Wright Whirlwind series

The Wright Whirlwind was a family of air-cooled radial aircraft engines built by Wright Aeronautical (originally an independent company, later a division of Curtiss-Wright). The family began with nine-cylinder engines, and later expanded to include five-cylinder and seven-cylinder varieties. Fourteen-cylinder twin-row versions were also developed, but these were not commercially produced.

The Whirlwind series was succeeded by more powerful but still air-cooled radial aero engines, notably the Pratt & Whitney Wasp series and the Wright Cyclone series.