At 05.49 hours on 11 April 1943, U-188 fired a torpedo at convoy ON-176 southwest of Iceland and observed a hit on a tanker after 1 minute 34 seconds, which finally sank after 45 minutes with a broken back. At 05.50 hours, two torpedoes were fired and after 1 minute 58 seconds and 2 minutes 11 seconds hits on two ships were heard. At 05.52 hours again two torpedoes were fired, which hit a fourth ship after 1 minute 58 seconds that began to settle by the bow. However, Allied records indicate that only HMS Beverley (H 64) (LtCdr R.A. Price, RN) was hit and sunk at that time. HMS Clover (K 134) (Lt P.H. Grieves, RNR) later picked up five survivors and recovered two bodies, but one of the survivors later died on board.

On 9 April 1943, HMS Beverley had been seriously damaged in a collision with the British steam merchant Cairnvalona (4929 grt) and took station in the rear of convoy, until she was torpedoed some 30 hours later.