German submarine U-155 was a Type IXC U-boat of Nazi Germany's Kriegsmarine built for service during World War II. Her keel was laid down on 1 October 1940 by DeSchiMAG AG Weser in Bremen as yard number 997. She was launched on 12 May 1941 and commissioned on 23 August with Kapitänleutnant Adolf Piening in command. Piening was relieved in February 1944 (after being promoted to Korvettenkapitän), by Oberleutnant zur See Johannes Rudolph. Design German Type IXC submarines were slightly larger than the original Type IXBs. U-155 had a displacement of when at the surface and while submerged. The U-boat 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 MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of for use while surfaced, two Siemens-Schuckert 2 GU 345/34 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-155 was fitted with six torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one SK C/32 naval gun, 180 rounds, and a SK C/30 as well as a C/30 anti-aircraft gun. The boat had a complement of forty-eight. Service history Leutnant zur See Ludwig von Friedeburg relieved Rudolph from August to November 1944, when Rudolph resumed command for another month. During these four months, U-155 had the youngest U-boat commander during the war since Von Friedeburg was only 20 years old. In December, Kptlt. Erwin Witte took over, and was relieved in April 1945 by Oblt.z.S. Friedrich Altmeier. Altmeier commanded the boat for one month before the German surrender; she was then scuttled by the Royal Navy. The wreck was located, largely intact, in 2001. U-155 conducted ten patrols, sinking 25 ships totalling , one warship of 13,785 tons and damaging one auxiliary warship of . She was a member of one wolfpack. She sank a warship and a troop transport ship, and damaged a cargo ship, with one salvo of four torpedoes on 15 November 1942 during her