a nighttime attack, has been heavily debated. Some of the crew of U-552 survived the war, and her captain, Erich Topp, later became an admiral in the postwar Bundesmarine. No charges were brought against Topp, as happened to Helmuth von Ruckteschell, captain of the raider Widder for a similar offence. Later patrols U-552 had less success in later years, as did the U-boat force in general, as U-boats failed to keep ahead of the rapidly increasing numbers and capabilities of Allied antisubmarine efforts. She was transferred to operations off the Spanish, Portuguese, and African coasts, which were nearer to base and less dangerous than the newly reorganized defenses of the United States, where she attempted to sink troopships during Operation Torch. Whilst on this duty, Topp sank a small British minesweeper and later a cargo ship, but failed to enter the Straits of Gibraltar or seriously threaten the landings. During 1943, U-552 was increasingly unable to serve effectively against the well-prepared and organized Allied convoy system, a fact reflected by her failure to sink a single ship during her two patrols into the North Atlantic Ocean. During one of these, a Royal Air Force B-24 Liberator aircraft spotted her and she was seriously damaged by depth charges, which necessitated four months' repairs. In 1944, she had a single patrol, but was unable to close with or threaten any Allied convoys, so was withdrawn to Germany in April 1944 for use as a training vessel in the 22nd U-boat Flotilla, a role she fulfilled until she was decommissioned in February 1945. On 5 May 1945, she was scuttled in Wilhelmshaven Bay to prevent her capture. Wolfpacks U-552 took part in 21 wolfpacks, namely: Brandenburg (15 – 26 September 1941) Stosstrupp (30 October – 4 November 1941) Störtebecker (15 – 19 November 1941) Benecke (19 – 22 November 1941) Seydlitz (27 December 1941 – 6 January 1942) Zieten (6 – 19 January 1942) Endrass (12 – 17 June 1942) Wolf (13 – 30 July 1942) Pirat (30 July – 3 August 1942) Steinbrinck (3 – 4 August 1942) Meise (11 – 27 April 1943) Star (27 April – 4 May 1943) Fink (4 – 6 May 1943) Naab (12 – 15 May 1943) Donau 2 (15 – 19 May 1943) Mosel (19 – 24 May 1943) Siegfried (22 – 27 October 1943) Siegfried 2 (27 – 30 October 1943) Jahn (30 October