In 1925, Continental, a successful manufacturer of automotive engines, purchased the rights for a Burt-McCollum single-sleeve valve engine design. Believing this technology might replace poppet valves in aircraft engines, Continental announced the R-790 engine in 1927, incorporating single-sleeve valves initially installed on a Wright 9-cylinder engine. It was never fully tested, but followed by the 7-cylinder R-794, for which five engines were ordered by the U.S. Navy in 1934. It was tested, but did not go into production.
The Navy later sponsored a number of unconventional engine designs; however, few entered production. In the case of the 1939 XR-1740-2 development, the outcome was apparently typical of single-sleeve valve history. For example, Bristol’s Roy Fedden, one of history’s great aircraft engine experts, was unable to mass produce single-sleeve engines. Continental only became successful after reverting to poppet valves, and this artifact represents a seemingly simple new concept that could not compete with older, conventional technology better developed for practical application.
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 1941
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Manufacturer
Continental, Inc.
Physical Description
Type: Reciprocating, 14 cylinders, 2 rows, radial, air-cooled, direct fuel injection, single-speed centrifugal supercharger
Power rating: 652 kW (875 hp) at 2,600 rpm
Displacement: Not available
Bore and Stroke: Not available
Weight: 630 kg (1,388 lb)
Dimensions
Height 134.6 cm (53 in.), Length 176.5 cm (69.5 in.), Width 132.7 cm (52.25 in.)
Materials
Steel, Aluminum, paint, Plastic, Copper, Stainless Steel, Rubber, Magnesium
Inventory Number
A19710891000
Credit Line
Transferred from the U.S. Navy
Data Source
National Air and Space Museum
Restrictions & Rights
Open Access (CCO)
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