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37-649: The Bell 207 Sioux Scout is a modified Bell 47 helicopter, developed by Bell Helicopter under contract from the United States Army , as a proof-of-concept demonstrator for the Bell D-255 helicopter gunship design, featuring a tandem cockpit , stub wings , and a chin-mounted gun turret . After several years of development, Bell displayed the mockup of its D-255 "Iroquois Warrior" to Army officials in June 1962, hoping to solicit funding for further development. The D-255

74-538: A semi-monocoque is a hybrid combining a tensile stressed skin and a compressive structure made up of longerons and ribs or frames . Other semi-monocoques, not to be confused with true monocoques, include vehicle unibodies , which tend to be composites, and inflatable shells or balloon tanks , both of which are pressure stabilised. Early aircraft were constructed using frames, typically of wood or steel tubing, which could then be covered (or skinned ) with fabric such as Irish linen or cotton . The fabric made

111-514: A combination of castings and sheet-metal stampings". Single-piece carbon fiber bicycle frames are sometimes described as monocoques; however as most use components to form a frame structure (even if molded in a single piece), these are frames not monocoques, and the pedal-cycle industry continues to refer to them as framesets. The P40DC, P42DC and P32ACDM all utilize a monocoque shell. Various rockets have used pressure-stabilized monocoque designs, such as Atlas and Falcon 1 . The Atlas

148-486: A frame. This reduces weight for a given amount of armour. Examples include the German TPz Fuchs and RG-33 . French industrialist and engineer Georges Roy attempted in the 1920s to improve on the bicycle-inspired motorcycle frames of the day, which lacked rigidity. This limited their handling and therefore performance. He applied for a patent in 1926, and at the 1929 Paris Automotive Show unveiled his new motorcycle,

185-406: A fuel tank incorporated into the frame. A monocoque-framed motorcycle was developed by Spanish manufacturer Ossa for the 1967 Grand Prix motorcycle racing season . Although the single-cylinder Ossa had 20 horsepower (15 kW) less than its rivals, it was 45 pounds (20 kg) lighter and its monocoque frame was much stiffer than conventional motorcycle frames , giving it superior agility on

222-568: A gunsight and turret controls located in the center, so the flying controls were moved to the side of the front cockpit. The gunner controlled a chin-mounted gun turret with twin 7.62 mm (.308 in) M60 machine guns. The stub wings held external fuel tanks. First flown on 27 June 1963, the Bell 207 demonstrated improved manoeuvrability over the Bell 47/OH-13 , derived from the stub wings. A variety of different wings, cowlings and tail surfaces were tested on

259-413: A minor structural contribution in tension but none in compression and was there for aerodynamic reasons only. By considering the structure as a whole and not just the sum of its parts, monocoque construction integrated the skin and frame into a single load-bearing shell with significant improvements to strength and weight. To make the shell, thin strips of wood were laminated into a three dimensional shape;

296-430: A new forward fuselage and Bell 47G-3 dynamic parts fitted to a Bell 47J center and rear fuselage. The Sioux Scout included all the key features of a modern helicopter gunship – a tandem cockpit , stub wings for weapons, and a chin-mounted gun turret . The tandem cockpit placed the gunner in the lower front seat with the pilot in the rear, with both crew positions featuring flight controls. The gunner's position featured

333-399: A solid frame. This becomes obvious when internal pressure is lost and the structure collapses. Monocoque tanks can also be cheaper to manufacture than more traditional orthogrids . Blue Origin's upcoming New Glenn launch vehicle will use monocoque construction on its second stage despite the mass penalty in order to reduce the cost of production. This is especially important when the stage

370-506: A technique adopted from boat hull construction. One of the earliest examples was the Deperdussin Monocoque racer in 1912, which used a laminated fuselage made up of three layers of glued poplar veneer, which provided both the external skin and the main load-bearing structure. This also produced a smoother surface and reduced drag so effectively that it was able to win most of the races it was entered into. This style of construction

407-440: A true monocoque carries both tensile and compressive forces within the skin and can be recognised by the absence of a load-carrying internal frame. Few metal aircraft other than those with milled skins can strictly be regarded as pure monocoques, as they use a metal shell or sheeting reinforced with frames riveted to the skin, but most wooden aircraft are described as monocoques, even though they also incorporate frames. By contrast,

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444-555: A uniform material. After failed attempts with several large flying boats in which a few components were monocoques, he built the Zeppelin-Lindau V1 to test out a monocoque fuselage. Although it crashed, he learned a lot from its construction. The Dornier-Zeppelin D.I was built in 1918 and although too late for operational service during the war was the first all metal monocoque aircraft to enter production. In parallel to Dornier, Zeppelin also employed Adolf Rohrbach , who built

481-566: A variety of versions and under different designations for three decades. It was designated H-13 Sioux by the US Army , and during the Korean War , it served a variety of roles, including reconnaissance and scouting, search and rescue, and medevac. The "Telecopter" was a Bell 47 rented by television station KTLA in Los Angeles , California . It was outfitted with a television camera and it made

518-649: Is a single-rotor single-engine light helicopter manufactured by Bell Helicopter . It was based on the third Bell 30 prototype, which was the company's first helicopter designed by Arthur M. Young . The 47 became the first helicopter certified for civilian use on 8 March 1946. The first civilian delivery was made on 31 December 1946 to Helicopter Air Transport . More than 5,600 Bell 47s were produced, including those under license by Agusta in Italy, Kawasaki Heavy Industries in Japan, and Westland Aircraft in

555-459: The Junkers J 1 had appeared as early as 1915, these were not monocoques but added a metal skin to an underlying framework. The first metal monocoques were built by Claudius Dornier , while working for Zeppelin-Lindau. He had to overcome a number of problems, not least was the quality of aluminium alloys strong enough to use as structural materials, which frequently formed layers instead of presenting

592-693: The Zeppelin-Staaken E-4/20 , which when it flew in 1920 became the first multi-engined monocoque airliner, before being destroyed under orders of the Inter-Allied Commission. At the end of WWI, the Inter-Allied Technical Commission published details of the last Zeppelin-Lindau flying boat showing its monocoque construction. In the UK, Oswald Short built a number of experimental aircraft with metal monocoque fuselages starting with

629-427: The 1920 Short Silver Streak in an attempt to convince the air ministry of its superiority over wood. Despite advantages, aluminium alloy monocoques would not become common until the mid 1930s as a result of a number of factors, including design conservatism and production setup costs. Short would eventually prove the merits of the construction method with a series of flying boats, whose metal hulls didn't absorb water as

666-510: The 207 before it was turned over to the Army pilots at Fort Benning , Georgia for further testing at the end of 1963. After evaluating the Sioux Scout in early 1964, the Army was impressed, but also felt the Sioux Scout was undersized, underpowered, and generally not suited for practical use. Later in 1964, the Army requested proposals for its Advanced Aerial Fire Support System (AAFSS). Bell proposed

703-488: The Aero-D One, featuring a composite monocoque chassis that weighed only 12 kg (26 lb). An aluminium monocoque frame was used for the first time on a mass-produced motorcycle from 2000 on Kawasaki's ZX-12R , their flagship production sportbike aimed at being the fastest production motorcycle . It was described by Cycle World in 2000 as a "monocoque backbone ... a single large diameter beam" and "Fabricated from

740-509: The Art-Deco styled 1930 Majestic. Its new type of monocoque body solved the problems he had addressed, and along with better rigidity it did double-duty, as frame and bodywork provided some protection from the elements. Strictly considered, it was more of a semi-monocoque, as it used a box-section, pressed-steel frame with twin side rails riveted together via crossmembers, along with floor pans and rear and front bulkheads. A Piatti light scooter

777-678: The D-262, a smaller version of the D-255, making better use of the T53 engine from the UH-1. However, the Bell D-262 was not selected as a finalist in the competition, which was won by the abortive Lockheed AH-56 Cheyenne . Data from General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Bell 47 The Bell 47

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814-567: The G series. It was sold throughout Asia, and some were used in Australia. In February 2010, the Bell 47 type certificates were transferred to Scott's Helicopter Services . The sister company that was formed, Scott's - Bell 47 , is in the process of starting production of a turboshaft powered version of the Bell 47, the 47GT-6, using a Rolls-Royce RR300 engine and with composite rotor blades, with deliveries planned from 2016. The Bell 47 entered US military service in late 1946, and operated in

851-1017: The Moon. The 47 has also served as the helicopter of choice for basic helicopter flight instruction in many countries. Agusta A.115 1971 Italian prototype of a Bell 47J with an unclad, tubular tail boom, and powered by a Turbomeca Astazou II turboshaft engine Meridionali/Agusta EMA 124 Italian prototype with redesigned forward fuselage. Not produced. Kawasaki KH-4 Japanese production version with redesigned, lengthened cabin, and redesigned control system Carson Super C-4 El Tomcat Mk.II Bell 47G-2 modified extensively for agricultural spraying by Continental Copters Inc. First flew in April 1959, followed by further improved versions. Data from International Directory of Civil Aircraft General characteristics Performance Related development Aircraft of comparable role, configuration, and era Related lists Monocoque First used for boats,

888-479: The United Kingdom. The Bell 47J Ranger is a modified version with a fully enclosed cabin and tail boom. Early models varied in appearance, with open cockpits or sheet metal cabins, fabric covered or open structures, some with four-wheel landing gear. Later model D and Korean War H-13D and E types settled on a more utilitarian style. The most common model, the 47G introduced in 1953, can be recognized by

925-453: The full "soap bubble" canopy , exposed welded-tube tail boom, saddle fuel tanks and skid landing gear. The later three-seat 47H had an enclosed cabin with full cowling and monocoque tail boom. It was an attempt to market a "luxury" version of the basic 47G. Relatively few were produced. Engines were Franklin or Lycoming vertically mounted piston engines of 175 to 305 HP (130 to 227 kW ). Seating varied from two (early 47s and

962-679: The later G-5A) to four (the J and KH-4). In April 2011 there were 1068 registered with the Federal Aviation Administration in the United States and 15 in the United Kingdom. Bell 47s were produced in Japan by a Bell and Kawasaki venture; this led to the Kawasaki KH-4 variant, a four-seat version of the Model 47 with a cabin similar to the Bell 47J. It differed from the "J" in having a standard uncovered tail boom and fuel tanks like

999-620: The problem overnight, the Telecopter made the world's first successful television news flight on July 4, 1958. The National Aeronautics and Space Administration (NASA) had a number of Bell 47s during the Apollo program , used by astronauts as trainers for the lunar lander . Apollo 17 commander Eugene Cernan had a nearly disastrous crash into the Indian River in Florida in 1971, before his flight to

1036-463: The racetrack. Ossa won four Grands Prix races with the monocoque bike before their rider died after a crash during the 250 cc event at the 1970 Isle of Man TT , causing the Ossa factory to withdraw from Grand Prix competition. Notable designers such as Eric Offenstadt and Dan Hanebrink created unique monocoque designs for racing in the early 1970s. The F750 event at the 1973 Isle of Man TT races

1073-410: The unibody system (also referred to as unitary construction, unitary body–chassis or body–frame integral construction), in which the body of the vehicle, its floor pan, and chassis form a single structure, while the skin adds relatively little strength or stiffness. Some armoured fighting vehicles use a monocoque structure with a body shell built up from armour plates, rather than attaching them to

1110-458: The wooden hulls did, greatly improving performance. In the United States, Northrop was a major pioneer, introducing techniques used by his own company and Douglas with the Northrop Alpha . In motor racing, the safety of the driver depends on the car body, which must meet stringent regulations, and only a few cars have been built with monocoque structures. An aluminum alloy monocoque chassis

1147-474: The world ' s first flight by a television news helicopter on July 3, 1958, with its inventor, John D. Silva, aboard. When the television station reported it was receiving no video, Silva exited the helicopter ' s cockpit to climb onto its landing skid while it hovered at 1,500 feet (457 m) so he could investigate the microwave transmitter bolted to its side, where he discovered a vacuum tube had failed due to vibration and hot weather. After Silva fixed

Bell 207 Sioux Scout - Misplaced Pages Continue

1184-465: Was first used in the 1962 Lotus 25 Formula 1 race car and McLaren was the first to use carbon-fiber-reinforced polymers to construct the monocoque of the 1981 McLaren MP4/1 . In 1990 the Jaguar XJR-15 became the first production car with a carbon-fiber monocoque. The term monocoque is frequently misapplied to unibody cars. Commercial car bodies are almost never true monocoques but instead use

1221-481: Was further developed in Germany by LFG Roland using the patented Wickelrumpf (wrapped hull) form later licensed by them to Pfalz Flugzeugwerke who used it on several fighter aircraft. Each half of the fuselage shell was formed over a male mold using two layers of plywood strips with fabric wrapping between them. The early plywood used was prone to damage from moisture and delamination. While all-metal aircraft such as

1258-547: Was planned to be a purpose-built attack helicopter based on the UH-1B airframe and dynamic components with a new, slender airframe and a two-seat, tandem cockpit, featuring a grenade launcher in a ball turret on the nose, a 20 mm belly-mounted gun pod, and stub wings for mounting rockets or SS.10 anti-tank missiles . A proof-of-concept contract was awarded to Bell in December 1962 for the Model 207 Sioux Scout, which was, in essence,

1295-426: Was produced in the 1950s using a monocoque hollow shell of sheet-steel pressings welded together, into which the engine and transmission were installed from underneath. The machine could be tipped onto its side, resting on the bolt-on footboards for mechanical access. A monocoque framed scooter was produced by Yamaha from 1960–1962. Model MF-1 was powered by a 50 cc engine with a three-speed transmission and

1332-436: Was very light since a major portion of its structural support was provided by its single-wall steel balloon fuel tanks , which hold their shape while under acceleration by internal pressure. Balloon tanks are not true monocoques but act in the same way as inflatable shells . A balloon tank skin only handles tensile forces while compression is resisted by internal liquid pressure in a way similar to semi-monocoques braced by

1369-505: Was won by Peter Williams on the monocoque-framed John Player Special that he helped to design based on Norton Commando . Honda also experimented with the NR500 , a monocoque Grand Prix racing motorcycle in 1979 . The bike had other innovative features, including an engine with oval shaped cylinders, and eventually succumbed to the problems associated with attempting to develop too many new technologies at once. In 1987 John Britten developed

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