A gathering section of 124 Squadron Spitfires led by Peter Ayerst climbs for height above the bomber stream and a lone Mosquito. This Squadron plus many others was tasked with protecting the bombers over occupied Europe. For these long range missions the Spitfires carry 90 Gallon 'Slipper Tanks' to extend the relatively short endurance of the aircraft. In combat with enemy fighters they would jettison the tanks. However, following a shortage, they were encouraged to bring them back if they possibly could.