|Ordered:||5 June 1941|
|Builder:||Blohm & Voss, Hamburg|
|Laid down:||7 April 1942|
|Launched:||17 December 1942|
|Commissioned:||4 February 1943|
|Fate:||Sunk 29 March 1944|
|Class and type:||Type VIIC submarine|
|Height:||9.60 m (31 ft 6 in)|
|Draught:||4.74 m (15 ft 7 in)|
|Complement:||4 officers, 40–56 enlisted|
|Operations:||Sunk 7 days into her first patrol|
German submarine U-961 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine during World War II. U-961 was constructed at Hamburg during 1942 and 1943, completing her working-up cruises in the Baltic Sea in the spring of 1944. Due to extensive modifications and shortages of supplies during her construction and training, U-961 took nearly two years to be ready for active service, an exceptionally long time.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-961 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).
The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum submerged speed of 7.6 knots (14.1 km/h; 8.7 mph). When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph). U-961 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, 220 rounds, and one twin 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
U-961 departed on her only war patrol on 23 March 1944, under the command of Oberleutnant zur See Klaus Fischer, a veteran submariner. After leaving Marvika at Kristiansand in Norway, U-961 headed directly for the North Atlantic Ocean, the main battleground of the Battle of the Atlantic. By 1944 however, the region had become a U-boat graveyard, as drastic improvements in submarine detection and destruction had been made, both by surface shipping and by allied aircraft.
The patrol lasted just seven days, ending during an attack on convoy JW 58 150 nautical miles (280 km) north of the Faroe Islands on 29 March. As U-961 approached the convoy, she was discovered underwater by the detection equipment on the convoy escort HMS Starling and immediately destroyed with depth charges, at position Coordinates: . The boat never even managed to surface, sinking to the bottom with all 49 sailors on board.
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- Gröner 1991, pp. 43-46.
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