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Coordinates	39°44′21″N104°59′5″N
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An autogyro (from Spanish ''autogiro''), also known as gyroplane, gyrocopter, or rotaplane, is a type of rotorcraft which uses an unpowered rotor in autorotation to develop lift, and an engine-powered propeller, similar to that of a fixed-wing aircraft, to provide thrust. While similar to a helicopter rotor in appearance, the autogyro's rotor must have air flowing through the rotor disc in order to generate rotation. Invented by the Spanish engineer Juan de la Cierva to create an aircraft that could safely fly at slow speeds, the autogyro was first flown on 9 January 1923, at Cuatro Vientos Airfield in Madrid. De la Cierva's aircraft resembled the fixed-wing aircraft of the day, with a front-mounted engine and propeller in a tractor configuration to pull the aircraft through the air. Late-model autogyros patterned after Dr. Igor Bensen's designs feature a rear-mounted engine and propeller in a pusher configuration. The term ''Autogiro'' was a trademark of the Cierva Autogiro Company, and the term ''Gyrocopter'' was used by E. Burke Wilford who developed the Reiseler Kreiser feathering rotor equipped gyroplane in the first half of the twentieth century. The latter term was later adopted as a trademark by Bensen Aircraft.

Configuration

An autogyro is characterized by a free-spinning rotor that turns because of passage of air upward through the rotor. The vertical component of the total aerodynamic reaction of the rotor gives lift for the vehicle, and sustains the autogyro in the air. A separate propeller provides forward thrust, and can be placed in a tractor configuration with the engine and propeller at the front of the fuselage (e.g., Cierva), or pusher configuration with the engine and propeller at the rear of the fuselage (e.g., Bensen).

Whereas a helicopter works by forcing the rotor blades through the air, pushing air downwards, the autogyro rotor blade generates lift in the same way as a glider's wing by changing the angle of the air as it moves upwards and backwards relative to the rotor blade. The free-spinning blades turn by autorotation; the rotor blades are angled so that they not only give lift, but the angle of the blades causes the lift to accelerate the blades' rotation rate, until the rotor turns at a stable speed with the drag and thrust forces in balance.

Pitch control of the autogyro is by tilting the rotor fore and aft; roll control is by tilting the rotor laterally (side to side). Three designs to affect the tilt of the rotor are a tilting hub (Cierva), swashplate (Air & Space 18A), or servo-flaps (Kaman SAVER). A rudder provides yaw control. On pusher configuration autogyros, the rudder is typically placed in the propeller slipstream to maximize yaw control at low airspeed (but not always, as seen in the McCulloch J-2, with twin rudders placed outboard of the propeller arc).

Flight controls

There are three primary flight controls: control stick, rudder pedals, and throttle. The control stick is termed ''cyclic'' and tilts the rotor in the desired direction to provide pitch and roll control. The rudder pedals provide yaw control, and the throttle controls engine power.

Secondary flight controls include the rotor transmission clutch, also known as a pre-rotator, which when engaged drives the rotor to start it spinning before takeoff, and collective pitch to reduce blade pitch before driving the rotor. Collective pitch controls are not usually fitted to autogyros, but can be found on the Air & Space 18A and McCulloch J-2 and the Westermayr Tragschrauber and are capable of near VTOL performance. Unlike a helicopter, autogyros without collective pitch need a runway to takeoff; however they are capable of landing with a very short or zero ground roll.

Pusher vs tractor configuration

Modern autogyros typically follow one of two basic configurations. The most common design is the pusher configuration, where the engine and propeller are located behind the pilot and rotor mast, such as in the Bensen "Gyrocopter". It was developed by Igor Bensen in the decades following World War II, and came into widespread use shortly afterward.

Less common today is the tractor configuration. In this version the engine and propeller are located at the front of the aircraft, ahead of the pilot and rotor mast. This was the primary configuration in early autogyros, but became less common after the advent of the helicopter. It has enjoyed a revival since the mid 1970s.

History

Juan de la Cierva was a Spanish engineer and aeronautical enthusiast. In 1921, he participated in a design competition to develop a bomber for the Spanish military. De la Cierva designed a three-engined aircraft, but during an early test flight, the bomber stalled and crashed. De la Cierva was troubled by the stall phenomenon and vowed to develop an aircraft that could fly safely at low airspeeds. The result was the first successful rotorcraft, which he named ''Autogiro'' in 1923. De la Cierva's autogyro used an airplane fuselage with a forward-mounted propeller and engine, a rotor mounted on a mast, and a horizontal and vertical stabilizer.

Early development

De la Cierva's first three designs (C.1, C.2, and C.3) were unstable because of aerodynamic and structural deficiencies in their rotors. His fourth design, the C.4, made the first successful flight of an autogyro on 9 January 1923, piloted by Alejandro Gomez Spencer at Cuatro Vientos airfield in Madrid, Spain. De la Cierva had fitted the rotor of the C.4 with flapping hinges to attach each rotor blade to the hub. The flapping hinges allowed each rotor blade to flap, or move up and down, to compensate for dissymmetry of lift, the difference in lift produced between the right and left sides of the rotor as the autogyro moves forward. Three days later, the engine failed shortly after takeoff and the aircraft descended slowly and steeply to a safe landing, validating De la Cierva's efforts to produce an aircraft that could be flown safely at low airspeeds.

De la Cierva developed his C.6 model with the assistance of Spain's Military Aviation establishment, having expended all his funds on development and construction of the first five prototypes. The C.6 first flew in February 1925, including a flight of 10.5 km (7 miles) from Cuatro Vientos airfield to Getafe airfield in about 8 minutes, a significant accomplishment for any rotorcraft of the time. Shortly after De la Cierva's success with the C.6, Cierva accepted an offer from Scottish industrialist James G. Weir to establish the Cierva Autogiro Company in England, following a demonstration of the C.6 before the British Air Ministry at RAE Farnborough, on 20 October 1925. Britain had become the world centre of autogyro development.

A crash in February 1927, caused by blade root failure, led to an improvement in rotor hub design. A drag hinge was added in conjunction with the flapping hinge to allow each blade to move fore and aft and relieve in-plane stresses, generated as a byproduct of the flapping motion. This development led to the Cierva C.8, which, on 18 September 1928, made the first rotorcraft crossing of the English Channel followed by a tour of Europe.

The U.S. industrialist Harold Frederick Pitcairn, upon learning of the successful flights of the autogyro, had previously visited De la Cierva in Spain. In 1928 he visited him again, in England, after taking a C.8 L.IV test flight piloted by Arthur H.C.A. Rawson. Being particularly impressed with the autogyro's safe vertical descent capability, Pitcairn purchased a C.8 L.IV with a Wright Whirlwind engine. Arriving in the United States on 11 December 1928 accompanied by Rawson, this autogyro was redesignated C.8W. Subsequently, production of autogyros was licensed to a number of manufacturers, including the Pitcairn Autogiro Company in the U.S. and Focke-Wulf of Germany.

In 1927 Engelbert Zaschka, a pioneering German engineer, invented a combined helicopter and autogyro. The principal advantage of the Zaschka machine is in its ability to remain motionless in the air for any length of time and to descend in a vertical line, so that a landing may be accomplished on the flat roof of a large house. In appearance, the machine does not differ much from the ordinary monoplane, but the carrying wings revolve around the body.

Development of the autogyro continued in search for a means to accelerate the rotor prior to takeoff (called prerotating). Rotor drives initially took the form of a rope wrapped around the rotor axle and then pulled by a team of men to accelerate the rotor - this was followed by a long taxi to bring the rotor up to speed sufficient for takeoff. The next innovation was flaps on the tail to redirect the propeller slipstream into the rotor while on the ground. This design was first tested on a C.19 in 1929. Efforts in 1930 had shown that development of a light and efficient mechanical transmission was not a trivial undertaking. But in 1932, the Pitcairn-Cierva Autogiro Company of Willow Grove, Pennsylvania, United States, finally solved the problem with a transmission driven by the engine.

De la Cierva's early autogyros were fitted with fixed rotor hubs, small fixed wings, and control surfaces like those of a fixed-wing aircraft. At low airspeeds, the control surfaces became ineffective and could readily lead to loss of control, particularly during landing. In response, Cierva developed a direct control rotor hub, which could be tilted in any direction by the pilot. De la Cierva's direct control was first developed on the Cierva C.19 Mk. V and saw production on the Cierva C.30 series of 1934. In March 1934 this type of autogyro became the first rotorcraft to take off and land on the deck of a ship, when a C.30 performed trials on board the Spanish navy seaplane tender ''Dédalo'' off Valencia.

Later that year, during the leftist Asturias' revolt in October, an autogyro made a reconnaissance flight for the loyal troops, marking the first military employment of a rotorcraft.

When improvements in helicopters made them practical, autogyros became largely neglected. They were, however, used in the 1930s by major newspapers, and by the US Postal Service for mail service between the Camden, NJ airport (USA) and the top of the post office building in downtown Philadelphia, Pennsylvania (USA).

World War II

In World War II, Germany pioneered a very small gyroglider rotor kite, the Focke-Achgelis Fa 330 "Bachstelze" (Water-wagtail), towed by U-boats to provide aerial surveillance.

The Imperial Japanese Army developed the Kayaba Ka-1 Autogyro for reconnaissance, artillery-spotting, and anti-submarine uses. The Ka-1 was based on the Kellett KD-1 first imported to Japan in 1938. The craft was initially developed for use as an observation platform and for artillery spotting duties. The Army liked the craft's short take-off span, and especially its low maintenance requirements. In 1941 production began, with the machines assigned to artillery units for spotting the fall of shells. These carried two crewmen: a pilot and a spotter.

Later, the Japanese Army commissioned two small aircraft carriers intended for coastal antisubmarine (ASW) duties. The spotter's position on the Ka-1 was modified in order to carry one small depth charge. Ka-1 ASW autogyros operated from shore bases as well as the two small carriers. They appear to have been responsible for at least one submarine sinking.

The Avro Rota autogyro was used by the Royal Air Force to calibrate the coastal radar stations during and after the Battle of Britain.

Postwar developments

The autogyro was resurrected after World War II when Dr. Igor Bensen, a Russian immigrant, saw a captured German U-Boat's Fa 330 gyroglider and was fascinated by its characteristics. At work he was tasked with the analysis of the British military "Rotachute" gyro glider designed by expatriate Austrian Raoul Hafner. This led him to adapt the design for his own purposes and eventually market the B-7. Bensen submitted an improved version, the Bensen B-8M, for testing to the United States Air Force, which designated it the X-25. The B-8M was designed to use surplus McCulloch engines used on flying unmanned target drones.

Ken Wallis developed a miniature autogyro craft, the ''Wallis'' autogyro, in England in the 1960s, and autogyros built similar to Wallis' design appeared for a number of years. Ken Wallis' designs have been used in various scenarios including military training, police reconnaissance, and in another case a search for the Loch Ness Monster.

Three different autogyro designs have been certified by the Federal Aviation Administration for commercial production: the Umbaugh U-18/Air & Space 18A of 1965, the Avian 2-180 Gyroplane of 1967, and the McCulloch J-2 of 1972. All have been commercial failures, for various reasons.

Bensen Gyrocopter

The basic Bensen ''Gyrocopter'' design is a simple frame of square aluminium or galvanized steel tubing, reinforced with triangles of lighter tubing. It is arranged so that the stress falls on the tubes, or special fittings, not the bolts. A front-to-back keel mounts a steerable nosewheel, seat, engine, and a vertical stabilizer. Outlying mainwheels are mounted on an axle. Some versions may mount seaplane-style floats for water operations. Bensen-type autogyros use a pusher configuration for simplicity and to increase visibility for the pilot. Power can be supplied by a variety of engines. McCulloch drone engines, Rotax marine engines, Subaru automobile engines, and other designs have been used in Bensen-type designs.

The rotor is mounted atop the vertical mast. The rotor system of all Bensen-type autogyros is of a two-blade teetering design. There are some disadvantages associated with this rotor design, but the simplicity of the rotor design lends itself to ease of assembly and maintenance and is one of the reasons for its popularity. Aircraft-quality birch was specified in early Bensen designs, and a wood/steel composite is used in the world speed record holding Wallis design. Gyroplane rotor blades are made from other materials such as aluminium and GRP-based composite blades.

Because of Bensen's pioneering of the concept and the popularity of his design, "Gyrocopter" has become a genericized trademark for pusher configuration autogyros.

The success of Bensen triggered a number of other designs, some of them fatally flawed with an offset between the centre of gravity and thrust line, risking a Power Push-Over (PPO or bunt-over) causing death to the pilot and giving gyroplanes in general a poor reputation - in contrast to Cierva's original intention and early statistics. Most new autogyros are now safe from PPO.

Certification by national aviation authorities

US certification

A certificated autogyro must meet mandated stability and control criteria; in the United States these are set forth in ''Federal Aviation Regulations Part 27: Airworthiness Standards: Normal Category Rotorcraft''. The U.S. Federal Aviation Administration issues a Standard Airworthiness Certificate to qualified autogyros. Amateur-built or kit-built aircraft are operated under a Special Airworthiness Certificate in the Experimental category. Per FAR 1.1, the FAA uses the term "gyroplane" for all autogyros, regardless of the type of Airworthiness Certificate.

UK certification

Some autogyros, such as the Rotorsport MT03, have type approval by the United Kingdom Civil Aviation Authority (CAA) under British Civil Airworthiness Requirements CAP643 Section T. Others operate under a permit to fly issued by the Popular Flying Association– similar to the US experimental aircraft certification. However, the CAA's assertion that autogyros have a poor safety record means that permit to fly will only be granted to existing types of autogyro. All new types of autogyro must be submitted for full type approval under CAP643 Section T.

In 2005, the CAA issued a mandatory permit directive (MPD) which restricted operations for single seat autogryos, and were subsequently integrated into CAP643 Issue 3 published on 12 August 2005. The restrictions are concerned with the offset between the centre of gravity and thrust line, and apply to all aircraft unless evidence is presented to the CAA that the CG/Thrust Line offset less than 2 inches (5 cm) in either direction. The restrictions are summarised as follows:

Aircraft with a cockpit/nacelle may only be operated by pilots with more than 50 hours solo flight experience following the issue of their licence.

Open frame aircraft are restricted to a minimum speed of 30 mph (26 knots), except in the flare.

All aircraft are restricted to a Vne of 70 mph (61 knots)

Flight is not permitted when surface winds exceed 17 mph (15 knots) or if the gust spread exceeds 12 mph (10 knots)

Flight is not permitted in moderate, severe or extreme turbulence and airspeed must be reduced to 63 mph (55 knots) if turbulence is encountered mid-flight.

World records

In 1931, Amelia Earhart flew a Pitcairn PCA-2 to a women's world altitude record of 18,415 ft (5,613 m).

Wing Commander Ken Wallis has held most of the autogyro world records during his autogyro flying career. These include the speed record of 186 km/h (111.7 mph), and the straight-line distance record of 869.23 km (543.27 miles). On 16 November 2002, at 89 years of age, Wallis increased the 3 km speed record to 207.7 km/h (129.1 mph) - and simultaneously set another world record as the oldest pilot to set a world record.

The autogyro is one of the last remaining types of aircraft which has not yet been used to circumnavigate the globe. Expedition Global Eagle was the first attempt in history to circumnavigate the globe using an autogyro. The expedition set the record for the longest flight over water by an autogyro during the segment from Muscat, Oman to Karachi. The attempt was finally abandoned because of bad weather after a trip totalling .

In February 2003, a year before the circumnavigation attempt, the ''Global Eagle'' piloted by Warrant Officer Barry Jones also broke the world range record by flying non-stop from Culdrose in Cornwall to Wick in Scotland, a total of 580 miles (928 km) breaking the old record held by Wing Commander Ken Wallis.

Andrew Keech made a transcontinental flight from Kitty Hawk, North Carolina to San Diego, California in October 2003 and set 3 world records for speed over a recognized course. The 3 records were verified by tower personnel or by official observers of the United States' National Aeronautic Association (NAA). On 9 February 2006, he broke two of his world records and set a record for distance, ratified by the Fédération Aéronautique Internationale (FAI); Speed over a closed circuit of without payload: , speed over a closed circuit of without payload: , and distance over a closed circuit without landing: .

Notable appearances in media

An indication of the pre-World War II popularity of the autogyro, its subsequent decline and later rise of interest can be inferred from its appearances in the films and comics of the day. Notable appearances include:

In the film ''International House'' (1933), W. C. Fields's character flies around the globe in his autogyro ''The Spirit of Brooklyn''.

In the film ''It Happened One Night'' (1934), the groom and pilot King Westley arrives dramatically for the wedding in an autogyro.

Batman's first aircraft was an autogyro. The "Batgyro" was introduced in ''Detective Comics'' #31 in September 1939. It only made three appearances before being replaced by a more conventional fixed-wing aircraft.

In the classic science fiction film of H.G. Wells' ''Things to Come'' (1936), the heroes of the story arrive dramatically at the Space Gun in an Art Deco-style autogyro (at 83m), to mitigate the destruction of the Space Gun by extremists, which will carry two people to the Moon in the year 2036. The autogyro in the film was designed by celebrated art deco designer Norman Bel Geddes, who assisted production designer William Cameron Menzies on the look of the world of tomorrow.

Fictional comic characters Doc Savage, and The Shadow featured autogyros in their 1930s and 1940s pulp magazine adventures, as did Tom Strong in his pulp styled comic.

More recent notable appearances include: ''Little Nellie'', the autogyro featured in the 1967 James Bond film ''You Only Live Twice'', was a Ken Wallis WA-116 design and was piloted by Wallis in its film scenes. In the film it was shipped by Q in four suitcases and assembled before use. A Wallis WA-116T two seat autogyro is flown by character Ben Driscoll in an episode of the 1979 USA NBC-TV television science-fiction film ''The Martian Chronicles''. An autogyro was heavily featured in the second ''Mad Max (The Road Warrior)'' film, released in 1981, appearing in several scenes with its pilot, the Gyro Captain, as a major character. The pilot used in the flying sequences was Gerry Goodwin, doubling for the actor, Bruce Spence.

See also

Carter Copter

Fairey Rotodyne

Gyrodyne

Gyroglider

Helicopter

List of autogyro models

Piasecki Aircraft Corporation

Rotary-wing hang glider

References

''Rotorcraft Flying Handbook, FAA Manual H-8083-21'', Chapters 15-22. Washington, DC: Flight Standards Service, Federal Aviation Administration, U.S. Dept. of Transportation, 2001. ISBN 1-56027-404-2.

External links

Air & Space 18A gyroplane.

Australian Sport Rotorcraft Association

British Rotorcraft Association

Gyroplane/ Gyrocopter/ Autogyro/ Autogiro FAQ, Frequently Asked Questions on gyroplanes

The Gyrobee, and ultralight autogyro

Bensen Aircraft, Historic website for Bensen Gyrocopter plans, videos, pictures and more.

GyroPilot, for people interested in autogyros

Gyroplane Passion All things relating to gyroplanes

Jeff Lewis' in-depth history of the Autogyro

Popular Rotorcraft Association (United States)

gyrowiki.com Gyroplane Articles and resources.

Golden Age Pioneers: Juan de la Cierva (Inventor of the autogyro), courtesy of Bomberguy

"Will Autogiro Banish Present Plane?", March 1931, pg 28

"Feathering Of Blades Increase Gyro's Speed", April 1932, Popular Mechanics

* Category:Aircraft configurations Category:Spanish inventions

ar:أوتوجايرو ast:Autoxiru bs:Žirokopter ca:Autogir cs:Vírník da:Gyroplan de:Tragschrauber es:Autogiro eo:Aŭtogiro fa:هواچرخ fr:Autogire ko:오토자이로 hr:Žirokopter id:Otogiro it:Autogiro he:אוטוג'ירו la:Autogyrus lt:Malūnsparnis ms:Autogiro nl:Autogyro ja:オートジャイロ no:Autogyro pl:Wiatrakowiec pt:Autogiro ru:Автожир sr:Аутожир sh:Autožir fi:Autogiro sv:Autogiro uk:Автожир zh:自轉旋翼機

Wing Commander Kenneth Horatio Wallis MBE, DEng (hc), CEng, FRAeS, FSETP, PhD (hc), RAF (Ret'd), is one of the leading exponents of autogyros. He has held (in some cases still holds) 34 records relating to them.

Early life

Born on 26 April 1916 at Ely, Cambridgeshire, Ken Wallis developed a practical interest in mechanics, building a motorcycle at the age of 11. In 1936, he was inspired by a demonstration by Henri Mignet of his Mignet HM.14 Pou-du-Ciel ("Flying Flea"). Using only Mignet's book, he gathered the materials required, and started to build his own Flying Flea. He abandoned construction due to widespread adverse publicity about fatal accidents that implicated inadequate design of the type.

He took an interest in powerboating which he kept up until 1957, when he won the long Missouri Marathon.

Military career

Wallis was keen to join the RAF, and applied for their Volunteer Reserve Service, but he was turned down due to a defective right eye. Consequently he bought a private flying licence which required only a certificate signed by his GP. He obtained his A License for dual and solo flying in a record 12 hours. In 1938, Wallis tried to join the RAF again, this time with the newly formed RAF Short Service Commission Scheme, but again failed the eyetest. In 1939, he was called up to RAF Uxbridge, and again was sent for a medical. When it came to the eyesight test he managed to pass, as Wallis later recalled, "I did the first line with my good eye then they covered it up and asked me to read the bottom line with my bad eye, without them realising I just turned my head slightly so I could again see with my good eye – I passed it with Above Average Eye Sight!"

His military career started with Westland Lysander patrols in the RAF. In 1942, he was transferred to RAF Bomber Command, flying Wellingtons near Grimsby. He subsequently served in Italy and on secondment to the US Strategic Air Command, where he flew the massive Convair B-36, that had six piston engines and four auxiliary jet engines. Thereafter, he was involved in research and development, and was awarded a number of patents on his inventions. He left the RAF in 1964, retiring to Norfolk.

Autogyros

He produces autogyros for, in his own words, "reconnaissance, research & development, surveillance and military purposes", and his designs are not available for enthusiasts as he considers that although the design is simple it has to be built to the appropriate standards.

His contribution to autogyro design includes the "offset gimbal rotor head".

He flew one of his WA-116s named ''Little Nellie'' in the James Bond film ''You Only Live Twice''.

Production was at Cambridge by "Wallis Autogyros Ltd." run by his cousin.

In 1970, Wallis provided camera footage from one of his autogyros in a search for the Loch Ness Monster.

In 1970 it was announced that Airmark would produce his autogyro design with a certificate of airworthiness (C of A), that being essential for commercial use of the autogyro. Expected price was around £3000.

Between 2006 and 2009, Wallis took part in filming for Into the Wind, a documentary by Steven Hatton featuring the experiences and memories of wartime members of Bomber Command. The film, due for release in 2011, features Wallis demonstrating several of his autogyro designs.

He is President of the Norfolk and Suffolk Aviation Museum, and Patron of the Wolf Preservation Foundation.

Autogyros and aircraft

Wallbro Monoplane Replica

Wallis WA-116 Agile

Wallis WA-117

Wallis WA-118 Meteorite

Wallis WA-119

Wallis WA-120

Wallis WA-121

Recognition

Wing Commander Wallis has been the recognized world record holder for many categories of autogyro records over the years, and is also recognized as the oldest pilot to set a world flight record at the age of 89. Ken Wallis has held most of the autogyro world records during his autogyro flying career. These include the Fédération Aéronautique Internationale speed record of 186 km/h (111.7 mph), and the straight-line distance record of 869.23 km (543.27 miles). On 16 November 2002, at 89 years of age, Wallis increased the speed record to 207.7 km/h (129.1 mph).

He received the MBE in 1996.

See also

Little Nellie 007

Notes

References

Hancock, Ian. 2010. ''The Lives of Ken Wallis: Engineer and Aviator Extraordinaire''. 5th edition. Ian Hancock ISBN 978-0954123963

War veteran reaches for the skies, BBC News, 14 December 2000

Ken Wallis Tribute Page

That magnificent man in his flying machine, Patrick Barkham, The Guardian, 10 August 2010

Category:1916 births Category:Living people Category:People from Ely, Cambridgeshire Category:English aviators Category:Royal Air Force officers Category:Royal Air Force personnel of World War II Category:British World War II pilots Category:Members of the Order of the British Empire Category:Segrave Trophy recipients Category:Fellows of the Royal Aeronautical Society