400 Squadron, Royal Canadian Air Force. Seated in aircraft. Royal Canadian Air Force photograph. The squadron was called out on Active Service 3 September 1939 at the start of the Second World War, and on 15 February departed Halifax for England. There it was re-designated as No. 400 Army Co-Operation Squadron on the 1st of March, 1941 in recognition of the fact it was the first squadron to deploy overseas. During the war, it flew the Westland Lysander, P-40 Tomahawk, P-51 Mustang, de Havilland Mosquito and Supermarine Spitfire primarily in the armed and unarmed reconnaissance role. Later in the war, the squadron also flew air interdiction operations. At the end of the war, 400 Squadron was disbanded on 7 August 1945, at a captured airfield in Luneburg, Germany.