German submarine U-644

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
History
Nazi Germany
Name: U-644
Ordered: 20 January 1941
Builder: Blohm & Voss, Hamburg
Yard number: 144
Laid down: 1 December 1941
Launched: 20 August 1942
Commissioned: 15 October 1942
Fate: Sunk by British submarine in position 69°38′N 5°40′W / 69.633°N 5.667°W / 69.633; -5.667Coordinates: 69°38′N 5°40′W / 69.633°N 5.667°W / 69.633; -5.667
General characteristics
Class and type: Type VIIC submarine
Displacement:
  • 769 t (757 long tons) surfaced
  • 871 t (857 long tons) submerged
Length:
Beam:
  • 6.20 m (20 ft 4 in) (o/a)
  • 4.70 m (15 ft 5 in) (pressure hull)
Height: 9.60 m (31 ft 6 in)
Draught: 4.74 m (15 ft 7 in)
Installed power:
  • 2,800–3,200 PS (2,100–2,400 kW; 2,800–3,200 bhp) (diesels)
  • 750 PS (550 kW; 740 shp) (electric)
Propulsion:
Speed:
  • 17.7 knots (32.8 km/h; 20.4 mph) surfaced
  • 7.6 knots (14.1 km/h; 8.7 mph) submerged
Range:
  • 8,500 nmi (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph) surfaced
  • 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth:
  • 230 m (750 ft)
  • Crush depth: 250–295 m (820–968 ft)
Complement: 4 officers, 40–56 enlisted
Armament:
Service record
Identification codes: M 49 683
Commanders: Oblt.z.S. Kurt Jensen
Operations: 1 war patrol
Victories: no ships sunk

German submarine U-644 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 1 December 1941 at the Blohm & Voss yard at Hamburg, launched on 20 August 1942, and commissioned on 15 October 1942 under the command of Oberleutnant zur See Kurt Jensen.

Attached to 5th U-boat Flotilla based at Kiel, U-644 completed her training period on 31 March 1943 and was assigned to front-line service.

Design[edit]

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-644 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged.[1] 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).[1]

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).[1] 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-644 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.[1]

Service history[edit]

In April 1943, U-644 was on patrol between the Shetlands and Jan Mayen. British signals intelligence had pinpointed the U-boat's position and HMS Tuna was dispatched to hunt down U-644. On 7 April, the Tuna detected the U-boat only 500 metres (550 yd) away and fired a spread of five torpedoes. Two torpedoes hit U-644, which sank with all 45 crew members on board, there were no survivors.[2]

References[edit]

  1. ^ a b c d Gröner 1991, pp. 43-46.
  2. ^ Busch, Röll 1999, pp. 84-85.

Bibliography[edit]

  • Busch, Rainer; Röll, Hans-Joachim (1999). German U-boat commanders of World War II : a biographical dictionary. Translated by Brooks, Geoffrey. London, Annapolis, Md: Greenhill Books, Naval Institute Press. ISBN 1-55750-186-6. 
  • Busch, Rainer; Röll, Hans-Joachim (1999). Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945]. Der U-Boot-Krieg (in German). IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2. 
  • Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4. 

External links[edit]

  • Helgason, Guðmundur. "The Type VIIC boat U-644". German U-boats of WWII - uboat.net. Retrieved 21 July 2015. 
  • Hofmann, Markus. "U 644". Deutsche U-Boote 1935-1945 - u-boot-archiv.de (in German). Archived from the original on 1 May 2003. Retrieved 21 July 2015.