Initially asked in 1914 to study an overheating problem in rotary engines, Captain W. O. Bentley, an established car designer, developed a new and more efficient engine, with a weight-saving effect realized by careful design and the use of aluminum wherever possible. Equally important was the lower cost, as compared to the French Clerget, then widely used in British aircraft; and itself considered an improvement over the earlier Gnome
The initials A. R. 1 stood for Admiral Rotary 1, and was later renamed Model B. R. 1 for Bentley Rotary 1. The Humber Company of Coventry, England was the first to build the B. R. 1, and a larger model, known as the B. R. 2, was also manufactured by other firms. The A. R. 1 was used on aircraft such as the Sopwith F.1 Camel, Sopwith 7 F.1 Snipe, and Avro 504K.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
1917
United Kingdom
PROPULSION-Reciprocating & Rotary
Humber Ltd. (Coventry, England)
W. O. Bentley
Type: Rotary, 9 cylinders, air-cooled
Power rating: 112 kW (150 hp) at 1,250 rpm
Displacement: 17.3 L (1053 cu in.)
Bore and Stroke: 120 mm (4.72 in.) x 170 mm (6.69 in.)
Weight: 184 kg (405 lb)
Diameter 107 cm (42 in.), Length 111 cm (43.5 in.)
A19270007000
Transferred from the U.S. Navy Department, Washington, D.C.
National Air and Space Museum
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