Pratt & Whitney R-1535 Twin Wasp Junior
| R-1535 Twin Wasp Junior | |
|---|---|
| Pratt & Whitney Twin Wasp Junior, at the National Museum of Naval Aviation, Pensacola, Florida | |
| Type | Radial engine |
| National origin | United States |
| Manufacturer | Pratt & Whitney |
| First run | 1932 |
| Major applications | |
| Developed from | Pratt & Whitney R-985 Wasp Junior |
The Pratt & Whitney R-1535 Twin Wasp Junior is an American aircraft engine developed in the 1930s. The engine was introduced in 1932 as a 14-cylinder version of the 9-cylinder R-985, and was a two-row, air-cooled radial design. Displacement was 1,535 cu in (25.2 L); bore and stroke were both 5+3⁄16 in (132 mm).