Royal Norwegian Navy in WW2

A coastal Navy with ships, fjords and forts

Everybody remembered the Norwegian Campaign. It seems at first a contest between the Kriegsmarine (which had remendous losses), and the British and French Navies. But the Norwegian Navy, despite its small size did surprisingly well, using also coastal batteries at the best of its capabilities. The Norwegian campaign of 1940 surely left Hitler a sour taste towards the surface navy for the remainder of the war.
Norway was one of the stakes of the war, with its resources (iron and other metals, coal, and heavy water for an hypothetical nuclear program) and its considerable coastline on the North Atlantic and the Arctic. A Strategic position, it became a target all the more tempting that the Royal Norwegian army was weak, as well as its navy and its aviation.

Poster of the Norwegian Royal Navy
Poster of the Royal Norwegian Navy – Based on conway’s profiles. Up: The RNN in 1940 and below the free Norwegian Navy.

Inheritance from WW1

1914-18: Neutrality sorely tested

The Royal norwegian Navy in WW1 (Sjøforsvaret) has been freed from its Union and Royal alliance with Sweden in 1905. At that time, it consisted of two 3,500 tons coastal defence ships (HNoMS Harald Haarfagre and HNoMS Tordenskjold, four ironclad monitors, three unarmored gun vessels, twelve gunboats, sixteen 60 tons gunboats, and 27 torpedo boats. Norway remained neutral during the conflict although this neutrality was tested in many occasions. Indeed its merchant fleet suffered heavy casualties to German U-Boats, but also German surface commerce raiders, especially from 1917.

During the Great War indeed, Norwegian traffic was undermined and soon the submarine “total war” of the Kaiser made no distinction between Neutral nations and others. “tricks” had been used and the tactics of false flags and Q-Ships as well as the nature of boarding controls prove untelable to the German U-Boat force. However, despite the losses, large private companies still made a profit.

Norge
Relic: The Coastal Battleship HNoMS Norge, still active in 1940.

Interwar: Anti-war sentiments keep the fleet down

Definitively a “green water navy”, the Norwegian force was not supposed to engage in long range campaigns abroad and concentrated in defending the numerous and majestuous Fjords that dotted the western coast. In 1918, the Norwegian Navy was found lacking modern ships. The British-ordered Björgvin and Nidaros were requisitioned, pressed into service after completion as HMS Glatton and Gorgon and were never delivered.

In any cases the post-Versailles treaty postponed any program as defence spending were reduced to nil. The minelayer Olav Tryggvason for example was suspended and eventually ordered in 1932. Until the, only six coastal submarines had been authorized. There were however concerns from 1933 when the Nazi Party started its rise. In 1929 already, RNN Vice Admiral Wegener in his 1929 book warned that for Germany, control and occupation of Denmark and Norway were a necessity in any future war.

hms glatton
HMS Glatton: These would have been if completed and delivered, potent coastal battleships for the RNN.

The vegetated economy of the country and the crisis of 1929 did not help securing a budget for a Navy. It was only by 1934 that plans were made for a renowal. A dramatic one. Admitted to the League of Nations in 1920, Norwegian exports grew as well as the GDP. A Norwegian became president of the League of Nations in 1939.
The 1930s saw many of the oldest vessels scrapped, meaning most of the WW1 era fleet. Many of these major warships indeed dated back the 1890s. There were few replacements, meaning in 1939, the Norwegian Naval Force consisted only of four coastal destroyers and a bunch of Torpedo Boats. More late 1930s ordered consisted in two minesweepers and two patrol crafts, while two larger destroyers were laid down. It was too late however as war broke out.

However, coastal batteries were added to those already existing at the entrance of some important fjords (Bergen, Narvik, Oslo…). These works were very far from constituting a “coastal maginot line” so much could they be turned and taken by well trained alpine commandos and paratroopers as proved the operations in Belgium against Eben Emael in 1940. Apart from 6 submersibles in 1922-29, only modern 3 torpedo boats, while three others were under construction at the beginning of the war plus two destroyers has been authorized by a frightened parliament over recent developments in Germany.

The Norwegian Navy in WW2

Available forces: The Navy

The Royal Norwegian Navy was put on high alert, despite declaring neutrality like the rest of Scandinavian in September 1939. The Navy by that time comprised:
Four old coastguard battleships: Two 1900 Norge class, two 1897 Tordenskjold class
Three Draug-class destroyers,
-Three squadrons of 26 torpedo boats plus three modern of the Sleipner class.
-Three coastal submarines (1916), six more of the B class (1923)
-Two sloops
-Three 1916 minelayers ad the Olaf Tryggvason (1931).
The latter was the only major unit adopted during the interwar.

In construction when the war broke out:
-Two Aalesund class destroyers
-Three Odin class TBs
See the second part of the post (col 2) for the precise nomenclature and ship’s history.

Norwegian Coastal Fortifications

Kristian Eriksen Oscarborg Also managed by the Navy, the Norwegian coastal forts dated back for some to the XVIth century. Modern fortresses included the Hegra Fortress, Kvarven Fort, Odderøya Fortress, Oscarsborg Fortress, and Møvik Fortress. Oskarborg faced Oslo in a large island that was like a wedge inside the fjord. It took part in the Battle of Drøbak Sound which saw the destruction of the KMS Blücher. The fortress was under orders of Kristian Eriksen (photo), armed by three German 28 cm. 1900 vintage guns in open air.

The Hegra Fortess own artillery consisted of two 7.5-cm (3.0 in) and four 10.5-cm (4.1 in) artillery pieces in half-turrets. They were buried in pits dynamited from the rock, lined with concrete. The oldest guns were four Krupp M/1887 field guns, 84 mm (3.3 in) without recoil systems. The fortress has been deactivated until 1939 and was besieged in April-May 1940.

Odderøya Fortress was responsible for defending the access to Kristansand and Arendal. On 9 April, she fired at the light cruiser Karlsruhe, three torpedo boats and seven smaller vessels plus a mothership carrying total some 1,000 infantry. The battle of Kristiansand saw the fort at first dissuading the German ships to enter while the brand new Norwegian TB HNoMS Gyller short down at least two Stukas. Air attacks on the fort rsulting in the explosion of the ammo depot. The fort however received confused orders of incoming allied ships, mistook a german signal as a french flag and did not fired. Infantry was landed and the fort was taken and surrendered later.

The 1902 Kvarven fort was manned by 33 officers and 279 corporals in 1940, housing several Howitzer L/14 cannons and the second land based torpedo battery after oskarborg. The Fort fired at the approaching cruisers Königsberg and Köln and escorts bound to Bergen. However the fort only had a few hits on two torpedo boats and the cruiser Köln due to heavy fog.

Later that day, 9 April, the KMS Bremse was hit twice, and the MTB mothership Carl Peters. Later, KMS Königsberg tried to get through and was hit trice, beneath the waterline, on deck and the conning tower, but she survived. The fort, like almost always during the campaign, surrended after being rear-assaulted by German infantry freshly landed.

28 cm gun at Oscarborg

After the occupation started, these defences were considerably improved, taking part in the Atlantic Wall as (Festung Norwegen) “Fortress Norway”. Outside the many new guns which were installed, anti-aircraft batteries, tank and infantry forces were also based there, a large percentage of the 400,000 German troops deployed in Norway during the war. The Germans built for example the Grønsvik coastal battery, Batterie Vara and Trondenes Fort (in 1942-43). The latter had 406 mm guns.

Batterie Vara
BNorth Atlantic Wall: The Batterie Vara (MAB 6./502 Vara) in cosntruction by Todt. There would be four 38 cm SK C/34 naval cannons.

Therefore Norway focused on a coastal defense policy, just like the other neutral Scandinavian countries. Mines, submarines, and coastal defences (including these old coastal ‘battleships’) were the only luxury available to delay the enemy rather than really dissuade. Until April 1940, the Norwegian Navy conducted neutrality patrols, just like in WW1. These tasks were performed by ships worthy of museum exhibitions sometimes, like the 1874-1888 small minelayers of the fleet.

Some ships were in poor conditions: The 1897 coast defence ships of the Haarfarge class had thei main guns deposed and carried to coastal artillery sites. They were anchored as static guardships during the war. Both survived it. Most of the Torpedo boats were 30 to 40 years old and were relegated to limited patrols, as long as they can be maintained properly.

The Norwegian campaign (April-May 1940)

When the campaign started in 9 April, there were perhaps 10 modern ships in service in the Navy, most spread out between major Fjords protecting valuable cities. The Germans thought that Operation weserübung would be a promenade.
The operation was very much a preemptive strike as the allies had many reasons to hit first as well:

Nevertheless, war operations were a disaster for the Norwegian Navy. Although the coastal batteries inflicted severe losses on the Germans, including the Blücher and Königsberg, damaging seriously the Emden and Hipper, most of the heavy casualties were credited to the Royal Navy and fleet air arm. The Norwegian fleet was decimated, the surviving ships being scuttled. Some will be reused by the Kriegsmarine, like the modern TBs of the Odin and Sleipner classes.

The two remaining torpedo of the Odin class indeed (the first was operational at the time of the outbreak of the campaign) were completed and rearmed as KMS Leopard, Tiger and Gyller by the Kriegsmarine. The two Aalesund class destroyers were well scuttled and were never completed. The two Otra class minesweepers, in service at the same time, were captured and reintegrated as Camerun and Togo in the Kriegsmarine.

NWE Norway
The map of operations

On April 8, 1940, the German torpedo boat Albatross attacked and sank the guard ship Pol III. The Battle of Narvik, saw the old coastal defence ships (“panserskip”) HNoMS Eidsvold and HNoMS Norge attempted to make a stand against the approaching German fleet. They were approached by destroyers, torpedoed and sunk. The German invasion fleet bound for Oslo however was significantly delayed duirng the night of 8-9 April: The Oscarsborg Fortress opened fire with her three 28 cm guns (11-in). Soon also on the other side, the 150 mm (6-in) guns of the Kopås bunker (eastern side of the Drøbak strait) joined in and opened fire as well.

The Blücher was badly hit, but the coup de grace went from antediluvian torpedoes fired from Oscarsborg’s land based torpedo battery. There were 1,000 casualties despite the relative proximity to the coast and so far this was the biggest blow to the Kriegsmarine.

The German invasion fleet therefore retreated south, called for the Luftwaffe. The latter bombed Oskarborg. This was neither easy to take on other defended Fjord. Another cruiser was sunk and other badly damaged in the process. The Norwegian Navy barely could make a dent however on the Kriegsmarine, lacking heavy weaponry.

Olaf Tryggvason however laid up a minefield that claimed the German TB KMS Albatross. Captured, the Norwegian minelayer served in the German navy, sunk in Kiel in 1945 as KMS Brummer. While the destruction of the Norwegian fleet was consummated, a few ships were able to take refuge in Great Britain.

The French and British troops helped to recapture the fjords taken by the Germans and two months of relentless fighting to redeem the ports followed. This ended in May when Hitler launched his blitzkrieg in the West. The allies declared “the iron supply is cut off” but in reality, the resistance of the Norwegians ended and the country was occupied, under the presidency of a German military government.

Landings: KMS Hipper at Trondheim
Landings: KMS Hipper at Trondheim


The Norwegian coastal defences greatest success: The Blücher sinking in Olsofjord.

Mobilized Auxiliary ships

CONVERTED MERCHANT VESSELS

-Cargo Farm (1900, 424 tons)
-Auxiliary patrol Trawlers Alpha, Alversund, Andenes, Beta, Commonwealth, Fosen, Furu, William Barents, Lyngdal, Haus, Manger, Lindås, Oygar, Oster, Smart, Veslefrikk, Veslegutt, Heilhorn, Stenkjær, Nauma, Kelt, Svalbard II, Kvitøy, Sperm, Rundøy, Ramoen, Sætre.
-Auxiliary patrol whalers: Bodø, Farsund, Firern, Gos, Gos 9, H. J. Bull, Haug II, Haug III, Honningsvaag, Horten, Hval II, Hval III, Hval IV, Hval VI, Hval VII, Kos I, Kos XX, Oter I, Pol III, Risør, Skudd I, Skudd II, Treff.
-Auxiliary mineweepers Trawlers:
Alcmaria, Børtind, Nordhav II, Syrian.
-Auxiliary minesweeper Whalers: Bjerk, Brevik, Egeland, Globe V, Hval V, John Williamson, Kos IV, Kos XIV, Kos XV, Kos XVI, Kos XVII, Kos XVIII, Noble Nora, Pol II, Pol IV, Pol VI, Polar 6, Thorodd, Transvaalia.

The Free Norwegian Navy (1941-45)

The delay to take Oslo allowed King Haakon VII, the Royal family and the government, to escape. They would make it later in the UK as exiles on June 7, 1940. The fleet comprised thirteen vessels, five aircraft and 500 men from the Navy. They will continue the fight from there. Many Norwegians living abroad and citizens fleeing on trawlers and all sorts of ships also joined civilian sailors escaping from Norway, to what became the RNoN. Funds were used to buy new ships, aircraft and equipment, allowing the “Free Norwegian Navy” to serve with distinction until 1945.

Norwegian motor launches off Dover
Norwegian motor launches off Dover

After the legitimate government and King Haakon VII went into exile in Britain, as well as 92,000 Norwegians, most of them refugees in Sweden, some 400,000 German soldiers were gradually stationed in a country of 4 million inhabitants. Soon, the situation became unbearable because of requisitions, with 40% of the GDP being used by the Reich. The merchant fleet, nearly 1,000 ships, had fled to the allies and made their contribution to the Atlantic convoys. As in 1917, many crews drowned after torpedoing U-Bootes.

Meanwhile, from 1942 onwards, the allies decided to help USSR by sending lend-lease hardware via the only way left: Through the northern route to Mourmansk. A hazardous, treacherous and seasonally opened way the Germans soon trid to block by all means. Soon Kriegsmarine’s ships returned to the Norwegian fjords, created facilities, bases for the Luftwaffe and new fortifications. The most prominent ship which was based here was KMS Tirpitz, for long a primry target for the RAF and later Royal Navy midget submarines. However Norwegian resistance spotted them and transmitted German preparations to the MI6 back in London.

But meanwhile the Norwegian resistance was doing its own. In Finnmark, the country was no more than a large garrison where the German troops, depressed by days and nights of the Arctic Circle, were replaced by troops of very diverse origins, in addition to prisoners of war, which facilitated bolder secret operations. The one against the heavy water supplies that ended any attempt by the Reich to have an create the first atomic bomb was a tremendous success.

Northrop N-3PB in flight
Norwegian Northrop N-3PB in flight No.330 (Norwegian) Squadron based in Iceland.

The forces that had escaped to the United Kingdom were slowly built up over the next few years. On D-Day (6 June 1944), the Royal Norwegian Navy joined the invasion of Normandy with ships and 1,000 sailors. During the war, the RNoN operated 118 ships total and 58 ships in 1945, with 7,500 men under uniform.

Gradually, local resistance added to British commandos regained the ground lost in 1945 and until the capitulation. The many refugee crews in England found an assignment on many ships in the Royal Navy as well, allowing the Norwegian government to continue the struggle. In addition the allies provided many ships, sure to find volunteers:

-4 S class destroyers (1943-44)
-5 1920 “flush-deckers” ex-US DDs (1940-42)
-3 Hunt class escort destroyers (1942).
-3 submersibles of the U “short hull” and “long hull” types (1942)
-7 ASW corvettes of the Flower and Castle classes (1941-44)
-4 SC and PC class sub-chasers (1942-43)
-20 Motor torpedo launches (1940-43)
-9 Multi-purpose patrol launch of the type Fairmile B – and ML types (1941-43)

Guard little Norway Toronto
Guard at the Little Norway training camp in Toronto, Ontario, Canada

Read more/Src:

Robert Gardiner, Conway’s all the world’s fighting ships 1865-1905, 1906-21, 1922-47.
http://fr.naval-encyclopedia.com/2e-guerre-mondiale/marine-norvegienne-2egm.php
https://en.wikipedia.org/wiki/Norwegian_campaign
http://www.navypedia.org/ships/norway/no_index.htm
http://www.akershus.com/en/Follo/product/?TLp=180567&Oscarsborg-Fortress=
Tandstad, Ingvill (4 April 2014). “Oscarsborg fredes”
Historic archives in the old official website of the RNN
Royal Norwegian Navy Museum
The Royal Norwegian Navy during ww2
The Norwegian Navy in 1940-45 – redsal.org

Nomenclature of Norwegian ships

The Norwegian navy was starving in 1939. It consisted of four Antediluvian coastal battleships (1897 and 1900) of the Norge and Haarfarge classes, three ww1-vintage Draug class destroyers (1908), 26 second-class torpedo boats and three first-class TBs. These were recent Sleipner class coastal torpedo boats, three more in construction.

Three submersibles class A (1913) and six class B (1922), the minelayer Olaf Tryggvason (1932), Fröya, and two class Glommen (1916), the old sloops Sars and Heimdal (1892 and 1900), and seven light gunboats dating from 1878 to 1886, plus the modern but weak patrol ships Nansen (1930), Nordkapp and Senja (1937) completed this nomenclature in April 1940. Alto in construction were the Aalesund class DDs, Odin class TBs and Otra class minelayers. However hundreds of fishing trawlers were mobilized as patrol ships and several whalers were converted as minelayers.

Coastal Battleships

We will not dig deep into these ships as they are already covered pretty well in the WW1 section.

Norge class (1900)

The British-built, 1900 Eidsvold class were the backbone of the Norwegian Navy until the German invasion of Norway in 1940. They were supposed to be replaced by the more modern and powerful Bjørgvin-class coastal defence ships in 1915, but both were requisitioned by the RN and used as HMS Glatton and Gorgon during WW1.

HNoMS Norge and Eidsvold were sunk during the first Battle of Narvik. Their heavy armament was more capable than the 270 mm pieces carried by the old gunboats of the 1870-80s converted as minelayers (see below), and comprised for each ship, two 210 mm (8.26 in) guns in single turrets fore and aft, six 15 mm (5.9 in) guns, either side in casemates, eight 76 mm (3 in) guns, four mounted in the battery and the other fore and aft.

In addition they had four 4.7 cm (1.85 in or 3-pdr) QF for self-defence against torpedo boats plus two 450 mm (18 in) submerged torpedo tubes.
It seems they had not been modernized. When the invasion broke out, both ships were at Narvik and HNoMS was sank by German destroyer Wilhelm Heidkamp (Z21) and HNoMS Eidsvold by Bernd von Arnim (Z11).

Haarfarge class (1900)

Eidsvold and Tordenskiold
Models of the two battleships, showing the Eidsvold and Tordenskiold.

These slightly older vessels (HNoMS Tordenskjold and Harald Haarfagre) were considered ‘unfit for war’ in 1940 but they were active nonethess in April. Very close to the Norge class in terms of general design, they displaced 3,858 long tons (3,920 t) for 93 m long, were built in UK in pre-dreadnought fashion with single turrets and protected by Harvey armor plates, with a belt of 7–4 in (178–102 mm) and turrets 8–5 in (203–127 mm) thick. Armament was about the same as the Norge class. They used Coal-fired vertical triple-expansion steam engines, 3 horizontal boilers, they were capable of 16.9 knots (31.3 km/h; 19.4 mph).

KMS Nymphe, Norwegian Harbour
KMS Nymphe as rebuilt and camouflaged, in a Norwegian Harbour

German Reconstruction
As rebuilt as a FLAK-Schiffe, Tordenskjold became KMS Nymphe, armed with six 10.5 cm AA guns, placed fore and aft of the main superstructure and additional positions for two 40 mm AA guns and fourteen 20 mm AA guns.

KMS Thetis
KMS Thetis, Flak-ship, converted from HNoMS Harald Haarfrage (the blueprints).

Destroyers

Draug class (1908)

HNoMS Draug

These three locally-built prewar destroyers, Draug (1908), Troll (1909) and Garm (1913), displacing 540 to 578 tons, were built at Horten Yards. They superficially looked like American prewar destroyers with their four funnels, but it’s difficult to see a definitive influence there. They were propelled by two VTE engines rated for 8000 hip for the first two, and Garma tried German turbines instead. She was the fastest at 27.4 knots. The two others were capable of 26.5 and 27 knots respectively.

Their boilers were coal-fired, and they carried 105 tons. Their armament was conditioned by their small size, six 76 mm (3 in) guns under masks, one at the front in a superfiring position, one on the roof aft and two amidship, each side of the funnels, as well as the two single trailing tubes. The third 357 mm (18 in) tube was axial, posted at the stern.

Their operation record shown though they were still enlisted, they had been already mothballed before 1939. They were recommissioned but were in poor conditions and needed some care to became fully operational again. They were considered fit only for escort and guard service and were part of the 1st Destroyer division at Bergen in early 1940. However as the German invasion was imminent, moved towards Norwayall three ships were transferred to the 2nd Naval District in south- and mid-western Norway and separated, Draug at Haugesund, Garm at Bergen and Troll at Måløy. Draug duelled with German transports on her way to UK on 9 April 1940.

Garm was later sunk by Stukas at Bjordal, Sognefjord, on 26 April 1940. Troll was abandoned by her crew at Florø and later captured by German forces which used her for specialized roles like an heating barge in the shipyard at Laksevaag. Draug would actively serve as an escort ship with the allies until 1945.

Aalesund class

Aalesund class
Probable appearance of the Aalesund class according to summary blueprints (Conway’s).

These three ships were in construction in Horten yards when the Germans invanded Norway. Unfotunately they had been started when war became probable, laid down in April 1939. The first was named Aalesund but the second was unnamed. They were substantial ships and would have been very interesting, original ships if built.

As destroyers for 1940 standards they were still small, scale d down to Norway’s need but still packed a punch. They were 1220 tons, 100 m long ships, propelled by Turbines to 34 knots, and their armament was to include four 120 mm guns (forward twin mount, two single masked guns at aft in a superfiring pair), two 4 mm Bofors AA located behind the funnel and before the TT banks, two 13 mm AA located fore and aft of the funnel in nacelles, and two twin 533 mm TT banks, which was still weak for DD standards though.

Captured on the stock, both destroyers were to be completed for the kriegsmarine, at first as TA7 and 8 and renamed ZN-4 and 5 (‘Zerstörer – Norge’). Fortunately, Norwegian resistance succeeded in sabotaging the construction, resulting in massive delays. German modifications would have included a 1694 tons displacement, single quadruple 533 mm torpedo tubes bank, two 37 mm AA FLAK 38, and six 20 mm AA. Radius was to be 3100 nm for 19 knots. They were never completed, even by the Norwegians after 1945 as their design was already abosolete and needs were covered already by modern British destroyers, and broken up in 1950.

Torpedo Boats

The order is given from the oldest to the most recent.

Odin class TBs (1936)

Odin class TBs
The follows-up of the successful Sleipner class, they were laid down in 1938. Two were built at Horten N Yd (Odin and Balder) and the third, Tor, was to be built at Frederickstad Mek Verstad. Only Odin was in service in April 1940, she has been launched in January 1939 and the two others in October 1939 and September 1939 respectively.

They were improved on certain details but otherwise similar so the sepcs remains the same except they had just two 102 mm guns instead of three. Odin surrended at Kristiansand in 11 April 1940, but Balder and Tor were captured while fitting out. They were completed by the Germans to be used as Leopard and Tiger, armed with a single 102 mm, 2-4 x 40 mm AA, two 8 mm MGs, and the TTs were removed. They were retroceded in 1945 and served until 1959, modernized like the Sleipner class ships as Frigates.

Sleipner class TBs (1936)


ONI archive recognition plate of the TB-43-46 in German service. Its aspects is significantly different from the original design.

HNoMS_Gyller_May_1953

Certainly the most potent and most modern ships of the Norwegian navy, the Sleipner class torpedo boats were ordered in 1933 and laid down in 1934, 35 and 37 as Sleipner, Aeger and Gyller at Horten naval Yard. They were still small even for 1930s TBs at 708 tons fully loaded, but were capable of 30 knots, armed with 21-in torpedoes and capable of minelaying operations. Indeed rails were fitted to their deck, running from the forecastle. In addition they also carrier four ASW deep charge launchers.

Their artillery was not ridiculous either with three 102 mm/40 (4 in) under masks, positioned on the forecastle, and two in superfiring pair aft. The twin torpedo tubes bank was placed behind the single funnel. Between N°2 gun and this bank was located the 40 mm Bofors AA gun. This made these ships quite versatile warships. The design was such a success it was repeated on the next Ordin class (in construction when the war broke out), they served with the Kriegsmarine and back with the Norwegian Navy as frigates right up to the late 1950s.

Sleipner escaped to UK and servd with the Free Norwegian Navy until 1945. Aeger was bombed by the Luftwaffe on 9 april 1940 and Gyller surrendered at Kristiansand on 11 April. She served as the German Löwe until 1945 and was retro-ceded to the Norwegians. She served until 1959 and Sleipner until 1956. At that time they had been comprehensively modernized, with modern electronics, three QF automated 76 mm (3 in) AA guns, two Bofors 4 mm and two 20 mm AA guns and fitted for minelaying.

HNoMS_Sleipner_FrigateH48

Sleipner class Specifications

Displacement: 597 – 708 tons FL
Size: 72 m – 74.30 m oa L x 7.80 x 2.10 (243 x 25 x 6 ft)
Machinery: 2 shaft De Laval Turbines, 3 Yarrow boilers, 12,500 hp, 30 knots
Radius: 3500 nm at 12 knots
Armament: 3x 102 mm/40, 1x 40 mm AA, 2 MG, 2x 533 mm TTs, 4 DCT, mines.

Snögg class TBs (1919)

These postwar large torpedo boats were the first 1st class high seas TBs of the Royal Norwegian Navy. They displaced 256 tons, for 53x 5.5 x 1.8 m in size (173 x 18 x 5 feets), were powered by two shafts VTE rated for 3500 ihp (2 boilesr), oil-fired, with 33 tons carried. They were capable of 24-15 knots and were armed by two 76 mm (3 in) guns and two twin banks of 457 mm (18 in) torpedo tubes, plus mine tracks were fitted on their decks. They are references also as Trygg class, entering service in 1920-21.

They were perfectly active in WW2. Snögg has been abandoned in April 1940, and was captured, served into the kriegsmarine until 1943 as V5504. She was beached at Bergen until the end of the war. Stegg was one of the rare ship sunk in combat, duelling on 20 april 1940 against the German ship KMS Bremse at Heröysund (Hardangerfjord). A hit exploded one of her torpedoes. Trygg was also sunk in action by Stukas on 22 April at Aandalses but she was recovered and repaired by the Germans and became V5503. She was sunk by the allies at Hjelterfjord in 1944.

Teist class TBs (1907)

These 92/108 tons boats were among the most modern in WW1 and still were serviceable in WW2 as well, active in 1940. They measured 41.1 m by 4.7 m by 2.3/2.4 m draught (134.1 x 15.5 x 7.7 feets.inches). They had one single shaft driven by a VTE fed by two coal-burning boilers rated for 1700 hp, enough to reach 25 knots, carrying 15.4 tons of coal. They were armed by two 47 mm guns or a single 76 mm (3 in) and three 357 mm (18 in) Torpedo Tubes, in the bow and two aft axial ones.
Teist was scuttled at Drange, Skarv was captured at Egersund, Kjell in drydock at Kristiansand, and she became the KT-1 and later Grenadier patrol boat.

Ravn class TBs (1903)

Thes five 70 tons coastal TBs (Ravn, Örn, Lom, Jo, and Grib) were blown up by their crews to avoid capture off Lyngör but two others (örn and Lom) were captured under repairs at Horten, renamed Schlange and Eidesche and used as patrol crafts until 1945.

Hval class TBs (1896)

Built in 1895-1902 these nine coastal TBs, VTE with coal-burning boilers, 84 tons, were in part mothballed in the interwar. Hval was striken in 1931, Delfin in 1927, Trods circa 1933, and the remainder boats (Brand, Storm, Skrei, Sael, Sild and Laks) were in semi-active service in 1939. Hval and Delfin were captured and reused by the Germans despite their poor condition, mothballed fro years but not scrapped. Brand was captured at Laksevaag on 11.4.1940 and renamed Tarantel in German service and later NB19 and V5519. She survived and was retroceded in 1945. Sael was attacked and sunk by S-Bootes, Laks captured under repairs but left unrepaired and unused by the German navy.

Hvas class TBs (1898)

These four ships were 64 tons, VTE-powered coal-burning ships launched between 1898 and 1903. They were named Hvas, Kjaek, Falk and Hauk. They were all reactivated when the war broke out and in the process of reconversion as minelayers in April 1940. They were captured in 12-17 April and were used as the patrol boats NO23-26 by the Germans until May 1945.

Varg class TBs (1894)

These very old 45 tons TBs (Hvas, Raket, Glimt, Blink, Djerv, Kvik and Dristig) dating back 1894-98 has been partially reformed during the interwar. The three oldest were scrapped in 1923, but the others were operating as patrol crafts. Blink, Lyn and Kvik were captured in April 1940 and pressed into German service as KT2-4, then renamed Kürassier, Musketier, Dragoner, then NK02-04. They were retro-ceded in May 1945 and BU. Djerv and Dristig were being reconverted as minelayers in April 1940 when scuttled to prevent capture. They were even older boats in the inventory in 1923, The three 36 tons Odd class, all scrapped that year.

HNoM Kjell

Submarines

B1 class submersibles (1923)

This six units built at MV Horten (B1-B6) in 1923-30 had rocky beginnings: These were single-hulled submarines of the Holland type, built in Norway under US design, the first one was laid down in 1915. They were launched in 1922-29 and were outdated when ww2 broke out. As customary for Holland boats they were fast and agile underwater but slow on the surface. Top speed was 14.5 knots and they were armed with a deck gun, 76 mm/28 Bofors, plus four 450 TTs (in the bow, with 6 torpedoes in reserve).

The Submarine B1 fled to UK in July 1940 and stayed there for training until July 1944. B2, B4, B5 and B6 were captured by German troops at Kristiansand, Horten and Florö, or the Sunn-fjord between 9 april and 18 may. The first two were broken up, B5-B6 were eventually repaired, overhauled, and re-commissioned by the Kriegsmarine as UC1 and UC2 in November 1940 and 1941. They used for training. UC1 was broken up and UC2 scuttled in May 1945. B3 was scuttled at Tromsö on the 9 june 1940 to avoid capture.

Specifications

Displacement: 420/545 tons
Dimensions: 51 x 5.33 x 3.5 m
Propulsion: 2 shafts Sulzer diesels/2 electric motors 900/700 hp
Top speed: 14.5/10.5 knots surface/underwater – Radius 2900 nm(9)/150 nm(3)
Armament: 1 x 76mm/28 Bofors, four 450 mm TT tubes (bow, 6)
Crew: 23
Max diving depth: 60 m

A2 class submersibles (1914)

These WW1-era submersibles were all ordered to Germaniawerft, Kiel, Germany just before the war broke out. They were typical of the early generations of German U-boats, laid down in 1911, launched 1912 and completed in 1914. The contract concerned four boats, but when the war broke out, the fourth, A5, has been requisitioned by Germans, commissioned as U0 (later UA). They served for the whole interwar and in 1940 they were outclassed but still cane provide some costal defense. A2 was captured by Germans in Oslo-fjord (Bulerne island) on 9 march 1940, sold for scrap. A3 and A4 were scuttled by their crews on the 15 april 1940 in Tönsberg-fjord.

Specifications

Displacement: 420/545 tons
Dimensions: 46.5 x 4.8 x 2.7 m
Propulsion: 2 shafts Germania diesels/2 electric motors 700/380 hp
Top speed: 14.5/9 knots surface/underwater – Radius 900 nm(10)/76 nm(3)
Armament: Three 450 mm TT tubes (2 bow, 1 stern, 5 reserve)
Crew: 17
Max diving depth: 50 m

Miscellaneous

MTB1 class motor torpedo boats (1939)

These four BPB 60ft MTBs were ordered in UK. They were however all requisitioned by the British Government when the war started, re-commissioned by the Royal Navy as motor gunboats as MGB40-43.

OTRA class minesweepers (1939)

HNoMS Otra

These dedicated minesweepers were built at Nyland, Oslo, built in 1939 and in service the same year. They were fitted with a mechanical minesweeping gear and could carry mines as well. They were captured at Horten by German troops on 9 April 1940, commissioned by the Germans as KMS Togo and Kamerun, returned later to Norway after the war and commissioned again in 1947 as minelayers.

Specifications

Displacement: 320/370 tons
Dimensions: 52.1 x 7 x 1.8-2 m
Propulsion: 2 shafts VTE, 900 hp
Top speed: 13.5 knots – Radius 1400 nm(9 knots)
Armament: 1x 40 mm/56 Bofors, 2x 20 mm/70 Oerlikon, 2x 12.7 mm/90 HMG
Crew: 25

HNoMS Otra testing at Nyland shipyard
HNoMS Otra testing at Nyland shipyard

Minelayer OLAF TRYGGVASON (1934)

HNoMS Olav Tryggvason

The very capable, large vessel was built at MV Horten, laid down in 1931, launched in 1932 and commissioned in 1934. HNoMS Olav Tryggvason has been fitted with a very original powerplant, comprising two De Laval geared steam turbines fed by 3 boilers and as auxiliaries, tw 8-cyl diesel-generators and two electric motors. She was armed by a single 120 mm/44 Bofors, one 76 mm/51 Bofors AA and 2x 40 mm/56 Bofors, plus two 12.7 mm/90 heavy machine guns, possibly two twin 450 mm TTs and 280 mines.

The naval press was unanymous about this minelayer, one of the most perfect worldwide when introduced into service. Her original machinery included two geared steam turbines (6000hp) and two diesel-generators. The latter fed the equivalent of 1400hp. The long cruise of the ship still allowed to reach if needed 14 knots under diesels, but under turbines this was 21 knots and she even achieved 23kts at trials.

Due to the local bad weather, Olav Tryggvason had a covered mine deck, while the mines dropped through three stern gangway ports. Sources are conflicting about her twin TT bank, a sources diverge between one twin 450mm TT (centerline) or 2 twin 450mm TT (one each side), at least as designed. Indeed under commissioned by the German Navy, she had none.
Olaf Tryggvason was captured by German troops on 9 April 1940 at Horten, commissioned by the German Navy as KMS Albatross. On May, 3, 1945 she was heavy damaged at Kiel by American plans, sinking in the harbor. She also participated in the Battle of Horten Harbour. A complete separated article will detail every bit of this interesting ship in the future.

HNoMS Olav Tryggvason in German service

Specifications

Displacement: 1596 tons
Dimensions: 97.3 x 11.45 x 3.5 m
Propulsion: 2 De Laval Turbines, 2 Sulzer diesels, electric motors, 4600/1400 shp
Top speed: 14/21 knots (37.04 km/h)
Radius of Action: 3,000 nm (5,556.00 km) at 14 knots (25.93 km/h)
Armament: 4× 120mm (4.72 inch) Bofors, one 76 mm (3 inch) AA, 2 × 12.7 mm AA, 2×2? 46 cm TTs, 280 mines
Crew: 175

Stern view of the mines ports, launching doors of KMS Brummer
Stern view of the mines ports, launching doors of KMS Brummer ex-Tryggvason (Bundesarchiv).

GLOMMEN class minelayers (1917)

HNoMS Glommen

These coastal minelayers were built during the great war at Akers yards, Oslo, laid down in 1916, completed in 1917-18. They had been designed, tailored for service into the Oslo-Fjord. In April 1940 they operated in the area around Melsomvik. Glommen and Laugen were surrendered, captured by German troops on 14 April 1940 at Tunsberg, and re-commissioned as such, according to one source. According to another, they were rebuilt as floating flak batteries (Nki-01, Nki-02).
KMS Glommen was later sunk by British aircrafts on 20 October 1940 in Trondheim-fjord (another source says she was scuttled at Kirkenes by the retreating Germans in 1944) while KMS Laugen survived and was retro-ceded to Norway after the war.

Specifications

Displacement: 351 tons
Dimensions: 42 x 8.5 x 2.3 m
Propulsion: 2 Reciprocating steam engines, 340 shp
Top speed: 9.9 knots (11.4 mph; 18.3 km/h)
Armament: 2x 76 mm/28 Bofors (another source: 2 × 76 mm (3 in) QF guns), 120 mines
Crew: 35

FRØYA minelayer (1917)

HNoMS FrOya

One of the few modern minelayers of Norway when ww2 broke out: Laid down at MV Horten in 1914 she was launched in 1916 and completed the next year, entering service before the end of the war. This was a seaworthy minelayer, very well armed for her limited displacement and, she was fast. By many ways, she was a kind of blueprint for the development of he 1930s Olaf Tryggvason. In the mid-1930s she was modernized as her boilers were converted to mixed coal/oil firing and she carried 95 tons of coal and about 60 tons of oil and she had a 76 mm/28 Bofors. When the German invasion started,
HNoMS Frøya was scuttled by her crew on April, 13, 1940 in the Skern-fjord (Trondheim).

In detail: She was underway from Finnmark to Horten naval base (Oslofjord) on 8 April, stopping at Brekstad harbour, Ørland, just at the mouth of the Trondheimsfjord. Captain T. Schrøder-Nielsen at first declined to cross Hustadvika bay due to the very bad weather and fog, znd tried instead to seek shelter at Brekstad. In the morning of April, 9, the crew spotted German warships approaching, on their way to Trondheim. Trapped, the captain decided to sail into the nearby Stjørnfjord. However the minelayer was soon spotted and repeatedly attacked by recently landed artillery and Luftwaffe bombers.

On 13 April, Schrøder-Nielsen decided to scuttle the ship, having lost hope. Sensitive Equipment was removed, and Frøya’s mines load as well for possible later use. The ship was rammed at great speed ashore at Søtvika. The hull’s valves were opened, explosive detotaned. The ships was later spotted by Kapitänleutnant Wilhelm Rollmann (U-34) and she torpedoed the Frøya, believing she was still recoverable.

Specifications

Displacement: 595 tons
Dimensions: 75.3 x 8.2 x 2.8 m
Propulsion: 2 shafts TE engines, 6,000 hp
Top speed: 22 knots (40.74 km/h)
Armament: 4x 102mm/37 Bofors, 2x 450 mm TT, 180 mines
Crew: 78

Gor class gunboats (1885)

Gor and Tyr were about the same type as the following ships: In 1914, both were converted to minelayers with a single 263 mm/27 gun plus one 120 mm/44 Armstrong Y and carried 55 mines. In the 1920s both ships were rearmed again, Gor with a 37 mm/20 and a 76 mm/28 Bofors and Tyr with a single 57 mm/40 and single 47 mm/46 Bofors. Gor was captured by the German minesweeper М1 off Bremanger in May, 13, 1940, and re-commissioned as an auxiliary. Tyr was captured on 20 April 1940 by the a German armed trawler at Uskedal, and re-commissioned under own name, and later returned to Norway and scrapped.

Brage class gunboats (1879)

Brage and Nor were built at MV Horten, and about the same type as Vale. They were armed with British guns, and like the Vale class, in 1913, both were converted to minelayers, keeping their 267 mm/14 gun and 37 mm/20 piece, plus 149 mm/45 Armstrong FF gun, 47 mm/46 Hotchkiss gun and carried 50 mines, while their displacement rose to 255/270t. Both were captured by the Germans at Tonsberg on 14/4/1940 and served as auxiliaries until the end of the war. A very close vessel was built in 1882 Vidar. She was converted as a minelayer in 1913, rearmed like the two others, captured like them on 14/4/1940 at Tonsberg, and re-commissioned by Germans as NK31. She was scrapped in 1945.

VALE class gunboats (1874-77)

Built at MV Horten they were amongst the oldest vessels in service worldwide when ww2 broke out. These were of the British-design “Elswick” type, with one heavy gun. In 1913, both were converted to minelayers, but they kept their 267 mm/14 RML gun, and single aft 120 mm/44 Armstrong gun, but carried 50 mines. Displacement rose to 238t up to 250t.
Brief specs: 250 tons, 27.3 x 7.9 m, 2 VC engines, 2 boilers, 200 hp, 8 knots, 22 tons of coal, crew 38. Uller was captured by German troops off Bergen, recommissioned but on May, 2,1940 sunk by a Norwegian aircraft in Sogne-fjord. Vale was captured by German minesweeper М1 off Bremanger in May 1940, and recommissioned as an auxiliary vessel. Fate unknown. She was liely broken up or scuttled in 1945.