# Pratt & Whitney R-1340 Wasp

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

* Agusta-Bell AB.102
* Air Tractor AT-301
* Air Tractor AT-401
* Ayres Thrush
* Bach Air Yacht
* Boeing 247
* Boeing F3B
* Boeing F4B
* Boeing Model 40A
* Boeing P-12
* Boeing P-26 Peashooter
* Boeing P-29
* CAC Ceres
* CAC Wirraway
* Curtiss F7C Seahawk
* Curtiss Falcon
* 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 QED
* Gee Bee R 1/2 Super Sportster
* Gee Bee R-1
* Gee Bee R-2 Super Sportster
* Gee Bee YW
* Gee Bee Z
* Goodyear K-class blimp
* Grumman Ag Cat
* Grumman Mallard
* Howard DGA-6
* Ireland N-2C Neptune
* Junkers Ju 52
* Junkers W 34
* Kaman HH-43 Huskie
* Knoll Aircraft Company KN-3
* Lockheed Model 8 Sirius
* Lockheed Model 9 Orion
* Lockheed Model 10-C & 10-E Electra
* Lockheed Vega 5
* 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
* Thomas-Morse XP-13A Viper
* TNCA MTW-1
* 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)

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)