The Cierva C.40 was a British

autogyro An autogyro (from Greek and , "self-turning"), also known as a ''gyroplane'', is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. Forward thrust is provided independently, by an engine-driven propeller. Whi ...

designed by G.B.L. Ellis, Otto Reder, and Dr. J.A.J Bennett and was assembled by the British Aircraft Manufacturing Company at London Air Park, Hanworth.

Development

The C.40 was the last autogiro produced by the

Cierva Autogiro Company The Cierva Autogiro Company was a British firm established in 1926 to develop the autogyro. The company was set up to further the designs of Juan de la Cierva, a Spanish engineer and pilot, with the financial backing of James George Weir, a Scotti ...

, Ltd. Design commenced in July 1936 and continued after Cierva's death in an airliner crash in December of that year. Based on the C.30A Autogiro the C.40 was originally intended to use a higher power version of the

Armstrong Siddeley Genet Major The Armstrong Siddeley Genet Major is a British five-cylinder (later seven-cylinder), air-cooled, radial engine for aircraft, designed and built by Armstrong Siddeley and first run in 1928. It developed 140 horsepower (104 kW). In Royal A ...

engine. Utilizing the lessons of autodynamic rotor development underway since 1933, the C.40 rotor included three flexible blades to suppress vibration and were attached to the rotor hub through inclined flap and drag hinges to give jump-takeoff capability. It had two side-by-side seats in a wooden fuselage and the production version was powered by a Salmson 9NG radial engine, problems with which delayed introduction of the C.40 into service until mid-1938.

Operational history

In 1938 the British Aircraft Manufacturing Company assembled nine C.40s at London Air Park, Hanworth, and seven were delivered to the

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...

. The remaining two were registered to the Cierva Autogiro Company, one was lost in France in June 1940, and the other was impressed into RAF service.

Operators

; *

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...

Specification

References

Notes

Bibliography

* * {{Cierva aircraft Single-engined tractor autogyros 1930s British military utility aircraft C.40