| Genet Major/Civet | |
|---|---|
![]()  | |
| Genet Major installed in a Southern Martlet at the Shuttleworth Collection | |
| Type | Radial aero engine | 
| Manufacturer | Armstrong Siddeley | 
| First run | 1928 | 
| Developed from | Armstrong Siddeley Genet | 
The Armstrong Siddeley Genet Major is a British five-cylinder (later seven-cylinder), air-cooled, radial engine for aircraft, designed and built by Armstrong Siddeley and first run in 1928. It developed 140 horsepower (104 kW). In Royal Air Force use the seven-cylinder version was known as the Civet I. The Feliform names used are in line with company convention, the Genet and Civet[1] both being large cat-like carnivores.
Variants and applications
Genet Major I
The Genet Major 1 was a five-cylinder engine of 105 horsepower (78 kW) that was closely related to the Genet I but with increased bore and stroke.
Genet Major 1A (Civet I)

The Genet Major 1A (or Civet I in RAF service) was a seven-cylinder development of the Genet Major I, nominally rated at 145 horsepower (108 kW).
- ANBO V (upgrade)
 - Avro Avian
 - Avro Cadet
 - Avro Rota
 - Cierva C.30A Autogiro
 - RWD-6 (not specified 7-cylinder Genet Major sub-type)
 - Saro Cutty Sark
 - SEA-1
 - Westland Wessex
 
Genet Major III
As Genet Major IA but with cylinders using cast rocker boxes.
Genet Major IV
A geared propeller drive version of the Genet Major IA, 160 horsepower (120 kW).
Surviving engines
An Armstrong Siddeley Genet Major powers Southern Martlet (G-AAYX) which is owned and operated by the Shuttleworth Collection at Old Warden and flies at home air displays throughout the summer months.[2] An Armstrong Siddeley Genet Major 1A engine also powers the only surviving Civilian Aircraft Co.Ltd. 1931 vintage Civilian Coupe 02 monoplane (G-ABNT), which is airworthy and owned and operated by Shipping and Airlines Ltd based at Biggin Hill Airport, England.
Engines on display
- An Armstrong Siddeley Genet Major IA is on display at the Royal Air Force Museum Cosford.[3]
 - An Armstrong Siddeley Genet Major IV can be seen in Polish Aviation Museum in Cracow.[4]
 - Aviation Heritage Museum (Western Australia)[5]
 
Specifications (Genet Major IA/Civet I)
Data from Lumsden[6]
General characteristics
- Type: 7-cylinder single-row radial piston engine
 - Bore: 4.25 in (107.95 mm)
 - Stroke: 4.5 in (114.3 mm)
 - Displacement: 452.01 cu in (7.3 L)
 - Length: 38.8 in (985.5 mm)
 - Diameter: 38.15 in (970 mm)
 - Dry weight: 327 lb (148 kg)
 
Components
- Valvetrain: Overhead poppet valves
 - Fuel type: 77 Octane petrol
 - Cooling system: Air-cooled
 - Reduction gear: Direct drive, Left hand tractor
 
Performance
- Power output: 165 hp (123 kW) at 2,425 rpm at sea level
 - Compression ratio: 5:1
 - Power-to-weight ratio: 0.5 hp/lb
 
See also
Related development
Comparable engines
Related lists
References
Notes
- ↑ Lumsden 2003, p.71.
 - ↑ The Shuttleworth Collection - Southern Martlet Archived 17 February 2018 at the Wayback Machine Retrieved: 21 November 2017
 - ↑ Royal Air Force Museum Cosford - Armstrong Siddeley Genet Major 1A 'Civet' www.rafmuseum.org.uk Retrieved: 1 January 2014
 - ↑ "Zbiory - silniki lotnicze". Muzeum Lotnictwa Polskiego (Polish Aviation Museum) (in Polish). Polish Aviation Museum.
 - ↑ Aviation Heritage Museum
 - ↑ Lumsden 2003, p.71
 
Bibliography
- Gunston, Bill (1986). World Encyclopedia of Aero Engines. Wellingborough: Patrick Stephens. p. 18.
 - Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.
 
