RAF 4 explained
The RAF 4 is a British air-cooled, V12 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 Daimler and Siddeley-Deasy. The RAF 5 was a pusher version of the same engine.[1]
Turbocharger
A turbocharged experimental version of the RAF 4, the RAF 4d, was developed using a Rateau exhaust-driven turbocharger. The engine was test-flown in a R.E.8, but the turbocharging experiments were abandoned after the turbine failed on 4 May 1918.[2]
Variants
- RAF 4
1914 - Prototype engine, 140 horsepower (104 kW).
- RAF 4a
1917 - Main production variant, 150 horsepower (112 kW). 3,608 built.
- RAF 4d
1916 - 180 horsepower (134 kW), experimental supercharger installation. 16 built.
- RAF 4e
1917 - 240 horsepower (180 kW), strengthened cylinders and enlarged valves.
- RAF 5
1915 - 150 horsepower (112 kW), pusher version with fan-cooling.
- RAF 5b
170 horsepower (127 kW), increased bore version of RAF 5.Applications
RAF 4
RAF 5
Engines on display
A preserved RAF 4a engine is on public display at the Science Museum (London).
References
Bibliography
- Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989.
- Hare, Paul R. The Royal Aircraft Factory. London: Putnam, 1990.
- Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. .
Notes and References
- Gunston, 1989, p. 156.
- Hare 1990, p. 265
