No. 1 Air Ambulance Unit was formed on 15 February 1941 at RAAF Base Laverton and was equipped with three de Havilland DH-86 aircraft. The Unit left Australia for the Middle East in April 1941 and began flying from Gaza in August 1941. The Unit supported Commonwealth units during the North African Campaign and Tunisia campaign from December 1941 until the end of the Tunisia campaign in May 1943. No. 1 Air Ambulance Unit was expanded and reequipped with 11 Bristol Bombay aircraft in February 1943. From July 1943 the Unit supported the Allied invasion of Sicily and deployed to Italy in September 1943 to participate in the Italian Campaign.