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Sabre Dance (pitch-up)
In aerodynamics, pitch-up is an uncommanded nose-upwards rotation of an aircraft. It is an undesirable characteristic that has been observed mostly in experimental swept-wing aircraft at high subsonic Mach numbers or high angle of attack. History Pitch-up problems were first noticed on high-speed test aircraft with swept wings. It was a common problem on the Douglas Skyrocket, which was used extensively to test the problem. Before the pitch-up phenomenon was well understood, it plagued all early swept-wing aircraft. In the F-100 Super Sabre it even got its own name, the Sabre dance. In aircraft with high-mounted tailplanes, like the F-101 Voodoo, recovery was especially difficult because the tailplane was placed directly in the wing wake during the pitch-up, causing deep stall (although the T-tail was meant to prevent pitch-up from starting in the first place). Deployment of the braking parachute and a considerable height above the ground were essential for a chance at recovery. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messerschmitt Me 163B USAF
Messerschmitt AG () was a German Aktiengesellschaft, share-ownership limited, Aerospace manufacturer, aircraft manufacturing corporation named after its chief designer Willy Messerschmitt from 1938 in aviation#July, mid-July 1938 onwards, and known primarily for its World War II fighter aircraft, in particular the Messerschmitt Bf 109, Bf 109 and Messerschmitt Me 262, Me 262. The company survived in the post-war era, undergoing a number of mergers and changing its name from Messerschmitt to Messerschmitt-Bölkow-Blohm before being bought by Deutsche Aerospace (DASA, now part of Airbus) in 1989. History Background In February 1916, the south German engineering company MAN SE, MAN AG and several banks purchased the unprofitable aircraft builder Otto-Flugzeugwerke, starting a new company, ''Bayerische Flugzeugwerke AG'' (abbreviated ''B.F.W.'', and meaning approximately "Bavarian Aircraft Factory"). The articles of association were drawn up on 19 and 20 February, and completed on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Tunnel
A wind tunnel is "an apparatus for producing a controlled stream of air for conducting aerodynamic experiments". The experiment is conducted in the test section of the wind tunnel and a complete tunnel configuration includes air ducting to and from the test section and a device for keeping the air in motion, such as a fan. Wind tunnel uses include assessing the effects of air on an aircraft in flight or a ground vehicle moving on land, and measuring the effect of wind on Building, buildings and bridges. Wind tunnel test sections range in size from less than a foot across, to over , and with air speeds from a light breeze to hypersonic. The earliest wind tunnels were invented towards the end of the 19th century, in the early days of aeronautical research, as part of the effort to develop heavier-than-air flying machines. The wind tunnel reversed the usual situation. Instead of the air standing still and an aircraft moving, an object would be held still and the air moved around it. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XF-91 Thunderceptor
The Republic XF-91 Thunderceptor (originally designated XP-91) is a mixed-propulsion prototype interceptor aircraft, developed by Republic Aviation. The aircraft would use a jet engine for most flight, and a cluster of four small rocket engines for added thrust during climb and interception. The design was largely obsolete by the time it was completed due to the rapidly increasing performance of contemporary jet engines, and only two prototypes were built. One of these was the first American fighter to exceed Mach (speed), Mach 1 in level flight. A unique feature of the Thunderceptor was its unusual inverse tapered wing, in which the Chord (aeronautics), chord length increased along the wing span from the root to the tip, the opposite of conventional swept wing designs. This was an attempt to address the problem of pitch-up, a potentially deadly phenomenon that plagued early high-speed models. The Thunderceptor's design meant the entire wing Stall (flight), stalled smoothly, more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aileron
An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around the aircraft's longitudinal axis), which normally results in a change in flight path due to the tilting of the lift vector. Movement around this axis is called rolling or banking. Considerable controversy exists over credit for the invention of the aileron. The Wright brothers and Glenn Curtiss fought a years-long legal battle over the Wright patent of 1906, which described a method of wing-warping to achieve lateral control. The brothers prevailed in several court decisions which found that Curtiss's use of ailerons violated the Wright patent. Ultimately, the First World War compelled the U.S. Government to legislate a legal resolution. A much earlier aileron concept was patented in 1868 by British scientist Matthew Piers Watt Boul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washout (aviation)
Washout is a characteristic of aircraft wing design which deliberately changes the Lift (force), lift distribution across the Wingspan, span of an aircraft’s wing. The wing is designed so that the angle of incidence (aerodynamics), angle of incidence is greater at the wing roots and decreases across the span, becoming lowest at the wing tip. This is usually to ensure that at Stall (flight), stall speed the wing root stalls before the wing tips, providing the aircraft with continued aileron control and some resistance to Spin (flight), spinning. Washout may also be used to modify the spanwise lift distribution to reduce lift-induced drag. Design considerations Washout is commonly achieved by designing the Wing#Artificial Wings, wing with a slight Wing twist, twist, reducing the angle of incidence (aerodynamics), angle of incidence from root to tip, and therefore causing a lower angle of attack at the tips than at the roots. This feature is sometimes referred to as geometrica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leading Edge Slats
A slat is an aerodynamic surface on the leading edge of the wing of a fixed-wing aircraft. When retracted, the slat lies flush with the rest of the wing. A slat is deployed by sliding forward, opening a slot between the wing and the slat. Air from below the slat flows through the slot and replaces the boundary layer that has travelled at high speed around the leading edge of the slat, losing a significant amount of its kinetic energy due to skin friction drag. When deployed, slats allow the wings to operate at a higher angle of attack before stalling. With slats deployed an aircraft can fly at slower speeds, allowing it to take off and land in shorter distances. They are used during takeoff and landing and while performing low-speed maneuvers which may take the aircraft close to a stall. Slats are retracted in normal flight to minimize drag. Slats are high-lift devices typically used on aircraft intended to operate within a wide range of speeds. Trailing-edge flap systems runn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wing Fence
A wing is a type of fin that produces both lift and drag while moving through air. Wings are defined by two shape characteristics, an airfoil section and a planform. Wing efficiency is expressed as lift-to-drag ratio, which compares the benefit of lift with the air resistance of a given wing shape, as it flies. Aerodynamics is the study of wing performance in air. Equivalent foils that move through water are found on hydrofoil power vessels and foiling sailboats that lift out of the water at speed and on submarines that use diving planes to point the boat upwards or downwards, while running submerged. Hydrodynamics is the study of foil performance in water. Etymology and usage The word "wing" from the Old Norse ''vængr'' for many centuries referred mainly to the foremost limbs of birds (in addition to the architectural aisle). But in recent centuries the word's meaning has extended to include lift producing appendages of insects, bats, pterosaurs, boomerangs, some sai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podded Engine
A podded engine is a jet engine that has been built up and integrated in its nacelle. This may be done in a podding facility as part of an aircraft assembly process. The nacelle contains the engine, engine mounts and parts which are required to run the engine in the aircraft, known as the EBU (Engine Build Up). The nacelle consists of an inlet, an exhaust nozzle and a cowling which opens for access to the engine accessories and external tubing. The exhaust nozzle may include a thrust reverser. The podded engine is a complete powerplant, or propulsion system, and is usually attached below the wing on large aircraft like commercial airliners or to the rear fuselage on smaller aircraft such as business jets. Engine Build Up The EBU components connect the engine systems with the aircraft systems. Engine build up includes installation of an engine starter, hydraulic pumps, electrical generators and firewire and components which connect the engine to the aircraft. They include the fol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing B-47 Stratojet
The Boeing B-47 Stratojet (Boeing company designation Model 450) is a retired American long- range, six-engined, turbojet-powered strategic bomber designed to fly at high subsonic speed and at high altitude to avoid enemy interceptor aircraft. The primary mission of the B-47 was as a nuclear bomber capable of striking targets within the Soviet Union. Development of the B-47 can be traced back to a requirement expressed by the United States Army Air Forces (USAAF) in 1943 for a reconnaissance bomber that harnessed newly-developed jet propulsion. Another key innovation adopted during the development process was the swept wing, drawing upon captured German research. With its engines carried in nacelles underneath the wing, the B-47 represented a major innovation in post–World War II combat jet design, and contributed to the development of modern jet airliners. In April 1946, the USAAF ordered two prototypes, designated "XB-47. On 17 December 1947, the first prototype perfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vortex Generator
A vortex generator (VG) is an aerodynamic device, consisting of a small wikt:vane, vane usually attached to a lifting surface (or airfoil, such as an aircraft, aircraft wing) or a rotor blade of a wind turbine.Wind Turbine Vortex Generators UpWind Solutions. VGs may also be attached to some part of an aerodynamic vehicle such as an aircraft fuselage or a car. When the airfoil or the body is in motion relative to the air, the VG creates a vortex,Peppler, I.L.: ''From The Ground Up'', page 23. Aviation Publishers Co. Limited, Ottawa Ontario, Twenty Seventh Revised Edition, 1996. which, by removing some part of the slow-moving boundary layer in contact with the airfoil surface, delays local flow separation and Sta ... [...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 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 flaps and 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. High-lift devices compensate for this design t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian CF-18
Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''Canadian''. Canada is a multilingual and multicultural society home to people of groups of many different ethnic, religious, and national origins, with the majority of the population made up of Old World immigrants and their descendants. Following the initial period of French and then the much larger British colonization, different waves (or peaks) of immigration and settlement of non-indigenous peoples took place over the course of nearly two centuries and continue today. Elements of Indigenous, French, British, and more recent immigrant customs, languages, and religions have combined to form the culture of Canada, and thus a Canadian identity and Canadian values. Canada has also been strongly influenced by its linguistic, geographic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
