Rolls-Royce Exe

{{Infobox aircraft begin

|name= Exe

|image= File:RRExe.JPG

|caption=

}}{{Infobox aircraft engine

|type=Piston X-24 aero-engine

|national origin= United Kingdom

|manufacturer=Rolls-Royce Limited

|first run=September 1936

|major applications=Fairey Battle

|number built =

|program cost =

|unit cost =

|developed from =

|developed into = Rolls-Royce Pennine

|variants with their own articles =

}}

The Rolls-Royce Exe, or Boreas,This name was dropped due to conflict with the Bristol Aeroplane Company's series of Greek mythology named engines, Lumsden 2003, p.201. was a 24-cylinder air-cooled X block sleeve valve aircraft engine intended primarily for the new Fairey Fleet Air Arm aircraft, particularly the Fairey Barracuda. The Exe was relatively powerful for its era, producing about {{Convert|1,100|hp|kW|abbr=on}}. This is notable given the relatively small {{convert|22|litre|cuin|order=flip}} displacement, the Merlin requiring {{convert|27|litre|cuin|order=flip}} for approximately the same power level. The X-24 layout made this quite a compact engine.

The Exe was named after the River Exe, although Rolls-Royce later transferred the use of river names to its gas turbine engines.

Design and development

The Exe was under development in 1939, having been started in the 1930s, along with the Peregrine and Vulture. Work on the Exe was suspended in August 1939,Lloyd 1978, p4-5. and stopped about August 1940.Pugh 2000, p.263-265. Ernest Hives, head of the Rolls-Royce aero engine division, wanted to stop work on the Exe, Peregrine, and Vulture to concentrate on the Merlin and Griffon engines. An enlarged version, the Rolls-Royce Pennine, was built later in the war, but cancelled as jet engines became the company's focus.

Originally intended for the Supermarine Type 322 and Fairey Barracuda the Exe was only test flown in a Fairey Battle, the first flight taking place on 30 November 1938. This aircraft continued in use for some time as a communications aircraft where the Exe was noted to be quite reliable in service.Rubbra 1990, p.148.

==Applications==

Fairey Barracuda (intended)
Fairey Battle (testbed)
Supermarine Type 322 (intended)

Specifications (Exe)

{{pistonspecs

|ref=Gunston and Lumsden.Gunston 1989, p. 142.Lumsden 2003, p.201.

|type=24-cylinder supercharged air-cooled 90-degree X layout aircraft piston engine

|bore={{convert|4.225|in|mm|abbr=on}}

|stroke={{convert|4.0|in|mm|abbr=on}}

|displacement={{convert|1,348|in3|L|abbr=on}}

|length=

|diameter=

|width=

|height=

|weight={{convert|1,530|lb|kg|abbr=on}}

|valvetrain=Sleeve valve

|supercharger=Gear-driven centrifugal type supercharger, single stage

|turbocharger=

|fuelsystem=

|fueltype=Petrol

|oilsystem=

|coolingsystem=Pressure air-cooled

|power={{convert|1,150|hp|kW|abbr=on}} at 4,200 rpm, +4.5 psi boost at sea level

|specpower=

|compression=8:1

|fuelcon=

|specfuelcon=

|oilcon=

|power/weight={{convert|0.75|hp/lb|kW/kg|abbr=on}}

|reduction_gear=0.358:1, left hand tractor

|general_other=

|components_other=

|performance_other=

}}

References

=Notes=

=Bibliography=

Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. {{ISBN|1-85260-163-9}}
Lloyd, Ian Rolls-Royce: The Merlin at War (1978, Macmillan London) {{ISBN|0-333-24016-2}}
Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. {{ISBN|1-85310-294-6}}.
Pugh, Peter.The Magic of a Name: The Rolls-Royce Story, The first 40 Years (2000, Icon Books Cambridge) {{ISBN|1-84046-151-9}}
Rubbra, A.A. Rolls-Royce Piston Aero Engines - a designer remembers: Historical Series no 16 :Rolls-Royce Heritage Trust, 1990. {{ISBN|1-872922-00-7}}

External links

[http://www.stobbe.dk/library/engines/rolls_royce/images/rr-exe.jpg Photo of the Rolls-Royce Exe]
[http://www.flightglobal.com/pdfarchive/view/1948/1948%20-%200146.html The Exe-engined Fairey Battle (top picture)] in a 1948 issue of Flight

Exe

Category:1930s aircraft piston engines

Category:X engines