Charles Lawrance designs for air-cooled engines began in 1915. In 1921, his own small company’s J-1 149 kW (200 hp) engine was designed for a Navy contract. Wanting a better, compact, lightweight engine not plagued with water leakage problems for use on aircraft carriers; the Navy encouraged the 1923 merger with the larger Wright Aeronautical Corporation. The Lawrance engine then progressed through the Wright Whirlwind J-3, J-4, J-5, and J-6 series, with the fully supercharged, high compression R-760-E2 certificated in December 1935. However, the most famous of these models was the J-5 which powered Lindbergh’s Spirit of St. Louis.

The first model in the seven-cylinder Wright Whirlwind R-760 (J-6) series was certificated in 1929. The J-6 powered aircraft such as the Stinson SM-2AC, Waco CRG/CSO, Curtiss-Wright CW Sedan 15-D, Curtiss-Wright Travel Air 4-D/10-2. Other R-760 engines powered aircraft such as the St. Louis PT-15, Howard UC-70C, Fairchild UC-88, Fairchild JK-1, Fairchild F-45, and Naval Aircraft Factory N3N-1/-3.

 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 1926 Country of Origin United States of America Type PROPULSION-Reciprocating & Rotary Manufacturer Wright Aeronautical
 Physical Description Type: Reciprocating, 7 cylinders, radial, air-cooled Power rating: 239 kW (320 hp) at 2,200 rpm Displacement: 12.39 L (755.93 cu in.) Bore and Stroke: 127 mm (5.0 in.) x 139.7 mm (5.5 in.) Weight (dry): 259 kg (570 lb) Dimensions Length 114.3 cm (45 in.), Width 114.3 cm (45 in.), Height 114.3 cm (45 in.)
 Materials Aluminum
Steel
Leather
Paint
Copper Alloy
Rubberized Fabric
Felt
Paper
Magnesium Alloy
 Inventory Number A19660462000 Credit Line Found in the collection Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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