| 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.[1]
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.[2]
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

- 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
 - 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[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.[4][5][6][7]
 
Specifications (R-1340-S1H1-G)

Data from Jane's.[8]
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
Related development
- Pratt & Whitney R-985 Wasp Junior
 - Pratt & Whitney R-1535 Twin Wasp Junior
 - Pratt & Whitney R-1830 Twin Wasp
 
Related lists
References
Notes
- ↑ Pratt&Whitney R-1340 page Retrieved: 25 October 2008
 - ↑ "Pratt’s first engine gets historic designation" from Hartford Business Journal, published February 1st Retrieved: 7 April 2016
 - ↑ "Knoll KN-3". Western Flying. August 1929.
 - ↑ http://neam.org/index.php?option=com_content&view=article&layout=edit&id=1119 "Pratt & whitney R-1340 Wasp A"
 - ↑ http://neam.org/index.php?option=com_content&view=article&layout=edit&id=1113 "Pratt & Whitney R-1340 Wasp C Cutaway"
 - ↑ http://neam.org/index.php?option=com_content&view=article&layout=edit&id=1120 "Pratt & Whitney R-1340-0 Wasp C"
 - ↑ http://neam.org/index.php?option=com_content&view=article&layout=edit&id=1122 "Pratt & Whitney Roscoe Turner R-1340 Wasp Engine"
 - ↑ Bridgman 1994, p. 81d.
 
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
 
