The Pratt & Whitney R-1340 Wasp was 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.
Note: R for Radial and 1340 for 1340 cubic inch displacement.
R-1340-7
450 hp (340 kW), 600 hp (450 kW)
R-1340-8
425 hp (317 kW)
R-1340-9
450 hp (340 kW), 525 hp (391 kW)
R-1340-16
550 hp (410 kW)
R-1340-17
525 hp (391 kW)
R-1340-19
600 hp (450 kW)
R-1340-19F
600 hp (450 kW)
R-1340-21G
550 hp (410 kW)
R-1340-22
550 hp (410 kW)
R-1340-23
575 hp (429 kW)
R-1340-30
550 hp (410 kW)
R-1340-31
550 hp (410 kW)
R-1340-33
600 hp (450 kW)
R-1340-48
600 hp (450 kW)
R-1340-49
600 hp (450 kW)
R-1340-AN1
550 hp (410 kW), 600 hp (450 kW)
R-1340-AN2
550 hp (410 kW), 3:2 geared prop shaft
R-1340-B
450 hp (340 kW)
R-1340-D
500 hp (370 kW)
R-1340-S1D1
525 hp (391 kW)
R-1340-S1H1-G
550 hp (410 kW), 600 hp (450 kW)
R-1340-S3H1
600 hp (450 kW)
R-1340-T1D1
520 hp (390 kW)
There is a Wasp A and three Wasp C's on display at the New England Air Museum, Bradley International Airport, Windsor Locks, CT.
Data from Jane's.
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 in3 (22 L)
Diameter: 51.75 in (1.314 m)
Dry weight: 930 lb (422 kg)
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
Power output: 600 hp (447 kW) at 2,250 rpm at 6,200 ft (1,890 m)
Specific power: 0.45 hp/in³ (20.3 kW/L)
Compression ratio: 6:1
Power-to-weight ratio: 0.65 hp/lb (1.05 kW/kg)
