|
Wing Sweep
A swept wing is a wing angled either backward or occasionally forward from its root rather than perpendicular to the fuselage. Swept wings have been flown since the pioneer days of aviation. Wing sweep at high speeds was first investigated in Germany as early as 1935 by Albert Betz and Adolph Busemann, finding application just before the end of the Second World War. It has the effect of delaying the shock waves and accompanying aerodynamic drag rise caused by fluid compressibility near the speed of sound, improving performance. Swept wings are therefore almost always used on jet aircraft designed to fly at these speeds. The term "swept wing" is normally used to mean "swept back", but variants include forward sweep, variable sweep wings and oblique wings in which one side sweeps forward and the other back. The delta wing is also aerodynamically a form of swept wing. Reasons for sweep There are three main reasons for sweeping a wing: 1. to arrange the center of gravity of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sukhoi Su-47 In Formation, 2005
The JSC Sukhoi Company (, ) is a Russian aircraft manufacturer headquartered in Begovoy District, Northern Administrative Okrug, Moscow, that designs both civilian and military aircraft. Sukhoi was founded in the Soviet Union by Pavel Sukhoi in 1939 as the Sukhoi Design Bureau (OKB-51, OKB, design office prefix Su), and survived the dissolution of the Soviet Union. In February 2006, the Russian government merged Sukhoi with Mikoyan, Ilyushin, Irkut (aircraft manufacturer), Irkut, Tupolev, and Yakovlev as a new company named United Aircraft Corporation.Russian Aircraft Industry Seeks Revival Through Merger ." ''The New York Times.'' February 22, 2006. History [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas DC-1
The Douglas DC-1 was the first model of the famous American DC (Douglas Commercial) commercial transport aircraft series. Although only one example of the DC-1 was produced, the design was the basis for the DC-2 and DC-3, the latter being one of the most successful aircraft in the history of aviation. Design and development Development of the DC-1 can be traced back to the 1931 crash of a TWA airliner, a Fokker F-10 trimotor in which a wing failed, likely because water had seeped between the layers of the wood laminate and dissolved the glue holding the layers together. Following the accident, the Aeronautics Branch of the U.S. Department of Commerce placed stringent restrictions on the use of wooden wings on passenger airliners.Friedman and Friedman, ''Aeroplane Monthly'' May 2001, pp. 34–40.O'Leary, ''Aeroplane Monthly'' February 2007, p. 71. Boeing developed an answer, the 247, a twin-engined all-metal monoplane with a retractable undercarriage, but their production c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas DC-8
The Douglas DC-8 (sometimes McDonnell Douglas DC-8) is an early long-range Narrow-body aircraft, narrow-body jetliner designed and produced by the American Douglas Aircraft Company. Work began in 1952 towards the United States Air Force's (USAF) requirement for a jet-powered aerial refueling, aerial refueling tanker. After losing the USAF's tanker competition to the rival Boeing KC-135 Stratotanker in May 1954, Douglas announced in June 1955 its derived jetliner project marketed to civil operators. In October 1955, Pan American World Airways, Pan Am made the first order along with the competing Boeing 707, and many other airlines soon 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. Following Federal Aviation Administration (FAA) certification in August 1959, the DC-8 entered service with Delta Air Lines on September 18. Permitting six-abreast seating, the four-engined jet aircraft, four-engined, low-wing je ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dietrich Küchemann
Dietrich Küchemann CBE FRS FRAeS (11 September 1911 – 23 February 1976) was a German aerodynamicist who made several important contributions to the advancement of high-speed flight. He spent most of his career in the UK, where he is best known for his work on Concorde. Biography Küchemann was born in Göttingen where he studied at its University of Göttingen, home of the largest German institute of aerodynamics. He was originally going to move on to pure physics research under Max Born, a friend of his father's, but lost this chance when Born and several other Jewish members of the University staff were expelled from the country by the Nazi regime. Instead Küchemann went on to join Ludwig Prandtl in aerodynamics research. He published his doctoral thesis in 1936. With the war looming, Küchemann volunteered for service in 1938, and as expected was given a non-combatant role in Signals. He held the rank of Unteroffizier from 1942 to 1945, but he saw no active se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oblique Wing
An oblique wing (also called a slewed wing) is a variable geometry wing concept. On an aircraft so equipped, the wing is designed to rotate on center pivot, so that one tip is swept forward while the opposite tip is swept aft. By changing its sweep angle in this way, drag can be reduced at high speed (with the wing swept) without sacrificing low speed performance (with the wing perpendicular). This is a variation on the classic swing-wing design, intended to simplify construction and retain the center of gravity as the sweep angle is changed. History The oldest examples of this technology are the unrealized German aircraft projects Blohm & Voss P.202 and Messerschmitt Me P.1009-01 from the year 1944, based on a Messerschmitt patent. Shortly after the conclusion of the Second World War, the German aircraft designer Dr. Richard Vogt was brought to the US during Operation Paperclip. The oblique wing concept was resurrected by the American aeronautical engineer Robert T. Jone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Empennage
The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', p. 194. Aviation Supplies & Academics, 1997. Aviation Publishers Co. Limited, ''From the Ground Up'', p. 10 (27th revised edition) The term derives from the French language verb which means " to feather an arrow". Most aircraft feature an empennage incorporating vertical and horizontal stabilising surfaces which stabilise the flight dynamics of yaw and pitch, as well as housing control surfaces. In spite of effective control surfaces, many early aircraft that lacked a stabilising empennage were virtually unflyable. Even so-called "tailless aircraft" usually have a tail fin (usually a vertical stabiliser). Heavier-than-air aircraft without any kind of empennage (such as the Northrop B-2) are rare, and generally use specially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag Divergence Mach Number
The drag-divergence Mach number (not to be confused with critical Mach number) is the Mach number at which the aerodynamic drag on an airfoil or airframe begins to increase rapidly as the Mach number continues to increase. This increase can cause the drag coefficient to rise to more than ten times its low-speed value. The value of the drag-divergence Mach number is typically greater than 0.6; therefore it is a transonic effect. The drag-divergence Mach number is usually close to, and always greater than, the critical Mach number. Generally, the drag coefficient peaks at Mach 1.0 and begins to decrease again after the transition into the supersonic regime above approximately Mach 1.2. The large increase in drag is caused by the formation of a shock wave on the upper surface of the airfoil, which can induce flow separation and adverse pressure gradients on the aft portion of the wing. This effect requires that aircraft intended to fly at supersonic speeds have a large amount of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Mach
In aerodynamics, the critical Mach number (Mcr or M*) of an aircraft is the lowest Mach number at which the airflow over some point of the aircraft reaches the speed of sound, but does not exceed it.Clancy, L.J. ''Aerodynamics'', Section 11.6 At the lower critical Mach number, airflow around the entire aircraft is subsonic. Supersonic aircraft such as the Concorde and combat aircraft also have an upper critical Mach number at which the airflow around the entire aircraft is supersonic. Aircraft flight For an aircraft in flight, the speed of the airflow around the aircraft differs considerably in places from the airspeed of the aircraft; this is due to the airflow having to speed up and slow down as it travels around the aircraft's structure. When the aircraft's airspeed reaches the critical Mach number, the speed of the airflow in some areas near the airframe reaches the speed of sound, even though the aircraft itself has an airspeed lower than Mach 1.0. This creates a weak shock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or between a fluid and a solid surface. Drag forces tend to decrease fluid velocity relative to the solid object in the fluid's path. Unlike other resistive forces, drag force depends on velocity. Drag force is proportional to the relative velocity for low-speed flow and is proportional to the velocity squared for high-speed flow. This distinction between low and high-speed flow is measured by the Reynolds number. Drag is instantaneously related to vorticity dynamics through the Josephson-Anderson relation. Examples Examples of drag include: * Net force, Net Aerodynamic force, aerodynamic or Fluid dynamics, hydrodynamic force: Drag acting opposite to the direction of movement of a solid object such as cars, aircraft, and boat hulls. * Viscou ... [...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 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swept Wing W Transonic Shock
Sweep or swept may refer to: Cleaning * Sweep, the action of using a brush to clean * Chimney sweep, a worker who clears ash and soot from chimneys * Street sweeper, a person's occupation, or a machine that cleans streets * Swept quartz, a cleaning of quartz crystal from alkali metal ions Arts, entertainment, and media * ''Sweep'' (book series), a fictional series by Cate Tiernan * Sweep (puppet), a character on the British children's television series ''The Sooty Show'' * Sweep, an ability keyword in '' Magic: The Gathering'' * Sweep-picking, a guitar technique * Sweeps period, a system of calculating viewership for television programming * ''Swept'' (album), a 1991 album by the English singer Julia Fordham * "Swept", a 1986 song by Spandau Ballet from the album ''Through the Barricades'' Detection * Bug sweeping, the common name for electronic counter surveillance * Minesweeper (ship), a small naval ship designed to engage in minesweeping * Minesweeping, the practice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jak 25
Jak or JAK may refer to: People * JAK, pen name of British cartoonist Raymond Jackson (1927–1997) * Jak Airport (c. 1955–2004), English guitarist born Jack Stafford * Jak Alnwick (born 1993), English football goalkeeper * Jak Crawford (born 2005) an American racing driver * Jak Jones (born 1993), Welsh professional snooker player * Jak Knight (1993–2022), American actor, comedian and writer * Jak Orion, stage name used by Australian musician Jack Moffitt in 2010 * José Antonio Kast (born 1966), Chilean politician also known by his initials JAK Fictional characters * Jak (''Jak and Daxter''), in ''Jak and Daxter'' video games * Jak (comics), in the UK comic book ''The Dandy'' Other uses * Ják, a village in Hungary * JAK members bank, a Swedish interest-free bank * Janus kinase, a family of intracellular, nonreceptor tyrosine kinases including ** Janus kinase 1 (JAK1) ** Janus kinase 2 (JAK2) ** Janus kinase 3 (JAK3) See also * Jack (other) * Jaks Jaks, Jåks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
