The air forces of the United Kingdom – the Royal Navy's Fleet Air Arm, the Army's Army Air Corps and the Royal Air Force use a roundel, a circular identification mark, painted on aircraft to identify them to other aircraft and ground forces. In one form or another, it has been used on British military aircraft from 1915 to the present.
Used on camouflaged aircraft in all positions from Summer 1938 until superseded by Type A.1 roundels. Used on upper surfaces of many aircraft until 1947. On fuselage sides and upper wings of overall PRU blue photo-reconnaissance aircraft 1940 – 1944