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Hawker Siddeley HS.141
The Hawker Siddeley HS.141 was a 1970s design study and submission for a British V/STOL airliner requirement.Swanborough 1971, p. 39. Designed by Hawker Siddeley Aviation and tested in wind tunnels neither prototypes nor production aircraft were produced. Design and development Outline Requirement In 1969 the British Transport Aircraft Requirements Committee (TARC) issued a design study "Outline Requirement" (OR) for a 100-seat VTOL airliner capable of a range of 450 miles (725 km).Swanborough 1971, p. 40. Emphasis was to be on noise reduction by using steep approach and departure profiles, much like those used today at London City Airport. It was thought at the time that money would be better invested on designing new aircraft types than building a third London airport. Hawker Siddeley investigated various configurations of aircraft, powerplant and control systems including an early proposal using ogival delta wings and twin fins, before submitting their draft design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V/STOL
A vertical and/or short take-off and landing (V/STOL) aircraft is an airplane able to take-off or land vertically or on short runways. Vertical takeoff and landing (VTOL) aircraft are a subset of V/STOL craft that do not require runways at all. Generally, a V/STOL aircraft needs to be able to hover. Helicopters are not considered under the V/STOL classification as the classification is only used for aeroplanes, aircraft that achieve lift (force) in forward flight by planing the air, thereby achieving speed and fuel efficiency that is typically greater than the capability of helicopters. Most V/STOL aircraft types were experiments or outright failures from the 1950s to 1970s. V/STOL aircraft types that have been produced in large numbers include the F-35B Lightning II, Harrier, Yak-38 Forger and V-22 Osprey. A rolling takeoff, sometimes with a ramp ( ski-jump), reduces the amount of thrust required to lift an aircraft from the ground (compared with vertical takeoff), and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbofan
The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which achieves mechanical energy from combustion, and the ''fan'', a ducted fan that uses the mechanical energy from the gas turbine to force air rearwards. Thus, whereas all the air taken in by a turbojet passes through the combustion chamber and turbines, in a turbofan some of that air bypasses these components. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of these contributing to the thrust. The ratio of the mass-flow of air bypassing the engine core to the mass-flow of air passing through the core is referred to as the bypass ratio. The engine produces thrust through a combination of these two portions working together; engines that use more Propelling nozzle, jet thrust relative to fan thrust are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vectored Thrust
Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the vehicle. In rocketry and ballistic missiles that fly outside the atmosphere, aerodynamic control surfaces are ineffective, so thrust vectoring is the primary means of attitude control. Exhaust vanes and gimbaled engines were used in the 1930s by Robert Goddard. For aircraft, the method was originally envisaged to provide upward vertical thrust as a means to give aircraft vertical (VTOL) or short (STOL) takeoff and landing ability. Subsequently, it was realized that using vectored thrust in combat situations enabled aircraft to perform various maneuvers not available to conventional-engined planes. To perform turns, aircraft that use no thrust vectoring must rely on aerodynamic control surfaces only, such as ailerons or elevator; aircraft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Pressure
Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone, and in water with a hydrophone. The SI unit of sound pressure is the pascal (Pa). Mathematical definition A sound wave in a transmission medium causes a deviation (sound pressure, a ''dynamic'' pressure) in the local ambient pressure, a ''static'' pressure. Sound pressure, denoted ''p'', is defined by p_\text = p_\text + p, where * ''p''total is the total pressure, * ''p''stat is the static pressure. Sound measurements Sound intensity In a sound wave, the complementary variable to sound pressure is the particle velocity. Together, they determine the sound intensity of the wave. ''Sound intensity'', denoted I and measured in W· m−2 in SI units, is defined by \mathbf I = p \mathbf v, where * ''p'' is the sound pressure, * v is the particle velocity. Acoustic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawker Siddeley HS
Hawker or Hawkers may refer to: Places *Hawker, Australian Capital Territory, a suburb of Canberra *Hawker, South Australia, a town *Division of Hawker, an Electoral Division in South Australia *Hawker Island, Princess Elizabeth Land, Antarctica *Hawker Creek, Missouri, United States In business * Hawker (trade), a vendor of food or merchandise * Hawker Aircraft, a British aircraft manufacturer * Hawkers (company), a Spanish sunglasses company Other uses * Hawker (surname) * One who practices falconry, hunting with hawks * Hawker College Hawker College is a senior secondary college in the Australian Capital Territory. It caters to students completing their final two years of secondary education, and offers a wide range of curriculum choices. Established in 1976, Hawker has a non ..., a senior secondary college in the Australian Capital Territory * Hawker (dragonfly), a family of dragonflies in North America and Europe {{DEFAULTSORT:Hawker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas DC-8
The Douglas DC-8 (sometimes McDonnell Douglas DC-8) is a long-range narrow-body airliner built by the American Douglas Aircraft Company. After losing the May 1954 US Air Force tanker competition to the Boeing KC-135, Douglas announced in July 1955 its derived jetliner project. In October 1955, Pan Am made the first order along with the competing Boeing 707, and many other airlines followed. The first DC-8 was rolled out in Long Beach Airport on April 9, 1958, and flew for the first time on May 30. FAA certification was achieved in August 1959 and the DC-8 entered service with Delta Air Lines on September 18. The six-abreast, low wing airliner was a four-engined jet aircraft with initial variants being long. The DC-8-10 was powered by Pratt & Whitney JT3C turbojets and had a MTOW, the DC-8-20 had more powerful JT4A turbojets for a MTOW. The intercontinental models had more fuel capacity and up to MTOW, powered by JT4As for the Series 30 and by Rolls-Royce Conway turbof ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pallets
A pallet (also called a skid) is a flat transport structure, which supports goods in a stable fashion while being lifted by a forklift, a pallet jack, a front loader, a jacking device, or an erect crane. A pallet is the structural foundation of a unit load, which allows handling and storage efficiencies. Goods in shipping containers are often placed on a pallet secured with strapping, stretch wrap or shrink wrap and shipped. Since its invention in the twentieth century, its use has dramatically supplanted older forms of crating like the wooden box and the wooden barrel, as it works well with modern packaging like corrugated boxes and intermodal containers commonly used for bulk shipping. In addition, pallet collars can be used to support and protect items shipped and stored on pallets. While most pallets are wooden, pallets can also be made of plastic, metal, paper, and recycled materials. Overview Containerization for transport has spurred the use of pallets because s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flight Dynamics
Flight dynamics in aviation and spacecraft, is the study of the performance, stability, and control of vehicles flying through the air or in outer space. It is concerned with how forces acting on the vehicle determine its velocity and attitude with respect to time. For a fixed-wing aircraft, its changing orientation with respect to the local air flow is represented by two critical angles, the angle of attack of the wing ("alpha") and the angle of attack of the vertical tail, known as the sideslip angle ("beta"). A sideslip angle will arise if an aircraft yaws about its centre of gravity and if the aircraft sideslips bodily, i.e. the centre of gravity moves sideways.Flightwise - Volume 2 - Aircraft Stability And Control, Chris Carpenter 1997, Airlife Publishing Ltd., , p.145 These angles are important because they are the principal source of changes in the aerodynamic forces and moments applied to the aircraft. Spacecraft flight dynamics involve three main forces: propulsive (ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Flight Control System
A conventional Fixed-wing aircraft, fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft engine controls are also considered as flight controls as they change speed. The fundamentals of aircraft controls are explained in flight dynamics (fixed-wing aircraft), flight dynamics. This article centers on the operating mechanisms of the flight controls. The basic system in use on aircraft first appeared in a readily recognizable form as early as April 1908, on Louis Blériot's Blériot VIII pioneer-era monoplane design. Cockpit controls Primary controls Generally, the primary cockpit flight controls are arranged as follows:Langewiesche, WolfgangStick and Rudder: An Explanation of the Art of Flying McGraw-Hill Professional, 1990, , . * a Yoke (aircraft), control yoke (also known as a control column), centre s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blown Flaps
Blown flaps, or jet flaps, are powered aerodynamic high-lift devices used on the wings of certain aircraft to improve their low-speed flight characteristics. They use air blown through nozzles to shape the airflow over the rear edge of the wing, directing the flow downward to increase the lift coefficient. There are a variety of methods to achieve this airflow, most of which use jet exhaust or high-pressure air bled off of a jet engine's compressor and then redirected to follow the line of trailing-edge flaps. ''Blown flaps'' may refer specifically to those systems that use internal ductwork within the wing to direct the airflow, or more broadly to systems like upper surface blowing or nozzle systems on conventional underwing engine that direct air through the flaps. Blown flaps are one solution among a broader category known as powered lift, which also includes various boundary layer control systems, systems using directed prop wash, and circulation control wings. Internal blow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-lift Device
In aircraft design and aerospace engineering, a high-lift device is a component or mechanism on an aircraft's wing that increases the amount of lift (force), lift produced by the wing. The device may be a fixed component, or a movable mechanism which is deployed when required. Common movable high-lift devices include wing Flap (aeronautics), flaps and Leading-edge slat, slats. Fixed devices include leading-edge slots, leading edge root extensions, and boundary layer control systems. Purpose The size and lifting capacity of a fixed wing is chosen as a compromise between differing requirements. For example, a larger wing will provide more lift and reduce the distance and speeds required for takeoff and landing, but will increase drag, which reduces performance during the cruising portion of flight. Modern passenger jet wing designs are optimized for speed and efficiency during the cruise portion of flight, since this is where the aircraft spends the vast majority of its flight time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STOL
A short takeoff and landing (STOL) aircraft is a conventional fixed-wing aircraft that has short runway requirements for takeoff and landing. Many STOL-designed aircraft also feature various arrangements for use on airstrips with harsh conditions (such as high altitude or ice). STOL aircraft, including those used in scheduled passenger airline operations, have also been operated from STOLport airfields which feature short runways. Design considerations Many fixed-wing STOL aircraft are bush planes, though some, like the de Havilland Canada Dash-7, are designed for use on prepared airstrips; likewise, many STOL aircraft are taildraggers, though there are exceptions like the PAC P-750 XSTOL, the Quest Kodiak, the de Havilland Canada DHC-6 Twin Otter and the Peterson 260SE. Autogyros also have STOL capability, needing a short ground roll to get airborne, but capable of a near-zero ground roll when landing. Runway length requirement is a function of the square of the minimum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
