German submarine U-712
German submarine U-712 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. Commissioned on 5 November 1942, she served with the 8th U-boat Flotilla until 31 October 1943 as a training boat, and as a front boat in the 3rd U-boat Flotilla under Oberleutnant zur See Walter Pietschmann until 14 December, before being replaced by Oberleutnant zur See Walter-Ernst Koch.
Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-712 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-712 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.
Service history
Built as yard number 778 at the HC Stülcken & Sohn shipyard in Hamburg, U-712 was launched on 10 August 1942. After the completion of system checks and crew training, U-712 was transferred to the 3rd Flotilla on 1 November 1943. On 1 January 1944, she was reassigned to the 21st U-boat Flotilla as a training boat. On 3 July 1944, Oberleutnant zur See Koch handed over to Freiherr Eberhard von Ketelhodt, leaving to command. U-712s purpose was succeeded by a similar function with the 31st from 1 March 1945.In the rest of her career under Walter-Ernst Koch and Freiherr Eberhard von Ketelhodt, she served as a training vessel, never having made a single patrol.