To facilitate air training, representatives of the Commonwealth established the Empire Air Training Scheme. This brought potential pilots to Australia for initial training and then sent them to Canada for final flight school and dispatch to Great Britain to serve in the RAF. The RAAF established several flight schools in Australia for a program that eventually trained some 37,000 pilots.
The initial deployment of RAAF assets was to support the war in Europe. The entry of Japan into World War II in December 1941 led to a redeployment of Australian squadrons to the Pacific. Japanese military advances and Japan's air raid on Darwin on 19 February 1942 increased pressure for better air defense over Australia. Beginning in 1942, U.S. air units were dispatched to Australia to bolster the RAAF. On 17 April 1942, all RAAF squadrons in the Pacific were placed under the auspices of Allied Air Forces Headquarters, part of U.S. General Douglas MacArthur's Southwestern Pacific Theater command.
The RAAF participated in almost every major campaign of the Pacific Theater. Four RAAF squadrons, two with Hudson bombers and two flying obsolete Brewster Buffalo fighters, fought in the 1941–1942 Malaya Campaign. Later, elements of these squadrons were withdrawn to the Netherlands Indies and finally back to Australia. Two other RAAF squadrons fought in the Netherlands Indies before being relocated to Australia. RAAF units distinguished themselves in the defense of Milne Bay in September 1942.
Early deficiencies in aircraft were overcome with the addition of P-40 Kittyhawk and Spitfire fighters. The RAAF played an important role in supporting ground operations and in attacking Japanese shipping, including during the Battle of the Bismarck Sea. It also assisted in long-range minelaying operations throughout the war. The RAAF also provided wireless units to its troops who participated in the invasion of the Philippines. By the end of the war, the RAAF numbered 131,662 personnel and 3,187 aircraft.
Firkins, P. Strike and Return. Perth, Australia: Westward Publishing, 1985.; Gillison, D. Royal Australian Air Force, 1939–1942. Canberra: Australian War Memorial, 1962.