R-13401925R-1340Piston enginesPratt & Whitney R-1340 WaspThe first Pratt & Whitney engine, the start of the famous Wasp series.Pratt & Whitney · United States→RM1933Piston enginesRolls-Royce MerlinThe famous V12 engine of the Spitfire, the Lancaster and the later P-51 Mustang.Rolls-Royce · United Kingdom→R-28001937R-2800Piston enginesPratt & Whitney R-2800 Double WaspOne of the most important American aircraft engines of the Second World War.Pratt & Whitney · United States→R-985R-985Piston enginesPratt & Whitney R-985 Wasp JuniorSmall nine-cylinder radial engine of the Wasp family, used in many light transports and bush planes.Pratt & Whitney · United States→R-1535R-1535Piston enginesPratt & Whitney R-1535 Twin Wasp JuniorSmall twin-row radial engine of the Wasp family.Pratt & Whitney · United States→R-1690R-1690Piston enginesPratt & Whitney R-1690 HornetLarger nine-cylinder radial built next to the Wasp.Pratt & Whitney · United States→R-1830R-1830Piston enginesPratt & Whitney R-1830 Twin WaspTwin-row radial engine built in very large numbers during the Second World War.Pratt & Whitney · United States→R-2000R-2000Piston enginesPratt & Whitney R-2000 Twin WaspEnlarged development of the R-1830 Twin Wasp.Pratt & Whitney · United States→