During the first 5 months of 1945 the U-boat Arm (UbW) of the German navy dispatched 125 U boat patrols to the Atlantic, operating principally in British coastal waters. By 5 May just 29 were still at large.
On the morning of 7 May U-320, a modified Type VIIC/41 boat under O/L H Emmerich, was 2 days into her first operational patrol and running submerged, when she was detected by an RAF Catalina under Flt/Lt KM Murray of 210 Squadron, Coastal Command. Murray attacked immediately with a pattern of depth charges. U-320 was damaged but not destroyed; Murray sighted oil, and sonobuoys dropped by the Catalina detected hammering. Murray was unable to continue the attack and by mid-afternoon, at his Prudent Limit of Endurance (PLE), was forced to abandon the hunt. Emmerich meanwhile headed for Norway, abandoning his crippled boat the following day. Emmrich and all his crew survived. U-320 was the last U-boat to be sunk in action during the Battle of the Atlantic.
Also on May U-1023, a modified Type VIIC/41 under K/L H Schroeteler, sighted a group of Norwegian minesweepers off Portland Bill. In his first successful attack since the patrol started, in March, he struck. His torpedoes hit NYMS 382, which sank with the loss of 22 men.
At around the same time U-2336, a Type XXIII under O/L E Klusmeier 7 days into her first operational patrol sighted a British convoy in the Firth of Forth. Firing his 2 torpedoes, Klusmeier hit freighters Sneland and Avondale Park, which both sank. 9 men were lost altogether. Both U-boats escaped. These actions took place in the evening of 7 May 1945, just hours before the German surrender.