About the middle of 1923, the U.S. Navy signed a contract with Wright Aeronautical for three large air-cooled engine designs, which were to be built successively. The first of these, based on a design proposed earlier to the U.S. Army by Charles Lawrance, was known as the P-1, and was the direct forerunner of the highly successful Wright Cyclone series of engines. In order to reduce aerodynamic drag, its design was limited to a frontal area no greater than that of the Navy's Lawrance J engine, despite the fact that the P-1 had twice the displacement.
The P-1 was tested extensively in 1924 in a Douglas DT-2 aircraft, and flown successfully in the Navy Douglas DT-6 and Boeing aircraft. However, magnesium alloy castings, being used for the first time, failed in endurance tests. The P-1 was then discontinued in favor of the larger P-2, which added Heron-type cylinders and a supercharger.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Date
Circa 1925
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Manufacturer
Wright Aeronautical
Physical Description
Type: Reciprocating, 9 cylinders, radial, air cooled
Power rating: 303 kW (406 hp) at 1,650 rpm
Displacement: 27.1 L (1,654 cu in.)
Bore and Stroke: 152 mm (6.0 in.) x 165 mm (6.5 in.)
Weight (dry): 368 kg (812 lb)
Dimensions
Diameter 121.9 cm (48 in.), Length 116.8 cm (46 in.)
Materials
Steel, Aluminum, Brass, Copper, Cadmium plating, Paint, Preservative coating, Magnesium, Rubber
Inventory Number
A19710881000
Credit Line
Transferred from the U.S. Navy
Data Source
National Air and Space Museum
Restrictions & Rights
Open Access (CCO)
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