The British Commonwealth Air Training Plan, or simply the plan, was a massive air-training program set up in Canada by the British Air Ministry.

Ample supplies of fuel, wide open spaces suitable for navigation training, and a lack of Luftwaffe fighters all added up to making Canada a natural location for such an effort. Over 167,000 students, including over 50,000 pilots, trained in the program from May 1940 to March 1945. Canada was referred to as "the Aerodrome of Democracy" during this period, a play on the US being the Arsenal of Democracy. Today all that is left of the plan are a number of triangular airbases scattered across the country. Many of these have been turned into general aviation airports, while others have been used for drag racing.

A similar program was also set up in Australia and New Zealand as the Empire Air Training Scheme.