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21-446: (Redirected from A-12 ) A12 , A.12 or A-12 may refer to: Aviation [ edit ] A-12 Shrike , a World War 2–era American attack aircraft Abrial A-12 Bagoas , a French experimental glider of the 1930s Aero A.12 , a Czechoslovak light bomber built after World War I Lockheed A-12 , codenamed Oxcart , a high-altitude, high-speed reconnaissance aircraft, manufactured for

42-553: A 440 engine and special transmission and differential features. [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=A12&oldid=1248348862 " Category : Letter–number combination disambiguation pages Hidden categories: Short description

63-521: A British A-class submarine of the Royal Navy Matilda II (tank) , built to General Staff specification A12, a British tank of World War 2 Science and technology [ edit ] A12 Authentication , a CHAP-based mechanism used by a CDMA2000 Access Network to authenticate a 1xEV-DO Access Terminal ARM Cortex-A12 , a 32-bit multicore processor Apple A12 , a 7-nanometer 64-bit ARM SoC ATC code A12 Mineral supplements ,

84-404: A V- strut on each side, their apexes meeting at a faired triangular central support structure. It had control surfaces on the wings which may have operated as elevons and trapezoidal rudders mounted on triangular fins at the wing tips. The pilot's unenclosed seat was immediately in front of the central support structure, at the centre of the wing, with his feet on a rudder bar ahead of

105-763: A bus route in Washington, USA A12 scale , musical tuning based on the 4:7:10 triad One of the Encyclopaedia of Chess Openings codes for the English Opening Unite the Right rally , referred to as "A12" locally, a white supremacist rally in Charlottesville, Virginia, which took place on August 12, 2017 X Æ A-12, the son of Elon Musk A highly desirable performance option for the 1969 Plymouth Road Runner and Dodge Super Bee with

126-403: A constant-chord wing of chord c and span b , the aspect ratio is given by: If the wing is swept, c is measured parallel to the direction of forward flight. For most wings the length of the chord is not a constant but varies along the wing, so the aspect ratio AR is defined as the square of the wingspan b divided by the wing area S . In symbols, For such a wing with varying chord,

147-428: A high-aspect-ratio wing. However, as the flow becomes transonic and then supersonic, the shock wave first generated along the wing's upper surface causes wave drag on the aircraft, and this drag is proportional to the span of the wing. Thus a long span, valuable at low speeds, causes excessive drag at transonic and supersonic speeds. By varying the sweep the wing can be optimised for the current flight speed. However,

168-434: A large cylinder of air, and a small wingspan affects a small cylinder of air. A small air cylinder must be pushed down with a greater power (energy change per unit time) than a large cylinder in order to produce an equal upward force (momentum change per unit time). This is because giving the same momentum change to a smaller mass of air requires giving it a greater velocity change, and a much greater energy change because energy

189-478: A long, narrow wing with a high aspect ratio has aerodynamic advantages like better lift-to-drag-ratio (see also details below), there are several reasons why not all aircraft have high aspect-ratio wings: Aircraft which approach or exceed the speed of sound sometimes incorporate variable-sweep wings . These wings give a high aspect ratio when unswept and a low aspect ratio at maximum sweep. In subsonic flow, steeply swept and narrow wings are inefficient compared to

210-614: A subgroup of the Anatomical Therapeutic Chemical Classification System British NVC community A12 (Potamogeton pectinatus community) , a British Isles plant community A Rhodopsin-like receptors subfamily Samsung Galaxy A12 , an Android phone Other uses [ edit ] A12 road , in several countries Fiat A.12 , a 1916 Italian, 6–cylinder, liquid-cooled in-line engine LSWR A12 class , an 1887 British steam locomotive model Route A12 (WMATA) ,

231-594: Is different from Wikidata All article disambiguation pages All disambiguation pages Abrial A-12 Bagoas The Abrial A-12 was unusual in having a very low aspect ratio wing, even by the standards of its time. Other tailless gliders of the 1920s, notably the Lippisch Storch series had aspect ratios of about 8, compared with the 4.75 of the Abrial. Further, where the Storchs had swept wings

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252-416: Is proportional to the square of the velocity while momentum is only linearly proportional to the velocity. The aft-leaning component of this change in velocity is proportional to the induced drag , which is the force needed to take up that power at that airspeed. It is important to keep in mind that this is a drastic oversimplification, and an airplane wing affects a very large area around itself. Although

273-436: The aspect ratio of a wing is the ratio of its span to its mean chord . It is equal to the square of the wingspan divided by the wing area. Thus, a long, narrow wing has a high aspect ratio, whereas a short, wide wing has a low aspect ratio. Aspect ratio and other features of the planform are often used to predict the aerodynamic efficiency of a wing because the lift-to-drag ratio increases with aspect ratio, improving

294-415: The fuel economy in powered airplanes and the gliding angle of sailplanes. The aspect ratio AR {\displaystyle {\text{AR}}} is the ratio of the square of the wingspan b {\displaystyle b} to the projected wing area S {\displaystyle S} , which is equal to the ratio of the wingspan b {\displaystyle b} to

315-625: The leading edge . The Abrial landed on a skid, with little wheels under the wing tips. Abrial named the A-12 Bagoas , after the Persian Vizier and poisoner. Its first flights were made during the first week of July 1932. It presented so many technical problems that he abandoned development later that year. Data from Les Ailes July 1932 General characteristics Aircraft of comparable role, configuration, and era Aspect ratio (aeronautics) In aeronautics ,

336-467: The standard mean chord SMC is defined as The performance of aspect ratio AR related to the lift-to-drag-ratio and wingtip vortices is illustrated in the formula used to calculate the drag coefficient of an aircraft C d {\displaystyle C_{d}\;} where The wetted aspect ratio considers the whole wetted surface area of the airframe, S w {\displaystyle S_{w}} , rather than just

357-419: The Abrial's was rectangular in plan. After encouraging tests of models in the wind tunnel at St Cyr , Abrial built a full-sized version. The Abrial's wings had the designer's own reflexed camber aerofoil . Such aerofoils are useful for tailless aircraft, because the pitching moment about the aerodynamic centre of the wing can be zero. The wings were mounted with strong dihedral and braced from above by

378-701: The CIA McDonnell Douglas A-12 Avenger II , an early attempt by the United States to develop stealth aircraft, cancelled due to cost overruns Military [ edit ] Aggregate 12 , a German rocket design in World War II that was never constructed Brazilian aircraft carrier  São Paulo  (A12) , a French-built aircraft carrier in use by the Brazilian Navy HMS ; A12 ,

399-491: The extra weight and complexity of a moveable wing mean that such a system is not included in many designs. The aspect ratios of birds' and bats' wings vary considerably. Birds that fly long distances or spend long periods soaring such as albatrosses and eagles often have wings of high aspect ratio. By contrast, birds which require good maneuverability, such as the Eurasian sparrowhawk , have wings of low aspect ratio. For

420-430: The standard mean chord SMC {\displaystyle {\text{SMC}}} : AR ≡ b 2 S = b SMC {\displaystyle {\text{AR}}\equiv {\frac {b^{2}}{S}}={\frac {b}{\text{SMC}}}} As a useful simplification, an airplane in flight can be imagined to affect a cylinder of air with a diameter equal to the wingspan. A large wingspan affects

441-511: The wing. It is a better measure of the aerodynamic efficiency of an aircraft than the wing aspect ratio . It is defined as: where b {\displaystyle b} is span and S w {\displaystyle S_{w}} is the wetted surface . Illustrative examples are provided by the Boeing B-47 and Avro Vulcan . Both aircraft have very similar performance although they are radically different. The B-47 has

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