MILITARY AVIATION 1919-1939

The world's military air services faced difficult times after World War I. The German air force was disbanded by the Treaty of Versailles, while air power advocates in the victorious Allied nations struggled to prove that the airplane was the weapon of the future. Brigadier General Billy Mitchell, who had commanded United States Air Service combat units during World War I, launched a controversial drive for the creation of an independent air force. Court-martialed in 1925 following a series of attacks on U.S. military policy, Mitchell resigned from the service, but not from the fight for increased American air strength.

The American and British navies had experimented with aircraft carriers during World War I. Between the end of World War I in 1918 and the outbreak of World War II in 1939, they built a few larger and faster carriers, with fighters, dive-bombers, and torpedo-bombers built purposely to land and take off from carriers.

Military aircraft evolved slowly in the 1920s. But in the early 1930s a revolution took place in airplane technology, driven by the growing airline industry. New airliners like the Douglas DC-1, first flown in 1933, had strong, streamlined aluminum-alloy structures, more powerful engines, much better propellers, and drag-reducing features such as retractable landing gear. These features were soon incorporated in aircraft such as the American-built Boeing B-17 four-engine bomber, nicknamed the Flying Fortress, first flown in 1935. First-generation all-metal pursuit aircraft such as the Soviet Polikarpov I-16 and the American Curtiss P-36 set the stage for the fighters that would contest the skies in a conflict already looming.