Sverige class (1915)

Sweden’s last Pansarkepp

Sweden’s very last coastal battleships is a saga out of itself. Largest ships ever built in Sweden before even the Great War broke out, completed after many delays in 1917, 21 and 22, they became the flagships of the coastal defence until faster, more modern cruisers (The Tre Kronor class) were chosen for the task of leading the three resident naval forces of the country. Largely funded by popular support, these three vessel looked superficially like regular-pre-dreadnoughts, but were every bit tailored for the need of Svenska Marinen.
By size and tonnage they dwarved everything built before, notably 1906 Oskar II. They would have a very long career, as customary in the Swedish Navy, being rebuilt and modernized to face WW2 and a large part of the Cold War, although completely obsolete by that time and relegated since a long time to secondary duties.

Design Development

Rendition of the future Sverige in 1912 during the fundraising campaign, now at the Sjöhistoriska museet

Sweden witnessed the naval arms race after dissolving the union with Norway in 1905, tensions rose again with the Russian Empire, Germany, and Norway and by 1911, their ships were cruising around in the North Sea. In these circumstances, the Swedish Government only avalized the construction of Oscar II, a typical pre-dreadnought but with 8-inch guns for 17.8 knots and she was found totally inadequate, especially after the launch of HMD Dreadnought, likely to be followed by other nations.
The admiralty pushed fir a new class with extra seaworthiness, better armament, better protection and extra speed, and with the latest technologies, notably in fire control. In 1911, with the dreadnought race ongoing, the parliament voted at a small majority funds for the “F-boat” program the last of all proposals prepared and examined, A, B, C, D, D1, D2, E, E1, E2 and F, ranging from 4,800 to 7,500 metric tons and with various armaments and speed to match.

The Sverige-class coastal battleships were the largest ships ever to serve in the Swedish Navy at that point. Their design was totally new and inspired by other nations’ own dreadnought designs. Their armament was head and shoulders above the previous Oscar II (see below) with four 283 mm (11 in)/45 cal.
Bofors guns in twin turrets (rather than two 210 mm in single turrets) and eight 152 mm (6 in) Bofors guns a single superfiring twin turret and six single broadside made her battery. Just one on three of the Pansarkepp was ready on time to serve at the end of WW1 but all three formed the backbone of the Swedish Navy during WW2, next interwar constructions revolving around cruisers, destroyers, and submersibles.

Enhanced swerige-class coastal battleship project, before the post-war ban of new constructions: She would have been armed with six 305 mm in twin turrets and six single 105 mm guns.

The Sverige-class was a new take on the coastal Defence ship, with an heavier armament, better speed, and armor. But still, the hull was tailored not for high seas but for local archipelagos and shallow waters. Their tactical doctrine and operations were also new. Indeed they formed the core of an open-sea battle group (which should have originally comprised four and not three ships), and were meant to operate with cruisers, destroyers, torpedo boats, but also air reconnaissance. This small battle group was to operate as a defensive force only.

Construction

Painting at the Sjohistoriska museet
“Sverige” (“Sweden”) was initially decided in 1911 to start the type F, submitted by the Admiralty, approved by the parliament. She was properly funded and voted. However, there was a change of government the next year. The new liberal majority prime minister Karl Staaff decided against new military spendings and against this ship. Thus, the project was postponed until an exhaustive analysis took place, before motivating any further decision.
However soon, a national move (parlty helped by a critical press and fuelled by international nationalism) a campaign was quickly setup to raise more money. In total, over 15 million crowns were gathered, and this helped the ship to be voted in 1911 (under a price bill of 12 million). This law was called the “Pansarbåtinsamlingen”. Breween the press, popular optinion, the parliament and funding, the government was cornered to authorize construction. The ship was also called called “the people’s gift to the country”.

The two next were voted in 1914 by the same government, now with a war to motivate it. These were called HMS Drottning Victoria and Gustav V. Both were laid down in 1915 due to material shortages, launched in September 1917 and January 1918 respectively. The war ended before any could be operational, but fortunately the country never left its neutrality stance. Both last vessels were completed in 1921 and 1922, modified with the experience from Sverige and modified in the interwar during completion.

Design of the Sverige class

Brassey’s Naval annual armour scheme of the class, 1923

Hull and general design

The hull was 120 meters long (390 ft) for a 6,852 tons standard displacement which rose to 7,516 tons fully loaded for HSwMS Sverige, of another level also compared to Oscar II. Probably in 1914 they were the meanest coastal ship in any navy of the time, worthy of a “pocket dreadnought”. Other sources gives 6,961 tonnes tons standard, 7,758 tons deep load for Sverige initially.
With reconstruction and additions in WW2 they rose to 7,239 tonnes standard, 7,755 tonnes full load.
As for dimensions, her two sister ships were slightly different, at 121.6 m (399 ft) long, but the rest was the same at 18.6 m (61 ft) in beam and 6.2 m (20 ft) in draught but 6.3 m (21 ft) for Sverige.

Armour protection layout

Armor scheme included the following:
-200 mm (7.9 in) thick belt, central section tapered down to 100 mm (3.9 in) and 60 mm (2.4 in) both ends
-Upper belt 100 mm (3.9 in) behind fore barbette and aft barbettes.
-Main turret 200 mm (7.9 in) front, 100 mm (3.9 in) sides, 50 mm (2.0 in) roof.
-Main Barbettes 150 mm (5.9 in) above the ammo wells,
-Secondary turrets 125 mm (4.9 in), 100 mm (3.9 in) barbettes.
-Forward conning Tower 175 mm (6.9 in)
-Armor decks ranged from 45 to 30 mm (1.8 to 1.2 in).
All in all it was 50 mm more for all figures compared to Oscar II, sufficient to deal against Armoured cruisers of the time, but a bit light to face contemporary battleships.

Powerplant

Engine telegraph on Drotting Victoria
To propel these 7,000 tons monsters, the machinery comprised four shafts coupled to Curtis turbines rated for 20,000 SHP total and 12 Yarrow-type coal-fired boilers. This figure was for the Sverige only. The two others had Westinghouse geared turbines rated for 22,000 SHP and were upgraded in the interwar to oil-fired models. The Westinghouse geared turbines manufactured by Motala Company for Gustaf V and Drottning Victoria, and rated for 22,000 SHP.
As for the range, Sverige carried initially 776 tons of coal, and later was added 100 tonnes of oil and it was 761 tons for the two sister ships (same for oil).

Armament

The armament comprised four 283 mm (11 in) 45 cal. Bofors that were equivalent to the German main battleship caliber of the time. The rate of fire was good at 17 sec. between shots but the turrets were rather cramped because of the partition between guns inside both turrets. The eight 6-in/50 caliber QF guns in twin and single turrets were rather a modern arrangement, more than usual broadside barbettes.

Main

The Bofors 28.3 cm/45 (11.1″) Model 1912 were designed from 1912 for the Sverige class, and in service by 1917. Further projects of Pansarkepp were never followed-up in the interwar so they were the last. These guns were of built-up construction, with a hand-operated screw breech-block of the typical ogival type. They had a rather high rate of fire for the time (3-4 rounds per minute) and were considered to be quite accurate, making the ships quite a deterrent indeed for any capital ship.
In the 1930s a new and more aerodynamic “Arrow Nose Shell” was developed for increased range and compensate for the apparition of new, larger guns, notably in Germany the Schanrhorst’s 28 cm SK C/34 naval guns which had a 40,930 m (44,760 yd) at 40° elevation.
One of these guns (from Drottning Victoria) was preserved, now at the Karlskrona Naval Base.
They weighted 43.4 tons (44.1 mt) for a barrel lenght of 501.4 in (12.735 m), bore alone 484.1 in (12.295 m) and rifling of 414.0 in (10.515 m), 80 grooves.
They fired a Bagged type projectiles, 672.4 lbs. (305 kg) AP shells with a 220.5 lbs. (100 kg) charge.

Muzzle Velocity was 2,854 fps (870 mps), enabling a range of 21,435 yards (19,600 m)/18° later ported with the 672.4 lbs. (305 kg) Arrow Nose shell to 31,700 yards (29,000 m) at 25°, after gun cradle modifications. The penetration at 6,560 yards (6,000 m) was 350 mm of hardened KC steel at 0° (13.77 in) and at 19,690 yards (18,000 m) 155 mm (6 in) down to 87 mm (3.4 in) on a horizontal armor. The 350 tonnes turret elevated initially to 18°, later to 25, at 5° per second and traversed at 4°. Gun axes were about 83 in (210 cm) apart to avoid interference.

Secondary

These eight 152 mm (6 in)/50 cal. guns were placed in a single twin turret forward, superfiring above the main 11-in forward turret, and six single mounts in single turrets, not unlike the British 1906 Lord Nelson class pre-dreadnoughts.
These 15.2 cm/50 (6″) Model 1912 were unique to the Sverige class. They were rather similar to the earlier Model 1903, used a hand-operated screw breech-block (ogival type).
In short, these 7.63 tons guns had a bore lenght of circa 300 in (7.620 m) and fired like the main guns at 3-4 rounds per minute.
They used a bagged AP 101 lbs. (46 kg) shell at 2,789 fps (850 mps) up to 15,000 yards (13,716 m) at 30° elevation.
Some ended after WW2 as land artillery, notably at the top secret “Kalix line” (northern Sweden), near Vuollerim in service until the 1990s amazingly. The fort was turned into a museum.

Tertiary

In addition, four 75 mm (3 in) Bofors AA cannons were mounted forward of the rear turret. No infos on these, even on the excellent navweaps.com.
There were also two anti-ship QF 57 mm (2.2 in) short-barreled Bofors and nine 6.5 mm (0.26 in) Machine-Guns
As customary for the time, the armament was rounded to two 457 mm (18 in) torpedo tubes.

Reconstructions and modernizations

Sverige in 1929, before her major reconstruction
During WW2 this doctrine was still active and indeed they offered a smaller target to submarines, torpedo crafts or dive-bombers and minefields, some authors suggested they were taken in consideration in the decision by the Germans high command in WW2 not to invade Sweden in 1940. In fact, Jane’s 1938 edition classed these ships as battleships due to their use in a coherent battle group.

Machinery

The 12 Yarrow boilers were later upgraded to oil-fired boilers in the 1930s on Sverige, but not on Gustaf V and Drottning Victoria for strategic reasons. It was decided to keep the ability to burn coal if Swedish oil supply was cut off. Also after reconstruction they started to diverged widely in appearance:
Gustav V had funnels trunked into a single one, upper works well modified.
Sverige had her fore funnel trunked back away from the superstructure (also modified) but kept the second funnel.

Armament Upgrades

-The underwater torpedo tubes were removed and the room was converted into an artillery central, feeding data from modern range meters, coupled with new fire control systems for the heavy, secondary and AA-gunnery
-Small guns and two 6 in guns were removed. Modern Bofors 75mm, 40mm and 20mm AA guns were installed instead.
-Gustav V had her forward superfiring twin 152 mm (6 in) turret removed but a gyro-stabilized AA artillery (4×40 mm bofors) mount placed instead.
-Sverige and Drottning Victoria had their midship single 152 mm (6 in) guns removed, replaced by the same.
-Main 11 in guns range augmented, between the 25° elevation and new shells (as seen above).
-New complement reached 450, making these ships appear even more cramped. They were not popular in WW2, but still the country’s “insurance card” against a menacing Kriegsmarine.

Modernization History

Sverige in 1931, in sea trials, post reconstruction
In 1924-1926 Sverige was given a new tripod mast, new director and fire-control centre and later on Drottning Victoria, same tripod mast and director, fire-control centre and both received paravanes. Gustav V was moderned later, between 1927 and 1930. Same midifications, but with her main mast cut and moved forward, delettion of six original 75mm/49 Bofors guns and addition of two twin 75mm/56 K/60 M28 guns.
In 1931-1937 all three saw radical armametn upgrades. Sverige received machinery and funnel modifications, mast too, new Curtis geared turbines and same armament upgrade as Gustav V.
It was the same for Drottning Victoria but she had 6 Yarrow mixed-burning boilers replaced by two oil-burning Penhöet, with fuel stowage modified to 360ts of coal and 273ts of oil. In additon to the twin 75mm/56 K/60 M28 she also received three single 25mm/55 K/58 M32 AA guns.
Gustaf V completed her prewar modernization last, with 6 Yarrow mixed-burning boilers replaced by two same oil-burning Penhöet (same figures) and same armament upgrade with in addition four single 25mm/55 K/58 M32 AA guns.

Gustav V in WW2

From 1938 and until 1942 they had limited upgrades. Sverige had four oil-burning Penhöet boilers installed, lost two 152mm/49 guns for two twin 40mm/56 K/60 M32, tw twin 25mm/55 K/58 M32 AA guns, and Drottning Victoria followed suite, but with two single 25mm/55 K/58 M32 and then twi more a year later.
In 1942 all three were upgraded again. Sverige had the two twin old 25mm/55 retired and instead a single twin 40mm/56 K/60 M32 installed as well as two twin 20mm/63 K/66 M40 (Licenced Oerlikon).
Drottning Victoria had all her seven 25mm/55 retired for the same, but instead of twio twin, seven 20mm/63 K/66 M40 (they replaced the 25 mm as a one-per-one basis).
Gustaf V had initially two twin and four single (8 total) 25mm/55 and they were all retired for four single 25mm/55, the twin 40mm Bofors and two twin plus four single 20mm/63 K/66 M40 AA guns.
In 1943 Drottning Victoria was the first equipped with a Swedish-built radar and after the war Gustaf V was equipped with a British radar. Sverige never received this upgrade.