Pratt & Whitney R-1340 Wasp
1925 9-cylinder radial piston engine family by Pratt & Whitney
The Pratt & Whitney R-1340 Wasp is an aircraft engine of the reciprocating type that was widely used in American aircraft from the 1920s onward. It was the Pratt & Whitney aircraft company's first engine, and the first of the famed Wasp series. It was a single-row, nine-cylinder, air-cooled, radial design, and displaced 1,344 cubic inches (22 L); bore and stroke were both 5.75 in (146 mm). A total of 34,966 engines were produced.
As well as numerous types of fixed-wing aircraft, it was used to power helicopters, the Agusta-Bell AB.102 and the Sikorsky H-19, and a class of airship, the K-class blimp.
In 2016, it received designation as a Historic Engineering Landmark from the American Society of Mechanical Engineers.
Variants
Note: R for Radial and 1340 for 1340 cubic inch displacement.
Applications
Engines on display
There are a Wasp A and three Wasp C's on display at the New England Air Museum in Windsor Locks, Connecticut.
Specifications (R-1340-S1H1-G)
Data from Jane's.
General characteristics
Type: Nine-cylinder single-row supercharged air-cooled radial engine
Bore: 5.75 in (146 mm)
Stroke: 5.75 in (146 mm)
Displacement: 1,344 cu in (22.02 L)
Length: 47.7 in (1,210 mm)
Diameter: 51.75 in (1,314 mm)
Dry weight: 930 lb (420 kg)
Components
Valvetrain: Two overhead valves per cylinder
Supercharger: Single-speed centrifugal type supercharger, 1:10 step-up
Fuel system: Two-barrel Stromberg carburetor
Fuel type: 91 octane rating gasoline
Cooling system: Air-cooled
Reduction gear: 3:2
Performance
Power output: 600 hp (450 kW) at 2,250 rpm at 6,200 ft (1,900 m)
Specific power: 0.45 hp/cu in (20.5 kW/L)
Compression ratio: 6:1
Power-to-weight ratio: 0.65 hp/lb (1.07 kW/kg)
See also
Pratt & Whitney Wasp series
Pratt & Whitney R-1690 Hornet
Related development
Pratt & Whitney R-985 Wasp Junior
Pratt & Whitney R-1535 Twin Wasp Junior
Pratt & Whitney R-1830 Twin Wasp
Related lists
List of aircraft engines
References
Notes
Bibliography
Bridgman, Leonard.
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