220 rounds, and a C/30 antiaircraft gun. The boat had a complement between 44 and 60. Service history Initial voyage to Helgoland Following construction, which was completed on 4 December 1940, U-552 was given two months of working-up training, during which she prepared her crew and equipment for the operations ahead. She then sailed from Kiel on 13 February to Helgoland for her first official patrol, arriving there on 18 February 1941. This port city was to remain U-552s home base until she was transferred to the occupied French port of St Nazaire in mid-March 1941. First patrol U-552s first official war patrol began on 18 February 1941, when she left Helgoland for a patrol in the North Sea and the North Atlantic south of Iceland. This first operation yielded one British tanker and one Icelandic trawler carrying fish. The British tanker Cadillac was sunk just north of Scotland on 1 March, while the trawler was sunk just south of Iceland on 10 March. Following these victories, U-552 headed back to St Nazaire. The remainder of her later patrols were all conducted from the French city, which gave her easy access to the Atlantic Ocean and allowed her more time at sea. Second patrol U-552 began her second war patrol on 7 April 1941, when she left her new home port of St Nazaire for the North Atlantic. The U-552 arrived in her assigned patrol area south-west of Iceland on 11 April. No targets were engaged until 26 April when at 18:09 GMT, the U-552 was midway between Iceland and northern Scotland. Topp sighted “smoke cloud bearing 10°T” from a small “patrol vessel size” target. The target was followed “at the limit of visibility” while waiting for nightfall. At 00:10 (27 April), about 130 nautical miles SE of Iceland, the small vessel Commander Horton was attacked. The U-552 log records “Fishing trawler (patrol vessel) sunk with 82 shots of 8.8 cm and 102 shots MG C30. No resistance.” (Commander Horton, 227 tones, 14 casualties). Around 11:00 GMT on 27 April, the U-552 was submerged and “Propeller sounds heard bearing 200°T”. Topp then commenced a surface pursuit of a large steamer. “Estimate enemy speed 16 knots. Am gaining only as a result of the zig zags.” At 14:12, at grid position AL3236, the Beacon Grange was in the targeting range of 1000 meters. The submerged U-552 fired a fan of three