The Armstrong Siddeley Mongoose is a British five-cylinder radial

aero engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...

produced by Armstrong Siddeley. Developed in the mid-1920s it was used in the Hawker Tomtit trainer and Parnall Peto seaplane amongst others. With a displacement of 540 cubic inches (9 litres) the Mongoose had a maximum power output of 155 horsepower (115 kilowatts). A Mongoose engine powers the sole remaining airworthy Hawker Tomtit, based at Old Warden.

Design and development

The Mongoose is a five-cylinder, single-row, air-cooled radial piston engine. The engine features twin forward-mounted

ignition magneto An ignition magneto, or high-tension magneto, is a magneto that provides current for the ignition system of a spark-ignition engine, such as a petrol engine. It produces pulses of high voltage for the spark plugs. The older term ''tension'' ...

s and enclosed valve rockers, the

cylinders A cylinder (from ) has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infini ...

being the same as those used for the earlier

Jaguar The jaguar (''Panthera onca'') is a large cat species and the only living member of the genus '' Panthera'' native to the Americas. With a body length of up to and a weight of up to , it is the largest cat species in the Americas and the th ...

engine. An unusual feature of the Mongoose is the vertical position of the lower cylinder, a design thought likely to promote oil fouling of the

spark plug A spark plug (sometimes, in British English, a sparking plug, and, colloquially, a plug) is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/air ...

s.Lumsden 2003, p. 69. Built in several variants, power output ranged between 135 and 155 hp (100-115 kW).

Variants

;Mongoose I :1926, 135 hp. ;Mongoose II :1930, 155 hp. ;Mongoose III :1929. ;Mongoose IIIA :1929, civil use. ;Mongoose IIIC :1929, Military use based on IIIA.

Applications

''Note:'' * Avro 504N * Avro 504R * Avro Tutor * Avro Type 621 Trainer *

Handley Page Hamlet __NOTOC__ The Handley Page HP.32 Hamlet was a British six-passenger monoplane transport designed and built by Handley Page.Jackson 1973, p320-321 Only one was built to order of the Air Ministry, first flown with three-engines, later changed to tw ...

* Handley Page Gugnunc * Hawker Tomtit * Parnall Peto * Fokker S.IV

Survivors

An Armstrong Siddeley Mongoose IIIC powers the sole remaining airworthy Hawker Tomtit, ''K1786/G-AFTA'', owned and operated by the Shuttleworth Collection this aircraft flies regularly throughout the summer months.The Shuttleworth Collection - Hawker Tomtit
Retrieved: 22 February 2012

Specifications (Mongoose I)

References

Notes

Bibliography

* Gunston, Bill. ''World Encyclopaedia of Aero Engines''. Cambridge, England. Patrick Stephens Limited, 1989. * Lumsden, Alec. ''British Piston Engines and their Aircraft''. Marlborough, Wiltshire: Airlife Publishing, 2003. .

External links

{{Armstrong Siddeley aeroengines Aircraft air-cooled radial piston engines Mongoose 1920s aircraft piston engines