Pratt & Whitney Twin Wasp R-1830-90C (R-1830-S3C4-G), 2-Row, Radial 14 Engine

Type: Reciprocating, 14 cylinders, 2-rows, radial, air cooled

Power rating: 895 kW (1,200 hp) at 2,700 rpm

Displacement: 30.0 L (1,830 cu in.)

Bore and Stroke: 140 mm (5.5 in.) x 140 mm (5.5 in.)

Weight: 678.1 kg (1,495 lb)

Founded in 1925 by Frederick Rentschler, formerly the president of Wright Aeronautical, Pratt & Whitney became the world’s biggest aero-engine company. By 1930, its first engines, the Wasp and Hornet had set many world records. Certificated 1n 1933, the Pratt & Whitney Twin Wasp R-1830 was a two-row radial that delivered up to 1,007 kW (1,350 shp), and opened a market unreachable for single-row engines . Beginning in 1936, Pratt & Whitney focused on the R-1830 with single-stage and 2-stage or turbo-superchargers. The engine powered a wide variety of military and commercial aircraft. Production totaled 173,618, more than any other aircraft engine.

The R-1830-90C was a Navy engine and had a two-speed supercharger. It powered Douglas C-47B, TC-47B, C-47D, and C-117A aircraft. The Pratt & Whitney designation for this engine was R-1830-S3C4-G. The commercial version of the engine powered the Douglas DC-3C.