 1 Squadron deployed to Le Havre in northern France with the RAF Advanced Air Striking Force that accompanied the British Expeditionary Force.Through the autumn and winter of 1939–40, amidst the so-called Phoney War, a succession of small and indecisive clashes took place between the Allied air forces and the "Luftwaffe".Clisby achieved his first aerial victory on 1 April 1940, a Messerschmitt Bf 110 twin-engined fighter over Moselle.