German submarine U-311 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 21 March 1942 at the Flender Werke yard at Lübeck as yard number 311, launched on 20 January 1943 and commissioned on 23 March under the command of Kapitänleutnant Joachim Zander.
During her short career, the U-boat sailed on two combat patrols, sinking a single ship, before she was sunk on 22 April 1944.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-311 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Garbe, Lahmeyer & Co. RP 137/c double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-311 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and two twin 2sp=usNaNsp=us C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.
After training with the 8th U-boat Flotilla at Kiel, U-311 was transferred to the 1st U-boat Flotilla based at Brest in France, for front-line service on 25 November 1943. On that day she departed Kiel and sailed out into the middle of the Atlantic, via the North Sea and the gap between Iceland and the Faroe Islands.[1] She operated as part of 8 wolfpacks before arriving at Brest on 26 January 1944.
U-311 sailed from Brest on 7 March 1944. On the 19th, she sank the Seakay west of Fastnet. On 22 April, she was sunk by depth charges dropped by the Canadian frigates and .[2]
The boat was previously thought to have been sunk southwest of Ireland on 24 April 1944 by a Canadian Sunderland flying boat of 423 Squadron, RCAF.[3] [4]
U-311 took part in eight wolfpacks, namely: