Leonard Cheshire took command of 617 Sqn in December 1943 and so keen was he to do this that he agreed to drop a rank to Wing Commander. Operational since June 1940 he had already completed three tours on Whitleys and Halifaxes earning the DSO and DFC. By the end of January 1944 though Cheshire was unhappy with the accuracy of the target making being provided to the Squadron and along with Sqn Ldr �Mick� Martin devised a plan to dive onto the target, in a four engined heavy bomber no less and accurately mark it from almost zero feet. Permission was given to test this method against the Aero Engine factory at Limoges, France on the 8th February 1944. Initially he buzzed the factory three times to warn the French workers of the raid and on his fourth run he released his markers from just 50ft right at the centre of the target.