Fairey Gyrodyne
| Fairey Gyrodyne | |
|---|---|
|
|
| Type: | Helicopter |
| Design country: | |
| Manufacturer: | |
| First flight: |
December 7, 1947 |
| Commissioning: |
Development canceled in 1949 |
| Number of pieces: |
2 |
The Fairey FB-1 Gyrodyne was an experimental helicopter made by the British manufacturer Fairey Aviation. "FB" stood for "Fairey-Bennett". The Gyrodyne used a single rotor for vertical take-off and landing, as well as a pulling propeller for propulsion, which, attached to the right-hand stub wing, also took over the torque compensation. Gyrodyne is a combination of gyratory (rotating) and aerodyne, a term for aircraft heavier than air , in contrast to aerostats .
history
In April 1946, Fairey announced a self-financed project of a flying helicopter that would be designed and built to a design by JAJ Bennett. The plans for this were drawn up by Bennett as the technical director of the Cierva Autogiro Company at the time between 1936 and 1939. The design, known as Cierva C.41 Gyrodyne , was successfully submitted to the invitation to tender p. 22/38 for a helicopter of the Royal Navy . With the beginning of the Second World War, however, the development was stopped and even after the end of the war, Weir Ltd., as the owner of Cierva, did not resume the project. Bennett then moved in August 1945 to the newly formed helicopter division of Fairey.
On April 3, 1946, Fairey presented his "private venture" project, the airplane helicopter designed according to the requirements of Specification E.4 / 46. Fairey received an order from the Air Ministry to build two prototypes. Fairey exhibited the almost complete cell of the first prototype at the SBAC show in Radlett (Hertfordshire) in September 1947. The untethered first flight took place on December 7, 1947 at White Waltham Airport, after which a test at slowly increased speeds followed until March 1948. The machine received the aircraft registration G-AIKF and the provisional RAF serial number VX591. The second prototype (G-AJJP) went into trial operation in September 1948.
The first prototype attempted a world record speed record for class G helicopters on a straight 3-kilometer route on June 28, 1948. A Focke-Achgelis Fa 61 held the record for a long time and was only broken shortly before by a Sikorsky R-5 . The Gyrodyne test along the London-Reading railway line was successfully completed with an average speed of 200 km / h. Ten months later, in April 1949, preparations for a record attempt over the closed 100-kilometer course had to be broken off due to the crash of the machine. The pilot Foster H. Dixon and the observer Derek Garraway died in the accident.
By this time the Gyrodyne had already prevailed against the competitors Westland / Sikorsky Dragonfly and Bristol Sycamore and had been selected for use with the British Army in Malaya . Due to the accident, however, development was delayed and the six machines that had been ordered could no longer be delivered. Instead, the Army procured the Dragonfly and later the Sycamore.
During the investigation of the crash, which determined a fatigue fracture of a bolt on the flapping hinge as the cause, the second specimen was banned from starting. After extensive reconstruction and renaming to Jet Gyrodyne , the machine flew again for the first time in January 1954. The drive then differed significantly from that of the first prototype with a blade tip drive of the rotor, as well as cyclic and collective blade adjustment that acted directly on each rotor blade . In addition, two pusher propellers were now planned to generate propulsion. The main task of the Jet Gyrodyne was to acquire data for the Fairey Rotodyne , which is currently under development .
construction
The Gyrodyne had a compact, aerodynamically designed hull. The drive for the rotor and propeller was provided by an Alvis Leonides radial engine, which was installed centrally in the fuselage and was forcibly cooled by means of a fan. The distribution of power between the rotor, which is equipped with a swash plate and tiltable hub, and the one propulsion propeller could be set variably. When hovering and at low forward speed, most of the power went to the propeller, so that it could take over both control around the yaw axis and propulsion. In level flight, the separate propeller drive made it possible to operate with lower rotor blade pitch angles and less load on the circular area , which in turn enabled higher speeds compared to helicopters. As an indication of the complexity of the entire system, it can be pointed out that almost 50% of the curb weight was accounted for by the drive and the power transmission systems.
The aerodynamic fairing at the end of the left stub wing only formed the housing for a battery, which was moved there to maintain the center of gravity.
Technical specifications
| Parameter | Data |
|---|---|
| crew | 1 |
| Passengers | 4 to 5 |
| length | 5.84 m |
| Rotor diameter | 15.85 m |
| height | 3.07 m |
| Empty mass | 1633 kg |
| Max. Takeoff mass | 2177 kg |
| Top speed | 225 km / h |
| Service ceiling | 3050 m |
| Range | 400 km |
| Engines | an Alvis Leonides nine-cylinder radial engine to drive the main rotor and a propeller on the right wing |
See also
literature
- HA Taylor: Fairey Aircraft since 1915 , Naval Institute Press, 1974, ISBN 0-87021-208-7 , pp. 388-392
- Fairey Gyrodyne - Design Survey of the World's Fastest Helicopter . In FLIGHT, April 21, 1949, pp. 453–459 ( online )
