In 1945, while with the RAF Pathfinders (No. 582 Squadron), Swales was the Master Bomber and captain of Avro Lancaster III PB538. On 23 February 1945, the very day as his D.F.C. award was gazetted, Swales led the bombing raid on Pforzheim, Germany (not far from Karlsruhe and the Rhine River), where 17,600 civilians were killed in 22 minutes.