Wolseley Viper

Viper
Rear view of preserved Wolseley Viper
Type	Piston inline aero-engine
Manufacturer	Wolseley Motors
First run	1918
Major applications	Royal Aircraft Factory S.E.5

The Wolseley Viper is a British-built, high-compression derivative of the Hispano Suiza HS-8 liquid-cooled V-8 engine, built under licence by Wolseley Motors during World War I.

It powered later models of the S.E.5a, SPAD VII and other British or British-built aircraft designed for the Hispano-Suiza.

Variants

Wolseley W.4A Python I

Wolseley W.4A Python II

Wolseley W.4A Viper

Wolseley W.4B Adder I

Wolseley W.4B Adder II

Wolseley W.4B Adder III

Wolseley W.4A Python

Applications

• Airco DH.9
• Avro 552
• Bristol M.R.1
• Bristol Tourer
• Cierva C.8
• Martinsyde F.6
• Royal Aircraft Factory S.E.5a
• Sopwith Antelope
• Sopwith Cuckoo

Survivors

A Wolseley Viper powered Royal Aircraft Factory S.E.5a is owned by, and on display at The Shuttleworth Collection, Old Warden Aerodrome in the UK.^[1]

Engines on display

• A preserved Wolseley Viper is on public display at the Science Museum, London.
• A preserved Wolseley Viper is on public display at the Museo Nacional de Aeronáutica de Argentina

Specifications (W.4A Viper)

Data from Lumsden^[2]

General characteristics

• Type: 8-cylinder, upright, 90 degree Vee engine
• Bore: 4.72 in (120 mm)
• Stroke: 5.12 in (130 mm)
• Displacement: 716.8 cu in (11.77 L)
• Dry weight: 500 lb

Components

• Fuel system: Twin Zenith-Duplex carburettors
• Cooling system: Liquid-cooled
• Reduction gear: Direct drive, Right-hand tractor

Performance

• Power output: 200 hp at 2,000 rpm (takeoff power)
• Compression ratio: 5.3:1

See also

Related development

• Hispano-Suiza 8

Comparable engines

• Sunbeam Arab

Related lists

• List of aircraft engines

References

Wikimedia Commons has media related to Wolseley Viper.