On the evening of the 30th of March, just after 1800hrs BST, twelve Halifax aircraft from 76 Squadron took off from Tain to commence the first phase of the attack. Ten Halifax aircraft from 10 Squadron took off from Lossiemouth and twelve from 35 Squadron took off from Kinloss for the second phase of the attack. The aircraft would be flying a total distance of approximately 1,300 miles with a total flight time, including time over target, estimated at being around eight to eight and a half hours.
A series of flashes in the smoke followed by a dull, rumbling boom announced the opening of the surface engagement. As if this was a signal, a formation of torpedo bombers flew into sight, skimming just above the sea. Simultaneously an even larger group of high level bombers were briefly glimpsed through the smoke and clouds on the opposite side of the convoy.