cancelled). They were primarily sold to Argentina (four), Japan (two), and saw service with Italy which had three, Varese, Guiseppe Garibaldi and Francesco Ferrucio (1901). Spain soon also considering the design, amidst rising tensions with the USA, notably to reinforce its Cuban fleet under admiral Cervera’s command.
These ships had been designed by chief engineer Edoardo Masdea, back in 1893, so it was still perfectly relevant in 1896. These cruisers combined rapidity, a powerful armament, and an overall satisfactory protection for their size. The last aknowleging delivery were the Japanese in 1904 a mere year before the construction of HMS Dreadnought and right on time for the Russo-Japanese war.

Cristobal Colon’s design

Cristobal Colon was, like the rest of the Garibaldi class, a very versatile ship able to hold its line in a fleet and play its standard cruisers roles as well, in between heavy cruisers and battleships. These ships were built quickly at a lower cost than most European shipyards becoming the first Italian major export success for such class of ship.
Naval architect Edoardo Masdea known improved much on the former Vettor Pisani-class, submitting to the admiralty a competely reworked design under directives of Minister of the Navy Benedetto Brin and in collaboration with Ansaldo Yard charged to built the first Argentinian ship (named Garibaldi). Speed was probably the most important improvement factor, notably to catch up with the latest battleship generation.

Compared to the Vettor Pisani, the new design was 1,000 tons heavyer to match nigh-impossibly stringent requirements, as the ship needed a far larger powerplant. So it was to combined a better armament and better protection for 20 knots. In the end, 40% of the total displacement went structural weight (not including armor), 15% to artillery, including ammunition 25% to the armor and 20% to the powerplant. The new cruiser was to have two twin gun turrets fore and aft of the superstructure with 8-in guns. However It ws revised, and in the case of Spain, the Italian solution was chosen, a twin 8-in aft, single 10-in forward.

Design of the class

Hull and general design

The hull was flush deck with a rounded stern and ram bow. The width/length ratio imposed by the machinery was more for agility than speed, but they were stable platforms and their superstructures not tall (the funnel were), almost completely symmetrical. The rudder was semi-compensated type to ease manoeuver.

Armour protection layout

Armor was of the Harvey-type, with case-hardened steel for high hardness. It was uniform up to the deck: The nickel-plated steel plating reached 150 mm (6 in) down to 80 mm (3.5 in) on both ends of the belt. The central battery was protected by 130 mm (5 in) sides and the armored deck had 38 mm (2 in) flat section, with a slight curvature to the sides. The main 8-in/10-in turrets were protected by 150 mm (6 in), and the 152mm/40 (6-in) were protected by 130 mm casemate shield. Underwater protection comprised a partial double bottom and heavy compartimentation.

Powerplant


Cristobal Colon was powered by two vertical triple expansion (TE), reciprocating engines, fed by twenty-four coal-fired small-tubes boilers. Suppliers depended of the yard, which was here like most ships, Ansaldo, Genoa. It seems she had 24 Niclausse boilers and developed circa 13,600 shp for 19.5 knots. This output was passed onto two shafts ended by three-bladed bronze propellers.
Her range was 4,400 nmi (8,100 km) at 10 kn (19 km/h).

Armament

St Bon 10 inch gun turret right elevation
The main armament was specific to Cristobal Colon as designed: To the demand of the Spanish admiralty in 1895, Cristobal Colon was fitted initially with two Pattern R guns 10-inch guns: One forward and one aft. However the Spanish admiralty claimed the ones proposed by Ansaldo, Cannone da 254/40 A 1893, a patented version of the British ones, were defective, and asked for a replacement to Vickers Elswick, as the EOC 10 inch 40 caliber. However since the ship was urgently needed, she was sent to Cuba before this was done, and only ended with either only the initial aft gun or nothing at all as most sources states. She also gained ten smokeless powder Armstrong 6-in guns mounted in the hull casemates five on each side, instead of the Ansaldo models cannone da 152/40.
Thus, Cristóbal Colón should have been equipped with two 254mm (10 inches) cannons that were never fitted, leaving instead a different arrangement with a twin 8-in gun aft and not gun forward, leaving an empty turret.

Secondary

She had ten single 152 mm/45 (6 in) guns – Standard Ansaldo Type, 1 rpm, mv 830 m/s (2,700 ft/s) range 19.4 km (12 mi) in casemate along the battery deck.
She also hand six single 120 mm (4.7 in) guns Modello 1893: 5-6 rpm, mv 2,215 fps (675 mps), 9,900 yards (9,050 m), in the castes bridges fore and aft and in hull’s recesses.

Tertiary

It was rather on the light side, but making in numbers what it lacked in punch or range with the following:
Ten single 57 mm (2.2 in) guns: Standard 2.2 pdr (QF 6-pounder) Hotchkiss: 25 rpm, mv 1,818 fps, 4,000 yards (3,700 m) range
Ten single 37 mm (1.5 in) guns: QF 1-pounder pom-pom (liquid cooled): ~300 rpm mv 1,800 ft/s, 4,500 yards (4,110 m) range
Two Maxim machine guns. The latter were designed to be carried ashore on boats and cover landing parties

Torpedo Tubes

Colon was completed like the rest of the class with four single 450 mm (17.7 in) torpedo tubes. Supposedly same as the Italian type, Whitehead 1893 model. Reloads unknown.


Spanish Cruiser Cristobal Colon, the only one sunk, during the Battle of Santiago de Cuba, 1898 Hispano-American war.

⚙ specifications

Displacement 6,840 t standard 7,400–7,700 t FL
Dimensions 108.8/111.73 oa x 18.9 x 7.32 m (366 ft 7 in x 62 x 24 ft)
Propulsion 2 shafts VTE, 8–24 Boilers 13,000–13,500 ihp (10,100 kW)
Speed 20 knots (37 km/h; 23 mph)
Range 5,500 nmi (10,200 km; 6,300 mi) at 10 knots (19 km/h; 12 mph)
Armament (2x 254mm), 10x 152mm, 6x 120mm, 10x 57 mm, 10x 37mm, 4x 450 mm TTs.
Armor Belt 70-150, CT 150, turrets 190, decks 100-150, barbettes 10-150 mm
Crew 555 total, 578 as flagship

Links/Sources

Books

Fraccaroli, Aldo (1970). Italian Warships of World War I. London: Ian Allan.
John Gardiner’s Conways all the world’s fighting ships 1860-1906, Italian section
Gardiner, Robert & Gray, Randal, eds. (1985). Conway’s All the World’s Fighting Ships: 1906–1921.
“Professional Notes–Italy”. Proceedings of the United States Naval Institute. NIP
Silverstone, Paul H. (1984). Directory of the World’s Capital Ships. New York: Hippocrene Books
Sondhaus, Lawrence (2001). Naval Warfare, 1815–1914. London: Routledge.
United States Office of Naval Intelligence, United States Navy (July 1901). “Steam Trials–Italy”. Government Printing Office
Nofi, Albert A. The Spanish–American War, 1898. Conshohocken, Pennsylvania:Combined Books, Inc., 1996.
El condestable Zaragoza. Crónica de la vida de un marino benidormense, 1998. R. Llorens Barber. Town Hall of Benidorm.

Links

https://www.spanamwar.com/colon.htm
https://www.ibiblio.org/hyperwar/OnlineLibrary/photos/sh-fornv/spain/spsh-ag/cr-colon.htm
http://www3.udg.edu/fcee/professors/gcoenders/Colon.htm
https://www.navypedia.org/ships/italy/it_cr_giuseppe_garibaldi.htm
https://wrecksite.eu/wreck.aspx?149160
http://www.navweaps.com/Weapons/WNBR_47-40_mk1.php
https://en.wikipedia.org/wiki/Spanish_cruiser_Crist%C3%B3bal_Col%C3%B
https://www.spanamwar.com/colon.htm
https://es.wikipedia.org/wiki/Emilio_D%C3%ADaz-Moreu

Models Kits

https://www.super-hobby.fr/products/Cristobal-Colon-Spanish-Navy-armored-cruiser.html

Spanish Navy Cristobal Colon’s short career

photo
Cristóbal Colón was built in Italy under the initial name Giuseppe Garibaldi (ii), second ship of class and name, laid down in 1895, launched by September 1896, and sold to Spain, then delivered at Genoa to a Spanish crew, and taken in hands on 16 May 1897 with a transfer ceremony. She was the Spanish Navy’s first true armored cruiser and her best cruiser so far. Due to the Spanish Ministryrejevting her planned main guns, she sailed without them in the hope to be able to fit some later. This was never done.

Impressed in the Spanish Navy’s 1st Squadron as tensions with the United States were degraded after the explosion and sinking of the USS Maine in Havana harbor on 15 February 1898, she was prepared for war. The squadron was at first concentrated at São Vicente, in Portugal owned Cape Verde Islands. She arrived in Cadiz for preparations and departed on 8 April, learning of the war breaking out while off São Vicente. She was at first sent in by neutral Portugal toi recoal, but due to international law she had to leave within 24 hours of the declaration of war.

Thus, Cristóbal Colón and the rest of Cervera’s squadron was underway by 29 April, heading for San Juan in Puerto Rico. They needed to recal mid-way and stopped in French Martinique, Lesser Antilles, on 10 May 1898. While the bulk of the fleet stayed in international waters, only two Spanish destroyers entered Fort-de-France to ask for coal, but France pushed its neutrality and refused to supply coal. Thus Cervera had to sail out on 12 May 1898, heading for Dutch Curaçao (Western Indies) expecting to meet a Spanish collier here.

Cervera arrived at Willemstad, on 14 May 1898. The approach to neutrality was different. Given the emergency context, the Dutch authorities only authorized Cervera to send the cruiser Infanta Maria Teresa and her sister ship Vizcaya, and to load only 600 long tons. The meagre coal stock as later distributed between his ships and on 15 May instead of San Juan, now under U.S.N blockade, he wanted to make it to the still free Santiago de Cuba, at the the southeastern tip of Cuba.

Santiago’s Blockade

He managed to arrive on 19 May. The admiral hoped to refit his ships before being trapped, and recoal as well. But he was caught still there when the American “flying squadron” arrived on 27 May 1898, initiating the blockade, a 37 days long affair.

Cristóbal Colón at the time was anchored in the entrance channel. This was on purpose to support Santiago’s shore batteries. On 28 May she was spotted and recoignised by a naval detachment of the American blockade fleet. Therefore, admiral Sampson was to attack her in priority, recoignised as the best asset in Cervera’s fleet. Little they knew she lacked her main guns at the time. At 14:00, 31 May, the battleships USS Iowa and USS Massachusetts as well as the cruiser USS New Orleans closed in and opened fire on Cristóbal Colón, also engaging the shore fortifications from 7,000 yards (6,400 m). Both the Spanish cruiser and coastal artillery answered. A cease fire was ordered at 14:10 to assess the damage, whereas the Spaniard went on firing sporadically until 15:00. As seen above, Cristóbal Colón only had her casemated guns, cabable of 19.4 km (12 mi), so twice the normal range. But accuracy was still poor, and no side many any impression.

The blockade went on and the US fleet returned for an occasional gunnery duel or bombardment of the harbor. Cristóbal Colón was partly stripped of her crew, which joined others forming an ad hoc Naval Brigade sent to fight the U.S. Army inland as they approached Santiago de Cuba. It is likely also her two Maxim maching guns were also landed and sent with her contingent.

Cervera’s “mad run”

By early July 1898, this threat to Santiago de Cuba inland was closer and Cervera, being pressured by the government to act, having for them enough time to prepare, was forced to try a run out in the open sea, which he decided on 1 July 1898, to start on 3 July 1898. In between the crew of Cristóbal Colón was recompleted as the Naval Brigade inland was dissolved for this operation. The entire day was spent preparing for action, but Vice Admiral Cervera chosed Infanta María Teresa as his flagship. He took the lead and chosed a bold approach, sacrificing his ship by drawing fire frm the blockade fleet, to enable others to escape in several directions. He setup a plan to attack the fastest American vessel at the time, which was the armored cruiser USS Brooklyn, while Cristóbal Colón and the rest would make for it westward in the open sea.

At about 08:45 hours this 3 July, his squadron arrived in a single column and Cristóbal Colón was third in line. She was behind the flagship Infanta María Teresa, her sister Vizcaya, and Almirante Oquendo (third of the class) behind Colon, as the destroyers Furor and Plutón also right behind her. Sampson’s squadron sighted them at 09:35 and general quartrers alarm was heard on all ships. The opposition comprised, in addition to Commodore Winfield Scott Schley’s “Flying Squadron”, Sampson’s armored cruiser USS New York, Schley’s armored cruiser USS Brooklyn, while their best core was comprised by the slower but hard-hitting USS Indiana, USS Massachusetts, USS Iowa, and USS Texas, to which USS Oregon, coming from Mare Island, California and only battleship defending the US West coast, was to be added, making 66 days run to Cuba. Both forces were united under command of Sampson. On his side, Cervera only hope was to allow his three cruisers to out-run the battleships, and himelf trying to retain the fleet as long as he could.

And thus the Battle of Santiago de Cuba began. Infanta María Teresa and Vizcaya soon engaged USS Brooklyn, and Cristóbal Colón as well as Almirante Oquendo, and the two destroyers speeding up westwards out on the open sea. USS Brooklyn turned away from Infanta María Teresa and eventually all four Spanish armored cruisers stayed in line, heading directly at the armed yacht USS Vixen.
Cervera managed as he hoped, to escape. Thus the US squadron started a “hot stern chase”, steaming along a mile to port, slightly behind and all guns blazing along the way. Cristóbal Colón managed to hit Iowa twice with her casemate guns. The battleship’s dispensary was destroyed and she was holed belowed the waterline, taking some flooding, but still firing. Outgunned, the Spaniards were hit by 12-in shells (or 10-in from Texas and the two cruisers) which were armor piercing, making untold damage, while the range was close enough for secondary guns on both side to rain down high explosive shells, destroying superstructures and ingiting fires.
The cruisers started to ground themselves before theirr magazines could explode and save their crews, Infanta María Teresa being first, ending 10:25 west of Santiago, Almirante Oquendo was beached a few hundred yards away at 10:30 and Vizcaya in turn at 11:06, making it ashore. Alfredo Villamil (Spanish inventor of the destroyer)’s Furor and Plutón were soon devastated and sank in turn. The whole squadron only comprised Cristóbal Colón, which found iself alone, but also the most resilient of the pack.

Cristóbal Colón’s lone hour race

Her captain thought he still could get away, but her uncared machinery failed to give her expected 19 kts top speed after all this time, but she proved her extraordinary resilience so far, hit by two 5 or 6 inch hits, and still maintaining 15 knots (28 km/h). Only USS Brooklyn (capable of 20 knots – she even reached 21.91 knots on Trials) still was maintaining her chase 10 km behind her. USS Vixen followed Brooklyn, and next was the USS New York also maintaining 20 knots and now closing. The rest of the line comprised USS Texas, Oregon also in forced heat (they still can maintain 15 kts).

A full hour passed, after which Cristóbal Colón burned all her “best coal” and had to carry on with inferior grade, coal, resulting in thicker smoke and lesser output. Mechanically, she started to loose speed, from 14 to 13 and soon 12 knots. Soon the whole hunt was about to end: At 12:20 USS Oregon managed to land a 13-inch (330-mm) astern of her, and sen more closer, while the two armored cruisers managed to straddled her with 8-inch (203-mm) rounds.

Slowly but surely as the speed went down they were about to find their mark. The Spanish cruiser could do little but reply with mostly innacurate fire. She was hit six times but when the distanced closed to 2,000 yards (1,830 m), Cristóbal Colón’s Captain Emilio Díaz-Moreu y Quintana decided there was no hope of winning this one. He decided to beach his cruiser at the mouth of the Turquino River, located 75 miles west of Santiago (and probably signalled it for the US fleet to cease fire).

Emilio Díaz-Moreu’s report:
Complying with the orders received, I left with the ship under my command, occupying the designated position, from the port of Santiago de Cuba, being both ahead of the Morrillo at 9:45 in the morning, opening fire against the Iowa, which was the ship nearest at the time of departure.
Five minutes later, the Brooklyn being the most advanced ship in the enemy line, I ordered the batteries to direct all fire on her and whatever possible against the Oregon, which was on the port wing and which was not attention could be devoted due to lack of guns hunting and retreat. This was done, firing 184 shots against said ship with the 15 cm cannons and 117 with the 12 cm battery, having the certainty of having hit the target with 10 percent of the shots.
– Of course I saw that neither the Brooklyn nor the Oregon, which hunted me down, could catch up with me and the first one stayed faster than the second one and I continued close to the coast heading towards Cabo Cruz.- At 1 in the afternoon the boiler pressure began to drop, reducing the revolutions from 85 to 80, beginning, therefore, to win over the Oregon, which shortly after opened fire on the ship with its large-caliber hunting guns, which I could only answer with shots from the number 2 gun of the battery, winking to that effect as necessary, even if this shortened the distance.
– In view of this and given the absolute certainty of being captured by the enemy, according to Your Excellency, as it would not be advisable to distract any Chief and Officer from their destinations, given the structure and layout hatches, which represented a much-needed loss of time and with the aim of taking advantage of the opportunity, if it presented itself, to fire, and in order to avoid being captured, we decided to run aground and lose the ship and not sterilely sacrifice the lives of those who had fought with the heroic courage, discipline and seriousness that Your Excellency has been able to appreciate for yourself, and as a consequence of the agreement, we headed towards the Tarquino River, on whose beach I ran aground, with speed of 13 miles, at 2 o’clock in the afternoon. Once the ship was beached and the Chiefs and Officers assembled, they all expressed their agreement to what had been done, understanding that if they continued, even for only a few moments, they were in imminent danger of falling into the hands of the enemy and being a war trophy that was necessary at all costs to avoid.

Shortly afterwards we became prisoners of war on the Brooklyn, the Commander of which appeared on board shortly after. During the combat I had one dead and twenty-five wounded, whose list accompanied Your Excellency as a result of the enemy projectiles, which although they hit us in large numbers, did not cause damage to the protected part of the ship.

At 13:15 hours he ordered to open valves to scuttle his ship, preventing capture. The cruiser started sinking while sailors jumped out and tried to swim ashore. What they failed to realize was that they had been tracked by Cuban insurgents along the coast, which made all the way to this area, and started to shoot from the vegetation cover. Understanding what was happening, Sampson ordered to signal the insurgents to cease fire (apparently some that made it to the beach were butchered with machetes). He also ordered boats to be sent and rescued survivors still on the ship. Captain Díaz-Moreu survived the battle and was taken in custody until the end of the war.


She ship capsized, photo made by the USS Vulcan salvage team afterwards.

A colorized photo of Allison.V Armour in 1899 of the wreck being inspected.

That night a USN salvage team from USS Vulcan reported to Sampson that the Cristóbal Colón was worth salvaging. They managed to have her towed away, only to realize she had been scuttled and the flooding caused her so quickly capsizing and sink. The wreck is now part of the Naval Battle Underwater Park of Santiago de Cuba, open to divers.

Site News: The Royal New Zealand Navy from the cold war to this day.


The RNZN, or Royal New Zealand Navy. Although diminished aft WW2, the Kiwi navy operated two Dido-class and soon a completely modified one, HMNZS Royalist, a good exemple of a modernized Dido in the cold war; But the navy also operated frigates, corvettes, minesweepers and patrols crafts to monitor an extensive EEZ. In this post the history, organization, operations, modernization and a brief look at the modern NZ Navy, now concerned as Australia with the rapid rise and ambitions of the Chinese PLAN. #RNZN #newzealandnavy #kiwinavy #waitangiday #newzealand #coldwar #hmnzsroyalist


Curtiss SBC Helldiver (1933)

Curtiss SBC Helldiver (1933)

USN aviation USN Carrier Dive Bomber 1935-1940 (257 built)

Curtiss biplane dive bomber

The Curtiss SBC Helldiver was a two-seat scout/dive bomber from Curtiss-Wright and the last military biplane of the USN, introduced from 1937. Although a biplane, it was a modern and very strudy, reliable model seeing service on USS Saratoga, Yorktown and Enterprise in 1938-1940 before being gradually replaced in 1940-41 by the SBD Dauntless. Some models saw service in the French Armée de l’Air and RAF in 1940-42, the latter used as the Cleveland Mark I. The SBC-4 was used as late as 1943 by the USMC and it was only retired in 1945, used as a trainer.

Design development of the first “Helldiver”

Controversy in the USN’s Bureau of Aeronautics (BuAer) in 1930 raged on for what concerned two-seat fighter planes over the monoplane configuration AND retractable undercarriage. In 1931, the Navy issued Design Specification No.113, a requirement for a high-performance fighter with fixed undercarriage and the Wright R-1510 engine, alternative to the Pratt & Whitney’s R-1535. No less than seven companies answered with a proposal. Eventually two were retained: Douglas, presenting with its XFD-1, and Chance Vought, with its XF3U-1. Both were two-seat biplanes, so in doubt the Navy asked Curtiss to provide another prototype of a monoplane, technically more advanced.

On 30 June 1932, BuAer norified Curtiss its latter proposal was accepted. Soon, a contract was signed to design a two-seat monoplane. But Curtiss model had both a parasol wing AND retractable undercarriage, powered by the 625 hp Wright R-1510-92, a 14 cylinder 2-row radial engine driving a two-blade metal propeller. The prototype designed XF12C-1 was soon prepared for its first flight.

Design Development

XF12C-1 (Curtiss M73)


Curtiss XF12C-1 prototype
So the Curtiss parasol model was very modern for the time, with an enclosed glassed-cockpit, all-metal with only the wings, rudder, elevators and flaps fabric covered.
It was initially given the Wright R-1510-92 engine but soon that was proven a bad match, the model was anemic. Thus, the company soon tested and proposed to the Navy the 775 hp (578 kW) Wright R-1670, 14-cylinder doubled row radial, but again the latter proved unsatisfactory. Both were essentially prototypes engines and suffered from reliability issues, so much so that eventually they never went into production.

The more trusted 700 hp (522 kW) Wright R-1820-80 9-cylinder double row was eventually installed and the prototype XF12C-1 first flew in 1933. It was design for aircraft carrier use and thus, had its parasol wing folding back along a central hub. It also had an exposed tail hook to land. After July 1933 more flights and tests took place. By September 1934, the model was to be used as a drive bomber, but the parasol wing proved ill-suited for the task. The air resistance was just too much. Since cantilever monoplanes were still science fiction at the time, Curtiss proposed to remodel the prototype as a biplane. At least the two planes would be smaller in size and support each others in a dive.

XS4C-1 (M73)

The Curtiss M73 was however not complete redesign of the original prototype as a biplane, but just rejected both as a dive bomber and fighter, and instead on 7 December 1933 it was redesignated as the XS4C-1, as cout, re-engined with a 700 hp (522 kW) Wright R-1820-80 radial and two-blade propeller for more endurance. It became a scout aircraft but still capable to carry a 500-pound (227-kilogram) bomb.

XFBC-1 (M73)

As bomb rack tests were concluded in a satisfactory manner in January 1934, the designation scout bomber (SB) was introduced and the M73 was redesignated XSBC-1. From early 1934 the new monoplane multiplied flight tests but also resume dive-bombing tests. On 14 June 1934 the prototype crashed, unsurprisingly due to to wing failure close to New York’s Curtiss plant. Completely destroyed, the root cause of the failure was reported bu Curtiss, proving one again that the biplane solution was preferrable.

XSBC-2 (M77)


Thus, Curtiss redrawn the prototype with staggered wings and mad this paper proposal to the Navy. Curtiss-Wright ensured that if the new model would have no folding wings at least it would have a shorter span and leading edge slots with only the lower wing given full span flaps. Again, it was an all-metal model with control surfaces still covered in fabric. It had the 14-cylinder radial Wright XR-1510-12 rated for 700 hp (522 kW). And it was mater this time to a constant speed Curtiss Electric three-blade propeller.
This new prototype also had an enlarged canopy and for better stability when diving, an enlarged vertical fin and rudder. It also kept the same retractable tail hook and undercarriage of the previous model 73. The Curtiss model 77, called by the Navy XSBC-2, started competitive tests against the Great Lakes Aircraft’s XB2G-1 and the Grumman XSBF-1, but the XSBC-2 won and earned a contract, signed by the Navy in April 1935. The definitive protype XSBC-2 made its first flight on 9 December 1935.

As part of the explanation of how the USN was fielding dive bomber biplanes in 1941, two years had been lost by the insistence of the navy staff to keep a monoplane configuration, with changing requirements and priorities, from fighter to scout, scout-bomber and dive bomber. Still, after these two years, Curtiss has been working on th biplane and knew it was going to win the new competition.

XSBC-3 (M77)


The Wright XR-1510-12 engine however was now the faulty part of the design, untested, it proved unreliable. Tests were plagued by issues unti Curtiss made a re-engined proposal, which was accepted. By March 1936, the 14-cyl. twin-row Pratt & Whitney R-1535-82 (rate for 700 hp (522 kW)) with the same three-blade propeller became the XSBC-3. This time, all tests were successful and spotless. The Navy, eager to have its dive bomber after nearly three years of waiting, immediately planed an order.

Production Models

SBC-3 (Model 77A)


Curtiss SBC-3 from scouting squadron 3 visiting NRAB Oakland in 1938
And thus, the XCBC-3 became the SBC-3 in production, and again, differed from the prototype by its new engine: The 83 ordered in August 1936 were delivered with the much powerful (825 hp/615 kW) Pratt & Whitney R-1535-94, also a 14-cyl, 2-row model. The SBC-3 started to be delivered from 17 July 1937.
Something which as until then almost an afterthought was its armament: Two MGs. One right-side forward-firing 0.30-caliber (7.62 mm) machine gun (doubling its role as a fighter) and for close defence and a tail gun on a flexible mount in the rear cosckpit, under the cover of the turtleback.

Also technology went on in between and the best way to deliver a bomb was not firmly established as a displacement swing placed under the belly, centerline to carry and deliver under the propeller’s arc a 500-lb (227-kg) bomb or 45-U.S.-gallon (170-liter) fuel tank. The 83 SBC-3 were not followed as Curtiss was already proposing a better version, which had to be tested first:

XSBC-4 (Model 77B)


Already on the production line, the 73th SBC-3 was held to be re-engined with the much more powerful Wright R-1820-22 a 9-cylinder single-row but which developed 950-hp (708 kW). It was driving a three-blade Hamilton Standard propeller. The modified model was redesignated XSBC-4 and its forward light MG was replaced by the more impressive 0.5-cal. (12.7-mm) Browning M1920 on the right side. It was possible thanks to the shorter engine. It retained the same rear 0.3-cal. Brownng M1919A4 in the rear cockpit on an improved flexible mount, and the better performances allowed the SBC to now carry the largest aviation ordnance on disposal, a 1,000-lb (454-kg) bomb, with its swing fork redesigned and made larger. A second SBC-3 was also designated XSBC-4 was kept for further tests during the SBC-4 production as Curtiss was confident the Navy would accept the upgrade.

SBC-4 (M77B)


A formation of SBC-4s from NRAB New York (Naval reserve) in formation 1940

The final evolution of the SBC was also the largest production batch: 124 production were ordered on 5 January 1938, deliveries starting in March 1939, until April 1941. In between, the war has started and Curtiss, examined by a French and later a British commission, were in turn ordered, porting the final count when production ceased in early 1941 to 257 machines. With a nearly 1000-hp engine and 1000-Ibs bomb, the rugged biplane (made for carrier use) still was one of the world’s best dive bomber still in 1940.

Indeed, the Vought Vindicator was the alternative model also introduced on US Aicraft Carrier, and albeit of the same generation, the Vought model was produced earlier and has a monoplane cantilever configuration. In total from 1933 to 1938, development of this model took a staggering six years. By that interval, aeronautocal tech went through many iterations and innovations, as tactics changed along the way. Only it’s good overall performances made the Curtiss M77 a fine design, close in general philosophy to the Grumman FF and F2F, F3F fighters.

Final design


The SBC in its early like production version was a modern, all-metal and two-seat scout-bomber biplane. The monoplane prototype had “Y”-type interplane struts, the biplane had “I” Type. Since it came in production relatively late, it became de facto the last combat biplane purchased by the Navy. The two crewmen were the forward seating pilot and rearwards seated radio operator which doubled as gunner, both protected in tandem cockpits, with sliding canopies. The fuselage was made of steel frames, with stressed aluminium skin sheating.

There was a turtledeck behind the rear cockpit which could be folded down, allowing the gunner to raise and fire his machine gun. In noormal conditions it was raised up to reduce drag and improve stability. The wings, rudder, elevators and flaps were all fabric covered as customary at the time. The main landing gear could be fully retracted, into wheel wells designed by Grumman, both located in the fuselage forward of the lower wing. The tail wheel could also be retracted into the fuselage. So apart the biplane configuration, this was really a modern aicraft by all measures.



Forward and aft sections of the cockpit (NARA/ONI)

The pros and cons of the biplane formula were well known: Lof of lifting capacity, superior agility, lower landing speed. Its disadvantages were a lower structural integrity for high speeds, and limits in dive speeds, as well as reduced visibility (at least in the low-mounted variant, as the prototype has a parasol wing, for excellent visibility). Overall, the biplane configuration and speed limitations did not hampered much its use as diver bomber.

Engines:

Pratt & Whitney R-1535-94 (SBC-3)
Also called the “Twin Wasp Junior”, this engine as derived from a serie starting with the model 11 developing 750 ch (559 kW) in 1932. The model 94 825 ch (615 kW), and the configuration was of 14 cylinder in a double row radial configuration of two seven(cylinder rows, interleaved for better air cooling of the rear serie. Its capacity was 25,2 L with a 131,8 mm cylinder course and weighting 493 kg.

Wright R-1820-22 (SBC-4)
The famous “Cyclone” serie became a world famous engine in the early 1930s, also licenced by Hispano-Suiza in France, Lycoming Canada, and Shvetsov in USSR. This model was famously used by the Douglas DC-1, DC-2, DC-3, DC-5, Boeing B-17 Flying Fortress, Curtiss P-36 Hawk, GM FM-2 Wildcat, Douglas SBD Dauntless. The early R-1820-1 developed 575 hp (429 kW) and the final R-1820-G205A developed 1,200 hp (890 kW). The model 22 was an early model which developed 950 hp (710 kW).

Armament:

As describes above, the SBC-3 was given two light M1919 Browning machine guns: One on the right side, synchronized with the propeller as it fired forward, and the second on a flexible mount aft, manned by the rear gunner/radio/navigator. The bomb load was a single 500-lb (227-kg) bomb alternative to a 45-U.S. gallon (170-liter) fuel tank.
The SBC-4 was more powerful and allowed the replacement of the Browning 0.3 cal. LMG by a Browning M1920 HMG or 0.50-caliber (12.7-mm). It was forward of the pilot, firing through a recess but it’s unclear if a jamming could be resolved by the pilot underway. The range and ammunition impact was several fold greater and increased the chances of the Helldiver to really cause havoc on lightly-built Japanese aircraft. No change for the rear gunner, but the bomb load, thanks to the extra output, could be double, with a 1000 Ibs (454 kg.) bomb.

⚒ Specifications SBC-3 1938

Dimensions: L 28 ft x Wsp 34 ft x H 10 ft 5 in (8.574 x 10.36 x 3.18 m)
Wing area 317 sq ft (29.5 m2)
Airfield NACA 2212
Weight, empty 4,552 lb (2,065 kg)
Weight, gross 7,080 lb (3,211 kg)
Propulsion Wright R-1820-34 radial engine, 850 hp (630 kW)
Propeller 3-bladed constant-speed propeller
Speed, max. 234 mph (377 km/h, 203 kn) at 15,200 ft (4,600 m)
Speed, cruise 175 mph (282 km/h, 152 kn)
Ceiling 24,000 ft (7,300 m)
Climb Rate 1,630 ft/min (8.3 m/s)
Range 405 mi (652 km, 352 nmi)
Wing load 28.5 lb/sq ft (139 kg/m2)
Power/mass 0.282 kW/kg (0.172 hp/lb)
Armament: MGs 2 × 0.30 in (8 mm) Browning M1919 (? rounds)
Armament: Bombs 1 × 500 lb (227 kg) bomb/fuel tank
Payload: 1 × 58 US gal drop tank
Crew: 2: Pilot, gunner/navigator

The Curtiss SBC in Action & Operators

United States Navy Use


Nice color photo of a freshly arrived SBC-3 aboard an unknown carrier, yet to identify. (see the sources below)
The first SBC-3s arrived on 17 July 1937, scheduled for Scouting Squadron Five (VS-5) aboard USS Yorktown (CV-5) to start carrier qualifications. However, was still not commissioned until 30 September 1937 and had to perform her sea trials first. Meanwhile the planes trained on land. On 10 December 1937 at last, five months beyond schedule, VS-5 landed on Yorktown and was active on the carrier until replacement by Douglas SBD-3s Dauntles in 1940.

Various models a NAS Miami in 1942, with several SBCs in the background
Various models a NAS Miami in 1942, with several SBCs in the background

By June 1938, 3 out of 5 scouting squadrons on carriers ahd the new SBC-3s the remainder having to make due with the Vought SBU-1 Corsair (1935), the other “last USN biplane”. This when the war broke out in September 1939, the USN operated the Helldiver on USS Enterprise (CV-6), with VF-6 (One) and VS-6 (20 Helldivers), USS Saratoga (CV-3) had Bombing Squadron Three (VB-3) with a single SBC-3 while VF-3 had an SBC-3 and VS-3 had 21 Helldivers. There was also the veteran, USS Yorktown (CV-5) with VS-5 equipped with ten SBC-3s.
Based on the 5 January 1938 contract for 58 SBC-4s other deliveries were due tha year, whereas 31 more were ordered on 27 July 1938 and 35 aircraft on 13 August 1938 for 124 total.
The SBC-4 made its debut with VS-2 on USS Lexington (CV-2), the only one not equipped with the Helldiver. The SBC-4 replaced the Vought SBU-1 there and by 26 June 1939, VS-2 reached it max 21 aircraft provision. They were replaced after two years by the Douglas SBD-2/3 Dauntless.

SBC-3 Helldiver from VS-3
SBC-3 Helldiver from VS-3 (USS Saratoga) in flight, 1939

However as raising contracts enabling by the start of the war in Europe saw the remaining SBC-4s reassigned to Naval Reserve Air Bases, enabling reserve Navy and Marine airmen to maintain their proficiency on more modrn models.
By June 1940, there were 11 NRABs equipped with the SBC-4s:
NRAB Anacostia (3 SBC-4s to VS-6R and VMS-3R)
NRAB Boston (3 SBC-4s to VS-1R, VS-2R and VMS-1R)
NRAB Detroit, Michigan (3 SBC-4s to VS-8R and VMS-5R)
NRAB Glenview (4 SBC-4s to VS-9R)
NRAB Kansas City (4 SBC-4s to VS-12R and VMS-10R)
NRAB Long Beach (SBC-4s to VS-13R, VS-14R and VMS-7R)
NRAB Minneapolis (3 SBC-4s to VS-10R and VMS-6R)
NRAB New York (4 SBC-4s to VS-3R, VS-4R and VMS-2R)
NRAB Oakland (4 SBC-4s to VS-15R and VMS-8R)
NRAB Seattle (4 SBC-4s to VS-16R and VMS-9R)
NRAB St. Louis (3 SBC-4s assigned to VS-11R)
The SBC-3s were in turn replaced by SBD Dauntless and by 7 December 1941, in total 69 SBC-3s and 118 SBC-4s served with the USN/USMC between Naval Air Stations, Naval Reserve ABs, and the Naval Aircraft Factory in Philadelphia. NAS Miami in Florida had the more of those, usable for intermediate and dive bombing training until 1943.

When the attack on Pearl Harbor commenced in December 1941, SBC were deployed at NAF Philadelphia (XSBC-1 proto and 1 SBC-3), NAS Corpus Christi (34 SBC-4s), NAS Miami (55 SBC-3s) NAS Norfolk (4 SBC-3s, 10 SBC-4s), NAS San Diego (9 SBC-3s, 11 SBC-4s), and the Naval Mission in Lima, Peru, trying to sell it locally, with a single SBC-4 in demonstrations.

Surprisingly enough USS Hornet (CV-8) just completed was to be equipped with almost 40 Helldivers:
-Bombing Squadron Eight (VB-8) with 19 SBC-4s,
-Scouting Squadron Eight (VS-8) with 20 SBC-4s
Se actually made her sea trials in the Atlantic with her two SBC-4s squadron until sailing to San Diego via Panama in March 1942. In California, her two squadrons were replaced by SBD-3 Dauntless. She was the last US Carrier to operate the SBC.
The second French order in mid-1940 meant 40 SBC-4s, built between February and May 1941 were to be shipped overseas with a 126-U.S. gallon (477-liter) self-sealing fuel tank and were kept after the fall of France, the last being delivered in May 1941.
By 1944, the SBC-3 was stricken from the inventory, but still, the 12 SBC-4s from NAS Jacksonville had to wait until 31 October 1944 for their retirement. The very last of their kind. No USN SBC saw action. There were none at Pearl Habror.

USMC use


Model of the VMO-151 in 1941
The US Marines Corps soon obtained ex-US models from the carriers, when replaced by the Dauntless.
The Marines had their first SBC-3 in 1938 for evaluation, assigned to Marine Fighter Squadron Two (VMF-2, later VMF-211 by July 1941) based in NAS San Diego, and sent to the Battle Fleet Pool in June 1939. In January 1940 there were four SBC-4s at Marine Corps Air Station (MCAS) Quantico. One more was sent to VMF-1 and the XSBC-4 prototype was sent for testings to Marine Utility Squadron One (VMJ-1, later VMJ-152). The other two were in NAS San Diego, VMF-2 and VMJ-2 (VMJ-252).

At the time of the Pearl Harbor attack, the USMC had 23 SBC-4s in all, 12 in Marine observation squadrons at MCAS Quantico (the sole 1 XSBC-4 and 5 SBC-4s), NAS San Diego (5 SBC-4s) and MCAS Quantico (12 SBC-4s). VMO-151 was soon transferred to Tafuna (now Pago Pago) and Tutuila in Samoa, by 9 May 1942. This unit became Marine Scout Bombing Squadron (VMSB) 151 from 15 September 1942. VMO-155 was based in American Samoa on 1 October 1942 and was reinfoced by ten more SBC-4s and a single Grumman J2F-5 Goose. Personal and planes were sent to Guadalcanal afterwards.
By December 1942, VMSB-151 saw its complement replaced by the SBD Dauntless. By June 1943, it was reequipped with SBD-4s and moved to Uvea Island, Wallis.
There was a single SBC-4 at American Samoa (VMSB-151) on 1 June 1943. The Japanese never went there and its fate is uncertain.

French Aeronavale


In September 1939 both Britain and France were in dire need for aircraft, knowing the size of the Luftwaffe. By early 1940, the French government went to Curtiss-Wright and ordered 90 SBC-4s. To speed thnings up, on 6 June 1940 Franklin D. Roosevelt 50 from U.S. Navy stocks at the Naval Reserve to the Curtiss-Wright factory in Buffalo (New York) for a refurbishment to French standards. Markings, instruments, equipment were converted to metric and French, and French 7.7-millimeter (0.303-caliber) Darne machine guns replaced the original Brownings. it was completed by French camouflage and roundels as well as aeronavale markings. They were to delivered to RCAF Station Dartmouth in Nova Scotia (Canada) in order to be loaded onto the French aircraft carrier Béarn.

However in between, neutrality acts from U.S. Congress imposed for arms trade with belligerents a “cash-and-carry” system imposing transport by them using their own means. In short, in order to have them delovered, the planes flew to the frontier and had to be towed across the border. The 50 aircraft freshly converted made a trip from Buffalo, to Houlton Airport in Maine (via Burlington, Vermont and Augusta). The Houlton Airport was just at the Canada–US border. Local farmers were requisitioned with their tractors to tow the planes into New Brunswick. The Canadians closed next the highway in order to each towed SBC to fly off gfrom there to RCAF Station Dartmouth and be re-routed next.

The 50 made their ways over time to Dartmouth but one crashed due to bad weather, the remaining 49 flew next to Nova Scotia, waiting for the Béarn and light cruiser Jeanne d’Arc. The loading commenced, but since Béarn’s hangar was limited, only 44 could be carried aboard. She indeed also already had 25 Stinson Model HW-75s, 17 Curtiss H75-A1s (P-36) and even 6 Brewster F2A-2 of the Belgian Air Force already stacked on her deck. She even had 14 crated Stinson and Curtiss H75s.

The carrier sailed from Halifax on 16 June 1940 for Brest, but underway two days later they learned Brest was in German hands. Both ships were ordered instead to Fort-de-France in Martinique (French West Indies), arriving on 27 June. There, they knew French had surrendered to the Germans since five days. Then a purgatory commenced. The SBC-4s were unloaded, rolled to a field at Pointe des Sables, stored out in the open in tropical conditions. They degraded quite quickly until not being airworthy anymore and being scrapped later when the island fell to Free France. These 49 planes as well as the Stinsons, Curtiss H75 and Buffaloes were all lost in these conditions, never firing a shot. The island was under close watch by the US Navy, preventing any move back to France, which later amounted to a full-on blockade.

Royal Air Force


Five of the French aircraft left at Halifax returned to RCAF Station Dartmouth. By August 1940, the Royal Air Force acquired these, renamed “Cleveland Mk. I”. They went aboard HMS Furious which delivered them. Refurbished again at RAF Burtonwood in Lancashire they were sent to RAF Little Rissington in Gloucestershire and used by No. 24 (Communications) Squadron at RAF Hendon. They were in fact never used but as ground trainers after perhaps a few flights.

Legacy
As seen above, Curtiss tried to sell them to Peru also, but no deal was made. Unfortunately, noe survived to this day apparently. The discarded models in the US were scrapped. As for those *still rotting* in Martinique there is practically nothing left that was not taken long ago which could be a base for a restoration. Financing a reconstruciton would be tough also, as the model had no really active service but the few of the USMC in Samoa and is certainly “forgotten” today, especialy compared to the second one.

Gallery

Illustrations


XF12C-1 Prototype BuAer 9225, NAS Anacostia, ca1933

SBC-3, VC-5, USS Enterprise, 1938

SBC-4, 1st Marine Airwing Command, Quantico 1940.

SBC-4, Air Group Commander, USS Enterprise (CV-6) 1940

SBC-4 of the USMC, VBM-155 Samoa island, 1943, last operational model in operations

French SBC-4, Béarn, Martinique fall 1940

British RAF Cleveland I, 1942

Photos













Read More

Books

Angelucci, Enzo. The American Fighter. New York: Orion Books 1987.
Bowers, Peter M. Curtiss Aircraft, 1907–1947. London: Putnam & Company, 1979.
Doll, Thomas E. SBC Helldiver in Action, Aircraft Number 151. Carrollton, Texas: Squadron/Signal Publications, Inc., 1995.
Francillon, René J. McDonnell Douglas Aircraft since 1920, Volume I. Annapolis, Maryland: Naval Institute Press, 1988.
Gunston, Bill. World Encyclopaedia of Aero Engines. Newbury Park, California: Haynes North America, 1998.
Halley, James J. The Squadrons of the Royal Air Force & Commonwealth 1918–1988. Tonbridge, Kent, England: Air Britain (Historians) Ltd., 1900.
Jane, Fred T. Jane’s All The World’s Aircraft, 1945/6. New York: Arco Publishing Company, 1946.
Johnson, E.R. United States Naval Aviation 1919–1941. Jefferson, North Carolina: McFarland & Company, Inc, 2011.
Larkins, William T. U.S. Navy Aircraft 1921–1941; U.S. Marine Corps Aircraft 1914–1959. New York: Orion Books, 1959 and 1961.
Morareau, Lucien (September 1998). “Les oubliés des Antilles”. Avions: Toute l’aéronautique et son histoire (in French) (66)
Moran, Gerrard P. The CORSAIR and other AEROPLANES VOUGHT 1917–1977. Terre Haute, Indiana: Aviation Heritage Books, 1991.
Naval Historical Center, United States Naval Aviation 1910–1995. Washington, D.C.: U.S. Government Printing Office, 1997.
Sherrod, Robert, History of Marine Corps Aviation in World War II. San Rafael, California: Presidio Press, 1952.
Swanborough, Gordon and Peter M. Bowers. United States Navy Aircraft since 1911. London: Putnam, 1976.
Taylor, John W.R. Jane’s American Fighting Aircraft of the 20th Century. New York: Mallard Press, 1991.
Thetford, Owen. Aircraft of the Royal Air Force Since 1918. London: Putnam & Company, 1979.
Wagner, Ray. American Combat Planes of the 20th Century. Reno, Nevada: Jack Bacon & Company, 2004.

Links

On pacificeagles.net/
On avionslegendaires.net/
On militaryfactory.com/
on airwar.ru/
on jmodels.net/
On silverhawkauthor.com/
On aircraftresourcecenter.com
on aviastar.org/

Extra pics:
Prototypes photos
On airandspace.si.edu, colored
curtiss-sbc-4-helldiver-red-crossed/
On aerocorner.com/
more color on inchhighguy.wordpress.com
On commons.wikimedia.org/

Model Kits


The Matchbox kit, that i made many, many years ago (long gone) at the time, produced in colored grapes, grey, yellow and blue.
Surprisingly despite its complete absence of operational service, the French SBC-4 were covered by Heller to 1/72 Here
General query on scalemates
daviddoylebooks.com/ SBCs USMC VM151
https://finescale.com/product-info/kit-reviews/1998/01/classic-airframes-1-48-scale-curtiss-sbc-4-helldiver

Curtiss SBC-4 Helldiver

Aircraft Carrier Giuseppe Garibaldi (1983)

Giuseppe Garibaldi, 1st Italian STOVL carrier

Marina Militare Built 1981-85 currently in service

Italy Unification Day !
Giuseppe Garibaldi is one of the two current Italian aircraft carriers, and the first “through-deck” aviation ship ever built for the Italian Navy, first to operate fixed-wing aircraft (Aquila was never completed and Miraglia only operated floatplanes). She is equipped with short take-off and vertical landing (STOVL) which limited the aircraft types she could carry, but also carried all sorts of helicopters usable for assault missions. Giuseppe Garibaldi saw combat air operations off Somalia, Kosovo, Afghanistan and Libya.

Genesis of the Design


Initial Fincantiery project in 1978 More
The program for such new ship originated into the need in 1970 already to plan the replacement of the two Doria class Helicopter cruisers (1962) of which Duilio was intended to act as training ship for Livorno Academy cadets, replacing San Giorgio.
Construction was planned in the Naval Law of 1975, and the previous yer, the Navy had submitted to the Italian industry a project prposal for the construction of an all-deck naval unit. The initial project included a flat flight deck typical of helicopter carrier. Italcantieri won the contest over a project from Breda. After another year of working out the design, the Marina Militare naval staff eventually ordered it on 21 November 1977. The contract with Italcantieri stipulated to start work on 20 February 1978.
The choice conformed in 1979 its through-deck appearance, instead of a hybrid cruiser as Veneto and the Dorias, enabling more spots for anti-submarine warfare.

1978 Fincantieri project
1978 Fincantieri project
1978 Fincantieri project
1978 Fincantieri project

It was believed a continuous deck would enable a larger group of anti-submarine helicopters indeed. Nothing was precised about STOVL aicraft at this stage, due to an ancient naval law (see later). In addition of these fonctions and those of a cruiser, she had to combine command and control capabilities, in order to lead a an offshore operational group and coordinate a task force, placing its resources at the fleet disposal and of external ships (for a NATO oriented closer cooperation).

Indeed, the first Italian aircraft carrier was originally limited in its capabilities by a law dating from 1923, preventing the Italian Navy from operating combat aircraft from ships. When this law was changed in 1992, sixteen AV-8B+ were purchased. The design envisaged VSTOL aircraft operations, since it ultimately included a ski-jump ramp forward.

Construction


Launch in 1984

The construction of the unit took place in the Monfalcone factories. The cutting of the first sheet took place on 28 April 1980 and on 9 September of the same year construction of the first block began. On 26 March 1981 the first block was completed at Monfalcone shipyard. During construction of the deck it was decided to adopt a ski-jump not envisaged in the planning phase as planning the future adoption of aircraft.
On January 31, 1983, the assembly of the last block on the slipway was completed. By April 19, construction of the superstructure was complete. At last she was launched on 4 June 1983. The ceremony was attended by Prime Minister Amintore Fanfani, defense Minister Lelio Lagorio, who gave the inaugural speech. She was christened by Mrs. Flavia Donata Solvetti Garibaldi, wife of the last descendant of the namesake hero of the unification.

In drydock completion at Montfalcone
In drydock completion at Montfalcone

The ship started her initial sea trials on 3 December 1984 and she was eventually was delivered on 30 September 1985, the largest Italian warship so far in the Marina Militare, but she paled in comparison of Regia Marina designs, the Caraccoiolo and Litorrio class battleships or even the unfinished aicraft carrier Aquila (211 m long and 30,000 tonnes). She also was smallest aircraft carrier in the world at the time, considering she was completed as such. She would be dethroned by the Thai Chakri Naruebet in the 1990s.
Garibaldi received her symbolic battle flag in Naples, on October 3, 1987, delivered by the president of the National Sailors Association of Italy and by the presidency of the Italian Naval League. The flag was carried by the cruiser of the same name, WW2 Condotierri class veteran and entirely rebuilt as a missile cruiser.

Design of the class


Cutaway of the ship, from pinterest
Giuseppe Garibaldi was designed for anti-ship, anti-aircraft and anti-submarine warfare. But also perform command and control functions with a large combined force.
Thus, it had a sizeable crew and needed good accomodations to go with it. So between the core crew, needed for basic working of the ship (600), was added their air group crew, both pilots and ground personal (230), and above this, the command personnel close to 100+, and on top of it all in some conditions up to 600 troops.

The island is grouped around the single funnel, venting exhaust gases from the two propulsion units with diesel generators and auxiliary boilers (see later). This island was positioned on the starboard side, 60 meters long. It housed the command bridge, operating rooms. There two masts supporting most of the numerous electronic equipment, radars and sensors. Initially, a second continuous bridge was envisioned below the flight deck but stability rapidly imposed a more classic approach.

The design issue observed was that due to the limited width of the deck and placement of axial hangars instead of side ones, the elevators blocked communications between the two sides of the hangar during air operations, at least of aicraft recovery. Helicopter could be operated at all times from their spots, and VTOLs launched when still.

To operate at all times, Garibaldi is equipped with air conditioning. It also helps with the NBC protection for colective protection: All doors had seams and could be shut hermetically, and a constant flow of air and slight overpressure was unsured by 6 centrifugal electrocompressors, placed in pairs on three air conditioning stations. They were provided by Termomeccanica an together procured 3,000,000 Refigreration/h in summer, whereas the two heat exchangers procured 700,000 Cal/h in winter.
Hot and cold fresh water production units were distributed in 6 water tanks, four at the bow and two at the stern. They initially comprised two SCAM ScamFlash evaporators each capable of producing 120 tons daily. In 2002/2004 they were replaced by four ROCHEM-MARINE reverse osmosis desalination plants, also in pairs in the engine rooms. Hot water came from the mixed electric-steam boilers fed by 105°C steam fed by the four Bono auxiliary boilers 2 by 2 in the engine rooms, and electric heaters alternative or simultaneousl depending on onboard requests and crew size.

Hull and general design

The hull was divided into 13 watertight compartments by vertical bulkheads. Longitudinally she was given six decks and during the design phase, particular attention was paid to the hull’s external shape. A model was subjected to numerous tests at the INSEAN (National Institute for naval architecture studies and experiences) in Rome. At the request of Italcantieri, a basin was specially prepared for largeer model tests in rough sea conditions. It was also proceeded to a serie of cavitation tests on an aft shape hull section, as large as possible to be realistic. Maneuverability tests also took place on another 8.57 metre model on Lake Nemi (the famous lake on which Caligula’s floating palace once stood).

The hull as built was equipped with normal anti-roll fins and when speed exceeded 18 knots, two pairs of retractable fins went out so further stabilize her roll, powered by electro-hydraulic control. They allowed a roll reduction from 30° to just 3°, quite an achievement for a deck carrier, enabling air operation even in foul weather. There was also a system in place for a rebalancing of loads, wirh an internal sismic-type gyroscopic system that following movements by helicopters or planes. There was also transversal balancing system using two active compensation tanks located in the main area. The were filled and emptied using water expulsion using two electric pumps. The system was automatic also and contributed to counteract the roll and weight moving deck weights above. In the 1980s this was groundbreaking.

Powerplant

Garibaldi in sea trials, 1985
Garibaldi in sea trials, 1985
The propulsion scheme chosen was the new COGAG type arrangement: It comprised three sets of units working together. The powerplant area was divided into two groups separated by two other watertight compartments to survive flooding survival of at least one unit, and ship full controllability even with three adjacent compartments flooded. It comprised four General Electric/Avio LM2500 gas turbines, 60,400 kW (81,000 hp) in two twin unit rooms, and six diesel engine generators Grandi Motori Trieste B230/12, 9,360 kW (12,550 hp), coupled with electric generator Ansaldo-Elettrital, 1,560 kW (2,090 hp) each. This procured 30 knots and Range at 20 knots was approximatively 7,000 miles (13,000 km) depending on the sea conditions and use.

-Four LM 2500 gas turbines (From Avio under license from General Electric) which were rated for 25,000 HP and usually capped to 20,000 HP in order to prolongate their operational life,for a total in operation of 82,000 hp (60 MW) (4x 20,500), driving the two shafts, ending with fixed five-blade propellers.
The left transmission comprised two gas turbines placed closest to the bow, direct line, with the left propeller turning in the same direction as the turbines. The left transmission line placed starboard comprised two gas turbines closeer to the stern and reversed (the prop rotates inverse to the turbines, with a rotating arrangement of 180° of the engine for the coupling.

-Two Vulcan/Tosi reducers/reversers. There was a tranmission allowed in forward gear to turn thes inwards at a top speed of 30 knots and managed reverse of slow rotation at the lowest output available in case some systems fails. The transmission allowed using a single shaft line, driven by one or two gas turbines if needed.

-Six B230/12 diesel engine generators: They were manufactured by Grandi Motori Trieste and rated total for 9,360 kW (12,550 hp). They are coupled with electric generator Ansaldo-Elettrital developing 1,560 kW (2,090 hp) each (see later).

-A main funnel: Air was drawn to feed the turbines and boilers from stainless steel ducts independent of each machinery space and present on both sides between the 1st corridor and the flight deck. They had a smoke reducer, altair dehumidifier filters, silencers, anti-icing. Smoke and associated residues are exhausted in the island’s funnel through pipes, with gas temperature reducer and outer cooling filters to reduce her infrared signature.

Consolle_sistema_SEPA_Garibaldi
The SEPA Console
The whole powerplant is controlled from a centralized S.E.P.A. 7614 with all command and control consoles. This POC (Platform Operations Centre) relays orders from the bridge and monitors all critical systems of the power units as well as C.A.M. auxiliary for the degraded pipeline of the gas turbines located in the bow and stern.

Onboard Electric Power

Electricity needed to power all aboard systems, from the radar to the bridge, also comprises a part in the main propulsion system: The six generators (two usable in emergency) are comprose of fast diesel engines from Grandi Motori, supercharged, charging in turn three-phase synchronous alternators (from Ansaldo-Elettrital) rated for 440 V-1560 kW. They could function independently or with the four power plants and managed from the SEPA console and SACIE integrated system.
Two of these power units are located in the forward engine rooms and two in the stern rooms. The diesels are enclosed separately, in soundproofed anti-acoustic modules and had their own internal fire-fighting systems. The two emergency groups are placed in outside rooms forward and aft ensuring even with full flooding some remaining power for essential systems (like pumps). For this, they are placed on the safety bridge, with discharges port of the flight deck. The are used to power deck operation systems like aircraft engine starters.

Armament

Designed a bit as a cruiser, the Garibaldi was given a substantial self-defence capabily in case her escort would be compromise or when operating alone. Proportionally she is better armed than standard USN aicraft carrier for example, which relied more on their task force and own air group.

2×8 Selenia SAM

For medium-range air defence, the ship is equipped with two eight-cell Selenia “Albatros” hand-held missile launchers, located on the forward and aft deckhouses of the island and equipped with an exhaust gas dispersion barrier to protect the flight deck, each of which it has eight missiles ready to launch and sixteen in reserve for a total of forty-eight Aspide missiles.

8×1 OTOMAT SSM

Originally an anti-ship guided missile system based on four OTOMAT missile launchers was also installed, positioned laterally at the extreme stern, with the possibility of using a total of eight containers superimposed in pairs for the Mk-2 version with folding wings, landed in 2003 to allow an enlargement of the flight deck.

Breda OTOMAT 40mm/70

For the close anti-aircraft defense there are three twin turrets equipped with Breda 40mm/70 light cannons integrated into the Dardo point defense system; the three turrets, with a rate of fire of 300 rounds/minute (and a range of 4km against missiles and aerial targets and 12km against surface targets) are positioned so as to guarantee a 360° optical view, with two turrets positioned on the lateral sides and one at the extreme stern.

ASW Protection

For anti-submarine defence, the ship has two triple torpedo launchers of the 324mm ILAS-3 type, similar to the American MK 32 type, armed with Mk 46 and A-244 light torpedoes[14]. The same light torpedoes also equip the onboard ASW helicopters.

Sensors

Console_SADOC3
The console of the Selenia IPN 20 system

The vital center aboard was the COC (Combat Operations Center) scaning and managing all ship activities both in exercises or real crisis. It was located behind the Command Bridge and hosted the Selenia IPN 20 system collecting data from all sensors and communication arrays as part of SADOC-3 (System Automated for the Directorate of Combat Operations) receiving and processing and providing redigested information in real time, for better situation awareness, and from analogical to digital means. It was tasked of activating defensive systems according to threat level encountered and guiding combined responses.
The room comprised ten single operator vertical consoles displaying the integrated data processing system Selenia IPN-20 tracking and following a single selected activity for each, while the center two multiple consoles followed all the activities diplaying the overall tactical situation. There was also a large horizontal display console to have the most important data on sight at all time.
The Automated System for the Management of Combat Operations was pioneered on the Audace class destroyers, as part of SADOC 1 but with command-only capability, and had been expanded to Command and Control (C2), Communications (C3) and C4I (+Computer and Information tasks) with transmission by the Elmer communications system (Link 11 HF and UHF Link 14) and Link 16 from 2003.

Main Warning & Detection Radars

Hughes AN/SPS-52C: A long range air search 3D E-band radar with 400 km range working with the following:
Selenia MM/SPS-768 (RAN-3L): 3D long-range air detection radar, D band, 200 km range, fitted with IFF Mk. XII.
Selenia SPS-774 (RAN-10S): 2D radar with 150 km range, for medium range/low altitude air search fitted with IFF Mk. XIII.

FCS Radars

S.M.A. MM/SPS-702: Surface search only, 2D, band I radar installed on a bracket of the bow mast also tasked to spot low-flying air targets (like sea-skimming missiles) fitted with the MM/UPC-718 with IFF transponder MM/UPC-719 and G/H band antenna for remote control of the Teseo missiles.
Radar MM/SPS-702 CORA New antenna installed in the 1990s enclosed in a smaller radome, one the starboard vertex.
Three SPG-75 Albatross/Aspide system firing directions coupled with Selenia RTN-30X Orion radar and Elsag NA-30B Argo control unit (top of the helm station and aft of the funnel). Three SPG-74: FCS of the three Dardo CIWS, coupled with with Selenia RTN-20X radar and Elsag NA-20 control unit, close to the mounts.

Sonar

Low-frequency sonar Raytheon DE 1160LF mounted on the hull. Replaced by an Italian DMSS-2000 unit after the overhaul of 2003.

Navigation

GEM Elettronica MM/SPN-749 navigation radar: operates in band I with a peak power of 20 kW, with two separate antennas, master and slave on the bridge.
SMA MM/SPS-703 navigation radar: Planned to be placed on a shelf positioned on the bow mast below the MM/SPS-702 radar, planned but not installed.
MM/SPN-749 system: GEM Elettronica using two antennas positioned in the forward/aft areas of the island.
Tacan URN-25: Usef for aviation take-off and landing, and with radio IFR flight procedures.

Electronic Warfare

For electronic warfare operations, the unit is equipped with the integrated ESM/ECM Elettronica MM/SLQ-32 Nettuno system, whose elements operate both in ECM (Electronic Counter Measures) function active for disturb and deceive enemy radars and enemy missile guidance systems, both in passive ESM (Electronic Support Measures) function, for the localization and analysis of emissions from electronic equipment deemed not friendly.

AN/SLQ-25 Nixie system: Electronic anti-torpedo protection system, NATO stan,dard. It is given a source of anti-torpedo decoys emitting fake propeller/engine noises deceive and deflecting incoming torpedoes. Replaced by the AN/SLQ-25B with better sensors locating incoming torpedoes.
Breda SCLAR launchers: Located on the aft part of the island are two twenty launcher 105mm flares/chaff for missile jamming. After 2003 they were repositioned.

Air Facilities


She had a through deck with an island with a total superficy of 5,000m² (), and below a 1,650m² () hangar for a total parking space of 9,900m³ (). The Flight deck measured 173.8 meters long by 30.4 meters wide (). The Hangar measured 110 meters long by 15 wide and 6 meters tall, served by two elevators of a semi-rounded shape, each measuring 18 m long for 10 m wide () and 15 tonnes ( Ibs.). There was no catapult but a 6.5°-inclined, 28.5 meters long () ski-jump.


The Deck configuration of the aircraft carrier Giuseppe Garibaldi comprised an offset setting from the longitudinal axis. The in-construction addition of a ski-jump inclined at 6° had a total superficy of 174 meters for 30 meters, with the excluzion area formed by the large island. The deck was surrounded by a side walkway for safe personnel movement, the arrangement of ancillary equipment: Refueling points, power sockets, fire-fighting services. This walkway was placed one meter below the flight deck. To compensate for the slight increase in height with the bow, further improvement of the ship stability in rough sea conditions was done (as seen above for the hull design).


The hangar below the flight deck was divided into three sections for fire fighting with rapid-closing fire proof curtains, and two rigid fire walls. Sprinklers and smoke detection systems were also installed under the roof. The decks elevators could carry 18 tons, and hed been provided by Navalimpianti. They were placed respectively forward and aft of the island superstructure and practically aligned with it.
There were deck sprinklers, enabling to clean the deck from combustion residues, but also to rapidly extinguish any fires. Markings comprised a straight track in white (the deck was dark grey), running straight from aft to bow, parallel to the island, and divided into six areas and four internal guiding lines for the jets. However there was a further marking, double lines colored in black off-set for VTOL landings. It was not usable when the six spots were used though. The latter was also placed to the port side, three parallel and two more inwards the deck, the last being placed at the end of the forward deck section.

Air Group

The first fixed-wing aircrafts of the Italian Navy


Due to the legislation from 1923 banning fixed-wing military aircraft from the Navy, the Giuseppe Garibaldi had to wait for the law being changed in 1989. It was expected sooner, and during construction a ski-jump was added. The Law 36 of 1 February 1989 authorized this and given the size of the ship, any CATOBAR configuration with catapults was out of questions. The choice fell early on to British Sea Harrier and its more modern equivalent AV-8 Harrier II.

The latter was chosen due to its most sophisticated multi-mode radar, equal to the one carried by the F/A 18 Hornet. In 1990 the order of two AV-8B+ was confirmed and soon pilots and technicians were sent for training in the US. On June 7, 1991 official delivery took place at the Marine base of Cherry Point in North Carolina. They were received aboard Garibaldi on August 23 aboard the Garibaldi as she was moored off Norfolk, Virginia.
Garibaldi only embarked them operationally at the end of 1991 for international exercises with flight deck operations going on through NATO Dragon Hammer 90.. Italy was part of the coalition deployed against Iraq in the first gulf war and these came right on point. The park comprised both Sea Harrier in the single and dual seat versions (the latter being called TAV-8B). It is assumed they carried ten single-seat and two dual seat versions.
(to come)
HD Author’s illustration of an Italian AV8B Harrier

Helicopter Group


(to come)
HD Author’s illustration of a Sea King SH3D of Garibaldi


HD Author’s old illustration of a Sea King SH3D

Old Author’s illustration of the AB-212

Old Author’s illustration of an Italian AW-101
Her final air component was to be alternatively composed of up to a maximum of 12 STOVL AV aircraft of the 8B Harrier II and 6 helicopters for a total of 18 aircraft total, 12 parked in her Hangar and 6 on the flight deck, although she had a total capacity of 36 when taxing them. She also could only take aboard 18 Agusta SH-3D helicopters.
However it varied in time:

In 1990 she carried typically 16 SH-3D Sea King. In 1991 she received her first two AV8s and more followed in 1992-93. In 2005 she had a permanent park of six AV-8B Harrier and four SH-3D Sea King. In 2012 this went up to ten AV-8B Harrier (she only had a nominal capacity of 12) and a single SH-3D Sea King and the latter in 2017 was replaced by an AW101 AEW Merlin. But in 2017 she retained an all-helicopter park of eighteen AW101 Merlin, AW101 AEW Merlin and NH90 NFH models.

giuseppe garibaldi profile
Conway’s profile

⚙ specifications

Displacement 10,100 t standard, 13,850 t FL and 14,150 t after 2003 MLU
Dimensions 180.2 x 33.4 x 8.2 m (591 x 110 x 27 ft)
Propulsion 4× GE/Avio LM2500 GTs 60,400 kW (81,000 hp), 6× diesel Gen. 9,360 kW (12,550 hp), electric Gen. 1,560 kW (2,090 hp)
Speed 30 kn (56 km/h; 35 mph)+
Range 7,000 nmi (13,000 km; 8,100 mi) at 20 kn (37 km/h; 23 mph)
Armament 2×8 Mk.29 Sea Sparrow/ Aspide SAM, 3×2 40L70 DARDO 2× 324 mm TTs, 4× Otomat Mk 2 SSMs
Air Group 12 AV-8B Harrier II/ASH-3D/AW101 helicopters
Sensors MM/SPS-768, SPS-774, AN/SPS-52C, SPS-702, SPN-749 nav, SPN-728, 3x RTN-30X & RTN-20X FCR, DE 1160 LF sonar, CMS SADOC-3 TACAN URN-25, SLQ-732, 2x SCLAR, AN/SLQ-25 Nixie
Crew 830: 550 Crew, 180 Fleet Air Arm, 100 C4 staff

Reception and Modifications

The hangar was designed to accommodate either twelve SH-3D Sea King helicopters or ten AV-8B and one Sea King. Garibaldi was ordered on 20 February 1978, starting sea trials on 3 December 1984 and in about c1990 the original four Otomat SSMs was replaced by eight Otomat 2 SSMS (folding wing type). Only four missiles are usually carried, however. She is equipped as a fleet flagship and also serves as an ‘interpreter’ between the on-shore Italian air defence system and deployed ships (their electronic data links are not compatible with the land-based system). Like the British Invincible class she can carry troops (up to 600).
So in the late 1980s her four single Otomat Mk 1 SSM were replaced by four twin Teseo Mk 2 SSM (8 Otomat Mk 2) and in 2004, the latter were removed as well as the SPN-728(v)1, SPN-749(v)2 radars and DE1160 sonar: Her electronics suite was completely modernized with the installation of a SPS-753 radar, DMS 2000 sonar and SLAT anti-torpedo system.

Succession


Italian aircraft carrier Cavour in the Gulf of Oman, 2013, with the USS Harry S. Truman (CVN 75, 5th fleet) and FS Charles de Gaulle in the background as TF 473.
A second, larger, ship was planned as of 1995, with possible names are Giuseppe Mazzini or Conti di Cavour (which was the name chosen in the end). This programme was confirmed in 2000 after a long gestation and construction started of a far greater ships displacing 30,000 tonnes (29,900 t) fully loaded, launched 20 july 2004 and completed 27 marzo 2008, the costiest and largest Italian warship ever. In capabilities head and shoulders above the Garibaldi albeit with the same basic requirements, she carried up to 36 VTOL aicraft and helicopters between her deck and hangar, with a permanent park of ten STOVL/V/STOL Harrier II AV-8B and/or F-35B and well as 12 EH-101 AEW/ASW, SH-3D, and AB-212 ASW or NFH-90.

Garibaldi in 1988

Garibaldi in 1988
Garibaldi in 1988

Garibaldi (C550) Entered service on 30 September 1985, and was assigned to the 2nd Naval Group, 2nd Division in Taranto. She acted as flagship and headquarters, CiC Naval Squadron. Her first arir group of AB212 helicopters was soon partly replaced by EH101s and she soon took part in intense fleet training and representation activities with several goodwill visits in 1985-91. In the summer of 1991 she sailed to the US for the first time and taked part in the ceremony delivery of her first two two-seat TAV-8B, returning to Italy on 24 September 1991, the two Harrier beiong sent to Grottaglie AB. It seems she took no part at this stage to Operations in the first gulf war.

Crisis in Somalia
She next took part in Indian Ocean operations and the crisis in Somalia. In 1994 she was part of Ibis II mission as command ship for 25th Naval Group centered around her, with the supply ship Stromboli, LPDs San Giorgio and San Marco and covered by the Frigate Scirocco. They covered the Italian contingent deployed there for Operation Restore Hope.

Garibaldi and USS America in 1996
Garibaldi and USS America in 1996

By the spring of 1994 Garibaldi sailed back a second time for the United States and to receive tthree AV-8B+ single-seat, also visiting Baltimore, Boston and New York. Back to Italy, from 11 January and 23 March 1995 she was back in Somali waters for Ibis III, covering the withdrawal of US peace contingent, also acting as command ship for the 26th Naval Group, with Scirocco relieved by Libeccio. Three AV-8B Harrier II , two SH-3D, four AB-212 NLA and four A-129 Mangusta (Army attack helicopter) operated together. The ship also hosted 198 paratroopers and cavary units, 320 men of the San Marco battalion and 30 Comsubin commandos.
From March to June 1997, she took part in Operation Alba Neo off Albania with the air group from Grottaglie AB. F
ollowing the reorganization of the Fleet of 1999, she was assigned to COMFORAL (Offshore Forces Command) in Taranto.

Garibaldi moored in Taranto, early life
Garibaldi moored in Taranto, early life

Kosovo war:
In 1999, she took part in the Kosovo war, Operation Allied Force. Her AV-8B II+ Harrier carried out 30 sorties, 63 flight hours. They used Mk 82 and GBU-16 bombs, AGM-65 Maverick missiles during the operation. The Italian naval force was also covered by the frigate Zeffiro.

Operation Enduring Freedom
Following the attacks of 11 September 2001 Italy a,swered the call for Operation Enduring Freedom. Garibaldi became the command ship of GRUPNAVIT I (1st Italian naval group) which was escorted by Zeffiro, Aviere and refueler Etna. The group left Taranto on 18 November 2001 for the Indian Oceanvia Suez, operating there from 3 December 2001 to the 1 March 2002, and back to Taranto on 18 March 2002. Garibaldi’s AV-8B Harriers performed 288 flights over 860 hours with a mission of control and interception as well as air support and interdiction over Afghanistan.

2003 modernization

In 2003, Guiseppe Garibaldi started modernization brining her C4I capabilities and Teseo launchers removed, one SCLAR rocket launcher repositioned for an extension of her starboard aft flight deck. She had a completely new Maritime Coordination Center and data system large enough for 100 personal, new SATCOM communication system with data Link 11, 14, 16 and Wide Area Network (WAN), new sonar. After recommissioniong, she took part in NATO Exercize Majestic Eaglein the Atlantic by 2004.

Garibaldi underway in the Atlantic Ocean
Garibaldi underway in the Atlantic Ocean

2000s Operations

In the summer of 2006, she sortied to take part in the Lebanon crisis but participating first to Operation Mimosa ’06 and Operation Leonte with San Giusto and San Marco, San Giorgio, covered by the frigate Aliseo, destroyer Durand de La Penne. They arrived in the port of Beirut now secured by the San Marco Regiment. A large tonnage of relief aid for the population was landed, including field kitchens, ambulances, electric generators, pneumatic tents, medicine & food delivered by the Italian Ministry of Foreign Affairs, Civil Protection and Italian Red Cross as well as the UN World Food Programme.

Garibaldi off Malaga, 2004
Garibaldi off Malaga, 2004

Mimosa 06 operation had Durand de la Penne sailing out for an exercise in Greece, and later enter the port of Beirut to evacuate compatriots and other Europeans to Cyprus in trips. The San Marco battalion landing from San Giusto nad carrying first relief for the population and proceeding to further evacuations. Operation Leonte in September was under a UN resolution as part of UNIFIL 2. Garibaldi, San Giusto, San Giorgio and San Marco under escort of the corvette Fenice, made a demonstration of Italy’s full amphibious forces and capabilities of Projection force when landed in Tire beach. The “San Marco” Marine Brigade and Lagunari regiment took part in it.
Fior this, Garibaldu deployed her air group for reconnaissance missions on merchant traffic off the Lebanese coast, preventing arms smuggling. Giuseppe Garibaldi was joined the brand new commissioned Conte di Cavour, just completed in 2008 and operational since 2009. She was to replace Vittorio Veneto placed in reserve since 2003. Cavour became the new flagship of the Marina Militare and the fleet deployed in Lebanon.

In September 2008, Garibaldi left for Italy, entiring the drydock for a new long maintenance work scheduled and overdue for years. This 2008 overhaul was in fact the first time the fleet had the Cavour, not yet fully operational as sole aicraft carrier of the Marina Militare available, acting as new flagship.

Garibaldi and Charles de Gaulle
Garibaldi and Charles de Gaulle

Libya: Operation Unified Protector (2011)
Back to service, Garibaldi took part in Operation Unified Protector dealing with the Libyan civil war, and taking active part in the coalition support to the rebels against Ghadaffi. She had by the time eight Harrier available put to good use withing NATO frame, and took the role of command vessel from 25 March to 26 July. Her AV-8B Harrier IIs launched 160 laser-guided missiles/bombs strikes (1221 flight hours total).

2013 Modernization and subsequent Operations

After the navy reorganization of 2013 Garibaldi was assigned to COMGRUPNAVIT together with San Giorgio, San Marco and San Giusto, creating the main Italian assault group whereas Cavour was to act more as a fleet task force center. From 12 September 2014, various commands reaorganized around main bases, made Garibaldi’s group renamed COMGRUPNAV 3, and the ship was tasked to act as command of the naval group and coordinate a national/multinational amphibious force withing NATO procedures.

This 3rd Naval Group consituted the core of the “projection force from the sea”, operating notably the “San Marco” marine brigade Helicopter Assault Department as main air component, meaning Garibaldi’s air group was modified to be more helicopter-centered.
On 13 October 2013 Garibaldi was transferred to the military maritime arsenal of Taranto and was overhauled and modernized again for her service to be extended until 2022.
The work involved almost all of the ship’s systems, mainly concerning the propulsion system, all auxiliary systems, (generators, maintenance systems), plus a full careening, removal of asbestos. The overhaul was to last until 15 March 2015 at an estimated cost of 11 million euros, but was completed ahread of schedule in November 2014 with perfect budget restraint.

Exercize Dragon Hammer, 3 May 1990
Exercize Dragon Hammer, 3 May 1990

She had new gas turbines, new diesel generators, new electrical network, new flight deck, all support systems for flight operations modernized, new air conditioning system, new lits, cranes, deck vehicles, equipment, hull accessories and finally full overhaul of the armaments of main combat system, electronics. Her oil bilge water treatment system was also made conform to internaitonal ecological regulations, and so was the new painting treatment of the hull, ensuring a longer life and with a coating unsuring fuel consumption lowered by 8-13% and to reduce CO2 emissions. In total her paint was on 5,200 m² of her hull and 4,400 m² of flight deck. But it went beyond as 30 tons of external plating as been replaced, 29,348 m³ treated, 4,880 meters of piping replaced.


Garibaldi, Foch and Asturias in Dragon Hammer 1992

By June 2016, recommissioned and after refreshing training, she became flagship of Operation Sophia, EUNAVFOR mission, replacing Cavour which herself underwent her first overhaul. On 22 August 2016, off Ventotene island she hosted an UE summit between Italian PM Matteo Renzi, French Pdt. François Hollande and German Chancellor Angela Merkel. This laied the groundwork for larger Bratislava meeting, after the Brexit.

040712-N-7748K-0620.Atlantic Ocean (July 12, 2004) –The USS Hary S. Truman (CVN 75) and the Italian aircraft carrier ITS Giuseppe Garibaldi (C 551) steam together through the Atlantic Ocean while participating in Majestic Eagle 2004. Majestic Eagle is a multinational exercise involving multiple allied nations working side by side in a realistic and challenging training environment to prepare for and conduct integrated operations with multiple aircraft carriers and other vessels. Official U.S. Navy photo by Photographer’s Mate Airman Josh Kinter. Image released by LT. K.R. Stephens, PAO-CVN-65. . . . .


A new career to the horizon ?

In 2021, the General Staff decided not to withdraw Garibaldi despite her incoming retirement date. The expected entry into service of Trieste in 2023 was to mark her official retirement indeed, but it was decided to maintain Garibaldi as platform for the national space strategy, as part of the Joint Force Command for Space Operations, putting her communication systems to good use.

Read More/Src


Official photo, src: marina.difesa.it

Books

Robert Gardiner Conway’s All the World’s Fighting Ships 1947-1995, NIP 1996

Links

https://www.globalsecurity.org/military/world/europe/garibaldi.htm
https://www.naval-technology.com/projects/garibaldi/
https://web.archive.org/web/20070905015227/http://www.navytrieste.com/nave_garibaldi_c_551.htm
https://www.militaryfactory.com/ships/detail.php?ship_id=Giuseppe-Garibaldi-551
https://www.marina.difesa.it/Pagine/Search.aspx?k=giuseppe%20garibaldi
https://en.wikipedia.org/wiki/Italian_aircraft_carrier_Giuseppe_Garibaldi
https://it.wikipedia.org/wiki/Giuseppe_Garibaldi_(C_551)
http://navypedia.org/ships/italy/it_cv_giuseppe_garibaldi.htm

Model Kits

Apparently they had been 1/700 scale kits by Tamiya and Fujimi (waterline kits). – More to come.

Mahan class destroyers (1935)

uss shaw

Mahan class Destroyers (1935)

US Navy Fleet Destroyers (1934-48): USS Mahan, Cummings, Drayton, Lamson, Flusser, Reid, Case, Conyngham, Cassin, Shaw, Tucker, Downes, Cushing, Perkins, Smith, Preston, Dunlap, Fanning

WW2 US DDs:
Wickes class | Clemson class | Farragut class | Porter class | Mahan class | Gridley class | Bagley class | Somers class | Benham class | Sims class | Benson/Gleaves class | Fletcher class | Allen M. Sumner class | Gearing class

The Mahan-class were 18 standard fleet destroyers, 16 planned FY33 and laid down in 1934 and the last two (Dunlap and Fanning) FY34, all commissioned in 1936-1937. They were an improvement over the Farraguts, less on stability but more on armament with no less than 12 torpedo tubes and other innovations on a larger, 1,500 tons displacement. They also had a new steam propulsion system, lighter and more efficient and soon a standard of USN destroyers. They all saw action in the Pacific, notably Guadalcanal, Santa Cruz Islands, Leyte Gulf, or Iwo Jima. In between they performed a lot of different tasks with six lost in action, earning collectively 111 battle stars. #ww2 #usn #mahan #destroyers

Design Development and Construction

The Mahan-class destroyers were logical follows-up of the Farragut class. The admiralty board had the standard fleet destroyer validated and wanted a larger class with improvements when first planned in early 1933. On the design stage already the Farragut class destroyers were criticised by the USN chief staff for insufficient torpedo armament. It was made clear the following FY1933 class would require an upgrade on this point of view.
Notably members of the board fell in agreement with the choice of machinery, and wanted the most up-to-date arrangement possible, for better speed and range (this came later).
But the General Board mostly dealt with armament changes:
-The first proposal went with 12 torpedo tubes, to the sacrifice of a single 5-inch (127 mm)/38 gun.
-Next, it was proposed to retain all five guns AND the twelve torpedo tubes upgrade. The tradeoff was to have surface-capable guns only, which had simpler and lighter mounts.
The Chief of Naval Operations (CNO) objected to this being against the new trend of versatile AA/surface defence role for the fleet. In his own terms he refused “subordinating the gun to the torpedo”
-Eventually a compromise was struck: A new engineering plant would be installed (after Gibbs & Cox’s proposal, see after), a new battery arrangement with No.3 gun moved to the aft deckhouse, ahead of No.4 mount. This cleared up the rear amidship section, enabling a third quadruple torpedo tube to be installed. Then, the two middle torpedo tube banks were moved to the sides, the centerline being used for a larger aft deckhouse.
This design had the merit to keep all planned dual five 5 in/38s. The tradeoff was that only the first two had gun shields (With the sub-class Dunlap they were swapped for brand new enclosed mounts).

The machinery was revolutionary at least on a destroyer: They were basically an adaptation of a land-based machinery, a new generation of steam propulsion system combining greater pressure and temperature, combined with a new generation lightweight steam turbine. There were less parts, and it was overall simpler and more efficient, easier to maintain and more economical. The use of double reduction gearing als helped to further reduce the size and weight of the turbine. The space was used to add low-pressure cruising turbines, helping to regain extra range as well. This was still paid globally wit 10% more displacement compared to the Farragut class.

The Mahans as approved and programmed FY1937 (first 16 vessels) under the NIRA Executive Order on 16 June 1933. The last two were authorised under the Vinson-Trammell Act of 27 March 1934 (as part of 95 destroyers up to DD-482). Contracts for the first six were attributed to three shipbuilders which lacked for the Navy an acceptable in-house design structure. Therefore New York’s Gibbs & Cox stepped forward as primary design agent. Having no experience but perfectly well-versed in passenger-cargo liners, especially for their innovative propulsion systems, they managed to attract the attention of the US Navy and were given also the design of the Farraguts. Naturally they were contacted for the Mahan class also. They promised a cheaper, faster, more efficient propulsion system with the systems seen above. This proved a revolution for US destroyer design.

Design of the class


ONI Rendition of the Mahan class


Detailed plans of USS Cushing. src

Hull and general design


2-views of the DD-376 in 1942. src: Unknown, from pinterest.
The Mahans were a tad larger and much heavier than the Farraguts, at 1,500 long tons (1,524 t) standard and up to 1,725 long tons (1,753 t) deeply loaded. They reached 341 feet 3 inches (104.0 m) in lenght, by 35 feet 6 inches (10.8 m) in beam, for a 10 feet 7 inches (3.2 m) drag=ught (normal). The Mahans had a tripod foremast and pole mainmast aft, but for better AA field of fire, no nautical rigging went bracing the tripod. The silhouette was in fact more reminiscent of the larger Porter-class destroyers.
The Mahans were fitted with the first emergency generators, which replaced the storage batteries of earlier classes. Gun crew shelters were built for the superimposed weapons, one shelter before the bridge and one atop the shelter deck aft. Their Complement reach approximately 250 officers and enlisted men.
These ships also carried among other equipments two signal lamps on the bridge’s wings, a single 24-in Model 24-G-20 searchlight on a platform aft of the rear funnel, in between TTs.
They also had two cutters under davits abaft the forefunnel-bridge as well as 12 life rafts, carried already inflated.

Powerplant

The propulsion was considerably improved over the Farragut standard as saw above. They had brand new lighweight and compact General Electric geared steam turbines (impulse-type, also called Curtis turbines). They drove two shafts for a total output of 46-48,000 shaft horsepower (34-36,000 kW) – The Farraguts went to 42,800 shp (31,900 kW) in comparison. Steam came from four also brand new Babcock & Wilcox/Foster Wheeler water-tube boilers. Steam was supereheated, raised from from 400 psi (2,800 kPa) to 465 psi (3,210 kPa) and reaching in temperature 648 °F (342 °C) to 700 °F (371 °C). Steam from the boilers went to the HP turbine, exhausted to the LP turbine, exhausted to the condenser.
The other innovation in the turbines was their Double reduction gearing making for smaller and faster-turning turbines. They were divided into a high-pressure and low-pressure turbines feeding the common reduction. The space freed was occupied by cruising turbines improving fuel economy at lower speeds. Boiler economizers also allowed to improve fuel economy as the latter was heated before being injected.
In all, the Mahans carried 523 long tons (531 t) of fuel oil enabling 6,940 nautical miles (12,850 km; 7,990 mi) at 12 knots, so far better than the Farraguts. Range increased was thus 1,000 nmi (1,900 km; 1,200 mi). All this came withing the same same space and weight as in the Farragut class hull.

Armament

2-view of USS Cushing, showing the position of the torpedo tubes, main and secondary armament in 1942
2-view of USS Cushing, showing the position of the torpedo tubes, main and secondary armament in 1942 (the blueprints)

USS Lamson at Mare Island after transformations, 29 May 1944, ONI

USS Cushing transformations at Mare Island Arsenal 15 July 1942, ONI

Main: 5x 5-in/38 guns


The main battery comprised five dual purpose 5-inch (127 mm)/38 caliber guns Mark 12 Mod 0, as for the Farraguts. They were matched with single Open/Open-back Shield Pedestal Mounts Mark 21.
However they were served by the new Mark 33 gun fire-control system (see later). Forward gun shields only.
The real novelty however was the introduction of fully enclosed Mark 25 mounts on the last two ships, USS Dunlap and Fanning (DD-384/385). They also introduced the Mark 24 Mod 0 and Mod 1 stern mounts. They were completed as such, with the two Mark 25 enclosed mountings a the bow, three Mark 24 pedestal mounts at the stern. This is the only reasons they are considered by some as a sub-class within the Mahan class. All previous vessels only had Mark 21 pedestal mounts on all five positions.


Mark 25 Mod 0 specs:
Weight 42,000-44,900 lbs. (19,051-20,367 kg)
Elevation rate 15 degrees per second for 15/+85 degrees
Train rate 28.7 degrees per second
Gun recoil 15 in or 38 cm

weaponry overview Mahan class

Torpedoes

mark 15 fired uss dunlap
USS Dunlap firing its Mark 15
Engineers found ways to shoehorn carry 12 torpedo tubes instead of eight. In three quadruple torpedo tube mounts. The Mark 11, then Mark 12 torpedoes were guided by the Mark 27 torpedo fire control system. The infamous Mark 15 torpedo became the new standard in 1938.
Mark 15 Torpedoes:

⚙ Mark 15 Mod 0 Torpedoes Specifications

Design/Introduction, Type 1934/35, Surface ships
Weight/neg.buoyancy 3,438 lbs. (1,55 kg)/1,260 lbs. (572 kg)
Dimensions 22 ft 7 in (6.883 m)
Propulsion Wet-Heater steam turbine
Warhead Mod 0: 494 lbs. (224 kg) TNT
Settings (Yds/kts) 6,000/45 – 10,000/33.5 – 15,000/26.5
Guidance Mark 12 Mod 3 gyro

AA armament

Thsy only had four single .50 caliber machine guns (12.7 mm) heavy machine guns for anti-aicraft defence. This was deemed enough at the time (1933). They were located on a platform (2) forward and below the bridge, the last pair on the deck house forward of 5-in mount.
This was of course considerably reinforced during the war (see below).

Depth Charges Armament

Stern view showing the two aft guns and depht charge racks
Stern view showing the two aft guns and depht charge racks, USS Case.
They were fitted with two Depth charge roll-off stern racks, of ten each, 20 in all (noreloads). From 1942, four additional Y-Guns depth-charges thrower (3 reloads each) were added amidships, abeam the aft deckhouse, for better escort operation in the Atlantic, with circa 44 DCs in stock total.

Fire Control & Sensors

Mk33 Gun Fire Control System:

A Mk.33 on USS Henley
A Mk.33 on USS Henley (Bagley class)
The Mark 33 GFCS was the great destroyer stabdard Fire Control System, associated to the Mark 10 Rangekeeper analog fire-control computer. The rangekeeper was mounted the open director atop the bridge rather than in a separate plotting room. This was not the case with the following Mark 37 GFCS. Firing solutions were computed for targets moving at up to 320 knots or 400 knots in a dive.

An interwar generation, they had no fire-control radar initially. After 1942, some directors were enclosed with a Mark 4 fire-control radar added ontop. Other had a Mark 4 radar added over the open director. The latter enabled ranges up to 40,000 yards but more commonly 30,000 yards. Radar enabled to hit accurately vessels at night or in any weather. The Mark 33 used tachymetric target motion prediction and was overall satisfactory but was still heavy and suffered wartime production problems resolved by the Mark 37.
The computing mechanisms Mark 10 were found too slow though to reach initial solutions and changing it while in motion. The problem that before a new system could be installed, spaced needed to be found in the design below decks. The Mark 33 was also clearly inadequate against fast-moving aviation. The system still was to wait for the better Mark 37 to be installed, on later ship. The Mark 33 remained operational by default on the Farraguts, Mahan, Gridley, Bagley and Benham up to their decommission.

SC radar:

sc radar The great USN standard radar from 1942, fitted mostly on destroyers and light ships in general. The SC family sets had an “A” scope and IFF connections asw ell as gyro-compass repeater link.
The SC -and early SC-1- had a max reliable range of 30 miles for medium bombers at 1,000′ altitude. With preamplifier on the later SC-1 and SC-2/3, this was ported to a whooping 75 miles.
Range accuracy of the SC was ± 200 yards, later ± 100 yds on the SC-1 whereas bearing accuracy was ± 5°.
Made by General Electric it was a 220 kW Air/Surface-search radar working on VHF band at 60 Hz PRF, ofering a Beamwidth of 10–25°, Pulsewidth of 4–5 μs and range of 48–120 km (30–75 mi) with a precision of 90–180 m (98–197 yd).

Other sensors

SG Radar: 50 KW Surface Search Frq 3 GHz PRF 775/800/825, Bmwdt 5.6°/15°, Pwdt 1.3–2 μs RPM 4/8/12, Range 15 nmi @200 yd*
Mk 12.22 radar: Medium Wave Fire Control for Dual Purpose Batteries, goes with the Mark 37 FC Director*
QCA Sonar: Early type, spherical, underwater. Manufactured by CMB. 24 cycles frequenty, M/S spherical projector, 400 Watts, electric hoist and train*
*according to navypedia

Modifications

In early 1942, the Mahan-class destroyers had their AA armament improved but full refits only started for all ships until 1944. Most notably the need for more AA dictated the removal of one 5-inch/38 gun which was replaced by a learge platform accomodating two twin Bofors 40 mm guns (1.6 in) on each wing. Room was also found to shoehorn between four and six 20 mm Oerlikon (0.79 in) guns.

In January 1945, the two quadruple side torpedo tubes were also removed amidst kamikaze attacks, replaced by two 40 mm quad mounts, quite a useful move. In June 1945 the third centerline tube was also removed (leaving the destroyers without their close quarter surface best armament) accomodating two more 40 mm twin mounts behind the funnel. Directors for theser new 40 mm mounts were also added, as the Mark 33 FCS were ill-adapted for the task. These Mark 51s FCS were to replaced by new the GFFC Mark 63 installations with radar at the very end of the war, kept after it.

As for details: By early 1942, USS Mahan, Cummings, Drayton, Lamson, Flusser, Reid, Case, Tucker, Cushing, Perkins, Smith, Preston, Dunlap, Fanning had their admidship 127mm/38 as well as the four cal.05 browning removed. Seven single 20mm/70 Mk 4 were added as well as four 4 DCT (depht charge throwers) in addition to their two racks. This ported the provision to 44 DCs in all.

USS Conyngham in very early 1942 differed by keeping two of her 12.7mm/90 Browning HMGs and having only two 20mm/70 Mk 4 added as well as four twin 12.7mm/90 Brownings and still four DCT (44 DC at all). By late 1942, USS Shaw also kept two 0.5 cal. HMGs, but she was the only one fitted woth a quadruple 28mm/75 Mk 1 mount as well as four Oerlikon and four DCTs.

Between 1942 and 1944 except for USS Cassin and Downes they were fitted with a SC radar, a SG and Mk 12.22 radars.
Frm January 1943 to the summer of 1944, Mahan, Cummings, Drayton, Lamson, Flusser, Reid, Case, Perkins, Smith, Dunlap, Fanning obtained two more single Oerlikon guns and two twin 40mm/56 Mk 1.2 Bofors. USS Conyngham by the spring of 1943 hed four twin 12.7mm/90 and single 5-in/38 amidship removed, two 12.7mm/90 and two twin 40mm/56 Mk 1.2 bofors as well as three single 20mm/70 Mk 4.
USS Shaw in late 1943 had her “chicago piano” removed and instead two twin 40mm/56 Mk 1.2 added as a single 20mm/70 Mk 4
In 1944 USS Dunlap was the first to lost her central quad 533mm TT bank.

In 1945, most spectacular changes were made:
By January, USS Lamson had two twin Bofors removed as well as two side quad TT banks for the addition of two quad 40mm/56 Mk 1.2
In June, USS Shaw lost a main guns, all her TTs and five Oerlikon guns for the addition of two quad 40mm/56 Mk 1.2, and two twin 20mm/70 Mk 4.
Last to be upgraded during the war (in August), was USS Lamson which lost a quad TT.
In 1946, DD365, 368, 370, 371, 378, 385 typically had four 127mm/38 Mk 21 left, two twin 40mm/60 Mk 1, five single 20mm/70 Mk 10, all their TTs as well as 4 DCT, 2 DCR and a QCA sonar in addition to their unchaged radars since 1942. DD367 had lost all her TT banks, DD372 and 375 had two and DD384 as well.

USS Dunlap (DD-384-386) sub-class

The Dunlap class was a two-ship destroyer class, based on the Mahan design with some sources separating them entirely. However based on my reliance on Conway’s and practicity, these were integrated here. They did not share however the following numbers, but jumped a serie since the previous 16 ships stopped at DD-379. USS Dunlap (DD-384) and USS Fanning (DD-385), shared the same hull, powerplant, armament, but differed in having the the new Mark 25 enclosed mount fitted on two forward 5-inch/38 guns.

Their particularity were to have base rings housing projectile hoists rotating with the guns and with the ammunition fed from a handling room below, enabling much faster firing. Dunlap and Fanning were the first USN destroyers ever to have enclosed gun mounts, better protecting the crew compared to shields. They aldo had a light pole foremast and no mainmast, being lighter, less top-heavy compared to the Mahans and a way to go for future US destroyers in general.

Appearance


Old author’s profile


HD rendition of USS Mahan, as commissioned in 1938. Note the tripod foremast and pole mainmast aft od the funnel. In 1939 this one was removed and replaced by small half-mast aft of the funnel. Standard Ocean Grey and large pennant markings were the norm as through the neutrality patrols of 1941.


Same ship, different timeline, showing her wartime modifications by late 1944 in the Philippines, shortly before she was attacked by Kamikazes (and sunk).

ONI pattern sheet MS-32, 3D for the Mahan class, port view
ONI pattern sheet MS-32, 3D for the Mahan class, port view.

⚙ Mahan class specifications

Displacement 1,500 long tons standard 1,725 long tons (1,753 t) deep load (2,103 1945)
Dimensions 341 feet 3 inches x 35 feet 6 inches x 10 feet 7 inches (104 x 10.8 x 3.2 m)
Propulsion 2 GE GS turbines, 4 boilers B&W/Forster, 46,000 shp (34,000 kW)
Speed 37 knots (69 km/h)
Range 6,940 nmi (12,850 km; 7,990 mi) at 12 knots (22 km/h; 14 mph)
Armament 5×5-in/38 guns, 3×4 21-in TTs, 4x 0.5 in cal. M2HB AA, 2 DCR
Sensors Mk33 GFCS, SC radar, see notes
Crew 158 (peacetime) 250 (wartime)

General Assessment of the class


USS South Dakota alongside USS Prometheus (AR-3) and two Mahan class DDs off North Africa, November 1942

Design wise, with a brand new, innovative machinery offering many innovations and advantages, and 12 torpedo tubes, plus their superimposed gun shelters as well as generators, the 135 tons increase over the Farraguts seems well used overall. The class was capable to raise steam faster, being more efficient and thus, having a better range, requiring less maintenance-intensive machinery (which went with lesser skilled specialists). The Mahans became therefore the new standard for US destroyers. The Farraguts, top-heavy and unwieldy, certainly paled in comparison. This design evolution however was not “in-house” but rather the external contrution of Gibbs & Cox flair for innovative machinery.

If transatlantic liners can have the world’s best machinery systems (which was often the case) these ships were seen very much as showcases of national tech. So why not make the best of US taxpayers by recycling these to the military. The advance taken by the USN in that matter (to compare with other fleets) also explains in part why US WW2 destroyers in general saw so much useful post-war service, for some until the 1990s. The base principe was kept with constant improvements between the Fletcher, Sumner and Gearings.

USS Perkins dealing with heavy weather, date unknown
USS Perkins dealing with heavy weather, date unknown

All 18 ships saw action in World War II and all in the Pacific Theater (after some service in the Mediterranean/Atlantic). They saw the most important engagements of the war (unlike for the exmple the numerous Fletcher class), and that included the Guadalcanal Campaign, battle of the Santa Cruz Islands, Battle of Leyte Gulf, and battle of Iwo Jima. They were “do-it-all-ships”, always on the breach for a variety of missions, between beachhead bombardment, close cover of amphibious landings, and traditional task force screening as well as convoy and patrols. She were tasked for anti-aircraft cover when integrated with task forces, and submarine warfare when detached in waters surrounding the area of operations (usually atolls and island coasts).

DD-366 in 1944
DD-366 in 1944

Six were lost in action (plus two expended in Operation Crossroads nuclear tests). The remainder were all scrapped due to their age conception, but they still saw reasonable service of about ten years before commission in 1936 and 1946-48 retirement. Ten years was short, still for taxpayer’s money. But their wartime service was particularly intense, and they chronically lacked proper maintenance, and having heavy use of her equipments and powerplant in particular, despite their innovative nature.

In short: In 1945 they were worn out. None survived today precisely because of this early retirement. Only the Fletcher class generation served long enough in the cold war to generate such preservation interest (and a new context, with more cash and veteran’s weight in the society for such enterprises). This was no a thing back post-WW2. Collectively their 111 battle stars testify this long, intense, even relentless World War II service. With one third of the class lost in action, this was indeed a rather high ratio for USN Destroyers.






Read More

Books

Bauer, K. Jack; Roberts, Stephen S. (1991). Register of Ships of the U.S. Navy, 1775–1990. Greenwood Press.
Friedman, Norman (2004). U.S. Destroyers. Annapolis, MD: Naval Institute Press.
Gardiner, Robert; Chesneau, Roger (1980). Conway’s All the World’s Fighting Ships 1922–1946.
Hodges, Peter; Friedman, Norman, eds. (1979). Destroyer Weapons of World War 2. NIP
McComb, Dave (2010). US Destroyers 1934–1945. Long Island City, New York: Osprey Publishing.
Reilly, John (1983). United States Navy Destroyers of World War II. Blandford Press.
Rohwer, Jürgen (2005). Chronology of the War at Sea, 1939–1945: The Naval History of World War Two. NIP
Rohwer, Jürgen; Hümmelchen, Gerhard (1992). Chronology of the War at Sea 1939–1945. NIP
Roscoe, Theodore (1953). United States Destroyer Operations in World War II. NIP
Silverstone, Paul H. (1965). U.S. Warships of World War II. London: Ian Allan Ltd.

Links

https://en.wikipedia.org/wiki/Mahan-class_destroyer
http://www.navypedia.org/ships/usa/us_dd_mahan.htm
http://pwencycl.kgbudge.com/M/a/Mahan_class.htm
http://www.microworks.net/pacific/ships/destroyers/mahan.htm
http://www.tincansailors.org/ShipsStore/profiles/conf%20XX-Mahan%20as%20modified.htm
https://lcoat.tripod.com/shipdraw.htm
https://alchetron.com/USS-Cushing-%28DD-376%29
https://maritime.org/doc/plans/index.php
Full plans set on maritime.org/

Videos

Model Kits


General Query on scalemates
Unlike WW1 USN DDs, the choice of kits for the Mahan class is a bit better, but just: Let’s cite USS Conyngham DD-371 by Iron Shipwrights at 1:350, USS Mahan DD-364 1942 by MidShip Models 1:700 which also done the USS Dunlap DD-384 1938 and the Rebuilt Mahan Class USS Cassin DD-372 in 1943. There is also a 1-700-194-MHN USS Mahan 1941 by Kraken Hobbies 1:700. Model Monlay fo thos tempted by 1:72 scratch made a 5″/38 cal. “Single Knuckle” Mount, early Mk.30 single-gun mount. Model Monkey 1:72 XP Forge also made its 1:1200 for wargaming.

As for books, the USS Cushing DD-376 by Model Monkey and USS Cushing DD-376 US Navy Booklet of General Plans, official US Navy in new 2022 Digital form, as USS Flusser DD-368 US Navy Booklet of General Plans from Federal Shipbuilding, Drydock Company and naval yard for a nice large scratchbuilt base.

The Mahan class destroyers in service

US Navy ww2 USS Mahan DD-364


USS Mahan (DD-364) was commissioned on September 2, 1936, named after Rear Admiral Alfred Thayer Mahan, the prominent naval strategist, historian, naval academy professor and president. His works and legacy are still with us today.
She will be an example of career for the whole class, seen here in detail: USS Mahan was built by United Dry Docks of Staten Island, New York, he keel laid down on 12 June 1934, launched on 15 October 1935 (Christened by the admiral’s great-granddaughter), commissioned on 18 September 1936. She made the usual Caribbean initial training and shakedown touring South American ports for two months and only came back in July 1937 to Southern California, having rounded the cape. She took part in fleet training and was assigned to Pearl Harbor.

Nothing mych happened but her routine of yearly exercizes and upkeep on the Californian coast in 1937-41, while tension was mounting with Japan. Thus, she was kept to Pearl Harbor aven after the start of WW2 and transfer of many destroyers to the Atlantic for neutrality patrols. On 7 December 1941 under Commander R. W. Simpson, she was screening for task force 12 centered around USS Lexington, with three cruisers and four destroyers ferrying aircraft to reinforce Midway Island. Soon after they were dispatched TF 12 was asked to search for the Japanese and after failing to find them, were back in Pearl on 12 December.

Later in December, Mahan was detached with 103 Marines aboard landed on Johnston Island (about 750 nm west of Hawaii) while evacuating 47 natives and residents to Hawaii. Next Mahan was sent to escort a convoy to Samoa with Task Force 17 (USS Yorktown). TF 17 also raided Jaluit Atoll, Mili Atoll and Makin Atoll (Marshall-Gilberts). USS Mahan was off Canton Island by late February 1942 for patrol. In early April she escorted a Pearl Harbor convoy back to for San Pedro in California. She was directed to Mare Island Naval Shipyard for her first major wartime overhaul on the 18th.

Battle of Santa Cruz Islands
Back in Pearl Harbor in August 1942, after patrolling these waters by mid-October she was assigned Task Force 16 (USS Enterprise) also comprising USS South Dakota, two cruisers and seven destroyers. They were soon amalgamated with TF 17 (USS Hornet) as Task Force 61 (RADM Thomas C. Kinkaid) sent to Santa Cruz Islands to prevent the invasion of Guadalcanal.

On 26 October, Enterprise’s search planes spotted and attacked IJN Zuiho starting the Battle of the Santa Cruz Islands in motion. This first air-sea battle ended a bit as pyrrhic, but the screening destroyers, including Mahan, put up a fierce AA defence and were commended for their effort. Next, Mahan was sent with the fleet to Noumea, New Caledonia. On 27 October while underway a Japanese submarine was detacted and the convoy took evasive action but when it happened, USS Mahan and South Dakota collided, with quite extensive damage. She received temporary repairs at Noumea enough to proceed to Pearl Harbor where she received a new bow.

New Guinea Campaign
On 9 January 1943 she was back in action in the South Pacific, escorting convoys between the New Hebrides and Fiji while based off New Caledonia for the Guadalcanal Campaign. She visited and operated in Australian waters and in August she was based in Milne Bay, New Guinea. In August 1943, under Lieutenant Commander James T. Smith she was part of a strike on Lae, with three other US destroyers, bombarding Japanese installations at Finschhafen. The Lae Task Force (RADM Daniel E. Barbey) left Milne Bay for Lae with 8,000 Australian troops and landed them up to 4 September. On the 11th Salamaua and on the 16th Lae were recaptured, Mahan covering the landings and patrolling the area.

On 21 September she escorted another force from Buna, and carried an Australian infantry brigade herself. On the 22th, she was part of the attack on Finschhafen and soon withdrawed from the area when ten Japanese torpedo planes attacked. Theor combined AA fire downed eight of the ten. On 14 December 1943 she left Buna again to take part in the landing at Arawe in New Britain. She was part of the bombardment with four other destroyers. The force arrived off Arawe on the 15th, proceeded to the bombardement, forcing the Japanese to retreat.

On Christmas 1943 Mahan was sailing to Borgen Bay (Cape Gloucester, New Britain), meeting uncharted waters and with USS Flusser she was sent to sound out the channel. Two minesweepers layed buoys to create a path. On 26th, the Marines landed, and the afternoon the force repelled an attack. Later in February 1944, Mahan was assigned the 7th Flee covering a landing at Los Negros Island (Admiralty). However in March she was sent home for another overhaul at Mare Island Naval Shipyard, with extensive modifications. She left in July 1944 for Pearl Harbor and after refreshing exercises until 15 August she was sent to New Guinea on 20 October via Eniwetok, Jaluit, Guam, Saipan and Ulithi and escorting convoys towards Leyte. By late November 1944, she was patrolling Leyte waters.

Battle of Leyte and loss
Mahan was soon assigned the amphibious attack force on Ormoc. By the morning of 7 December 1944, she escorted the troopships carrying the 77th Infantry Division until they landed and patrolled the channel between Leyte and Ponson Island. Nine Japanese bombers and four escort fighters soon arrived on the scene and attacked the force, including Mahan, soon targeted by one of the first Kamikaze attacks, after the torpedoes had been launched. USS Mahan by that time had a strong AA and managed to shoot down four attackers but soon took three direct kamikaze hits, the most serious being a hit to her superstructure, near No.2 gun, decapitating her command.
In flames, Mahan was was ordered by Commander E. G. Campbell, which survived, toward the picket line in order to save her but soon order to abandon ship. She was assisted by USS Lamson and Walke, rescuing survivors. She had six missing, 30 seriously wounded, and she had to be finished off by torpedoes and gunfire. Her captain praised how his crew managed with the situation. She would receive received five battle stars for her service.


⚠ NOTE: The following career records has been generated using ChatGPT as a test. Enjoy (grin)

US Navy ww2 USS Cummings DD-365


USS Cummings (DD-365) was commissioned on April 28, 1936, named after Andrew Boyd Cummings, a naval officer who served during the Spanish-American War and World War I.
During World War II, Cummings served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign and the Battle of Leyte Gulf.
In 1945, Cummings was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 11 battle stars for her service during World War II.
After the war, Cummings served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Drayton DD-366


USS Drayton (DD-366) was commissioned on October 9, 1936. She was named after Percival Drayton, a naval officer who served during the American Civil War.
During World War II, Drayton served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, and the Battle of the Eastern Solomons. She also took part in the Aleutian Islands campaign and the Battle of Leyte Gulf.
In 1945, Drayton was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 12 battle stars for her service during World War II.
After the war, Drayton served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Lamson DD-367

uss lamson
USS Lamson (DD-367) was commissioned on November 20, 1936. She was named after Roswell H. Lamson, a naval officer who served during the American Civil War and the Spanish-American War.
During World War II, Lamson served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of Leyte Gulf, and the Battle of Okinawa.
In 1945, Lamson was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 11 battle stars for her service during World War II.
After the war, Lamson served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Flusser DD-368


USS Flusser (DD-368) was commissioned on November 2, 1936. She was named after Charles W. Flusser, a naval officer who served during the American Civil War.
During World War II, Flusser served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of Leyte Gulf, and the Battle of Okinawa.
In 1945, Flusser was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 11 battle stars for her service during World War II.
After the war, Flusser served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Reid DD-369


USS Reid (DD-369) was commissioned on December 30, 1936. She was named after Samuel Chester Reid, a naval officer who served during the War of 1812.
During World War II, Reid served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of Leyte Gulf, and the Battle of Okinawa.
In 1945, Reid was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 13 battle stars for her service during World War II.
After the war, Reid served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Case DD-370


USS Case (DD-370) was commissioned on March 8, 1937. She was named after Augustus Ludlow Case, a naval officer who served during the American Civil War.
During World War II, Case served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of Leyte Gulf, and the Battle of Okinawa.
In 1945, Case was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 11 battle stars for her service during World War II.
After the war, Case served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Conyngham DD-371


USS Conyngham (DD-371) was commissioned on March 19, 1937. She was named after Gustavus Conyngham, a naval officer who served during the American Revolutionary War.
During World War II, Conyngham served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of Leyte Gulf, and the Battle of Okinawa.
In 1945, Conyngham was assigned to the Atlantic Fleet and participated in the invasion of southern France. She earned 13 battle stars for her service during World War II.
After the war, Conyngham served as a training ship and was eventually decommissioned in 1947. She was sold for scrap in 1948.

US Navy ww2 USS Cassin DD-372


USS Cassin (DD-372) was commissioned on April 21, 1937. She was named after Stephen Cassin, a naval officer who served during the War of 1812.
During World War II, Cassin served in the Atlantic theater, participating in the Neutrality Patrol, the invasion of North Africa, the invasion of Sicily, and the invasion of Italy. She also took part in the Normandy landings and the invasion of southern France.
Cassin was heavily damaged during the Normandy landings when she was hit by a German shore battery. She was repaired and returned to service in 1944. She earned six battle stars for her service during World War II.
After the war, Cassin served as a training ship and was eventually decommissioned in 1946.

US Navy ww2 USS Shaw DD-373


USS Shaw (DD-373) was commissioned on September 3, 1936. She was named after John Shaw, a naval officer who served during the Barbary Wars.
During World War II, Shaw served in the Pacific theater, participating in the Battle of Midway, the Guadalcanal campaign, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of the Philippine Sea, and the Battle of Leyte Gulf.
On December 7, 1941, Shaw was moored at Pearl Harbor when the Japanese launched a surprise attack on the base. She was hit by three bombs and her forward magazine exploded, causing extensive damage. Despite the damage, Shaw was repaired and returned to service in 1942.
Shaw earned six battle stars for her service during World War II. After the war, she was decommissioned in 1945 and sold for scrap in 1946.

US Navy ww2 USS Tucker DD-374


USS Tucker (DD-374) was commissioned on August 26, 1936. She was named after Samuel Tucker, a naval officer who served during the American Revolutionary War.
During World War II, Tucker served in the Pacific theater, participating in the Guadalcanal campaign, the Battle of the Eastern Solomons, and the Battle of the Santa Cruz Islands. She also took part in the Aleutian Islands campaign, the Battle of the Philippine Sea, and the Battle of Leyte Gulf.
Tucker was awarded nine battle stars for her service during World War II. Decommissioned in 1945 she was sold for scrap in 1946.

US Navy ww2 USS Downes DD-375

uss downes sea trials
USS Downes (DD-375) was launched on May 31, 1935, and commissioned on November 24 of the same year.
During World War II, Downes served in the Pacific theater and participated in numerous campaigns, including the Battle of Midway in June 1942. On December 7, 1941, Downes was undergoing overhaul at the Pearl Harbor Navy Yard when the Japanese attacked. The ship was heavily damaged by bombs and torpedoes, and was later deemed to be beyond repair.
Downes was decommissioned on January 15, 1942, and her hulk was stripped of salvageable parts. The remnants were later used as a target for aerial bombing practice.

US Navy ww2 USS Cushing DD-376

uss cushing
USS Cushing (DD-376) was named after William Barker Cushing, a Union Navy officer who was awarded the Medal of Honor for his actions during the Civil War.

The USS Cushing was launched on November 1, 1935, and commissioned on December 19, 1936. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,940 nautical miles at a speed of 12 knots.

During World War II, the USS Cushing participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. On November 13, 1942, while on a mission to protect a convoy near Guadalcanal, the USS Cushing was hit by a torpedo fired by the Japanese submarine I-AS. The ship sank within minutes, with the loss of 77 crew members.
The USS Cushing received four battle stars for its service in World War II. In 1944, the Navy commissioned a new destroyer, USS Cushing (DD-797), which was named after the original USS Cushing.

US Navy ww2 USS Perkins DD-377

uss perkins
USS Perkins (DD-377) was named after George Hamilton Perkins, a U.S. Navy officer who served during the Spanish-American War and was later a U.S. Senator from California.

The USS Perkins was launched on December 1, 1935, and commissioned on January 20, 1937. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,940 nautical miles at a speed of 12 knots.

During World War II, the USS Perkins participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. In October 1942, the USS Perkins was part of a task force that engaged in the Battle of Cape Esperance, during which it helped sink the Japanese cruiser Furutaka.

The USS Perkins also participated in the battles of Santa Cruz and Tassafaronga, and provided gunfire support for the landings on Bougainville, the Marianas, and the Philippines. The ship was awarded five battle stars for its service in World War II.
After the war, the USS Perkins was decommissioned on December 3, 1945, and sold for scrap on December 19, 1946.

US Navy ww2 USS Smith DD-378


Off Mare Island Naval Shipyard, 12 June 1944
USS Smith (DD-378) was named after Joseph W. Smith, a U.S. Navy officer who served during the Spanish-American War and was later awarded the Medal of Honor for his actions during the Boxer Rebellion in China.

The USS Smith was launched on February 10, 1936, and commissioned on August 25, 1936. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,940 nautical miles at a speed of 12 knots.

During World War II, the USS Smith participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. In October 1942, the USS Smith was part of a task force that engaged in the Battle of Cape Esperance, during which it helped sink the Japanese cruiser Furutaka.

The USS Smith also participated in the battles of Santa Cruz, Tassafaronga, and the Philippine Sea. It was awarded six battle stars for its service in World War II.
After the war, the USS Smith was decommissioned on December 16, 1945, and sold for scrap on December 19, 1946.

US Navy ww2 USS Preston DD-379


USS Preston (DD-379) was named after Samuel W. Preston, a U.S. Navy officer who served during the Mexican-American War and was later the Superintendent of the United States Naval Academy.

The USS Preston was launched on April 4, 1936, and commissioned on September 22, 1936. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,940 nautical miles at a speed of 12 knots.

During World War II, the USS Preston participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. In October 1942, the USS Preston was part of a task force that engaged in the Battle of Cape Esperance, during which it helped sink the Japanese cruiser Furutaka.

The USS Preston also participated in the battles of Santa Cruz, Tassafaronga, and the Philippine Sea. It was awarded six battle stars for its service in World War II.
After the war, the USS Preston was decommissioned on December 16, 1945, and sold for scrap on December 19, 1946.

US Navy ww2 USS Dunlap DD-384


USS Dunlap (DD-384) was named after Robert Dunlap, a U.S. Navy officer who served during the Spanish-American War and was later the commander of the gunboat USS Petrel during the Philippine-American War.
The USS Dunlap was launched on December 27, 1934, and commissioned on March 25, 1936. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,500 nautical miles at a speed of 12 knots.

During World War II, the USS Dunlap participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. In October 1942, the USS Dunlap was part of a task force that engaged in the Battle of Cape Esperance, during which it helped sink the Japanese cruiser Furutaka.

The USS Dunlap also participated in the battles of Santa Cruz, Tassafaronga, and the Philippine Sea. It was awarded nine battle stars for its service in World War II.
After the war, the USS Dunlap was decommissioned on November 25, 1945, and sold for scrap on January 22, 1948.

US Navy ww2 USS Fanning DD-385


USS Fanning (DD-385) was named after Nathaniel Fanning, a U.S. Navy officer who served during the American Revolutionary War and was captured by the British.
The USS Fanning was launched on October 15, 1934, and commissioned on March 15, 1936. It was armed with five 5-inch guns, four .50-caliber machine guns, and eight 21-inch torpedo tubes. The ship had a top speed of 36.5 knots and a range of 6,500 nautical miles at a speed of 12 knots.

During World War II, the USS Fanning participated in numerous operations in the Pacific Theater, including the Battle of Midway, the Guadalcanal Campaign, and the Battle of the Eastern Solomons. In October 1942, the USS Fanning was part of a task force that engaged in the Battle of Cape Esperance, during which it helped sink the Japanese cruiser Furutaka.

The USS Fanning also participated in the battles of Santa Cruz, Tassafaronga, and the Philippine Sea. It was awarded nine battle stars for its service in World War II.
After the war, the USS Fanning was decommissioned on November 25, 1945, and sold for scrap on January 22, 1948.

O Brien class destroyers (1914)

O’Brien class destroyers (1914)

US Navy ww2 USN Fleet Destroyers (1913-1936): USS O’Brien, Nicholson, Winslow, Mc Dougal, Cushing, Ericsson (DD-51-56)

US WW1 Destroyers
Bainbridge | Truxtun | Smith | Paulding | Cassin | O'Brien | Tucker | Sampson | Caldwell | Wickes | Clemson

The third “1000 tonners”, heavy on torpedoes

The O’Brien class comprised just six ships, third of five classes of “thousand tonners” based on their average 1,016 t displacement. The design was a continuation of previous Cassin/Aylwin, coming from discussions between the General Board of the Admiralty and Bureau of Ordnance (BuOrd) which proposed new torpedoes. Thus the O’Brien were more than a simple incremental development as being the first USN destroyers sporting the much larger 21 inches (533 mm) torpedoes. The design was repeated on the Tucker class and pushed further with the Sampsons, the last “thousand tonners”.


Closeup of the bridge and crew, DD-52 (USS Nicholson)

Design Development

Six destroyers were planned For the 1913 fiscal year (FY1913) and the General Board determined that six destroyers would be authorized with some limited innovations. They were simply called at first the “DD 51 class” and later the name from the lead ship was chosen, as O’Brien class.

A simple repeat of the FY1912 Cassin-Aylwin was ordered but the chief of BuOrd suggested that these new destroyers could be equipped with ten torpedo tubes and the new 21-inch (533 mm) just adopted. The General Board agreed, but in principle, waiting to recalculate weight distribution. The adoption of the new caliber indeed caused stability issues. In fact BuOrd’s centerline torpedo tubes idea was refused. The same distribution as the previous destroyers and just eight tubes seemed optimal.
The additional weight of the new torpedoes indeed, 5 long tons (5.1 t), around 50 tons with the tubes, forced a reduction of the planned two aft-facing guns for example. It was reduced to a single one forward, resulting in four 4-inch (102 mm) guns in the end. This design was approved on 20 August 1912, authorized by Congress on 4 March 1913.

Construction and Service

The six ships were laid down in four shipbuilders: William Cramp (three), and Fore River, Bath Iron Works, New York Shipbuilding Corp. one each. Keels were laid down between July and November 1913, starting with USS McDougal. But DD-51 was O’Brien and thus, became the class lead ship and namesake. USS Ericsson was the last laid down, and they were launched between April 1915 and January 1915, USS Winslow being the last completed, McDougal the first commissioned in June 1914 and the last in August 1915, USS Cushing being the last commissioned. Total cost for the hull and machinery was $790,000 of the time.

These six destroyers operated in the Atlantic and Caribbean. From April 1917, they were sent overseas, based, like most 800 and 1000 tonners, to Queenstown in Ireland, for dull convoy escort duties until the end of the war. This was mostly uneventful, between false alerts, spottings and rare attacks, and crew’s rescues as ships were routinely sunk by U-boats. At last the class had some visctories: USS Nicholson helped sink U-58 (November 1917) which happened to be the first U-boat sunk by the U.S. Navy. All were back home in January 1919, decommissioned by June 1922. But in 1924, two, USS Ericsson and McDougal were recommissioned with the United States Coast Guard for the “Rum Patrol”. Back with the US in 1932-1933, they were all sold by June 1936 after being in long reserve, ad seeing little service.

Design of the class

The O’Brien class were about the same length as the previous classes, with median displacements around 1,020–1,050 long tons (1,040–1,070 t). The next Tucker and Sampsons would just gain 10 feet (3.0 m) in overall lenght and reach 1,090–1,100 long tons. The armament of four 4-inch (102 mm) guns was similar, but the torpedo armament grew and complement also. The new 21-inches twin torpedo tubes benefited from eight reload torpedoes, like the following two. The new Mark 8 torpedoes were largely untested at the time, but truly successful, a far cry from the trouble-ridden Mark XIV of 1941. They had not secondary artillery nor anti-aircraft guns. Only the next classes adopted a pair of 1-pdr (0.45 kg) guns or 37 mm (1.46 in).

Hull and general design

The O’Brien-class were 305 feet 5 inches (93.09 m) overall long (as the former Cassin/Aylwin), but a tad larger at 31 feet 2 inches (9.50 m vs. 9.25m) and with a standard draft of 9 feet 6 inches (2.90 m), here again, more than the Cassins (9.25 m). They had however the very same lines, with a high forecastle and recesses for the two side main guns of the main deck. They displaced between 1,020 and 1,090 long tons, with an average 1,050 long tons (1,070 t), not that heavy compared to the previous Cassins (1,036 tons/1,165 tons FL) despite their armament upgrade.

Powerplant

The O’Brien class had all two propeller shafts, two direct-drive Zoelly steam turbines, fed by four White-Forster boilers. However they divered in their auxiliary powerplants: Indeed, they diverged depending on their shipyard’s partnerships and subcontractors. Their main powerplant generated on average 17,000 shaft horsepower (13,000 kW) enabling a top speed of 29 knots (54 km/h). But these turbines were known inefficient at low speeds. So they were equipped with additional classic VTE cruising engines for under 15 knots (28 km/h). All except Cushing had these triple-expansion reciprocating engines, a pair for O’Brien, Nicholson, and Winslow, McDougal and Ericsson just one one. Cushing instead was given two more low pressure geared steam turbines. Here is the differences To resume in detail:
DD51-53: Two Zoelly steam turbines and two 2 VTE for cruising plus 4 White-Forster boilers
DD54 and DD56: Two Zoelly steam turbines and a single VTE for cruising, 4 White-Forster boilers
DD55: Two Zoelly steam turbines and two steam turbines for cruising, 4 White-Forster boilers.

Armament

Main: Four 4 in (102 mm)/50 caliber guns

Firing the 4-in gun
Firing the 4-in gun.

The serie started with the Mark 7 (1898), first used as secondary guns on the Arkansas class monitors. The Mark 8 were an improved version designed from 1905, but they gave apparently little satisfaction and were reworked from 1910, ending with threat standard Mark 9. Its general performances were such that it became also an allied standard with more than 400 transferred to the British. They were still in service in WW2 on a large quantity of ships by the way.
It was light weight and thus easy to handle, fast-firing, fast revolving and traversing.
These four 4-inch (100 mm)/50 Mark 9 guns weighing each more than 6,100 pounds (2,800 kg). They carried fired 33-pound (15 kg) armor-piercing (AP) shells exiting the barrel at 2,900 feet per second (880 m/s), reaching a target up to 15,920 yards (14,560 m) at 20° (max) elevation.
More on navweaps.com

Torpedoes

The ships had four torpedo tubes placed by pairs along the sides, along the hull amidships.
The initial model planned in 1913 was the recently introduced Bliss-Leavitt 21″ (53.3 cm) Mark 3. But when completed in 1915, they could swap on the Mark 8, really tailored for destroyer use, faster and heavier, and the first 21″ x 21′ (53.3 cm x 6.5 m) USN torpedoes. The latter had the following caracteristics:
Mods 0, 1, 2 or 2A: 2,761 lbs. (1,252 kg), 248 in (6.299 m) long, 321 lbs. (146 kg) TNT charge, settings 10,000 or 12,500 yards (9,140 or 11,430 m) at 27 knots. Powered by Wet-heater and guided by a Mark 8 Mod 1 gyro.

Depth Charges

In 1917-1918 to perform better as ASW ships, the class was equipped with two depht charge racks (DCR) and a single thrower or DCT, which was the “Y-gun”, called that way before its shape. It throwed two depht-charges at once.
The latter were probably of the Mark I type (1916) weighting 100 lbs. (45 kg) with a 50 lbs. (23 kg) wet gun-cotton exploser ad two settings, 25 and 100 feet (8 – 30 m).

Mines

The General Board called for two anti-aircraft guns and provisions for laying up to 36 floating mines but it seems the recommendations were not followed. AA guns were first integrated to the next classes, and apparently not the mines. These destroyers never used this capability anyway.


USS O’Brien, Queenstown, Ireland 1918. She is the only one which camouflage has been photographed.

⚙ O’Brien class specifications

Displacement 1,050 long tons normal, 1,171 long tons FL
Dimensions 305 ft 5 in x 31 ft 2 in x 10 ft (93.09 x 9.50 x 2.90/3.23 m)
Propulsion 2 shafts DD Zoelly steam turbines, 2 VTE, 4 White-Forster boilers 17,000 shp (13,000 kW)
Speed 29 knots (54 km/h)
Range 300+ long tons oil, 4,500 nmi () at 16 kn
Armament 4× 4-in/50 guns, 4×2 21-in TTs (16), DCR, DCT, Mines, see notes
Crew 101

Read More

Books

Bauer, K. Jack; Roberts, Stephen S. (1991). Register of Ships of the USN, 1775–1990: Major Combatants. Greenwood Press.
Friedman, Norman (2004). US Destroyers: An Illustrated Design History (Revised ed.). NIP
Gardiner, Robert; Gray, Randal (1985). Conway’s All the World’s Fighting Ships 1906–1921
Silverstone, Paul H. (1970). U.S. Warships of World War I. London: Ian Allan.
Cashman, Sean Dennis (1988). America in the Age of the Titans: The Progressive Era and World War I. New York: New York University Press.
Naval History & Heritage Command. Dictionary of American Naval Fighting Ships. Navy Department, Naval History and Heritage Command.
Osborne, Eric W. (June 2005). Tucker, Spencer C (ed.). Destroyers: An Illustrated History of Their Impact. Weapons and Warfare Series. Santa Barbara
Sweetman, Jack (1984). American Naval History: An Illustrated Chronology of the U.S. Navy and Marine Corps, 1775–Present. Annapolis, Maryland NIP
Silverstone, Paul H., U.S. Warships of World War I

Links

www.destroyers.org/tcs-ships/early-destroyer-history
destroyerhistory.org the 1000 tonners
On historyofwar.org/
destroyerhistory.org/early/flivvers
navsource.org
On navypedia.org/
Navweaps 4″/50 (10.2 cm) Marks 7, 8, 9 and 10
navweaps.com ww1 us torpedoes
on wikipedia.org
https://destroyerhistory.org: o’brien class
destroyerhistory.org/early/ussfanning
historyofwar.org

Model Kits

None found so far. Note a popular subject…

US Navy ww2 O’Brien (DD-51)

uss o brien razzle dazzle
USS O’Brien (DD-51) was built at William Cramp & Sons, Philadelphia, started in September 1913, launched in July 1914, second USN vessel named in honor of Jeremiah O’Brien and his five brothers which captured on the sloop Unity, a British warship, during the American Revolutionary War.
Commissioned in May 1915 O’brien made the usual Caribbean-east coast training and shakedown cruiser. She was dispatched to rescue the survivors of U-53 off the Lightship Nantucket in October 1916. From April 1917, she was based in Queenstown, Ireland. She made several spottings and attacks, several rescue until the end of te war and was moved to Brest in December 1918. She left in January 1919, but became a picket ship for the NC-type seaplanes trying to cross Atlantic. Decommissioned in Philadelphia by June 1922, she was neverer reactivated as stricken by March 1935 and sold for BU the next months. This scrapping was linked to the Washington treaty tonnage limitations.

US Navy ww2 USS Nicholson (DD-52)

uss nicholson prewar
USS Nicholson was built at William Cramp & Sons, named in honor of 1812 and Civil War brothers.
Commissioned in April 1915 she left the east coast and saied to the Caribbean, trained and took part in neutrality patrols. From April 1917, she was prepared in NyC for overseas service and sent to the Irish Sea patrol from Queenstown. In October 1917, she rescued SS J. L. Luckenbach attacked by U-62, repelled. The latter tried to sink the cargo by gunfire, being apparently short of torpedoes, for three hours when the destroyer arrived. In November, Nicholson Fanning, spotted, tracked and sank U-58, first USN “kill”. In September 1918, Nicholson drove off U-82 after the latter torpedoed Vernon off France.
Back home, she was in reduced commission by November 1919, decommissioned at Philadelphia in May 1922. Stickern in January 1936 she was sold for BU in June the same year.

US Navy ww2 USS Winslow (DD-53)

USS Winslow in sea trials 1915
USS Winslow in sea trials 1915
USS Winslow was another Cramp destroyer (commemorating John Ancrum Winslow, which sank CSS Alabama), commissioned by August 1915; She made her shakedown in the Caribbean and trained on the east coast. She was also sent to rescue suvivors of U-53 in late 1916. From April 1917, she was sent to patrol the Irish Sea and esecorts. She took part in several unsuccessful U-boats hunts, and rescued survivors of many vessels.
Back home in 1919, she was placed in reduced commission by December 1919, decommissioned at Philadelphia in June 1922 (and seeing limited service on the east coast in between). In November she was renamed “DD-53” to free her name and stricken in January 1936, sold in June.

US Navy ww2 USS McDougal (DD-54)

uss mcdougale date unknown
USS McDougal was from Bath Iron Works in Maine (named after David Stockton McDougal, which fought in a 1863 battle off Japan on USS Wyoming), commissioned in June 1914.

She underwent the same routine off the east coast and Caribbean as her sisters, then neutraliy patrols, and was one of the five destroyers sent to rescue survivors of U-53, having aboard 6 crewmen from a sunken Dutch cargo. From April 1917 she was prepared for overseas service and based in Queenstown. She made several unsuccessful attacks on U-boats and rescued survivors. She collided with a British cargo in February 1918, and was repaired until 20 July before being transferred to Brest in France to escort repatriation convoys from November-December.

Back home in early 1919 she resumed operations with the Atlantic Fleet, until August 1919, in reserve, reactivated for little service in mid-1921, then reserve and decommission in Philadelphia by May 1922. By June 1924, she was reactivated after modifications to serve with the Coast Guard’s “Rum Patrol” as USCGC McDougal (CG-6) until May 1933. Renamed “USS DD-54” back in USN, she was stricken in July 1934, sold in August.

US Navy ww2 USS Cushing (DD-55)

USS Cushing, 1915 sea trials
USS Cushing, 1915 sea trials
USS Cushing was built at Fore River Shipbuilding (Quincy, Massachusetts), named about the captain which sank the Confederate ironclad warship CSS Albemarle. Commissioned in August 1915 she alternated her peactime service between the east coast and Caribbean, was dispatched for the survivors of U-53 in late 1916 and was prepared from April 1917, to join the USN DD based in Queenstown. She made many escort missions, several unsuccessful attacks, rescued survivors, was transferred to Brest late 1918, and back home in January 1919, seeing part-reserve and limited commission until decommissioned at Philadelphia in August 1920, never reactivated and stricken in January 1936, sold for BU.

US Navy ww2 USS Ericsson (DD-56)

USS Ericsson as coast guard ship CG-5, Rum Patrol, 1930
USS Ericsson as coast guard ship CG-5, Rum Patrol, 1930
USS Ericsson was built at New York Shipbuilding, Camden, NYC, (named after Swedish-born builder of USS Monitor), commissioned relatively late, in May 1916, and alternating between the east coast and Caribbean, followed by neutrality patrols, and the rescue or survivors from U-53, carrrying 81 passengers from a sunken British ocean liner to Newport. From April 1917 she was prepared for overseas service and one of the first to arrive in Queenstown. Like many DDs of her class, she spotted and made several attacks on U-boats, and rescued survivors.
Back home in 1919, she resumed Atlantic Fleet service until August, and was placed in reserve, and then limited commission, seeing some operaions in 1921, and redecommissioned in Philadelphia, June 1922. She also served with the United States Coast Guard as part of the “Rum Patrol”, pennant CG-5, until May 1932. Discarded in early 1934 she was sold in August.