The Gloster Guan was a single-engined single-seat experimental biplane fighter built in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...

to test the performance of fighters using supercharged engines at high altitudes. Three were planned but only two constructed.

Development

The power output of piston engines falls with altitude because of the falling oxygen density. As a result, performance falls away and the operational ceiling is limited. Gloster had, with the Gorcock produced an aircraft much faster than its contemporaries and the Guan was designed to use

supercharging In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induc ...

to maintain this performance at height and raise the service ceiling above its competition. Three Guans were ordered by the

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of State ...

in 1925. As in the Gorcock, power came from variants of the

Napier Lion The Napier Lion is a 12-cylinder, petrol-fueled 'broad arrow' W12 configuration aircraft engine built by D. Napier & Son from 1917 until the 1930s. A number of advanced features made it the most powerful engine of its day and kept it in produ ...

broad arrow A broad arrow, of which a pheon is a variant, is a stylised representation of a metal arrowhead, comprising a tang and two barbs meeting at a point. It is a symbol used traditionally in heraldry, most notably in England, and later by the Britis ...

12-cylinder engine. The first Guan had the 450 hp (335 kW) geared Lion IV; the second the ungeared 525 hp (475 kW) Lion VI. A projected third aircraft would have had an inverted Lion, known as the Lioness, but this machine was not built. These engines had their exhaust-driven supercharger (a concept nowadays known as

turbocharger In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...

) mounted on the nose under the propeller, with much exposed pipework. The radiator was mounted under the fuselage and between the undercarriage legs. Initially these engines drove two-blade fixed-pitch airscrews, but the first aircraft was later fitted with a metal variable-pitch constant-speed propeller. The Guan was a single-bay biplane with wooden, fabric-covered wings of unequal span and marked stagger. All

Folland Folland is a surname. Notable people with the surname include: *Alison Folland (born 1978), American actress and filmmaker * Gerald Folland (born 1947), American mathematician * Henry Folland (1889–1954), British aviation engineer and aircraft de ...

's Gloster fighters from the

Grebe Grebes () are aquatic diving birds in the order Podicipediformes . Grebes are widely distributed freshwater birds, with some species also found in marine habitats during migration and winter. Some flightless species exist as well, most notably ...

onwards had used a thick upper wing in combination with a fairly thin lower wing and the Guan followed this pattern, chosen to provide low drag at high speed with good lift at low, take-off speeds. It had parallel interplane struts and ailerons on all wings. The fuselage was all-metal and fabric covered. The rear fuselage was closer in design to that of the

Gamecock A cockfight is a blood sport, held in a ring called a cockpit. The history of raising fowl for fighting goes back 6,000 years. The first documented use of the ''word'' gamecock, denoting use of the cock as to a "game", a sport, pastime or ente ...

than the Grebe or Gorcock, and the empennage was almost identical to that of the Gamecock. The first aircraft went to

RAE Farnborough The Royal Aircraft Establishment (RAE) was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence (MoD), before finally losing its identity in me ...

in August 1926 and the second followed early in the next year. Supercharging delivered the anticipated performance enhancements, with full power and a top speed of 175 mph (280 km/h) at 15,000 ft (4,570 m). Service ceiling was 31,000 ft (9,450 m) compared with 24,000 ft (7,315 m) for the similarly-powered but slightly smaller-span Gorcock. The fast-spinning turbo-superchargers gave continual trouble. This led to the cancellation of the third Guan and the whole development programme.

The name

Gloster's search for alliterative bird names took them far and wide.

Guan Guan may refer to: * Guan (surname), several similar Chinese surnames ** Guān, Chinese surname * Guan (state), ancient Chinese city-state * Guan (bird), any of a number of bird species of the family Cracidae, of South and Central America * Guan ( ...

is the local name for one of several genera of game-birds of the family ''Cracidae'', which live in tropical America.

Development

The name

Specifications (second Guan)

Notes

References