The Royal Canadian Air Force (RCAF) grew rapidly during World War Two, starting with only 4,061 Officers and men on September 1, 1939, and ending up as the fourth-largest allied air force by the end of the war, with more than 263,000 men and women. The RCAF officially managed the British Commonwealth Air Training Program, through which it trained 131,553 pilots, navigators, bomb aimers, wireless operators, air gunners and flight engineers in Canadian schools.
Between North America, Great Britain, North Africa, Italy, Northwest Europe and Southeast Asia, Seventy-Eight RCAF squadrons would carry out combat operations, including air-to-air combat, strategic bombing, photo-reconnaissance, anti-submarine patrols, anti-shipping strikes, close air support and tactical air supply. By the time the war was over, the RCAF sustained 13,498 fatal battle casualties, 9,191 if which were Canadians flying with the Royal Air Force's Bomber Command.