The Fairey Rotodyne
This article, excerpted from a study produced by Dr. Frank Anders in
1988, and reproduced in part here, relates how the problem of gridlock
at major hubs was evaluated, attacked, and solved in 1957.
Fairey Rotodyne originated from an idea for a large compound helicopter
by Dr. J. A. J. Bennett and Capt. A. G. Forsyth of Fairey Aviation,
whose original study dates back to 1947. Their concept evolved into
the "Eland" Rotodyne prototype, which sucessfully completed
its maiden flight in November, 1957. Its four-bladed rotor was powered
in helicopter mode by tip jets, driven by compressed air. This compressed
air was lit with fuel at tip jet combustion chambers to drive the
rotor, removing the necessity for an anti-torque tail rotor. The
tip jets were extinguished at about 60 mph after a normal helicopter
takeoff, converting the aircraft to an autogiro. In autogiro mode
the collective pitch of the rotor blades, and hence rotor lift,
was reduced with up to about half the weight taken by the wings,
allowing much higher speeds than conventional. When approaching
to land the tips were relit, converting the aircraft back to helicopter
mode for a normal helicopter hover and landing.
1958 the Rotodyne prototype achieved economic cruise speeds of 150
knots. A world record speed of 190.9 mph was set on January 5, 1959
for the 100 km closed circuit. The craft had the remarkable safety
feature of being able to convert from autogiro mode to helicopter
mode and hover with one engine shut down and its prop feathered.
Additionally, it demonstrated safe landings in full autogiro mode.
greatest criticism of the Rotodyne, in spite of its performance
as a VTOL craft, was of the noise generated
by the tip jets. The noise attenuation program at the time of cancellation
had produced reductions down to the then-desired 96 db. at 600 ft.
distance. Noise critics failed to appreciate that the full power
tips-lit time in service was only about one minute during takeoff
and climb and one minute at landing. In fact, to prove a point,
test pilot Ron Gelattly made two flights over downtown London and
several takeoffs and landings at Battersea Heliport on a dead calm
morning with no complaints raised. At the time of the project's
cancellation the continuing development of silencers had further
reduced the noise level by another 16 db. Instrument flying the
aircraft was very stable and Gelattly often demonstrated transitions
from helicopter to autogiro and back again, in IMC, at less than
500 ft. above the ground!
Rotodyne's tip drive and unloaded rotor made a tremendous breakthrough
in performance and handling compared to pure helicopters and other
forms of convert-a-planes. The aircraft was flown at 175 knots and
pulled into a steep climbing high G turn with no adverse handling
characteristics. It was demonstrated at the Farnbourgh and Paris
Air Shows each year from 1958 to 1962 and always amazed onlookers.
From any point of view the Rotodyne was an aircraft ahead of its
Europe and Britain, city-center-to-city-center transport was being
touted as taking very little flying time. Kaman Helicopters in the
U. S. was proposing a licensesure for civil and military production.
Interest was shown from Okanagan Helicopters Ltd. of Vancouver,
B.C., New York Airways, Chicago Helicopter Airways and Japan Airlines,
who considered the aircraft for its Osaka-Tokyo route.
Nearly 1000 passengers, including a fair portion of the world's
airline chiefs, service chiefs and British Ministers of Parliament,
were flown as a demonstration of the enhanced safety of the prototype
in order to emphasize faith in the design.
January of 1959 British European Airways announced that it would
write a letter of intent for 6 developed Rotodynes, with the hope
of a requirement for up to 20 aircraft for operation on shorter
routes. This was in addition to an RAF "order" for 12
military transport version. In March of 1959 New York Airways planned
to purchase 5 Rotodynes costing about ten million dollars, with
an option for an additional 15 at a later date. The U.S. Army showed
considerable interest with a rumored buy of 200 machines. None of
then, was the project cancelled and the concept not pursued? Why
has there not been a logical progression of existing technology
dating back 40 years instead of a radical departure from that technology?
1959 the British Government, determined to reduce its participation
in the aviation industry, reduced the number of helicopter firms.
Under the direction of Minister of Aviation Duncan Sandys, the consolidation
process was begun. It was done by cutting government funding. Sandys
wanted one consolidated helicopter manufacturer centered on Westland
aircraft. This meant that Fairey, the helicopter division of Bristol,
would have to be taken over by the Westland firm.
February, 1962, the final axe fell, first with withdrawal by BEA,
then the withdrawal of the military order. The world's first vertical
takeoff military/civil transport died.
of this occured almost 40 years ago. Had the Rotodyne persevered,
accentuated with modern low fuel consumption engines and modern
electronics for the hydraulic control system, commerical aviation
would now have a transport of great potential competing with both
fixed and rotary wing machines.
would think such a remarkable aircraft would be retired to a prestigous
position in an elite British museum. In fact, the aircraft was dismantled
and destroyed, and all tooling which was used to create the Rotodyne
was destroyed. Even in a search of London's aviation museums and
memorabilia, there is no evidence other than the few articles which
were written in European and British aviation publications concerning
the craft. A few components have been found and brought together
at the International Helicopter Museum at Weston-Super-Mare.
problems with air transport are much the same as they were 40 years
ago, more intense. An interesting comment was made in 1989 by Mr.
Michael Heatly, author of the Illustrated History of Helicopters,
referring to the Rotodyne, "in many ways the Rotodyne was a
project decades ahead of its time. Many subsequent projects from
the drawing boards of the worlds' rotocraft manufacturers bore no
little relation to this futuristic craft that would seem more at
home in the 80's skys than those of the 50's. The possibility of
a similarly configured VTOL feeder liner achieving success in future
decades cannot be ruled out."
We invite you to view a Rotodyne promotional video.