Type 39 torpedo boat

The main armament of the Type 39 class consisted four 42-caliber 10.5 cm (4.1 in) SK C/32[Note 1] guns in single mounts; one forward of the superstructure, one between the funnels, and two aft, one superfiring over the other.[6] Its mount had a range of elevation from -10° to +70° and the gun fired 15.1-kilogram (33 lb) projectiles at a muzzle velocity of 785 m/s (2,580 ft/s). It had a range of 15,175 meters (16,596 yd) at an elevation of +44.4°.[7]

Anti-aircraft defense was provided by a pair of twin 80-caliber 3.7 cm (1.5 in) SK C/30 anti-aircraft (AA) gun mounts positioned on a platform abaft the rear funnel.[6] The power-operated mount had a maximum elevation of 85° which gave the gun a ceiling of less than 6,800 meters (22,300 ft); horizontal range was 8,500 meters (9,300 yd) at an elevation of 35.7°. The single-shot SK C/30 fired 0.748-kilogram (1.65 lb) projectiles at a muzzle velocity of 1,000 m/s (3,300 ft/s) at a rate of 30 rounds per minute.[8] The ships were also fitted with six 2 cm (0.8 in) C/38 guns in one quadruple mount on the aft superstructure[Note 2] and a pair of single mounts on the bridge wings.[6] The gun had an effective rate of fire of about 120 rounds per minute. Its 0.12-kilogram (0.26 lb) projectiles were fired at a muzzle velocity of 875 m/s (2,870 ft/s) which gave it a ceiling of 3,700 meters (12,100 ft) and a maximum horizontal range of 4,800 meters (5,200 yd).[10] Each ship carried 2,000 rounds per gun.[2]

The Type 39s were also equipped with six above-water 533 mm (21 in) torpedo tubes in two triple mounts amidships and could also carry 30 mines; the full complement of 60 mines made the ships top-heavy which could be dangerous in bad weather. They used the G7a torpedo[6] which had a 300-kilogram (660 lb) warhead and three speed/range settings: 14,000 meters (15,000 yd) at 30 knots (56 km/h; 35 mph); 8,000 meters (8,700 yd) at 40 knots (74 km/h; 46 mph) and 6,000 meters (6,600 yd) at 44 knots (81 km/h; 51 mph).[11] For anti-submarine work the ships were fitted with a S-Gerät sonar and four depth charge launchers. The Type 39s were equipped with a FuMO 21[Note 3] search radar.[12]

The former T35 (as DD-935) running trials off Boston, Massachusetts, 14 September 1945

The bridge wing 2 cm mounts were replaced by twin mounts in 1943–1944. In January–February 1944, T22, T23, T24 and T27 had their bridge wing guns replaced by quadruple mounts, FuMB7[Note 4] "Naxos" and FuMB8 "Wanz G" radar detectors fitted and a 2-meter (6 ft 7 in) rangefinder installed on the searchlight platform amidships. Other boats received a FuMO 63 K Hohentwiel radar on the searchlight platform and all of them were fitted with a variety of radar detectors late in the war. The 1944–1945 anti-aircraft suite for these ships is not known in detail. Either T23 or T28 received single 3.7 cm, either the Flak M42 or the Flak M43, or 4 cm (1.6 in) Bofors guns in lieu of the bridge wing guns and the twin 3.7 cm SK C/30 guns. T33 and T36 may also have had two twin-gun 2 cm mounts forward of the bridge.[13]

In December 1943, two blockade runners arriving from Japan attempted to pass through the bay. The Allies were aware of them through their Ultra code-breaking efforts and positioned cruisers and aircraft in the Western Atlantic to intercept them in Operation Stonewall. The first ship reached France, but the second one was destroyed by Allied aircraft unbeknownst to the Germans. They had sent the 8th Destroyer Flotilla and the 4th Torpedo Boat Flotilla to escort the ship home; after she failed to arrive at the rendezvous point, the German ships turned for home in very heavy seas that greatly degraded the ability of the torpedo boats to use their guns and torpedoes. An Allied bomber had spotted them on the morning of 28 December and the German ships were intercepted by the British light cruisers Glasgow and Enterprise that afternoon. After unsuccessful torpedo attacks by the destroyers, Kapitän zur See (Captain) Hans Erdmenger, commander of the 8th Flotilla, decided to split his forces and ordered the destroyers Z23, Z27, and T22, T25 and T26 to reverse course to the north. The cruisers pursued the northern group and sank Z27, T25 and T26. All of the ships in the southern group, including T23, T24 and T27 were able to successfully disengage.[20]

T28 and T29 arrived in France in January 1944 to relieve T22 and T23 which returned to Germany for refits in February. T28 began a long refit upon her arrival that was not completed until early June. After laying a minefield off the Sept-Îles on the north coast of Brittany on the night of 25/26 April, the 4th Flotilla, now consisting of T24, T27 and T29, was engaged by an Allied force that consisted of the light cruiser HMS Black Prince and the destroyers HMS Ashanti, HMCS Athabaskan, HMCS Haida and HMCS Huron off the Île de Batz. The Allied ships were faster than the torpedo boats and closed the range despite the German attempt to disengage. The destroyers began firing at T24 and T27 and one hit significantly reduced the latter's speed; Korvettenkapitän (Lieutenant Commander) Franz Kohlauf, the flotilla commander, ordered her into Morlaix Bay and the Allied ships lost her radar reflection amongst the rocks of the bay. A shell later disabled T29's rudder and Ashanti and Huron concentrated on T29 while Haida and Athabaskan continued their pursuit of T24. They disengaged before T24 reached Saint-Malo, and returned to help sink T29.[21]

After emergency repairs, T27 joined T24 in Saint-Malo during the night of 26/27 April. The sisters departed for Brest on the night of 28/29 April and were intercepted by Haida and Athabaskan off Île Vierge. The Germans turned away, firing all of their torpedoes as they turned. One of T24's torpedoes hit Athabaskan which blew up shortly afterward and sank. Haida pursued T27, badly damaging her. While maneuvering, T27 accidentally ran aground and the Canadian destroyer continued to engage until she started a large fire and then returned to the site where Athabascan had sunk to rescue survivors. T24 and a pair of minesweepers failed in their attempt to pull T27 off. British motor torpedo boats (MTB) and aircraft destroyed her wreck in early May. The 4th Torpedo Boat Flotilla was then disbanded and T24 was assigned to the 8th Destroyer Flotilla.[22]

As the Allies began landing in Normandy on 6 June, the 5th Torpedo Boat Flotilla, now consisting of T28 and three older torpedo boats, sortied multiple times from Le Havre over the next week in attempts to sink Allied shipping. Despite the expenditure of over 50 torpedoes and large quantities of ammunition, they were generally unsuccessful, only sinking the destroyer HNoMS Svenner on 6 June.[23] On the night of 8/9 June, the four ships of the 8th Flotilla set out for Cherbourg, but were intercepted by eight Allied destroyers of the 10th Destroyer Flotilla in the Battle of Ushant. The German ships had been spotted first and the British opened fire, with the Germans responding with a four-torpedo salvo from each destroyer that missed when the Allied ships turned to evade them, although T24, the trailing ship in the formation, did not fire because she had no visible targets. The British fire was extremely effective, with Z24, immediately ahead of the torpedo boat, badly damaged only moments after firing her first salvo. She was able to lay smoke and disengage, followed by T24. Haida and Huron pursued the pair until they passed over a British minefield and lost track of the German ships after the Canadian ships were forced to detour around it.[24]

T24 (foreground) and Z24 under attack, 25 August

On the night of 21/22 July, T28 and three E-boats departed Le Havre for Germany, reaching their destination on the 27th, having evaded multiple Allied ships on their voyage. T24, two minesweepers and Sperrbrecher 157 were escorting the aircraft repair ship Richtofen when they were attacked on the night of 14/15 August by the light cruiser HMS Mauritius and the destroyers HMS Ursa and HMCS Iroquois off Les Sables d'Olonne. The torpedo boat laid a smoke screen and near-missed Iroquois with her torpedoes. She was hit once by Iroquois and Iroquois was lightly damaged during the attack. Off Le Verdon-sur-Mer on 24 August, T24 and Z24 were attacked by rocket-firing Bristol Beaufighter fighter-bombers that sank the torpedo boat and badly damaged the destroyer.[25]

While engaged in gunnery practice with the radio-controlled target ship Hessen in the Baltic on 20 November, T34 struck a mine and sank. T30 helped to lay minefields in the Gulf of Finland in April while attached to the 6th Destroyer Flotilla. Together with T31, she was tasked to support Finnish forces in Vyborg Bay and Koivisto Sound during the Vyborg–Petrozavodsk Offensive in June. They fought Soviet MTBs and claimed 3–5 boats sunk on 20 June, but T31 was sunk by a torpedo. While attempting to lay a minefield in the Gulf of Finland on the night of 17/18 August, T22, T30, and T32 accidentally entered a German minefield and were sunk. On 20–21 August, T23 and T28 helped to escort the heavy cruiser Prinz Eugen as she supported a German counterattack near Tukums, Latvia. As the Germans evacuated Tallinn, Estonia, in mid-September, the sisters helped to lay additional minefields in the Gulf of Finland to deny the Soviets access to the western portions of the gulf. On 22 October, T23 and T28 bombarded Soviet positions near Sworbe, on the Estonian island of Saaremaa, breaking up a Soviet attack. A month later, they provided support during a Soviet attack on 19 November, but the Germans were forced to evacuate several days later. T34 sank during gunnery training while still working up after hitting a mine on 20 November. The sisters were attached to the 6th Destroyer Flotilla to lay a minefield off the Estonian coast, but a navigation error caused two of the destroyers to blunder into a German minefield and sink on the night of 11/12 December.[26]

Prinz Eugen, two destroyers, T23, T33 and T35 supported a German counterattack against advancing Soviet forces near Cranz, East Prussia, on 29–30 January 1945. T36 rescued more than 500 passengers from the torpedoed ocean liner MV Wilhelm Gustloff on the night of 30 January. All of the surviving Type 39s supporting German operations in East- and West Prussia until May. That month their mission became to evacuate as many refugees and troops as possible from those areas still in German hands. T36 was damaged by a mine during one such mission on 4 May and was sunk by Soviet aircraft the next day. They helped to rescue hundreds of thousands of people before Germany surrendered on 9 May.[27]

Only four ships, T23, T28, T33 and T35, of the fifteen built survived the war. The Allies divided the surviving ships of the Kriegsmarine amongst themselves in late 1945 and the British were awarded the first pair, the Soviets received T33 and the Americans T35.[28] After protests by France, the Royal Navy turned theirs over in February 1946, which the French renamed L'Alsacien and Le Lorrain.[29] They both began lengthy overhauls that replaced their radars and 3.7 cm guns. The sisters were recommissioned in December 1949 and assigned to the Aircraft Carrier Group of the Mediterranean Squadron. They were later assigned to the Anti-submarine Group before they were condemned in 1954–1955 and subsequently sold for scrap.[16] The Americans commissioned T35 as DD-935 and ran extensive trials with her before transferring the ship to France in 1947 for spare parts.[30] T33 was taken over by a Soviet crew on 1 January 1946 and commissioned into the Soviet Navy four days later. Renamed Primerny on 13 February, she was assigned the North Baltic Fleet two days later. The ship was removed from combat duty and converted into a floating barracks on 30 November 1954 before being renamed PKZ-63 on 28 December. The vessel was transferred for scrapping on 9 November 1956.[17]