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Tandem-rotor Helicopter
A tandem-rotor aircraft is an aircraft with two large helicopter rotor assemblies mounted one in front of the other in the horizontal plane. This configuration is mainly used for large cargo helicopters. Such aircraft are often informally referred to as "Chinooks," after the CH-47 Chinook, one of the first widely adopted heavy-lift helicopters with a tandem-rotor configuration. Design Single-rotor helicopters need a mechanism to neutralize the Aircraft principal axes, yawing movement produced by the single large rotor. This is commonly accomplished by a tail rotor, coaxial rotors, and the NOTAR systems. Tandem-rotor helicopters, however, use counter-rotating rotors, with each cancelling out the other's torque. Therefore, all of the power from the engines can be used for lift (force), lift, whereas a single-rotor helicopter uses some of the engine power to counter the torque. An alternative is to mount two rotors in a Coaxial rotors, coaxial configuration. The first successful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CH-46 Sea Knight Helicopter
The Boeing Vertol CH-46 Sea Knight is an American medium-lift tandem rotors, tandem-rotor transport helicopter powered by twin turboshaft aircraft engine, engines. It was designed by Piasecki Helicopter, Vertol and manufactured by Boeing Helicopters, Boeing Vertol following Vertol's acquisition by Boeing. Development of the Sea Knight, which was originally designated by the firm as the Vertol Model 107, commenced during 1956. It was envisioned as a successor to the first generation of rotorcraft, such as the Piasecki H-21, H-21 "Flying Banana", that had been powered by Reciprocating engine, piston engines; in its place, the V-107 made use of the emergent turboshaft engine. On 22 April 1958, the V-107 prototype performed its maiden flight. During June 1958, the US Army awarded a contract for the construction of ten production-standard aircraft, designated as the YHC-1A, based on the V-107; this initial order was later cut down to three YHC-1As. During 1961, the United States Mari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission (mechanics)
A transmission (also called a gearbox) is a mechanical device invented by Louis Renault (industrialist), Louis Renault (who founded Renault, Renault) which uses a gear set—two or more gears working together—to change the speed, direction of rotation, or torque multiplication/reduction in a machine. Transmissions can have a single fixed-gear ratio, multiple distinct gear ratios, or continuously variable ratios. Variable-ratio transmissions are used in all sorts of machinery, especially vehicles. Applications Early uses Early transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engine, steam-powered devices. Applications of these devices included pumps, mill (grinding), mills and Hoist (device), hoists. Bicycles Bicycles traditionally have used hub gear or Derailleur gear transmissions, but there are other more recent design innovations. Automobiles Since the torque and Horsepower, power output of an interna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Vertol XCH-62
The Boeing Vertol XCH-62 (Model 301) was a triple-turbine, heavy-lift helicopter project designed for the United States Army by Boeing Rotorcraft Systems, Boeing Vertol. Approved in 1971, one prototype reached 95% completion before it was canceled in 1975. The prototype was scrapped in 2005. Development While the CH-47 Chinook is a large helicopter by American standards, its payload of is dwarfed by the huge Soviet-Russian heavy-lift helicopters such as the Mil Mi-26, with payload, and the experimental Mil V-12, with payload. For a long time Boeing and the US military had an urge to match or top the Mil heavy lifters. In the late 1960s, Boeing came up with designs for machines with broad similarities to the Sea Knight and Chinook, but about twice the size of the Chinook in terms of linear dimensions. Proposed machines included the "Model 227" transport and the "Model 237" flying crane. The U.S. Department of Defense (DoD) issued a request for proposal (RFP) for a Heavy Lift ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Vertol CH-46 Sea Knight
The Boeing Vertol CH-46 Sea Knight is an American medium-lift tandem rotors, tandem-rotor transport helicopter powered by twin turboshaft aircraft engine, engines. It was designed by Piasecki Helicopter, Vertol and manufactured by Boeing Helicopters, Boeing Vertol following Vertol's acquisition by Boeing. Development of the Sea Knight, which was originally designated by the firm as the Vertol Model 107, commenced during 1956. It was envisioned as a successor to the first generation of rotorcraft, such as the Piasecki H-21, H-21 "Flying Banana", that had been powered by Reciprocating engine, piston engines; in its place, the V-107 made use of the emergent turboshaft engine. On 22 April 1958, the V-107 prototype performed its maiden flight. During June 1958, the US Army awarded a contract for the construction of ten production-standard aircraft, designated as the YHC-1A, based on the V-107; this initial order was later cut down to three YHC-1As. During 1961, the United States Mari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Vertol 107-II
The Boeing Vertol CH-46 Sea Knight is an American medium-lift tandem-rotor transport helicopter powered by twin turboshaft engines. It was designed by Vertol and manufactured by Boeing Vertol following Vertol's acquisition by Boeing. Development of the Sea Knight, which was originally designated by the firm as the Vertol Model 107, commenced during 1956. It was envisioned as a successor to the first generation of rotorcraft, such as the H-21 "Flying Banana", that had been powered by piston engines; in its place, the V-107 made use of the emergent turboshaft engine. On 22 April 1958, the V-107 prototype performed its maiden flight. During June 1958, the US Army awarded a contract for the construction of ten production-standard aircraft, designated as the YHC-1A, based on the V-107; this initial order was later cut down to three YHC-1As. During 1961, the US Marine Corps (USMC), which had been studying its requirements for a medium-lift, twin-turbine cargo/troop assault helicop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Model 360
The Boeing Model 360 is an American experimental medium-lift tandem rotor cargo helicopter developed privately by Boeing to demonstrate advanced helicopter technology. The aircraft was intended as a technology demonstrator, with no plans to put the type into production, and many of its design features were carried onto other programs including the RAH-66 Comanche and V-22 Osprey. The sole prototype has been preserved and is a static exhibit at the American Helicopter Museum in West Chester, Pennsylvania. Design and development Boeing Vertol developed its Model 360 in the 1980s as a technology demonstrator with company funds. It was a new design and made significant use of composites. The Boeing Model 360 differed from its brethren CH-46 and CH-47 tandem rotor helicopters by incorporating extensive amounts of composite materials in structural and dynamic components, namely in advanced rotor heads composed of fiberglass and graphite composites, along with graphite fuselage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing CH-47 Chinook
The Boeing CH-47 Chinook is a tandem-rotor helicopter originally developed by American rotorcraft company Piasecki Helicopter, Vertol and now manufactured by Boeing Defense, Space & Security. The Chinook is a Military transport helicopter, heavy-lift helicopter that is among the heaviest lifting Western helicopters. Its name, Chinook, is from the Native Americans in the United States, Native American Chinook people of Oregon and Washington (state), Washington state. The Chinook was originally designed by Vertol, which had begun work in 1957 on a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. Around the same time, the United States Department of the Army announced its intention to replace the Radial engine, piston-engine–powered Sikorsky CH-37 Mojave with a new, gas turbine–powered helicopter. During June 1958, the U.S. Army ordered a small number of V-107s from Vertol under the ''YHC-1A'' designation; following testing, some Army officials consider ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell HSL
The Bell HSL (Model 61) was an American 1950s anti-submarine warfare (ASW) helicopter built by the Bell Helicopter company, the only tandem rotors, tandem rotor type designed by Bell. It had its first flight in 1953 and entered service with the U.S. Navy in 1957. Over 50 models were produced but it was out of service by 1960 - such was the pace of helicopter development in this period. The helicopter had two main rotors at either end of the fuselage tube, linked by a transmission but powered by a single Pratt & Whitney R-2800-50m, which was an 18-cylinder air-cooled radial engine. The front rotor shaft was actually slightly ahead of pilots in the front cockpit. Design and development The prototype Bell Model 61 first flew on 3 March 1953; it had been designed to meet a United States Navy requirement for an anti-submarine warfare helicopter. In June 1950 in aviation, 1950, the Model 61 was announced as the winner of the competition, and three XHSL-1 evaluation aircraft were ordered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
