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Pratt & Whitney R-4360 “Wasp Major”

The Wasp Major engine was developed near the end of World War II to power the Boeing B-50, an improved version of the successful B-29 Superfortress. 

The R-4360 is a 28-cylinder, air-cooled radial engine that produces a maximum of 3,500 hp and weighs approximately 3,500 pounds (1,575 kg). R-4360s have been used to power various post-WWII USAF bombers, cargo/transports and aerial tankers, including the B-36 bomber, the B-35 Flying Wing, the C-74 Globemaster, the C-97 Stratofreighter, the Consolidated XC-99, the C-119 Flying Boxcar and the C-124 Globemaster II aircraft. It represents the most technically advanced and complex reciprocating aircraft engine produced in large numbers in the United States. The passing of the KC-97 and C-97 series aircraft from Air Force inventory in the late 1970s marked the closing of the era of both the large piston engine and the turbo-supercharger within the USAF.

The museum has two R4360s on display. A functional, motion-activated cut-away engine is located in the Cold War Gallery under the left wing of the Convair B36J Peacemaker. A second, static model is located in the Korean War Gallery on the right side of the Douglas C-124 Globemaster II.

TECHNICAL NOTES:
Model:
R-4360-4
Type: 28-cylinder, four row, air-cooled radial
Displacement: 4,360 cu. in.
Weight: 3,404 lbs.
Maximum rpm: 2,700
Maximum hp: 3,500

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