Pratt & Whitney R-1340 Wasp C
The Pratt & Whitney R-1340 Wasp was a radial aircraft engine 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).
The Wasp C featured a solid master connecting rod and two piece crankshaft. The master connecting rod has a solid instead of detachable cap big end allowing higher crank speeds. The single trhro two-pice crankshaft is divided into a forward and rear section. The crankpin is integral with the forward section which transmits power to the propeller hub carried by it. The rear section telescopes into the crankpin and is carried completely through it. The two sections are united by a hrough bolt and kept in the proper angular relation by splines.
The main crankcase of forged aluminium is divided into two similar sections in the plane of the cylinder and united by nine through olts between the cylinders as well as by the cylinder flanges.
All valve perating parts are enclosed. The rocker arms are supporte by ball bearngs and are ounted in the rocker housings which are part of the cylinder head. The push rods are enclosed by telescopic covers held in place by springs.
Every Pratt & Whitney engine is provided with a General Electric rotary induction fan used to provide proper mixture distribution. With suitable gear ratio it is possible for certain specialised purposes to provide a reasonable amount of supercharging without additional weight or complication.
All the accessories are grouped at the rear of the engine protected by the cowling.
On geared engines a 2:1 propeller speed reduction is provided by a geared unit of patented Pratt & whiney design, weighing 775 lb.
First run on 29 December 1925, a total of 34,966 engines were produced.
Type: 9 cylinder fixed radial, air cooled
Military Rating: 450 hp at 2100 rpm
Commercial Rating Direct: 420 hp at 2000 rpm
Commercial Rating Geared: 420 hp at 2100 rpm
Displacement: 1344 cu.in
Compression ratio: 5.24-1
Bore: 5 3/4 in
Stroke: 5 3/4 in
Length: 42 9/16 in
Diameter: 51 1/2 in
Weight: 695 lb
Fuel consumption: not more than .55 lb/hp/hr
Oil consumption: not more than .035 lb/hp/hr
Lubrication: Pressure (gear pump) 75-100 lb
Ignition: Scintilla, dual
Carburation: Stromberg, 2 bbls
Spark plugs: B.G.
Price Series C: $7200
Price Series C.G: $8200