Pratt & Whitney R-4360 Wasp Major

Technical Specs

  • Type:28-cylinder supercharged air-cooled four-row radial engine
  • Bore: 5.75 in. (146.05 mm)
  • Stroke: 6.00 in. (152.4 mm)
  • Displacement: 4,362.5 in³ (71.49 L)
  • Length: 96.5 in. (2 451 mm)
  • Diameter: 55 in (1397 mm)
  • Dry weight: 3,870 lb (1,755 kg)
  • Horsepower: 3,000-3,500

General Information

The R-4360, or ‘Corncob’ engine as it is affectionately called thanks to its offset cylinders, is a large radial piston aircraft engine that was designed and built by US engine manufacturers Pratt & Whitney during World War II. It was the last of the Wasp family of engines and the culmination piston-driven engine technology. WWII came to a close before the 4360 could power anything into combat, however it was used on the last generation of large piston-driven aircraft before technology moved on to the turboprop and turbojet.

Amongst the list of aircraft that employed the 4360, some of the more notable are the: Guppy, Stratofortress, Globemaster, Flying Boxcar, Corsair and Spruce Goose.

Specific Information

This R-4360 came off a KC-97 and though mounted on an engine stand was considered junk. HFM’s Lead Mechanic made a savvy trade for it and brought it to Bellingham from Wyoming.  We are pleased to have it on display!