The Cosmos Mercury was a fourteen-cylinder twin-row air-cooled radial aeroengine. Designed by

Roy Fedden Sir Alfred Hubert Roy Fedden MBE, FRAeS (6 June 1885 – 21 November 1973) was an engineer who designed most of Bristol Engine Company's successful piston aircraft engine designs. Early life Fedden was born in the Bristol area to fairly weal ...

of Cosmos Engineering, it was built in the United Kingdom in 1917. It produced 347 horsepower (259 kW). It did not enter production; a large order was cancelled due to the

Armistice An armistice is a formal agreement of warring parties to stop fighting. It is not necessarily the end of a war, as it may constitute only a cessation of hostilities while an attempt is made to negotiate a lasting peace. It is derived from t ...

Design and development

Built at

Bristol Bristol () is a City status in the United Kingdom, cathedral city, unitary authority area and ceremonial county in South West England, the most populous city in the region. Built around the River Avon, Bristol, River Avon, it is bordered by t ...

by Brazil-Straker under the direction of Roy Fedden, the Mercury featured an unusual

crankshaft A crankshaft is a mechanical component used in a reciprocating engine, piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating Shaft (mechanical engineering), shaft containing one or more crankpins, ...

and

connecting rod A connecting rod, also called a 'con rod', is the part of a reciprocating engine, piston engine which connects the piston to the crankshaft. Together with the crank (mechanism), crank, the connecting rod converts the reciprocating motion of the p ...

arrangement that dispensed with the more normal design of a single master rod linking to individual rods for each cylinder. It was said to run well without vibration and set an unofficial time to climb record while fitted to a Bristol 21A Scout F.1, the aircraft achieving 10,000 ft (3,000 m) in 5.4 minutes and 20,000 ft (6,000 m) in 16.25 minutes.Lumsden 2003, p.92. An Admiralty order for 200 engines was placed in 1917 but was later cancelled by Lord Weir due to the end of

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

, it is also stated that Lord Weir had a preference for the ABC Dragonfly.Gunston 1989, p.44. The name was re-used by Fedden for the later nine-cylinder

Bristol Mercury The Bristol Mercury is a British nine-cylinder, air-cooled, single-row, piston radial engine. Designed by Roy Fedden of the Bristol Aeroplane Company it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from ...

radial engine.

Applications

* Bristol Scout F

Specifications (Mercury)

References

Notes

Bibliography

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

External links

* Contemporary article on Cosmos Engineering's air-cooled radial engines. Photos of the Mercury are on page 869, and a short technical description is o
page 871

Cosmos Mercury at Aviationarchive.org
{{Cosmos aeroengines 1910s aircraft piston engines Aircraft air-cooled radial piston engines