Flying Officer Trigg had rendered outstanding service on convoy escort and antisubmarine duties. He had completed 46 operational sorties and had invariably displayed skill and courage of a very high order. One day in August 1943, Flying Officer Trigg undertook, as captain and pilot, a patrol in a Liberator although he had not previously made any operational sorties in that type of aircraft. After searching for 8 hours a surfaced U-boat was sighted. Flying Officer Trigg immediately prepared to attack.