151 Halifaxes from 408, 415, 420, 424, 425, 426, 427, 429, 432, and 433 squadrons were joined by 49 lancasters from 419, 428, 431, and 434 squadron s on an attack of the Kalk rail yards at Cologne. The crews were over the target at between 16,000 and 20,000 feet, releasing 1,768,000 lbs of high explosives and 134,000 lbs of incendiaries. According to reports the rail yards were severely damaged and 2 ammunition trains blew up. 

P/O R. MacMillan from 420 squadron landed at Woodbridge on return.
F/Lt. L. Brand and crew noticed many aircraft flying to the target with their navigation lights on.

F/Lt. C. Lundeen from 424 squadron had the port inner go u/s outbound. They bombed from 13,500 feet and returned safely to base on 3 engines.
F/O H. Cowan landed at Fiskerton due to a fuel shortage.

F/Lt. R. Hemphill from 425 squadron was hit by flak, there were holes in the wings and fuselage.

F/O W. Egan from 426 squadron returned early as the hydraulics were u/s.

F/Lt E. Collins and crew from 427 Squadron, flying Halifax III NP-957 coded ZL-L, were attacked by an unidentified twin engine enemy aircraft. There was no claim or damage.
W/Cdr V. Ganderton and crew, flying Halifax III NP-956 coded ZL-J, had the port inner go u/s outbound. They were also attacked by an ME-410, some strikes were seen. They bombed from 13,500 feet and return safely to base on 3 engines.
F/Lt W. Walker landed at Carnaby due to under carriage problems.

F/O G. Pearce from 428 Squadron had the port inner go u/s out bound and stbd inner u/s on return. They landed safely at base on 2 engines.
W/Cdr A. Hull and crew, flying Lancaster X KB-850 coded NA-O, were attacked by an unidentified aircraft, there was no claim or damage.
F/O N. Noel was hit by flak, there were holes in the stbd fin, wing, and tire.

F/O L. Moffatt from 429 squadron landed at Carnaby due to a brake problem.

F/O L. McGuire from 432 squadron was hit by flak, there were holes in the stbd wing and the stbd inner was u/s. They landed safely at base on 3 engines.
F/O L. Loppe had the stbd outer go u/s over the target. They returned safely to base on 3 engines.

P/O J. O’Neil from 433 squadron had the stbd inner go u/s on return. They landed safely at Ossington on 3 engines.