Napier Cub
{{short description|1910s British aircraft piston engine}}
{{Use dmy dates|date=December 2017}}
{{Use British English|date=December 2017}}
| {{Infobox Aircraft Begin
|name=Cub |image=NapierCub.jpg |caption= Napier Cub rear view. }}{{Infobox Aircraft Engine |type=Piston aero engine |manufacturer=D. Napier & Son |first run=1919 |major applications=Avro Aldershot |number built = 6 |program cost = |unit cost = |developed from = |developed into = |variants with their own articles = }} |
The Napier Cub was an unusual and very large experimental {{Convert|1000|hp|kW|lk=on}} 16-cylinder 'X' pattern liquid-cooled aero engine built by the British engine company D. Napier & Son. The Cub was the only Napier 'X' engine design. First flown on 15 December 1922 in an Avro Aldershot biplane bomber aircraft, the only other application was in the Blackburn Cubaroo. Only six engines of this type were ordered and produced.Lumsden 2003, p.171.
Design
The four banks of four cylinders were arranged in a flattened 'X' when viewed from the front. The angle between the upper cylinders was 52.5 degrees, the lower cylinders 127.5 degrees, which gave an angle of 90 degrees between the outer cylinder banks. The cylinders consisted of separate individual steel forgings with welded steel water cooling jackets. The carburettor was situated below the propeller reduction gear at the front of the engine and fed the inlet valves through four inlet manifolds. The valve drive gear, magnetos and pumps were fitted to the rear of the crankcase.
Specifications (Cub)
{{pistonspecs|
|ref=LumsdenLumsden 2003, p.170.
|type=16-cylinder liquid-cooled X engine
|bore=6.25 in (158.75 mm)
|stroke=7.5 in (190.5 mm)
|displacement=3,681 cu in (60.32 L)
|length=
|diameter=
|width=
|height=
|weight=2,450 lb (1,111 kg)
|valvetrain=Single overhead camshaft with four poppet valves per cylinder
|supercharger=
|turbocharger=
|fuelsystem=Updraught carburettor
|fueltype=Petrol
|oilsystem=
|coolingsystem=Liquid cooled
|power=1,000 hp at 1,800 rpm
|specpower=
|compression=5.3:1
|fuelcon=
|specfuelcon=
|oilcon=
|power/weight=0.4 hp/lb
|designer=
|reduction_gear=Spur geared, reduction ratio 0.489:1, left hand tractor
|general_other=
|components_other=
|performance_other=
}}
See also
{{aircontent
|see also=
|related=
|similar aircraft=
|lists=
|similar engines=
}}
References
=Notes=
{{reflist}}
=Bibliography=
{{refbegin}}
- Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. {{ISBN|1-85310-294-6}}.
{{refend}}
External links
- [http://www.flightglobal.com/pdfarchive/view/1922/1922%20-%200118.html "Harnessing 1,000 Horse Power"] a 1922 Flight article on the Cub
{{Napierengines}}