August 1944, The P-39 was one of America's first-line pursuit planes in December 1941. It  made its initial flight in April 1938 at Wright Field and by the time of the Pearl Harbor attack, nearly 600 had been built. Its unique engine location behind the cockpit caused some pilot concern at first, but experience showed that this was no more of a hazard in a crash landing than with an engine located forward of the cockpit. However, the P-39's spin characteristics could be quite a problem if proper recovery techniques were ignored.

The Airacobra saw combat throughout the world, particularly in the Southwest Pacific, Mediterranean, and Russian theaters. Because its engine was not equipped with a supercharger, the  P-39 performed best below 17,000 feet altitude and it often  was used at lower altitudes for such missions as ground strafing. When P-39 production ended in August 1944, Bell had built 9,584 Airacobras, of which 4,773 had been allotted to the Soviet Union. Russian pilots particularly liked the cannon-armed P-39 for its ground-attack capability. Other P-39s served with French and British forces.