Akaflieg Darmstadt D-36
The Akaflieg Darmstadt D-36 Circe is a single seat, high performance sailplane designed and built in Germany in the mid-1960s, one of the early "glass ships". It was the winner at the German National Championships in 1964 and came second in the World Championships the following year. Design and development The Akademische Fliegergruppe of the Technical University of Darmstadt ( Akaflieg Darmstadt) was first formed in 1921. It was, and is, a group of aeronautical students who design and construct aircraft as part of their studies and with the help and encouragement of their University. Design work on the Circe began in 1962-3 by a team of students, Wolf Lemke (responsible for the wing), Gerhard Waibel (fuselage and tail) and Heiko Friess (airbrakes). They were later joined by the younger Klaus Holighaus. Professor Franz Wortmann designed a new airfoil for the Circe. Construction began in 1963 and the aircraft flew for the first time, piloted by Wolf Lemke, on 28 March 1964 at ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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WikiProject Aircraft
A WikiProject, or Wikiproject, is a Wikimedia movement affinity group for contributors with shared goals. WikiProjects are prevalent within the largest wiki, Wikipedia, and exist to varying degrees within sister projects such as Wiktionary, Wikiquote, Wikidata, and Wikisource. They also exist in different languages, and translation of articles is a form of their collaboration. During the COVID-19 pandemic, CBS News noted the role of Wikipedia's WikiProject Medicine in maintaining the accuracy of articles related to the disease. Another WikiProject that has drawn attention is WikiProject Women Scientists, which was profiled by '' Smithsonian'' for its efforts to improve coverage of women scientists which the profile noted had "helped increase the number of female scientists on Wikipedia from around 1,600 to over 5,000". On Wikipedia Some Wikipedia WikiProjects are substantial enough to engage in cooperative activities with outside organizations relevant to the field at issue. For e ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Stall (flight)
In fluid dynamics, a stall is a reduction in the lift coefficient generated by a foil as angle of attack increases.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', p. 486. Aviation Supplies & Academics, 1997. This occurs when the critical angle of attack of the foil is exceeded. The critical angle of attack is typically about 15°, but it may vary significantly depending on the fluid, foil, and Reynolds number. Stalls in fixed-wing flight are often experienced as a sudden reduction in lift as the pilot increases the wing's angle of attack and exceeds its critical angle of attack (which may be due to slowing down below stall speed in level flight). A stall does not mean that the engine(s) have stopped working, or that the aircraft has stopped moving—the effect is the same even in an unpowered glider aircraft. Vectored thrust in aircraft is used to maintain altitude or controlled flight with wings stalled by replacing lost wing lift with engine or propeller t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Aeroelastic Flutter
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]   |
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Monowheel
A monowheel, or uniwheel, is a one-wheeled single-track vehicle similar to a unicycle. Hand-cranked and pedal-powered monowheels were patented and built in the late 19th century; most built in the 20th and 21st century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles. The world speed record for a motorized monowheel is 98.464 km/h (61.18 mph). Stability Similar to bicycles, monowheels are stable in the direction of travel, but have limited horizontal stability. This is in contrast to unicycles which are unstable in both directions. Monowheels have also been found to have a lower speed required for stability when compared to unicycles. A monowheel remains upright due to gyroscopic effects, but its lack of stability makes it highly dependent on forward momentum and the balance of the rider, who must maintain stability while steering. Over the history of the monow ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Canopy (aircraft)
An aircraft canopy is the transparent enclosure over the cockpit of some types of aircraft. An aircraft canopy provides a controlled and sometimes pressurized environment for the aircraft's occupants, and allows for a greater field of view over a traditional flight deck. A canopy's shape is a compromise designed to minimize aerodynamic drag, while maximizing visibility for pilots and other crewmembers. History Very early aircraft had no canopies. The pilots were exposed to the wind and weather, although most flying was done in good weather. Through World War I most aircraft had no canopy, although they often had a small windshield to deflect the prop wash and wind from hitting the pilot in the face. In the 1920s and 1930s, the increasing speed and altitude of airplanes necessitated a fully enclosed cockpit and canopies became more common. Early canopies were made of numerous pieces of flat glass held in position by a frame and muntins. The muntins reduced visibility, which w ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cockpit
A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a Pilot in command, pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls that enable the pilot to fly the aircraft. In most airliners, a door separates the cockpit from the aircraft cabin. After the September 11 attacks, September 11, 2001 attacks, all major airlines Airport_security_repercussions_due_to_the_September_11_attacks#Improved_security_on_aircraft, fortified their cockpits against access by aircraft hijacking, hijackers. Etymology The word cockpit seems to have been cockpit (sailing), used as a nautical term in the 17th century, without reference to cock fighting. It referred to an area in the rear of a ship where the cockswain's station was located, the cockswain being the pilot of a smaller "boat" that could be dispatched from the ship to board another ship or to bring people ashore. The ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Leading Edge
The leading edge of an airfoil surface such as a wing is its foremost edge and is therefore the part which first meets the oncoming air.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, 1997. Characteristics Sweep Seen in plan the leading edge may be straight, curved, kinked or a combination of these. A straight leading edge may be swept or unswept, while curves or kinks always mean that part of the leading edge is swept. On a swept wing the sweep angle may differ from that of the wing, as wing sweep is conventionally measured at the airfoil 25% chord line. However on a delta wing the leading edge sweep defines the wing sweep. Radius and stagnation point A rounded leading edge helps to maintain a smooth airflow at varying angles of incidence to the airflow. Most subsonic airfoils therefore have a rounded leading edge. The degree of rounding is characterised by the profile radius at that point. The airflow divides to ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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T-tail
A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane is mounted to the fuselage at the base of the fin. Advantages T-tails were common in early jet aircraft. Designers were worried that an engine failure would otherwise damage the horizontal tail. The T-tail is very common on aircraft with engines mounted in nacelles on a high-winged aircraft or on aircraft with the engines mounted on the rear of the fuselage, as it keeps the tail clear of the jet exhaust. Rear-mounting the engines keeps the wings clean and improves short-field performance. This was necessary in early jet aircraft with less powerful engines. T-tail aircraft can have better short-field performance, such as on the Avro RJ-85. The disturbed airflow over a lower stabilizer can make control more difficult at lower speeds. Dur ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Trailing Edge
The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. Essential flight control surfaces are attached here to control the direction of the departing air flow, and exert a controlling force on the aircraft. Such control surfaces include ailerons on the wings for roll control, elevators on the tailplane controlling pitch, and the rudder on the fin controlling yaw. Elevators and ailerons may be combined as elevons on tailless aircraft. The shape of the trailing edge is of prime importance in the aerodynamic function of any aerodynamic surface. George Batchelor has written about: :“ ... the remarkable controlling influence exerted by the sharp trailing edge of an aerofoil on the circulation.”Batchelor, G. K. (1967), ''An Introduction to Fluid Dynamics'', p.438, Cambridge University Press. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Rudder
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane. A rudder operates by redirecting the fluid past the hull (watercraft), hull or fuselage, thus imparting a turning or yaw (rotation), yawing motion to the craft. In basic form, a rudder is a flat plane or sheet of material attached with hinges to the craft's stern, tail, or after end. Often rudders are shaped so as to minimize Drag (physics), hydrodynamic or aerodynamic drag. On simple watercraft, a tiller—essentially, a stick or pole acting as a lever arm—may be attached to the top of the rudder to allow it to be turned by a helmsman. In larger vessels, cables, pushrods, or hydraulics may be used to link rudders to steering wheels. In typical air ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Shoulder Wing
A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplane (aeronautics), multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing configuration and is the simplest to build. However, during the early years of flight, these advantages were offset by its greater weight and lower manoeuvrability, making it relatively rare until the 1930s. Since then, the monoplane has been the most common form for a fixed-wing aircraft. Characteristics Support and weight The inherent efficiency of the monoplane is best achieved in the cantilever wing, which carries all structural forces internally. However, to fly at practical speeds the wing must be made thin, which requires a heavy structure to make it strong and stiff enough. External Bracing (aeronautics), bracing can be used to improve structural efficiency, reducing weight and cost. For a wing of a given size, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Parallel Rulers
Parallel rulers are a drafting instrument used by navigators to draw parallel lines on charts. The tool consists of two straight edges joined by two arms which allow them to move closer or further away while always remaining parallel to each other. History The parallel ruler was invented in about 1584 by Fabrizio Mordente, but it was not in common use until the 18th century. In the 19th century a retired sea captain, Captain William Andrew Field improved the design by adding a protractor-style scale to the upper edge of one rule, and compass points to the opposing edge, which made reading bearings easier. Examples exist of boxwood, ivory or ebony, usually with brass hinges. The instrument usually had two links, but longer models sometimes had three, and sometimes the links were scissored. Another variation is the "roller" model which included a cylindrical roller for ease of use. See also * Cras protractor * Technical drawing tools Drafting tools may be used for measurement ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |