Pratt & Whitney Wasp

The Engine On Display

The Museum possesses two Wasp radials.

The description on the first states:

"535 HP Pratt and Whitney 'Wasp' 9 Cylinder Radial

This model, first produced in 1929, was by a USA company destined to become a world leader in its field. The aircooled radial engine to become a world leader in its field. The aircooled radial engine earned a fine reputation in the pre-war period. This engine has been partly cut away to show the operation of the cylinders and the crankshaft."

Type / History

Type 9-cylinder ar-cooled radial engine
Manufacturer Pratt & Whitney
Introduced 1929
Primary users US Military and civil aircraft
Number built 34,966

The Wasp was not properly a single engine, but a family of engines produced by Pratt & Whitney from the 1920s onwards, from the 450 HP of the initial R-1340 Wasp to the 4,300 HP R4360-51VDT Wasp Major that represented the culmination of radial-engine technology.

The R-1340 powered many of the between-the-wars US fighter aircraft and transports. It was used by the T-6 Texan / Harvard / Wirraway trainers, and post-war in a range of applications, including agricultural aircraft and helicopters.

Notably, the aircraft that replaced the Wirraway, the Winjeel, used its "baby brother", the R-985 Wasp Junior, and the Australian wartime Boomerang fighter used its "big brother", the R-1830 Twin Wasp.


Cubic capacity: 1344 (22.02 L)
Maximum power: 542 HP (404 kW) (ranged over
450-600 HP, 336-447 kW)
Weight: 805 lb (365 kg)