RAF 3

RAF 3
RAF 3a on display at the Polish Aviation Museum
Type Piston inline aero engine
National origin United Kingdom
Manufacturer Royal Aircraft Factory
First run September 1914
Major applications Royal Aircraft Factory R.E.7
Number built 289
Developed from RAF 1
Developed into RAF 4

The RAF 3 is a British liquid-cooled, V-12 engine developed for aircraft use during World War I. Based on the eight–cylinder RAF 1 it was designed by the Royal Aircraft Factory but produced by the two British companies of Armstrong Whitworth and Napier & Son. The RAF 7 was a high compression version of the same engine.[1]

Variants

RAF 3
1914 - Prototype engine, 200 horsepower (150 kW).
RAF 3a
1914 - Main production variant, increased bore, 260 horsepower (194 kW). 29 built by Armstrong Whitworth, 260 built by Napier & Son.
RAF 7
300 horsepower (224 kW) high compression version with high-lift camshafts.

Applications

Specifications (RAF 3a)

Data from Lumsden[2]

General characteristics

  • Type: 12-cylinder, upright, 60-degree Vee engine
  • Bore: 4.5 in (114.3 mm)
  • Stroke: 5.5 in (140 mm)
  • Displacement: 1,049.4 cu in (17.24 L)
  • Dry weight: 780 lb (354 kg)

Components

  • Valvetrain: Overhead valve, both valves operated by a single pushrod
  • Cooling system: Liquid-cooled
  • Reduction gear: 0.5:1, left-hand tractor

Performance

See also

Related development

Comparable engines

Related lists

References

Notes

  1. ^ Gunston, 1989, p. 156.
  2. ^ Lumsden 2003, p. 223.

Bibliography

Wikimedia Commons has media related to RAF 3.
  • Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9
  • Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.