German submarine U-581
|Ordered:||8 January 1940|
|Builder:||Blohm & Voss, Hamburg|
|Laid down:||25 September 1940|
|Launched:||12 June 1941|
|Commissioned:||31 July 1941|
|Fate:||Sunk 3 February 1942|
|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|
|Victories:||One auxiliary warship sunk, 364 tons|
She carried out two patrols and sank one auxiliary warship of 364 tons.
She was scuttled by her own crew after being pursued and attacked by a British warship near the Azores, in February 1942. After 20 years of search, in 2016, in a depth of approx. 900 m, the boat was discovered and filmed 
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-581 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-581 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 an anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The boat departed Kiel on 13 December 1941, moved through the North Sea, negotiated the gap between the Faroe and Shetland Islands and entered the Atlantic Ocean. She docked at St. Nazaire on the French Atlantic coast on the 24 December 1941.
2nd patrol and loss
For her second foray, U-581 left St. Nazaire on 11 January 1942. On 19 January, she likely sank the British armed trawler HMS Rosemonde northeast of the Azores. There is an element of doubt because the small warship was not reported missing until this date.
Summary of raiding history
|19 January 1942||HMS Rosemonde||Royal Navy||364||Sunk|
- Kemp 1999, pp. 78-79.
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- Gröner 1991, pp. 43-46.
- Helgason, Guðmundur. "Walter Sitek". German U-boats of WWII - uboat.net. Retrieved 29 December 2014.
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- British Admiralty, Naval Intelligence Division (April 1942). "C.B. 4051 (42) "U 581" Interrogation of Survivors". U-boat Archive - uboatarchive.net. Retrieved 6 February 2017.
- Video of the wrack