New England Air Museum
Pratt & Whitney R-1535-96 Twin Wasp Junior


Gift of the Pacific Airmotive Corporation


The R-1535 is perhaps the least known engine in the Pratt & Whitney family of famous Wasp engines and was a smaller version of the R-1830 Twin Wasp. It was developed for the U.S. Navy and was used almost exclusively by the military by both the Army and the Navy in fighters, attack bombers and observation aircraft.

Production continued until 1941 and totaled 2,880 engines. The engine on display powered a Vought SB24-1 "Vindictor" dive bomber of the U.S. Navy. Other aircraft to utilize the R-1535 included:

  • Douglas O-46
  • Grumman F2F
  • Hughes H-1 Racer
  • Northrop A-17, BT-1
  • Vought SBU Corsair

The engine is located in the Civilian Hangar on the wall near the tail of the DC-3.

If you have any information, comments on, or recollections of the R-1535, please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it. .



Type: 14-cylinder, two-row, air-cooled, radial
Displacement: 1,535 cu. in.
Dry Weight: 1,087 lbs.
Power Output: 825 hp
NEAM Id: 22


Engine Collection Index