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Nike PUL 9
The Nike PUL 9 is an Argentine experimental tailless aircraft powered by a Rotax 447 engine. Design and development The PUL 9 had its origins in Argentina, the home of the German flying wing pioneer Reimar Horten since 1948. In late 1989 a collaboration between Horten and Siegfried Panek produced a design for a single seat, single pusher engine tailless aircraft. The name was an acronym of Panek UltraLight, with 9 the span in metres. Construction began near Frankfurt, Germany in January 1990 but was transferred to the Italian company Nike Aeronautica in the spring. The PUL 9 first flew on 22 June 1990. It had 30° of sweep on the leading edges of its thick (thickness/chord ratio 20%), symmetric aerofoil, wings, built using carbon fibre and Kevlar with glassfibre for the spars. The wingtips were rounded, with washout. Elevons controlled both pitch and roll; there was no vertical stabilizing surface, rudder or separate tailplane. Like some of Horten's tailless ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires. It is typically spun into ropes or fabric sheets that can be used as such, or as an ingredient in composite material components. Kevlar has many applications, ranging from bicycle tires and racing sails to bulletproof vests, all due to its high tensile strength-to-weight ratio; by this measure it is five times stronger than steel. It is also used to make modern marching drumheads that withstand high impact; and for mooring lines and other underwater applications. A similar fiber called Twaron with the same chemical structure was developed by Akzo in the 1970s; commercial production started in 1986, and Twaron is now manufactured by Teijin. History Poly-paraphenylene terephthalamide (K2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tailless Aircraft
In aeronautics, a tailless aircraft is an aircraft with no other horizontal aerodynamic surface besides its main wing. It may still have a fuselage, vertical tail fin (vertical stabilizer), and/or vertical rudder. Theoretical advantages of the tailless configuration include low parasitic drag as on the Horten H.IV soaring glider and good stealth characteristics as on the Northrop B-2 Spirit bomber. Disadvantages include a potential sensitivity to trim. Tailless aircraft have been flown since the pioneer days; the first stable aeroplane to fly was the tailless Dunne D.5, in 1910. The most successful tailless configuration has been the tailless delta, especially for combat aircraft, though the most familiar tailless delta is the Concorde airliner. NASA has used the 'tailless' description for the novel X-36 research aircraft which has a canard foreplane but no vertical fin. Aircraft configuration A tailless aircraft has no other horizontal surface besides its main wing. The aer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1990s Italian Experimental Aircraft
Year 199 (Roman numerals, CXCIX) was a common year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was sometimes known as year 952 ''Ab urbe condita''. The denomination 199 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Mesopotamia is partitioned into two Roman provinces divided by the Euphrates, Mesopotamia and Osroene. * Emperor Septimius Severus lays siege to the city-state Hatra in Central-Mesopotamia, but fails to capture the city despite breaching the walls. * Two new Roman legion, legions, Legio I Parthica, I Parthica and Legio III Parthica, III Parthica, are formed as a permanent garrison. China * Battle of Yijing: Chinese warlord Yuan Shao defeats Gongsun Zan. Korea * Geodeung of Geumgwan Gaya, Geodeung succeeds Suro of Geumgwan Gaya, as king of the Korean kingdom of Gaya co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1990s Argentine Experimental Aircraft
Year 199 ( CXCIX) was a common year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was sometimes known as year 952 ''Ab urbe condita''. The denomination 199 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Mesopotamia is partitioned into two Roman provinces divided by the Euphrates, Mesopotamia and Osroene. * Emperor Septimius Severus lays siege to the city-state Hatra in Central-Mesopotamia, but fails to capture the city despite breaching the walls. * Two new legions, I Parthica and III Parthica, are formed as a permanent garrison. China * Battle of Yijing: Chinese warlord Yuan Shao defeats Gongsun Zan. Korea * Geodeung succeeds Suro of Geumgwan Gaya, as king of the Korean kingdom of Gaya (traditional date). By topic Religion * Pope Zephyrinus succeeds Pope Vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nike PUL 10
Nike often refers to: * Nike (mythology), a Greek goddess who personifies victory * Nike, Inc., a major American producer of athletic shoes, apparel, and sports equipment Nike may also refer to: People * Nike (name), a surname and feminine given name *Nike, daughter of Shahrbaraz Arts, entertainment, and media * Nike Award, a Polish language literature prize *''Nike of Samothrace'', an ancient statue of the goddess Nike *Nike of Callimachus, an ancient statue of the goddess Nike * "Nikes" (song), by Frank Ocean from the album ''Blonde'' (2016) Military * Project Nike, a US Army missile project ** MIM-3 Nike Ajax, a solid fuel–propelled surface-to-air missile ** MIM-14 Nike-Hercules, a solid fuel–propelled surface-to-air missile ** Nike (rocket stage) ** Various US sounding rockets named after the upper stage used, including: *** Nike Apache *** Nike-Asp *** Nike-Cajun *** Nike-Deacon *** Nike Hawk *** Nike Hydac *** Nike Iroquois *** Nike Javelin *** Nike Malemute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drum Brakes
A drum brake is a brake that uses friction caused by a set of shoes or pads that press outward against a rotating cylinder-shaped part called a brake drum. The term ''drum brake'' usually means a brake in which shoes press on the inner surface of the drum. When shoes press on the outside of the drum, it is usually called a '' clasp brake''. Where the drum is pinched between two shoes, similar to a conventional disc brake, it is sometimes called a ''pinch drum brake'', though such brakes are relatively rare. A related type called a band brake uses a flexible belt or "band" wrapping around the outside of a drum. History The modern automobile drum brake was first used in a car made by Maybach in 1900, although the principle was only later patented in 1902 by Louis Renault. He used woven asbestos lining for the drum brake lining, as no alternative dissipated heat like the asbestos lining, though Maybach had used a less sophisticated drum brake. In the first drum brakes, levers a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Absorbers
A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most shock absorbers are a form of dashpot (a damper which resists motion via viscous friction). Description Pneumatic and hydraulic shock absorbers are used in conjunction with cushions and springs. An automobile shock absorber contains spring-loaded check valves and orifices to control the flow of oil through an internal piston (see below). One design consideration, when designing or choosing a shock absorber, is where that energy will go. In most shock absorbers, energy is converted to heat inside the viscous fluid. In hydraulic cylinders, the hydraulic fluid heats up, while in air cylinders, the hot air is usually exhausted to the atmosphere. In other types of shock absorbers, such as electromagnetic types, the dissipated energy can be s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricycle Gear
Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', arranged in a tricycle fashion. The tricycle arrangement has a single nose wheel in the front, and two or more main wheels slightly aft of the center of gravity. Tricycle gear aircraft are the easiest for takeoff, landing and taxiing, and consequently the configuration is the most widely used on aircraft.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 524. Aviation Supplies & Academics, 1997. Aviation Publishers Co. Limited, ''From the Ground Up'', page 11 (27th revised edition) History Several early aircraft had primitive tricycle gear, notably very early Antoinette planes and the Curtiss Pushers of the pre-World War I Pioneer Era of aviation. Waldo Waterman's 1929 tailless '' Whatsit'' was one of the first to have a steerable nose wheel. In 1956, Cessna introduced sprung-steel tricycle landing gear on the Cessna 172. Their marketing department described this as "Land-O-Matic" t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elevons
Elevons or tailerons are aircraft control surfaces that combine the functions of the elevator (used for pitch control) and the aileron (used for roll control), hence the name. They are frequently used on tailless aircraft such as flying wings. An elevon that is not part of the main wing, but instead is a separate tail surface, is a stabilator (but stabilators are also used for pitch control only, with no roll function, as on the Piper Cherokee series of aircraft). Elevons are installed on each side of the aircraft at the trailing edge of the wing. When moved in the same direction (up or down) they will cause a pitching force (nose up or nose down) to be applied to the airframe. When moved differentially, (one up, one down) they will cause a rolling force to be applied. These forces may be applied simultaneously by appropriate positioning of the elevons e.g. one wing's elevons completely down and the other wing's elevons partly down. An aircraft with elevons is controlled as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washout (aviation)
Washout is a characteristic of aircraft wing design which deliberately reduces the lift distribution across the span of an aircraft’s wing. The wing is designed so that the 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 speed the wing root stalls before the wing tips, providing the aircraft with continued aileron control and some resistance to 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 with a slight twist, reducing the 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 structural washout, to distinguish it from aerodynamic washout. Wingtip stall is unlikely to occur symmetrically, especially if the aircraft is maneuvering. As an air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
