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Powered-lift
A powered lift aircraft takes off and lands vertically under engine power but uses a fixed wing for horizontal flight. Like helicopters, these aircraft do not need a long runway to take off and land, but they have a speed and performance similar to standard fixed-wing aircraft in combat or other situations. Some powered-lift aircraft, like the Bell Boeing V-22 Osprey used by the United States Marines, use a tiltrotor or tiltwing. These are called a convertiplane. Others like the British Harrier jump jet use thrust vectoring or other direct thrust techniques. The first powered-lift ratings on a civilian pilot certificate were issued by the Federal Aviation Administration (FAA) on 21 August 1997 to pilots of Bell Helicopter, Boeing, and the United States Marine Corps. Definition The term is an aircraft classification used by the International Civil Aviation Organization (ICAO) and the United States' FAA: Convertiplane A convertiplane uses rotor power for vertical takeoff an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing
The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product support services. Boeing is among the largest global aerospace manufacturers; it is the third-largest defense contractor in the world based on 2020 revenue, and is the largest exporter in the United States by dollar value. Boeing stock is included in the Dow Jones Industrial Average. Boeing is incorporated in Delaware. Boeing was founded by William Boeing in Seattle, Washington, on July 15, 1916. The present corporation is the result of the merger of Boeing with McDonnell Douglas on August 1, 1997. Then chairman and CEO of Boeing, Philip M. Condit, assumed those roles in the combined company, while Harry Stonecipher, former CEO of McDonnell Douglas, became president and COO. The Boeing Company's corporate headquarters is in Chicago, Illi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotor Wing
A rotor wing is a lifting rotor or wing which spins to provide aerodynamic lift. In general, a rotor may spin about an axis which is aligned substantially either vertically or side-to-side (spanwise). All three classes have been studied for use as lifting rotors and several variations have been flown on full-size aircraft, although only the vertical-axis rotary wing has become widespread on rotorcraft such as the helicopter. Some types provide lift at zero forward airspeed, allowing for vertical takeoff and landing (VTOL), as in the helicopter. Others, especially unpowered free-spinning types, require forward airspeed in the same manner as a fixed-wing aircraft, as in the autogyro. Many can also provide forward thrust if required. Types Many ingenious ways have been devised to convert the spinning of a rotor into aerodynamic lift. The various types of such rotor wings may be classified according to the axis of the rotor. Types include:Foshag & Boehler (1969)Seifert (2012) ;Vertic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertol VZ-2
The Vertol VZ-2 (or Model 76) was a research aircraft built in the United States in 1957 to investigate the tiltwing approach to vertical take-off and landing. Design and development The aircraft had a fuselage of tubular framework (originally uncovered) and accommodation for its pilot in a helicopter-like bubble canopy. The T-tail incorporated small ducted fans to act as thrusters for greater control at low speeds. Ground tests began in April 1957 and on 13 August, the VZ-2 took off for the first time in hover mode only. On 23 July 1958, the aircraft made its first full transition from vertical flight to horizontal flight. By the time the test program ended in 1965, the VZ-2 had made some 450 flights, including 34 full transitions. The aircraft has been preserved by the National Air and Space Museum in storage at the Paul E. Garber Preservation, Restoration, and Storage Facility. Specifications See also References * * {{US Army VTOL Z-02, Vertol Tiltwing aircraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AgustaWestland AW609
The AgustaWestland (now Leonardo) AW609, formerly the Bell/Agusta BA609, is a twin-engined tiltrotor VTOL aircraft with a configuration similar to that of the Bell Boeing V-22 Osprey. It is capable of landing vertically like a helicopter while having a range and speed in excess of conventional rotorcraft. The AW609 is aimed at the civil aviation market, in particular VIP customers and offshore oil and gas operators. Development Origins and program changes The BA609 drew on experience gained from Bell's earlier experimental tiltrotor, the XV-15. In 1996, Bell and Boeing had formed a partnership to develop a civil tiltrotor aircraft; however, in March 1998, it was announced that Boeing had pulled out of the project. In September 1998, it was announced that Agusta had become a partner in the development program. This led to the establishment of the Bell/Agusta Aerospace Company (BAAC), a joint venture between Bell Helicopter and AgustaWestland, to develop and manufacture the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perpendicular
In elementary geometry, two geometric objects are perpendicular if they intersect at a right angle (90 degrees or π/2 radians). The condition of perpendicularity may be represented graphically using the ''perpendicular symbol'', ⟂. It can be defined between two lines (or two line segments), between a line and a plane, and between two planes. Perpendicularity is one particular instance of the more general mathematical concept of '' orthogonality''; perpendicularity is the orthogonality of classical geometric objects. Thus, in advanced mathematics, the word "perpendicular" is sometimes used to describe much more complicated geometric orthogonality conditions, such as that between a surface and its '' normal vector''. Definitions A line is said to be perpendicular to another line if the two lines intersect at a right angle. Explicitly, a first line is perpendicular to a second line if (1) the two lines meet; and (2) at the point of intersection the straight angle on one side ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter Rotor
A helicopter main rotor or rotor system is the combination of several rotary wings (rotor blades) with a control system, that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight. Each main rotor is mounted on a vertical mast over the top of the helicopter, as opposed to a helicopter tail rotor, which connects through a combination of drive shaft(s) and gearboxes along the tail boom. The blade pitch is typically controlled by the pilot using the helicopter flight controls. Helicopters are one example of rotary-wing aircraft (rotorcraft). The name is derived from the Greek words ''helix'', helik-, meaning spiral; and ''pteron'' meaning wing. Design principles Overview The helicopter rotor is powered by the engine, through the transmission, to the rotating mast. The mast is a cylindrical metal shaft that extends upward from—and is driven by—the transmission. At the top of the mast i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust
Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that system. The force applied on a surface in a direction perpendicular or normal to the surface is also called thrust. Force, and thus thrust, is measured using the International System of Units (SI) in newtons (symbol: N), and represents the amount needed to accelerate 1 kilogram of mass at the rate of 1 meter per second per second. In mechanical engineering, force orthogonal to the main load (such as in parallel helical gears) is referred to as static thrust. Examples A fixed-wing aircraft propulsion system generates forward thrust when air is pushed in the direction opposite to flight. This can be done by different means such as the spinning blades of a propeller, the propelling jet of a jet engine, or by ejecting hot gases from a rocket ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proprotor
A proprotor is a spinning airfoil that function as both an airplane-style propeller and a helicopter-style rotor. Several proprotor-equipped convertiplanes, such as the Bell Boeing V-22 Osprey tiltrotor, are capable of switching back and forth between flying akin to both helicopters and fixed-wing aircraft. Accordingly this type of airfoil has been predominantly applied to vertical takeoff and landing (VTOL) aircraft. The dual-role airfoil is accomplished by one of several design approaches: :*changing the angle of attack of the wing that the proprotor is attached to, from approximately zero degrees to around ninety degrees: a tiltwing aircraft, :*changing the angle of attack of only the rotor hub, and possibly the engine that drives it, as on a tiltrotor, :*changing the angle of attack of the entire aircraft, as on a tailsitter, which launches and lands on its tail. Application details On several aerial vehicles such as the AgustaWestland AW609 and V-22 Osprey, a pair of three-b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ducted Fan
In aeronautics, a ducted fan is a thrust-generating mechanical fan or propeller mounted within a cylindrical duct or shroud. Other terms include ducted propeller or shrouded propeller. When used in vertical takeoff and landing (VTOL) applications it is also known as a shrouded rotor.Kotwani, Kailash;Ducted Fan or Shrouded Rotor Aerodynamics and its Application in Miniature VTOL Aerial Vehicles, 2009. (retrieved 22 March 2022). Ducted fans are used for propulsion or direct lift in many types of vehicle including aeroplanes, airships, hovercraft, and powered lift VTOL aircraft. The high-bypass turbofan engines used on many modern airliners is an example of a very successful and popular use of ducted fan design. The duct increases thrust efficiency by up to 90% in some cases, in comparison to a similar-sized propeller in free air. Ducted fans are quieter, and offer good opportunities for thrust vectoring. The shroud offers good protection to ground personnel from accidentally cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propeller (aircraft)
An aircraft propeller, also called an airscrew,Beaumont, R.A.; ''Aeronautical Engineering'', Odhams, 1942, Chapter 13, "Airscrews". converts rotary motion from an engine or other power source into a swirling slipstream which pushes the propeller forwards or backwards. It comprises a rotating power-driven hub, to which are attached several radial airfoil-section blades such that the whole assembly rotates about a longitudinal axis. The blade pitch may be fixed, manually variable to a few set positions, or of the automatically variable "constant-speed" type. The propeller attaches to the power source's driveshaft either directly or through reduction gearing. Propellers can be made from wood, metal or composite materials. Propellers are most suitable for use at subsonic airspeeds generally below about , although supersonic speeds were achieved in the McDonnell XF-88B experimental propeller-equipped aircraft. Supersonic tip-speeds are used in some aircraft like the Tupolev Tu-95, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
