On the 9th August, 1943, Sergeant Instructor Cook was despatching a squad of parachute trainees from a C47 aircraft on a dropping zone in North Africa when Private Trevor jumped, his parachute failed to open, and he was suspended underneath the aircraft on the end of his static line at approximately 800 feet above the ground.
Sergeant Instructor Cook realising what had happened, stopped other men from jumping and attempted to pull Private Trevor back into the aircraft but failed. Sergeant Instructor Cook thereupon took a parachute off one of the men in the aircraft and put it on and hooked himself up to the aircraft. He then left the aircraft and climbed down the static line of Private Trevor and gripped him by his feet; whilst holding on to Private Trevor's static line with his right hand he attempted to release the parachute with his left hand.
Whilst doing this the slipstream of the aircraft began to force his own rigging lines out of the bag, and owing to the two bodies swinging around, these lines began to wind around Private Trevor's static line. Sergeant Instructor Cook, realising that his own parachute was becoming fouled, ordered Private Trevor to hold on to him whilst he dropped, in an effort to pull Private Trevor free and enable both bodies to descend on his own parachute.
Sergeant Instructor Cook thereupon released himself, but Private Trevor was unable to retain his grip on the instructor's harness, Sergeant Instructor Cook's parachute then developed and he landed safely. On inspecting his parachute he discovered that five of the rigging lines had been broken during his attempt to free Private Trevor, who was subsequently pulled back safely into the aircraft.
Throughout this action, Sergeant Instructor Cook displayed a complete disregard for his own personal safety and, although unsuccessful, he made an exceptionally courageous effort to release his pupil's parachute.