Armstrong Siddeley Genet Major

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.

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

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.

• Avro Avian
• Avro 619
• Avro 624
• Avro 638 Club Cadet
• Cierva C.19 Autogiro
• Civilian Coupé
• Saro Cutty Sark
• Southern Martlet
• Westland IV

Genet Major 1A (Civet I)

Armstrong Siddeley Civet

Armstrong Siddeley Genet Major IV on display at the Polish Aviation Museum

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).

• ANBO 51

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 Kraków.^[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

• Armstrong Siddeley Genet

Comparable engines

• Warner Scarab

Related lists

• List of aircraft engines