The Whirlwind engine was developed in 1926 by engineers Lawrence, Jones and Heron under the direction of P. B. Taylor, with the aim of producing a reliable medium-power powerplant.
It proved to be an extremely successful design. In 1927, Charles Lindbergh made a transatlantic flight from New York to Paris in the Ryan NYP “Spirit of St. Louis” aircraft, powered by a J-5C Whirlwind engine. Engines of this type were also produced under licence in Poland in the 1930s by Polskie Zaklady Skody and the Avia factory.
Whirlwinds in 5-, 7- and 9-cylinder versions were used to power training, observation, liaison aircraft and airships. Produced under licence by the Continental company, they were also used to power tanks (M3 Lee, M4 Sherman, Ram) and self-propelled guns.
| Configuration | 9-cylinder radial |
| Cooling | air |
| Compression ratio | 6.3 |
| Displacement | 15.9 l |
| Weight | 300 kg |
| Maximum power | 400 hp at 2300 rpm |
| Rated power | 365 hp at 2100 rpm |
