the troopship S.S. Nerissa approaching from the north-west. For almost 2 hours, Topp stalked the zigzagging Nerissa and adjusted his torpedo firing solution accordingly. Finally, Topp saw a phosphorescent glow on the sea and decided that 1,000 metres was as close as he should approach his target, and he fired a fan of three torpedoes. The U-552 log records that one of the three torpedoes “hit astern” at 00:27 Berlin Time (GMT+2). About 6 minutes later, Topp closed in on the already stricken ship and fired a fourth torpedo as a coup de grace into Nerissa's aft starboard side while her crew and passengers were launching lifeboats. More than half of the 207 casualties were Canadians. (S.S. Nerissa, 5,583 tones, casualties 207) The U-552 had four remaining torpedoes and she continued searching for merchant ships in transit towards the North Channel. Topp was not successful in engaging any additional targets and almost 48 hours after sinking the S.S. Nerissa, the U-552 commenced her homeward transit south. She arrived in St Nazaire on 6 May. Third patrol U-552 left St Nazaire for her third war patrol on 25 May 1941. In 39 days, she travelled into the North Atlantic and sank three British vessels: the Ainderby on 10 June, the Chinese Prince on 12 June, and the Norfolk on 18 June. During the attack on the Norfolk, U-552 attempted to attack the remaining ships in the convoy, but was forced to break off the attack due to the arrival of several of the convoy's escorts. All of these attacks occurred off the northwest coast of Ireland, and once U-552 returned to St. Nazaire on 2 July 1941, she had amassed a total of 24,401 GRT from the ships she had sunk. Fourth patrol U-552s fourth patrol was much less successful than her previous three. Having left St Nazaire on 18 August, she proceeded to head south into the waters off Portugal and Spain. Here, she sank the Norwegian vessel, Spind. Following this sinking, U-552 returned to St Nazaire on 26 August 1941, after only 9 days at sea. Fifth and sixth patrols Her next two patrols all took her further into the Atlantic, where the danger was lessened, but so were the targets, with the result that she only hit three more cargo ships. Also this time, during her final patrol of 1941, she sank the Reuben James, which was torpedoed