31 Halifaxes from 427 and 429 Squadrons were ordered on an attack enemy positions at Calais. The crews were over the target at between 1,500 and 2,500 feet, releasing 341,000 lbs of high explosives. According to reports, the target was cloud covered and bombing was scattered. Some crews descended below cloud were they were fired at by accurate light flak. 

F/O E. Mayo from 427 Squadron did not bomb as the load hung up.
F/O F. Wilsher landed at Westcott on return.

F/Lt E. Hawn from 429 Squadron was hit by flak, the rear gunner was injured.
F/O G. Clarke RCAF and crew flying Halifax LW-136 coded AL-Z was hit by light flak. There was serious damage to all the engines, both turrets, compasses, rudder and aileron controls and the port outer caught fire. They turned and headed for Allied territory where the navigator and bomb aimer bailed out over a valley. The rest of the crew stayed aboard as they were losing height and flying towards rising ground. F/O G. Clarke made a good crash landing near Quer Camp, France, where the crew escaped after their Halifax burst into flames and was totally destroyed.

Sgt L. Fry RAF
F/Sgt C. Short RCAF
P/O J. Roy RCAF
F/Sgt G. Pare RCAF
Sgt S. Ogilvie RCAF
Sgt R. Nimmo RCAF