German submarine U-731
German submarine U-731 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 1 October 1941 at the Schichau-Werke yard at Danzig, launched on 25 July 1942, and commissioned on 3 October 1942 under the command of Oberleutnant zur See Werner Techand.
Attached to 8th U-boat Flotilla based at Kiel, U-731 completed her training period on 30 April 1943 and was assigned to front-line service.
Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-731 had a displacement of when at the surface and while submerged. She had a total length of, a pressure hull length of, a beam of, a height of, and a draught of. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of for use while submerged. She had two shafts and two 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-731 was fitted with five torpedo tubes, fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and two twin C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.