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18-492: The use of directed air to provide anti-torque control had been tested as early as 1945 in the British Cierva W.9 . During 1957, a Spanish prototype designed and built by Aerotecnica flew using exhaust gases from the turbine instead of a tail rotor. This model was designated as Aerotecnica AC-14 . The Fiat 7005 used a pusher propeller that blew against a cascade of tail vanes at the rear of its fuselage. Development of

36-567: A chase aircraft for the Apache. Although the concept took over three years to refine, the NOTAR system is simple in theory and works to provide some directional control using the Coandă effect . A variable pitch fan is enclosed in the aft fuselage section immediately forward of the tail boom and driven by the main rotor transmission. This fan forces low pressure air through two slots on the right side of

54-549: A variety of 3rd party factories in order to be able to quickly produce new designs on demand. These factories joined ones being run by the government directly. In total over 40 companies joined the group when it officially formed on 23 March 1916. In the post-war era the group expanded to include almost every aircraft company and those related to it—engine manufacturers, metal alloy companies, etc. Since this period they have often been referred to by acronym , SBAC . They were also instrumental in approaching Lloyd's of London to start

72-403: The NOTAR system dates back to 1975, when engineers at Hughes Helicopters began concept development work. On December 17, 1981, Hughes flew an OH-6A fitted with NOTAR for the first time. The OH-6A helicopter (serial number 65-12917) was supplied by the U.S. Army for Hughes to develop the NOTAR technology and was the second OH-6 built by Hughes for the U.S. Army. A more heavily modified version of

90-451: The W.9 was torque compensation and directional control by using blown air rather than a tail rotor. A variable pitch fan cooled the engine; the heated air and engine exhaust passed through the long hollow tailboom and exhausted to port. Foot pedals controlled the fan pitch. Of more importance, however, was the shaft-driven hydraulically-actuated rotor hub with rotational speed variation to give automatic collective pitch control. Development of

108-525: The inspection and insurance of aircraft, which led to increased commercial aviation. In 1932 the group hosted a one-day air show and trade fair at the Hendon airfield in London on 19 June, the day after the annual RAF Hendon display. Similar one-day events were held for the next three years, but 1935 was the last Hendon RAF display. The SBAC show moved to de Havilland 's Hatfield airfield in 1936 and 1937;

126-557: The latter was both the first two-day SBAC show and the last before World War II. Immediately after the War it was held at Radlett , the home of Handley Page on 12–13 September, and early September became the regular date. In 1947 the show was again at Radlett with three flying days. In 1948 the meeting was moved to the Royal Aircraft Establishment at Farnborough and was six days long with three flying days, setting

144-661: The organisation is the British Aviation Group and the UK Space Agency . On 29 March 1915 a number of British aircraft manufacturers and industrialists met to arrange a standards body and production pooling system known as the Society of British Aircraft Constructors . Notable among the aircraft participants were Herbert Austin , Frederick Handley Page , H.V. Roe of Avro , and E.B. Parker of Short Brothers . The group agreed to share their designs among

162-577: The pattern for the future. The Farnborough shows were held annually as trade fairs for British manufacturers and with two public days, the Saturday and Sunday, throughout the 1950s. Crowds were large: on the last day, the Sunday of the 1954 show some 160,000 people attended. In 1962 the British-only rule was slightly relaxed by allowing the participation of foreign aircraft with British engines. 1962

180-582: The prototype demonstrator first flew in March 1986 (by which time McDonnell Douglas had acquired Hughes Helicopters). The original prototype last flew in June 1986 and is now at the U.S. Army Aviation Museum in Fort Novosel , Alabama . A production model NOTAR 520N (N520NT) was later produced and first flew on May 1, 1990. It collided with an Apache AH-64D and crashed on September 27, 1994 while flying as

198-414: The quietest helicopters certified by FAA . There are several production helicopters that utilize the NOTAR system, which are produced by MD Helicopters : Cierva W.9 The Cierva W.9 was a British 1940s experimental helicopter with a three-blade tilting-hub controlled main rotor, and torque compensation achieved using a jet of air discharged from the rear port side of the fuselage. The design

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216-484: The rotor system resulted in a tilting hub combined with cyclic pitch control of each blade to minimize control forces. Manual control of collective pitch was added to the automatic collective pitch change system to provide precise vertical control in hover and the ability to cushion a landing from an autorotative descent. The W.9 was first publicly demonstrated during an air display in Southampton on 22 June 1946. It

234-421: The tailboom, causing the downwash from the main rotor to hug the tail boom, producing lift, and thus a measure of directional control. This is augmented by a direct jet thruster and vertical stabilisers. Benefits of the NOTAR system include increased safety (the tail rotor being vulnerable), and greatly reduced external noise as tail rotors on helicopters produce a lot of noise. NOTAR-equipped helicopters are among

252-667: Was also the last of the annual shows, the next being held in 1964 and thenceforth biennially; in 1968 European manufacturers were invited. In 1974 the show accepted international participation and from 1978 it became known as the Farnborough International . Since 1964 the Farnborough has alternated with the Paris Air Show . The name changed from "Society of British Aircraft Constructors" to "Society of British Aerospace Companies" in 1964. SBAC Scotland

270-507: Was both safer and more efficient than the Sikorsky R-4 helicopter fitted with manually controlled main rotor cyclic and collective pitch and the anti-torque tail rotor system. The W.9 was completed late in 1944 and assigned serial PX203 . It was damaged during ground-running due to incorrect control phasing arising from a high order of pitch-flap coupling, and did not start test flying until 1945 . The most visible characteristic of

288-800: Was displayed at the Seventh SBAC Airshow at Radlett in 1946 The helicopter was destroyed in an accident in 1946 and the project was abandoned. Parts of the W.9 rotor hub were used in the W.14 Skeeter prototype. Cierva was bought out by Saunders-Roe , and that design entered production service in the 1950s as the Saunders-Roe Skeeter. Data from Flight General characteristics The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985) . Orbis Publishing. Society of British Aerospace Companies The Society of British Aerospace Companies ( SBAC , formerly Society of British Aircraft Constructors )

306-444: Was not further developed into production, and the prototype crashed in 1946. In 1943, primary investor G & J Weir Ltd. revived the moribund Cierva Autogiro Company to develop an experimental helicopter to Air Ministry Specification E.16/43. The W.9 was to investigate James G. Weir's contention that a powered tilting hub-controlled rotor with automatic collective pitch control, and torque reaction control using jet efflux,

324-922: Was the UK's national trade association representing companies supplying civil air transport, aerospace defence, homeland security and space. As of October 2009 SBAC merged with the Defence Manufacturers Association and the Association of Police and Public Security Suppliers to form the ADS Group . The SBAC organises the Farnborough Airshow . With its regional partners, SBAC represents over 2,600 companies, assisting them in developing new business globally, facilitating innovation and competitiveness and providing regulatory services in technical standards and accreditation. Inside

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