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Aeroelastic Tailoring
Aeroelastic tailoring is defined as "the embodiment of directional stiffness into an aircraft structural design to control aeroelastic deformation, static or dynamic, in such a fashion as to affect the aerodynamic and structural performance of that aircraft in a beneficial way"Shirk, M., Hertz, T., Weisshaar, T., "Aeroelastic Tailoring – Theory, Practice, Promise", ''Journal of Aircraft'', Vol. 23, No. 1, pp. 6-18, 1986. or "passive aeroelastic control".Weisshaar, T., ''Aircraft Aeroelastic Design and Analysis'', 1995 Objectives associated with aeroelastic tailoring include weight minimization, flutter, divergence, stress, roll reversal, control effectiveness, lift, drag, skin buckling, and fatigue. History According to Shirk et al., the first record of aeroelastic tailoring is from 1949 by MunkMunk, M., "Propeller Containing Diagonally Disposed Fibrous Material," U.S. Patent 2,484,308,1111, Oct. 1949. who oriented the grain of his wooden propeller blade to create desirable def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeroelasticity
Aeroelasticity is the branch of physics and engineering studying the interactions between the inertial, elastic, and aerodynamic forces occurring while an elastic body is exposed to a fluid flow. The study of aeroelasticity may be broadly classified into two fields: ''static aeroelasticity'' dealing with the static or steady state response of an elastic body to a fluid flow; and ''dynamic aeroelasticity'' dealing with the body's dynamic (typically vibrational) response. Aircraft are prone to aeroelastic effects because they need to be lightweight and withstand large aerodynamic loads. Aircraft are designed to avoid the following aeroelastic problems: # divergence where the aerodynamic forces increase the angle of attack of a wing which further increases the force; # control reversal where control activation produces an opposite aerodynamic moment that reduces, or in extreme cases, reverses the control effectiveness; and # flutter which is the uncontained vibration that can lead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-29
The Grumman X-29 was an American experimental aircraft that tested a forward-swept wing, canard (aeronautics), canard control surfaces, and other novel aircraft technologies. The X-29 was developed by Grumman, and the two built were flown by NASA and the United States Air Force. The aerodynamics, aerodynamic instability of the X-29's airframe required the use of computerized fly-by-wire control. Composite materials were used to control the Aeroelasticity#Divergence, aeroelastic divergent twisting experienced by forward-swept wings, and to reduce weight. The aircraft first flew in 1984, and two X-29s were flight tested through 1991. Design and development Two X-29As were built by Grumman after the proposal had been chosen over a competing one involving a General Dynamics F-16 Fighting Falcon. The X-29 design made use of the forward fuselage and nose landing gear from two existing Northrop F-5, F-5A Freedom Fighter airframes (63-8372 became 82-0003 and 65-10573 became 82-0049). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Aeroelastic Wing
The X-53 Active Aeroelastic Wing (AAW) development program is a completed American research project that was undertaken jointly by the Air Force Research Laboratory (AFRL), Boeing Phantom Works and NASA's Dryden Flight Research Center, where the technology was flight tested on a modified McDonnell Douglas F/A-18 Hornet. Active Aeroelastic Wing Technology is a technology that integrates wing aerodynamics, controls, and structure to harness and control wing aeroelastic twist at high speeds and dynamic pressures. By using multiple leading and trailing edge controls like "aerodynamic tabs", subtle amounts of aeroelastic twist can be controlled to provide large amounts of wing control power, while minimizing maneuver air loads at high wing strain conditions or aerodynamic drag at low wing strain conditions. This program was the first full-scale proof of AAW technology. Development Development of the initial concept was done with wind-tunnel testing in the mid 1980s under Air Force c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing 787
The Boeing 787 Dreamliner is an American wide-body jet airliner developed and manufactured by Boeing Commercial Airplanes. After dropping its unconventional Sonic Cruiser project, Boeing announced the conventional 7E7 on January 29, 2003, which focused largely on efficiency. The program was launched on April 26, 2004, with an order for 50 aircraft from All Nippon Airways (ANA), targeting a 2008 introduction. On July 8, 2007, a prototype 787 was rolled out without major operating systems, and then the aircraft experienced multiple delays until its maiden flight on December 15, 2009. Type certification was received in August 2011 and the first 787-8 was delivered in September 2011 before entering commercial service on October 26, 2011, with ANA. At launch, Boeing targeted the 787 with 20% less fuel burn than replaced aircraft like the Boeing 767, carrying 200 to 300 passengers on point-to-point routes up to , a shift from hub-and-spoke travel. The twinjet is powered by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airbus A380
The Airbus A380 is a large wide-body airliner that was developed and produced by Airbus. It is the world's largest passenger airliner and only full-length double-deck jet airliner. Airbus studies started in 1988, and the project was announced in 1990 to challenge the dominance of the Boeing 747 in the long-haul market. The then-designated A3XX project was presented in 1994; Airbus launched the € billion ($10.7 billion) A380 programme on 19 December 2000. The first prototype was unveiled in Toulouse on 18 January 2005, with its first flight on 27 April 2005. It then obtained its type certificate from the European Aviation Safety Agency (EASA) and the US Federal Aviation Administration (FAA) on 12 December 2006. Due to difficulties with the electrical wiring, the initial production was delayed by two years and the development costs almost doubled. It was first delivered to Singapore Airlines on 15 October 2007 and entered service on 25 October. Production pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airbus A350
The Airbus A350 is a long-range, wide-body twin-engine jet airliner developed and produced by Airbus. The first A350 design proposed by Airbus in 2004, in response to the Boeing 787 Dreamliner, would have been a development of the A330 with composite wings and new engines. As market support was inadequate, in 2006, Airbus switched to a clean-sheet "XWB" (eXtra Wide Body) design, powered by two Rolls-Royce Trent XWB turbofan engines. The prototype first flew on 14 June 2013 from Toulouse in France. Type certification from the European Aviation Safety Agency (EASA) was obtained in September 2014, followed by certification from the Federal Aviation Administration (FAA) two months later. The A350 is the first Airbus aircraft largely made of carbon-fiber-reinforced polymers. It has a new fuselage designed around a nine-abreast economy cross-section, up from the eight-abreast A330/A340. It has a common type rating with the A330. The airliner has two variants: the A350-900 typi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Wing Design
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, paramotors, and hot air balloons. The human activity that surrounds aircraft is called ''aviation''. The science of aviation, including designing and building aircraft, is called ''aeronautics.'' Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others. History Flying model craft and stories of manned flight go back many centuries; however, the first manned ascent — and safe descent — in modern times took place by larger hot-air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emerging Technologies
Emerging technologies are technologies whose development, practical applications, or both are still largely unrealized. These technologies are generally new but also include older technologies finding new applications. Emerging technologies are often perceived as capable of changing the status quo. Emerging technologies are characterized by radical novelty (in application even if not in origins), relatively fast growth, coherence, prominent impact, and uncertainty and ambiguity. In other words, an emerging technology can be defined as "a radically novel and relatively fast growing technology characterised by a certain degree of coherence persisting over time and with the potential to exert a considerable impact on the socio-economic domain(s) which is observed in terms of the composition of actors, institutions and patterns of interactions among those, along with the associated knowledge production processes. Its most prominent impact, however, lies in the future and so in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
