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.
The main object of the attack was to learn to what extent a first wave of aircraft could guide a second wave to the aiming point by starting a conflagration: I ordered a half an hour interval between the two waves in order to allow the fires to get a good hold before the second wave arrived. In all, 234 aircraft were dispatched and dropped 144 tons of incendiaries and 160 tons of high explosives.