Humber Ltd. (Bentley) B.R.2, Rotary 9 Engine
date: label: Date
content: ca. 1917
name: label: Manufacturer
content: Humber Ltd. (Coventry, England)
label: Designer
content: W. O. Bentley
notes: label: Physical Description
content: Type: Rotary, 9 cylinders, air-cooled
label: Physical Description
content: Power rating: 149 kW (200 hp) at 1,300 rpm
label: Physical Description
content: Displacement: 25.0 L (1,522.44 cu. in.)
label: Physical Description
content: Bore and Stroke: 140 mm (5.51 in) x 190 mm (7.09 in)
label: Physical Description
content: Weight (dry): Approx 227 kg (500 lb)
label: Summary
content: 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
label: Summary
content: Following success of the smaller A.R.1 (Admiral Rotary 1), which was later renamed Model B.R.1 for Bentley Rotary 1, the larger B.R.2 rotary aircraft engine powered a variety of World War I aircraft, including, among others, the: Sopwith F.1 Camel and 7F.1 Snipe; Nieuport B.N.1; and Vickers F.B.26A Vampire II. Humber Ltd., one of five British companies that manufactured this model during World War I, built this Bentley B.R.2 artifact.
place: label: Country of Origin
content: United Kingdom
setName: label: See more items in
content: National Air and Space Museum Collection
label: Location
content: National Air and Space Museum in Washington, DC
label: Exhibition
content: World War I: The Birth of Military Aviation
creditLine: label: Credit Line
content: Gift of Preston Kirk
dataSource: label: Data Source
content: National Air and Space Museum
identifier: label: Inventory Number
content: A19570999000
objectType: label: Type
content: PROPULSION-Reciprocating & Rotary
objectRights: label: Restrictions & Rights
content: CC0
physicalDescription: label: Materials
content: Metal
label: Dimensions
content: 3-D: 101.6 × 157.5 × 104.1cm, 336.6kg (3 ft. 4 in. × 5 ft. 2 in. × 3 ft. 5 in., 742lb.)
label: Dimensions
content: Support: 71 × 108 × 79cm (2 ft. 3 15/16 in. × 3 ft. 6 1/2 in. × 2 ft. 7 1/8 in.)