On 26 February 1943 Cunday was on patrol when he spotted on the surface. The U-boat crash-dived as Cundy dropped depth charges without any visible effect. The Liberator continued its patrol and shortly afterwards saw a second submarine, , which was attacked with the remaining depth charges. They saw the U-boat's bows appear almost vertically, and sink below the surface, so were rather surprised to see her surface and sail away some time later. However, "U-508" had been damaged and was forced to return to Lorient.