ABC Scorpion

Scorpion
300px
Scorpion II installed in an ANEC II at the Shuttleworth Collection
Type	Flat-twin aero engine
National origin	England
Manufacturer	ABC Motors Limited
Designed by	Granville Bradshaw
First run	1921

The ABC Scorpion is a 30 hp (22 kW) two-cylinder aero engine designed by the noted British engineer Granville Bradshaw for use in light aircraft. The engine was built by ABC Motors Limited and first ran in 1921.

Variants

Scorpion I

1923, 30 hp (22 kW)

Scorpion II

1924, 34 hp (25 kW), increased bore and stroke.

Applications

• ABC Robin
• Boulton Paul Phoenix
• BFW M.19
• BFW M.23
• Comper Swift
• de Havilland Humming Bird
• Farman Moustique
• Hawker Cygnet
• Heath Parasol
• Hendy Hobo
• Henderson-Glenny Gadfly

• Kay Gyroplane
• Luton Minor
• Mignet HM.14 Pou-du-Ciel
• Parmentier Wee Mite
• RWD 1
• SAI KZ I
• Short Satellite
• Snyder Buzzard
• Wheeler Slymph
• Westland Woodpigeon

Survivors

The only ANEC II (G-EBJO) flies regularly at the Shuttleworth Collection at Old Warden and is powered by a Scorpion II.

Specifications (Scorpion I)

Data from Lumsden

General characteristics

• Type: 2 cylinder air cooled flat-twin
• Bore: 3.6 in (87.5 mm)
• Stroke: 3.7 in (91.5 mm)
• Displacement: 73.32 cu in (1.1 L)
• Dry weight: 90 lb (41 kg)

Components

• Valvetrain: Overhead valve, two valves per cylinder
• Fuel system: Carburettor
• Fuel type: 74 Octane petrol
• Cooling system: Air

Performance

• Power output: 30 hp (22 kW) at 2,750 rpm
• Compression ratio: 4:1
• Power-to-weight ratio: 0.33 hp/lb (0.53 kW/kg)

See also

Comparable engines

• Aeronca E-113
• Armstrong Siddeley Ounce
• Bristol Cherub
• Walter Atom

Related lists

• List of aircraft engines

References

Bibliography

• Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9
• Guttery, T.E. The Shuttleworth Collection. London: Wm. Carling, 1969. OCLC 19614929
• Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.