Pratt & Whitney R-1340 Wasp

R-1340 Wasp
The first Pratt & Whitney Wasp
Type	Radial engine
National origin	United States
Manufacturer	Pratt & Whitney
First run	29 December 1925
Major applications	Soko 522 Boeing P-26 Peashooter de Havilland Canada DHC-3 Otter North American T-6 Texan Sikorsky H-19 Junkers Ju 52
Produced	1926–
Number built	34,966
Developed into	Pratt & Whitney R-985 Wasp Junior

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.

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)

Applications

R-1340 powered Curtiss SOC Seagull, 1939

The gondola of a US Navy K-class blimp. One of its two R-1340 engines is being serviced, 1943

• Agusta-Bell AB.102
• Air Tractor AT-301
• Air Tractor AT-401
• Ayres Thrush
• Bach Air Yacht
• Boeing Model 40A
• Boeing 247
• Boeing F3B
• Boeing F4B
• Boeing P-12
• Boeing P-26 Peashooter
• Boeing P-29
• CAC Ceres
• CAC Wirraway
• Curtiss Falcon
• Curtiss F7C Seahawk
• Curtiss O-52
• Curtiss P-6S Hawk
• Curtiss SOC Seagull
• de Havilland Canada DHC-3 Otter
• Douglas Dolphin
• Fairchild FB-3
• Fokker F.10
• Fokker F.32
• Ford Trimotor
• Gee Bee R-1

• Goodyear K-class blimp

• Gee Bee R-2 Super Sportster
• Gee Bee R 1/2 Super Sportster
• Gee Bee YW
• Gee Bee Z
• Gee Bee QED
• Grumman Mallard
• Grumman Ag Cat
• Howard DGA-6
• Ireland N-2C Neptune
• Junkers W 34
• Junkers Ju 52
• Knoll Aircraft Company KN-3
• Kaman HH-43 Huskie
• Lockheed Vega 5
• Lockheed Model 8 Sirius
• Lockheed Model 9 Orion
• Lockheed Model 10-C & 10-E Electra
• Lockheed XC-35
• Loening OL-8
• Noorduyn Norseman
• North American BC-1
• North American T-6/SNJ Texan/Harvard
• Northrop Alpha
• Northrop C-19 Alpha
• Scottish Aviation Twin Pioneer
• Sikorsky H-19
• Sikorsky S-38
• Soko 522
• TNCA MTW-1
• Thomas-Morse XP-13A Viper
• Vought O2U Corsair
• Wedell-Williams Model 45
• Westland Whirlwind (helicopter)

Engines on display

• There are a Wasp A and three Wasp C's on display at the New England Air Museum, Bradley International Airport, Windsor Locks, CT.

Specifications (R-1340-S1H1-G)

Pratt & Whitney R-1340 installed in a T-6 Texan

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

Bibliography

• Bridgman, Leonard. Jane's All the World's Aircraft 1945-46. Hammersmith, London: HarperCollinsPublishers (1994 reprint). ISBN 000 470831-8
• Gunston, Bill. World Encyclopedia of Aero Engines: From the Pioneers to the Present Day. 5th edition, Stroud, UK: Sutton, 2006.ISBN 0-7509-4479-X
• White, Graham. Allied Aircraft Piston Engines of World War II: History and Development of Frontline Aircraft Piston Engines Produced by Great Britain and the United States During World War II. Warrendale, Pennsylvania: SAE International, 1995. ISBN 1-56091-655-9

External links

• "Index of Wasp & R-1340 Designated Engines", a scanned Pratt & Whitney reference document from 1956 detailing the different Wasp versions, their specifications, and the aircraft they were installed in.
• "Radial Engines". Covington Aircraft. Retrieved October 26, 2019.
• There is a "Pratt & Whitney 1340N Radial Engine" in use on a T-6 Texan at Pacific Warbirds, Oahu, HI