The Type VIIC boat U-558 left Brest on its final war cruise on 8 May 1943, under the command of Kapitanleutnant Gunther Krech. On its return voyage it was attacked in the Bay of Biscay on 20 July 1943 by Liberator (F) of the19th Sqd, 479th Anti-submarine Group, USAAF, flown by First Lieutenant Charles F. Gallimeir, from St. Eval, Cornwall. The U-boat put up intense flak, wounding one of the crew and damaging the port inner engine, but seven depth charges were dropped. More flak came up and the engine cut out. At this point Halifax (DT642) of No.58 Sqd, flown by Flight Lieutenant Godfrey Sawtell, from Holmsey South, Hampshire, took over the attack. This exchanged gunfire and dropped eight depth charges, as shown here. The U-boat sank, leaving thirty men in the water. Five of these got into a dinghy, including krech, and were picked up on 25 July by the destroyer HMCS Athabaskan. Forty-five other were lost. It transpired that U-558 was already sinking as a result of the first attack, with chlorine gas filling the hull.