Unterseeboot 155

During World War I, U-155 was launched on 28 March 1916, and commissioned into the Kaiserliche Marine on 19 February 1917.

The second U-155 was a Type IXC submarine of the Kriegsmarine. Her keel was laid down 1 October 1940 by AG Weser, of Bremen. She was commissioned 23 August 1941, with Kapitänleutnant Adolf Cornelius Piening in command. Piening was relieved in February of 1944 (after being promoted to Korvettenkapitän) by Oberleutnant zur See Johannes Rudolph.

Leutnant zur See Ludwig-Ferdinand von Friedeburg relieved Rudolph from August to November 1944, when Rudoph resumed command for another month. During these four months, U-155 had the youngest U-boat commander during the war. Von Friedeburg was 20 years old.

In December, Kptlt. Erwin Witte took over, and was relieved in April 1945 by Oblt. Friedrich Altmeier. Altmeier commanded the boat for one month before being ordered to surrender her.

U-155 conducted 10 patrols, sinking 26 ships totalling 140,449 tons and damaging one other grossing 6,736 tons. On 4 May 1945, the boat shot down a P-51 Mustang from the 126th RAF Squadron.

U-155 lost only five crewmen during her career. On 10 March 1942, she was returning from the US east coast when I WO Oberleutnant zur See Gert Rentrop was lost overboard. On 19 August 1942, during an aircraft attack Maschinengefreiter Konrad Garneier was lost overboard. On 14 June 1943, when a Wellington aircraft of the 547th RAF Squadron attacked in the Bay of Biscay, Bootsmaat Heinz Wilke was killed. On 14 June 1943, four Mosquito aircraft of the 307th Polish Squadron attacked, wounding five men in the Bay of Biscay. U-155 shot down one of the aircraft. On 23 June 1944, Mosquito aircraft of the 248th Polish Squadron attacked, killing Matrosenobergefreiter Karl Lohmeier and Mechanikerobergefreiter Friedrich Feller and wounding seven others.

On 30 June 1945 she was transferred from Wilhelmshaven to Loch Ryan, Scotland[?] for Operation Deadlight.