ABC 8 hp

The ABC 8 hp is an 8 hp (6 kW) two-cylinder aero engine designed by the noted British engineer Granville Bradshaw for use in ultralight aircraft. The engine was derived from a specially tuned motorcycle unit and was built by ABC Motors, first running in 1923.^[1]

8 hp
ABC 8 hp installed in the English Electric Wren at the Shuttleworth Collection
Type	Flat-twin aero engine
National origin	United Kingdom
Manufacturer	ABC Motors Limited
Designer	Granville Bradshaw
First run	1923

Applications

• English Electric Wren
• Handley Page H.P.22
• Pegna-Bonmartini Rondine

Surviving engines

The sole surviving English Electric Wren (G-EBNV) flies occasionally at the Shuttleworth Collection at Old Warden and is powered by an ABC 8 hp engine. With barely enough power to maintain flight the aircraft is assisted into the air by a team of volunteers using bungee cord, after which the Wren lands straight ahead following a short 'hop'.^[2]

Specifications (ABC 8 hp)

Data from Lumsden^[3]

General characteristics

• Type: 2-cylinder air-cooled flat-twin
• Bore: 2.72 in (69 mm)
• Stroke: 2.13 in (54 mm)
• Displacement: 24.76 cu in (404 cc)
• Dry weight: 41 lb (18.6 kg)

Components

• Valvetrain: Overhead valve, two valves per cylinder
• Fuel system: Carburettor
• Fuel type: Petrol
• Cooling system: Air-cooled

Performance

• Power output: 8 hp (6 kW) at 4,500 rpm
• Power-to-weight ratio: 0.2 hp/lb (0.32 kW/kg)

See also

• ABC motorcycles

Related development

• ABC Scorpion

Comparable engines

• Armstrong Siddeley Ounce
• Bristol Cherub
• Walter Atom

Related lists

• List of aircraft engines