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For the company, see Gyrodyne Company of America.
A
Gyrodyne is a heavier-than-air
aircraft with a rotor system that is normally driven by its engine for takeoff, hovering and landing like a helicopter, but which also has an additional propulsion system that is independent of the rotor system. At higher speeds, the rotor system acts similarly to that of an
autogyro, no longer driving the aircraft but simply providing lift.McKenna, James T. "One Step Beyond",
Rotor & Wing, February, 2007, page 54
In recent years a related concept, a gyrodyne with wings, has been promoted under the name
Heliplane; a term which was originally used by
Don Farrington to market the
Air & Space 18A gyroplane. There is controversy over the correct usage of the terms
gyrodyne and
heliplane. The terms
compound helicopter or
compound gyroplane are also used for such aircraft, although these definitions are not used consistently. The term
gyrodyne is an official aircraft class within the rotorcraft category in US FAR Part 1: Definitions and Abbreviations;
heliplane is an advertising term.
History
Gyrodyne concept
Once the initial challenges of rotary-wing flight had been solved with the development of
Cierva's Autogiro, research began to focus on improving their range of abilities. Jump take-off gave autogyros limited VTOL capability, and work then addressed the possibilities of true VTOL and hovering.
In Russia and Germany, engineers such
Anton Flettner moved the autogyro's propellor to stub wings to provide the anti-torque control that allowed the rotor to be driven by the aircraft's engine in flight. In forward flight, the aircraft would fly as an autogyro or helicopter. One such aircraft was the Flettner Fl 184.
Early autogyros had stub wings which provided part of the lift in forward flight, but the main source of lift was the rotor. The primary purpose of the wings in these early autogiros was to provide efficient support for the flight control surfaces since cyclic control of the rotor had not yet been developed. Some attempts were made to stop the rotor and use it as a fixed wing, such as the Herrick Vertaplane, but cumbersome mechanisms and rotor instability during inflight conversions posed insurmountable problems at the then-current level of technology.
In Britain, Prof. J.A.J.Bennett (Chief Engineer of the Cierva Autogiro Company, Ltd.) developed a third distinct type of rotorcraft termed
gyrodyne. This rotorcraft was described in US Patent 2,317,340 granted to the Autogiro Company of America (formed by Harold F. Pitcairn to license Autogiro patents in the United States) in 1943 as:
In other words, in helicopters airflow through the rotor is downwards; in autogyros airflow through the rotor is upwards; in gyrodynes airflow through the rotor is minimal.
Bennett's gyrodyne had a shaft-driven rotor with torque correction and propulsion for translational flight provided by a side-mounted propeller. Collective pitch of the rotor was a function of, and increased automatically with, shaft torque. During hover and low-speed flight, collective pitch of the propeller was controlled by the pilot with the yaw pedals. As airspeed increased, propeller drag also increased and in order to maintain constant rpm it drew increased power from the engine, which in turn reduced torque at the rotor hub. The latter condition caused an automatic reduction in rotor collective pitch. At cruise airspeed, the rotor operated at autorotative pitch with the tip-path plane parallel to the direction of flight; all propulsion was provided by the propeller. As airspeed was reduced, propeller torque demand decreased which resulted in increased torque at the rotor hub which in turn caused an increase in collective pitch.
Before ca. 1970, the term
Gyrodyne exclusively used Bennett's definition. In the helicopter engineering text
Aerodynamics of the Helicopter, by Gessow and Myers (1952) we find :
US Patent 2,317,340 includes provision for a gyrodyne to operate as an autogyro inflight, the aircraft converting from from gyrodyne — not helicopter — to autogyro and back inflight.
Later development
In later times, Bennett's term
gyrodyne was reinterpreted to mean
compound gyroplane. This kind of aircraft operates as a
helicopter in hover and low-speed flight, and as an
autogyro in cruise flight. It does not need a tail rotor, otherwise required in a helicopter to provide a torque to counter the rotating effect of the engine that powers the main rotor, as in models such as the Fairey Aviation
Fairey FB-1 Gyrodyne the counter-torque was provided from the propellor(s) driving the craft forward. In the subsequent
Fairey Jet Gyrodyne the rotor was powered by jets at the rotor tips during vertical take-off; the jets coming from compressors powered by the engine rather than directly coupled there was no counter-torque required at all.
Helicopter development became practical after the fundamental engineering and practice of the rotary-wing reached an advanced level with the Autogiro. Much of the work in this area was due to the Cierva Autogiro Company, Ltd. (UK) and its partner Autogiro Company of America (US), which undertook pioneering development in rotary-wing theory such as
rotor dynamics, Cyclic pitch control and Collective pitch control. Unlicensed use of Autogiro technology by the US Government resulted in a suit by Harold Pitcairn in 1951 that was settled in 1978 in his favor with the then largest ever award for damages in the United States.
The first Fairey Gyrodyne crashed during a high speed test due to hub failure caused by poor machining of a flapping link. The second Gyrodyne, renamed
Jet Gyrodyne, was used to develop a pressure-jet rotor drive system with air supplied from the piston-engine powered compressor. At the tip of each stub wing were rearward-facing propellers which provided both yaw control and propulsion in forward flight. Pressure-jet development was led by A.G. Forsyth and August Stepan, the latter working on the Second World War era WN-342 rotor drive system. Though retaining the name
Gyrodyne, the Jet Gyrodyne was in fact a compound autogyro. This led to the prototype
Fairey Rotodyne which was developed to combine the efficiency of an aeroplane at cruise with the VTOL capability of a helicopter; it would have served as a short haul airliner from city centres to airports. It had short wings that carried the turboprop horizontal flight engines and up to 30% of the aircraft's weight in forward flight. The rotor was driven by tip-mounted jets at take off and landing. Fairey's development efforts were initially led by Bennett, followed by his successor George S. Hislop. Though the Cierva Autogiro Company, Ltd., by then a helicopter company, had been absorbed into Saunders Roe in the early 1950s, later itself acquired by
Westland Helicopters, many of its most experienced Autogiro engineers joined Bennett at Fairey where they worked on the Gyrodyne and Rotodyne.
Despite considerable commercial and military interest worldwide in the prototype Type Y Rotodyne for air transport, Fairey decided to develop a larger and more powerful Type Z Rotodyne which, together with withdrawal of British Government support in 1962, resulted in the termination of the project.
An aircraft called a "
Heliplane" was built by Kayaba in 1954. It was essentially a
Cessna 170 with wings reduced to stubs sufficient to carry the undercarriage and a rotor powered by tip ram-jets.
The McDonnell XV-1, also of the 1950s, was an autogyro with tip jets to give vertical take off. In this case the intention was to create a military aircraft with helicopter VTOL but capable of higher speeds. Two prototypes were built and tested, the first being the first rotary-wing aircraft to make an airborne transition from powered rotor flight to unpowered rotor flight; the second XV-1 became the world's first rotorcraft to exceed 200 mph in level flight on 10 October 1956. The XV-1 project was terminated in 1957.
Modern developments
The term "Gyrodyne" is no longer used with Bennett's original meaning. The
Federal Aviation Administration (FAA) gives the modern legal definition of a Gyrodyne in the USA as a rotor wing aircraft that powers its rotor for takeoff and landing, but en route, flies in autorotation, like a gyroplane, without power to the rotor. Forward thrust is provided by engine driven propellers. Being able to fly in autorotation gives the gyrodyne all of the advantages and simplicity of a gyroplane. Thus, the modern definition of "
Gyrodyne" actually describes the wider idea of a "
compound gyroplane". To add to this confusion, the Gyrodyne Company of America has also produced a number of coaxial
helicopters under the US trademark "
Gyrodyne".
FAA Rulemaking Petition number FAA-2006-24170-1 was filed on
10 March 2006 to redefine gyrodyne to its accepted historical and engineering definition, and also to add the terms
compound helicopter and
compound gyroplane to
FAR Part 1: Definitions and Abbrevations.
As with
Gyrodyne, the term
Heliplane has been redefined from its original use as an advertising term, and given a wider meaning. DARPA is funding a project under the "Heliplane" name to extend the gyrodyne concept. The new aircraft will use a rotor for take-off and landing vertically, and hovering, together with sustantial wings to provide most of the required lift at cruise. These are hoped to combine the large cargo capacity, fuel efficiency, and high cruise speed of an aeroplane with the VTOL and hovering capabilities of a gyrodyne. Rotor & Wing magazine February 2007 reports that the project is "..a multi-year $40-million, four-phase program. Groen Brothers is working on phase one of that program, a 15-month effort...(it) combines the "gyroplane" ..with a fixed-wing business jet. The team is using the A700, in the very-light-jet class, which was developed by Adam Aircraft Industries."
Since
2005, several companies have begun research programs directed at developing a heliplane concept.
Groen Brothers Aviation have concentrated their efforts on developing techniques for converting proven aeroplane designs into gyrodynes; the conversion intended to be a cheaper route than developing aircraft from scratch. Their concept designs have added rotors, trimmed wings (though they are still major structures) and modified tailplanes.
CarterCopter have focused on developing technologies with the intention of selling and licensing intellectual property rights developed. Their patents include a high-inertia rotor that allows the aircraft to hover for a short time
while unpowered; and the concept of slowing - but not stopping - the rotor at cruise speeds. The rotor is combined with wings that are optimised for high-speed flight only, providing a low-drag configuration.
Trademark
Gyrodyne as a US
trademark was granted to Gyrodyne Company Of America, Inc. in 1950.
The term gyrodyne was defined by a US Patent 2,317,340, issued in 1943 itself based on a 1939 UK Patent assigned to the
Cierva Autogiro Company, Ltd., in which
gyrodyne is "a rotary wing aircraft intermediate in type, hereinafter referred to as
gyrodyne, between a rotaplane (with the rotor free for autorotation and an upward total axial flow through the rotor disc), on the one hand, and a pure helicopter (with the rotor driven, and a downward total axial flow through the rotor disc), on the other hand, that is with a mean axial flow through the rotor disc substantially zero at high forward speed".
The
gyrodyne, invented by
Cierva Autogiro Company engineer James Allan Jamieson Bennett, is a third distinct type of rotorcraft, the category of aircraft that includes the gyroplane and helicopter. A gyrodyne has a shaft-driven rotor with torque correction and propulsion for translational flight provided by a side-mounted propeller. Collective pitch of the rotor is a function of, and increases automatically with, shaft torque. During hover and low-speed flight, collective pitch of the propeller is controlled by the pilot with the yaw pedals. As airspeed increases, propeller drag also increases and in order to maintain constant rpm it draws increased power from the engine, which in turn reduces torque at the rotor hub. The latter condition causes an automatic reduction in rotor collective pitch. At cruise airspeed, the rotor operates at autorotative pitch with the tip-path plane parallel to the direction of flight; all propulsion is provided by the propeller. As airspeed is reduced, propeller torque demand decreases which results in increased torque at the rotor hub which in turn causes an increase in collective pitch.
Other features included in the definition of
gyrodyne include:1. Low rotor disc loading.2. Ease of piloting.3. Compact fuselage.4. Use of a powered rotor which operates in autorotative pitch in cruise flight.
The USA Federal Aviation Administration (FAA) in
Federal Aviation Regulations, Part 1: Definitions and Abbreviations, defines a gyrodyne as a rotary-wing
aircraft that powers its rotor for takeoff, landing and low speed flight, and in cruise flight flies with the rotor in autorotation. Forward thrust is provided by one or more engine driven propeller. This definition of gyrodyne is incorrect; it instead defines a "compound gyroplane."
Heliplanes
The term
heliplane was proposed by Don Farrington as an alternative to
Autogyro in an attempt to market the
Air and Space 18A gyroplane. An application for a U.S.
trademark by the Air & Space America Corporation was abandoned in 1994. This term has been adopted as an alternate term for
compound gyroplane, often incorrectly defined as
gyrodyne in which by definition the rotor is always powered in flight.
The Fairey Gyrodyne is the only example of a gyrodyne to have been constructed. The second prototype gyrodyne was converted to a
compound gyroplane to develop the tip-jet rotor drive system employed on the Fairey Rotodyne "compound gyroplane."
Examples
Examples
- Flettner (Germany)
- The Flettner Fl 184 (1935) helicopter/autogyro
- Flettner 185 (1938) "Avia" Helicopter Developments
- Focke-Wulf
- Focke-Wulf Fw Triebflugel - a WW2 German design that used a jet powered rotor in place of wings.
- Fairey Aviation (United Kingdom)
- Fairey Gyrodyne
- Fairey Jet Gyrodyne
- Fairey Rotodyne (1957)
References
- U.S. Patent 2,317,340: Helicopter. J.A.J.Bennett. 27 April 1943
- "The Fairey Gyrodyne." J.A.J. Bennett. Journal of the Royal Aeronautical Society, 1949, Vol. 53
- "Aerodynamics of the Helicopter". Alfred Gessow & Garry C. Myers, Jr. Frederick Ungar Publishing Company, NY. 1952, republished 1962.
- "Principles of Helicopter Aerodynamics". J. Gordon Leishman, Cambridge University Presss, N.Y. 2000, reprinted 2005.
- "Principles of Helicopter Engineering". Jacob Shapiro, Temple Press Ltd., London, 1955.
- " Development of the Autogiro : A Technical Perspective" : J. Gordon Leishman: Hofstra University, New York, 2003.
- From Autogiro to Gyroplane : The Amazing Survival of an Aviation Technology: Bruce H. Charnov, 2003.
- Autogyro
- U.S. Patent 2,317,340: "Helicopter" by J.A.J. Bennett, 27 April 1943
External links
- VSTOL.org Wheel of Misfortune
- The Fairey Rotodyne: An Idea Whose Time Has Come – Again?
- Gyrodyne and Heliplane concepts (2005)
- Heliplane concept
- Jet Gyrodyne (1954)
See also
For the company, see Gyrodyne Company of America.
A
Gyrodyne is a heavier-than-air aircraft with a rotor system that is normally driven by its engine for takeoff, hovering and landing like a helicopter, but which also has an additional propulsion system that is independent of the rotor system. At higher speeds, the rotor system acts similarly to that of an
autogyro, no longer driving the aircraft but simply providing lift.McKenna, James T. "One Step Beyond",
Rotor & Wing, February, 2007, page 54
In recent years a related concept, a gyrodyne with wings, has been promoted under the name
Heliplane; a term which was originally used by Don Farrington to market the Air & Space 18A gyroplane. There is controversy over the correct usage of the terms
gyrodyne and
heliplane. The terms
compound helicopter or
compound gyroplane are also used for such aircraft, although these definitions are not used consistently. The term
gyrodyne is an official aircraft class within the rotorcraft category in US FAR Part 1: Definitions and Abbreviations;
heliplane is an advertising term.
History
Gyrodyne concept
Once the initial challenges of rotary-wing flight had been solved with the development of Cierva's Autogiro, research began to focus on improving their range of abilities. Jump take-off gave autogyros limited VTOL capability, and work then addressed the possibilities of true VTOL and hovering.
In Russia and Germany, engineers such Anton Flettner moved the autogyro's propellor to stub wings to provide the anti-torque control that allowed the rotor to be driven by the aircraft's engine in flight. In forward flight, the aircraft would fly as an autogyro or helicopter. One such aircraft was the
Flettner Fl 184.
Early autogyros had stub wings which provided part of the lift in forward flight, but the main source of lift was the rotor. The primary purpose of the wings in these early autogiros was to provide efficient support for the flight control surfaces since cyclic control of the rotor had not yet been developed. Some attempts were made to stop the rotor and use it as a fixed wing, such as the
Herrick Vertaplane, but cumbersome mechanisms and rotor instability during inflight conversions posed insurmountable problems at the then-current level of technology.
In Britain, Prof.
J.A.J.Bennett (Chief Engineer of the Cierva Autogiro Company, Ltd.) developed a third distinct type of rotorcraft termed
gyrodyne. This rotorcraft was described in US Patent 2,317,340 granted to the Autogiro Company of America (formed by Harold F. Pitcairn to license Autogiro patents in the United States) in 1943 as:
In other words, in helicopters airflow through the rotor is downwards; in autogyros airflow through the rotor is upwards; in gyrodynes airflow through the rotor is minimal.
Bennett's gyrodyne had a shaft-driven rotor with torque correction and propulsion for translational flight provided by a side-mounted propeller. Collective pitch of the rotor was a function of, and increased automatically with, shaft torque. During hover and low-speed flight, collective pitch of the propeller was controlled by the pilot with the yaw pedals. As airspeed increased, propeller drag also increased and in order to maintain constant rpm it drew increased power from the engine, which in turn reduced torque at the rotor hub. The latter condition caused an automatic reduction in rotor collective pitch. At cruise airspeed, the rotor operated at autorotative pitch with the tip-path plane parallel to the direction of flight; all propulsion was provided by the propeller. As airspeed was reduced, propeller torque demand decreased which resulted in increased torque at the rotor hub which in turn caused an increase in collective pitch.
Before ca. 1970, the term
Gyrodyne exclusively used Bennett's definition. In the helicopter engineering text
Aerodynamics of the Helicopter, by Gessow and Myers (1952) we find :
US Patent 2,317,340 includes provision for a gyrodyne to operate as an autogyro inflight, the aircraft converting from from gyrodyne — not helicopter — to autogyro and back inflight.
Later development
In later times, Bennett's term
gyrodyne was reinterpreted to mean
compound gyroplane. This kind of aircraft operates as a
helicopter in hover and low-speed flight, and as an autogyro in cruise flight. It does not need a tail rotor, otherwise required in a helicopter to provide a torque to counter the rotating effect of the engine that powers the main rotor, as in models such as the
Fairey Aviation Fairey FB-1 Gyrodyne the counter-torque was provided from the propellor(s) driving the craft forward. In the subsequent
Fairey Jet Gyrodyne the rotor was powered by jets at the rotor tips during vertical take-off; the jets coming from compressors powered by the engine rather than directly coupled there was no counter-torque required at all.
Helicopter development became practical after the fundamental engineering and practice of the rotary-wing reached an advanced level with the Autogiro. Much of the work in this area was due to the Cierva Autogiro Company, Ltd. (UK) and its partner Autogiro Company of America (US), which undertook pioneering development in rotary-wing theory such as
rotor dynamics, Cyclic pitch control and Collective pitch control. Unlicensed use of Autogiro technology by the US Government resulted in a suit by Harold Pitcairn in 1951 that was settled in 1978 in his favor with the then largest ever award for damages in the United States.
The first Fairey Gyrodyne crashed during a high speed test due to hub failure caused by poor machining of a flapping link. The second Gyrodyne, renamed
Jet Gyrodyne, was used to develop a pressure-jet rotor drive system with air supplied from the piston-engine powered compressor. At the tip of each stub wing were rearward-facing propellers which provided both yaw control and propulsion in forward flight. Pressure-jet development was led by A.G. Forsyth and August Stepan, the latter working on the Second World War era WN-342 rotor drive system. Though retaining the name
Gyrodyne, the Jet Gyrodyne was in fact a compound autogyro. This led to the prototype
Fairey Rotodyne which was developed to combine the efficiency of an aeroplane at cruise with the VTOL capability of a helicopter; it would have served as a short haul airliner from city centres to airports. It had short wings that carried the turboprop horizontal flight engines and up to 30% of the aircraft's weight in forward flight. The rotor was driven by tip-mounted jets at take off and landing. Fairey's development efforts were initially led by Bennett, followed by his successor George S. Hislop. Though the Cierva Autogiro Company, Ltd., by then a helicopter company, had been absorbed into Saunders Roe in the early 1950s, later itself acquired by Westland Helicopters, many of its most experienced Autogiro engineers joined Bennett at Fairey where they worked on the Gyrodyne and Rotodyne.
Despite considerable commercial and military interest worldwide in the prototype Type Y Rotodyne for air transport, Fairey decided to develop a larger and more powerful Type Z Rotodyne which, together with withdrawal of British Government support in 1962, resulted in the termination of the project.
An aircraft called a "
Heliplane" was built by
Kayaba in 1954. It was essentially a
Cessna 170 with wings reduced to stubs sufficient to carry the undercarriage and a rotor powered by tip ram-jets.
The
McDonnell XV-1, also of the 1950s, was an autogyro with tip jets to give vertical take off. In this case the intention was to create a military aircraft with helicopter VTOL but capable of higher speeds. Two prototypes were built and tested, the first being the first rotary-wing aircraft to make an airborne transition from powered rotor flight to unpowered rotor flight; the second XV-1 became the world's first rotorcraft to exceed 200 mph in level flight on 10 October 1956. The XV-1 project was terminated in 1957.
Modern developments
The term "Gyrodyne" is no longer used with Bennett's original meaning. The
Federal Aviation Administration (FAA) gives the modern legal definition of a Gyrodyne in the USA as a rotor wing aircraft that powers its rotor for takeoff and landing, but en route, flies in autorotation, like a gyroplane, without power to the rotor. Forward thrust is provided by engine driven propellers. Being able to fly in autorotation gives the gyrodyne all of the advantages and simplicity of a gyroplane. Thus, the modern definition of "
Gyrodyne" actually describes the wider idea of a "
compound gyroplane". To add to this confusion, the Gyrodyne Company of America has also produced a number of coaxial helicopters under the US trademark "
Gyrodyne".
FAA Rulemaking Petition number FAA-2006-24170-1 was filed on 10 March 2006 to redefine gyrodyne to its accepted historical and engineering definition, and also to add the terms
compound helicopter and
compound gyroplane to
FAR Part 1: Definitions and Abbrevations.
As with
Gyrodyne, the term
Heliplane has been redefined from its original use as an advertising term, and given a wider meaning. DARPA is funding a project under the "Heliplane" name to extend the gyrodyne concept. The new aircraft will use a rotor for take-off and landing vertically, and hovering, together with sustantial wings to provide most of the required lift at cruise. These are hoped to combine the large cargo capacity, fuel efficiency, and high cruise speed of an aeroplane with the VTOL and hovering capabilities of a gyrodyne. Rotor & Wing magazine February 2007 reports that the project is "..a multi-year $40-million, four-phase program. Groen Brothers is working on phase one of that program, a 15-month effort...(it) combines the "gyroplane" ..with a fixed-wing business jet. The team is using the A700, in the very-light-jet class, which was developed by Adam Aircraft Industries."
Since 2005, several companies have begun research programs directed at developing a heliplane concept.
Groen Brothers Aviation have concentrated their efforts on developing techniques for converting proven aeroplane designs into gyrodynes; the conversion intended to be a cheaper route than developing aircraft from scratch. Their concept designs have added rotors, trimmed wings (though they are still major structures) and modified tailplanes.
CarterCopter have focused on developing technologies with the intention of selling and licensing intellectual property rights developed. Their patents include a high-inertia rotor that allows the aircraft to hover for a short time
while unpowered; and the concept of slowing - but not stopping - the rotor at cruise speeds. The rotor is combined with wings that are optimised for high-speed flight only, providing a low-drag configuration.
Trademark
Gyrodyne as a US trademark was granted to Gyrodyne Company Of America, Inc. in 1950.
The term gyrodyne was defined by a US Patent 2,317,340, issued in 1943 itself based on a 1939 UK Patent assigned to the
Cierva Autogiro Company, Ltd., in which
gyrodyne is "a rotary wing aircraft intermediate in type, hereinafter referred to as
gyrodyne, between a rotaplane (with the rotor free for autorotation and an upward total axial flow through the rotor disc), on the one hand, and a pure helicopter (with the rotor driven, and a downward total axial flow through the rotor disc), on the other hand, that is with a mean axial flow through the rotor disc substantially zero at high forward speed".
The
gyrodyne, invented by
Cierva Autogiro Company engineer James Allan Jamieson Bennett, is a third distinct type of
rotorcraft, the category of aircraft that includes the
gyroplane and helicopter. A gyrodyne has a shaft-driven rotor with torque correction and propulsion for translational flight provided by a side-mounted propeller. Collective pitch of the rotor is a function of, and increases automatically with, shaft torque. During hover and low-speed flight, collective pitch of the propeller is controlled by the pilot with the yaw pedals. As airspeed increases, propeller drag also increases and in order to maintain constant rpm it draws increased power from the engine, which in turn reduces torque at the rotor hub. The latter condition causes an automatic reduction in rotor collective pitch. At cruise airspeed, the rotor operates at autorotative pitch with the tip-path plane parallel to the direction of flight; all propulsion is provided by the propeller. As airspeed is reduced, propeller torque demand decreases which results in increased torque at the rotor hub which in turn causes an increase in collective pitch.
Other features included in the definition of
gyrodyne include:1. Low rotor disc loading.2. Ease of piloting.3. Compact fuselage.4. Use of a powered rotor which operates in autorotative pitch in cruise flight.
The USA
Federal Aviation Administration (FAA) in
Federal Aviation Regulations, Part 1: Definitions and Abbreviations, defines a gyrodyne as a rotary-wing
aircraft that powers its rotor for takeoff, landing and low speed flight, and in cruise flight flies with the rotor in autorotation. Forward thrust is provided by one or more engine driven propeller. This definition of gyrodyne is incorrect; it instead defines a "compound gyroplane."
Heliplanes
The term
heliplane was proposed by
Don Farrington as an alternative to
Autogyro in an attempt to market the
Air and Space 18A gyroplane. An application for a U.S.
trademark by the Air & Space America Corporation was abandoned in 1994. This term has been adopted as an alternate term for
compound gyroplane, often incorrectly defined as
gyrodyne in which by definition the rotor is always powered in flight.
The
Fairey Gyrodyne is the only example of a gyrodyne to have been constructed. The second prototype gyrodyne was converted to a
compound gyroplane to develop the tip-jet rotor drive system employed on the Fairey Rotodyne "compound gyroplane."
Examples
- Fairey Aviation (United Kingdom)
- Fairey Gyrodyne
Examples
- Flettner (Germany)
- The Flettner Fl 184 (1935) helicopter/autogyro
- Flettner 185 (1938) "Avia" Helicopter Developments
- Fairey Aviation (United Kingdom)
- Fairey Gyrodyne
- Fairey Jet Gyrodyne
- Fairey Rotodyne (1957)
References
- U.S. Patent 2,317,340: Helicopter. J.A.J.Bennett. 27 April 1943
- "The Fairey Gyrodyne." J.A.J. Bennett. Journal of the Royal Aeronautical Society, 1949, Vol. 53
- "Aerodynamics of the Helicopter". Alfred Gessow & Garry C. Myers, Jr. Frederick Ungar Publishing Company, NY. 1952, republished 1962.
- "Principles of Helicopter Aerodynamics". J. Gordon Leishman, Cambridge University Presss, N.Y. 2000, reprinted 2005.
- "Principles of Helicopter Engineering". Jacob Shapiro, Temple Press Ltd., London, 1955.
- " Development of the Autogiro : A Technical Perspective" : J. Gordon Leishman: Hofstra University, New York, 2003.
- From Autogiro to Gyroplane : The Amazing Survival of an Aviation Technology: Bruce H. Charnov, 2003.
- Autogyro
- U.S. Patent 2,317,340: "Helicopter" by J.A.J. Bennett, 27 April 1943
External links
- VSTOL.org Wheel of Misfortune
- The Fairey Rotodyne: An Idea Whose Time Has Come – Again?
- Gyrodyne and Heliplane concepts (2005)
- Heliplane concept
- Jet Gyrodyne (1954)
See also
- tilt-rotor - another approach to rotor based VTOL.
- Gyrodyne Company of America (USA) - producers of helicopters under the brand name "Gyrodyne"