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Ground Effect (aerodynamics)
For fixed-wing aircraft, ground effect is the reduced aerodynamic drag that an aircraft's wings generate when they are close to a fixed surface.. During takeoff, ground effect can cause the aircraft to "float" while below the recommended climb speed. The pilot can then fly just above the runway while the aircraft accelerates in ground effect until a safe climb speed is reached.. For rotorcraft, ground effect results in less drag on the rotor during hovering close to the ground. At high weights this sometimes allows the rotorcraft to lift off while stationary in ground effect but does not allow it to transition to flight out of ground effect. Helicopter pilots are provided with performance charts which show the limitations for hovering their helicopter in ground effect (IGE) and out of ground effect (OGE). The charts show the added lift benefit produced by ground effect. For fan and jet-powered vertical take-off and landing (VTOL) aircraft, ground effect when hovering can cause su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fixed-wing Aircraft
A fixed-wing aircraft is a heavier-than-air aircraft, such as an airplane, which is capable of flight using aerodynamic lift. Fixed-wing aircraft are distinct from rotary-wing aircraft (in which a rotor mounted on a spinning shaft generates lift), and ornithopters (in which the wings oscillate to generate lift). The wings of a fixed-wing aircraft are not necessarily rigid; kites, hang gliders, variable-sweep wing aircraft, and airplanes that use wing morphing are all classified as fixed wing. Gliding fixed-wing aircraft, including free-flying gliders and tethered kites, can use moving air to gain altitude. Powered fixed-wing aircraft (airplanes) that gain forward thrust from an engine include powered paragliders, powered hang gliders and ground effect vehicles. Most fixed-wing aircraft are operated by a pilot, but some are unmanned or controlled remotely or are completely autonomous (no remote pilot). History Kites Kites were used approximately 2,800 years ago ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell X-14
The Bell X-14 (Bell Type 68) is an experimental VTOL aircraft flown in the United States in the 1950s. The main objective of the project was to demonstrate vectored thrust horizontal and vertical takeoff, hover, transition to forward flight, and vertical landing. Design and development Bell constructed the X-14 as an open- cockpit, all-metal (duralumin) monoplane for the USAF. It was powered by two Armstrong Siddeley Viper turbojet engines equipped with thrust deflectors sited at the aircraft's centre of gravity. The engines are fixed in position; transition from vertical to horizontal flight is achieved with a system of movable vanes that control the direction of engine thrust. Top speed was with a service ceiling of . The X-14 was designed using existing parts from two Beechcraft aircraft: wings, ailerons, and landing gear of a Beech Bonanza and the tailcone and empennage of a Beech T-34 Mentor. Operational history The X-14 first flew on 19 February 1957 as a vertica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defence Science And Technology Organisation
Defense or defence may refer to: Tactical, martial, and political acts or groups * Defense (military), forces primarily intended for warfare * Civil defense, the organizing of civilians to deal with emergencies or enemy attacks * Defense industry, industry which manufactures and sells weapons and military technology * Self-defense, the use of force to defend oneself * Haganah (Hebrew for "The Defence"), a paramilitary organization in British Palestine * National security, security of a nation state, its citizens, economy, and institutions, as a duty of government ** Defence diplomacy, pursuit of foreign policy objectives through the peaceful employment of defence resources ** Ministry of defence or department of defense, a part of government which regulates the armed forces ** Defence minister, a cabinet position in charge of a ministry of defense * International security, measures taken by states and international organizations to ensure mutual survival and safety Sports * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Melbourne Institute Of Technology
The Royal Melbourne Institute of Technology (abbreviated as RMIT University) is a public research university located in the city of Melbourne in Victoria, Australia., section 4(b) Established in 1887 by Francis Ormond, it is the seventh-oldest institution of higher education in Australia, a founding member of the Australian Technology Network (ATN), and a member of Universities Australia (UA). RMIT began as a night school offering classes in art, science and technology in response to the Industrial Revolution in Australia. It was a private college for more than a hundred years before merging with the Phillip Institute of Technology to become a public university in 1992. It has an enrolment of around 95,000 higher and vocational education students. With an annual revenue of around A$1.5 billion. It is ranked 15th in the World for art and design subjects in the QS World University Rankings. The main campus of RMIT is situated on the northern edge of the historic Hoddl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawrence Wackett
Sir Lawrence James Wackett (2 January 1896 – 18 March 1982) is widely regarded as "father of the Australian aircraft industry". He has been described as "one of the towering figures in the history of Australian aviation covering, as he did, virtually all aspects of activities: pilot, designer of airframes and engines, entrepreneur and manager". He was knighted for his services to aviation and was a winner of the Oswald Watt Gold Medal. He was also a keen angling, angler and wrote two books on the subject. Early years, war service and education Wackett was born in Townsville, Queensland, on 2 January 1896. He joined the Australian Army and graduated from the Royal Military College, Duntroon, then with the rank of lieutenant joined No. 1 Squadron RAAF, No. 1 Squadron of the Australian Flying Corps (AFC) which had formed at RAAF Williams, Point Cook the day before his 20th birthday. He was one of twelve pilots that went to Egypt with the Squadron to operate in support of the Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vortex Ring
A vortex ring, also called a toroidal vortex, is a torus-shaped vortex in a fluid; that is, a region where the fluid mostly spins around an imaginary axis line that forms a closed loop. The dominant flow in a vortex ring is said to be toroidal, more precisely poloidal. Vortex rings are plentiful in turbulent flows of liquids and gases, but are rarely noticed unless the motion of the fluid is revealed by suspended particles—as in the smoke rings which are often produced intentionally or accidentally by smokers. Fiery vortex rings are also a commonly produced trick by fire eaters. Visible vortex rings can also be formed by the firing of certain artillery, in mushroom clouds, in microbursts, and rarely in volcanic eruptions. A vortex ring usually tends to move in a direction that is perpendicular to the plane of the ring and such that the inner edge of the ring moves faster forward than the outer edge. Within a stationary body of fluid, a vortex ring can travel for relative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hovercraft
A hovercraft (: hovercraft), also known as an air-cushion vehicle or ACV, is an amphibious craft capable of travelling over land, water, mud, ice, and various other surfaces. Hovercraft use blowers to produce a large volume of air below the Hull (watercraft), hull, or air cushion, that is slightly above atmospheric pressure. The pressure difference between the higher-pressure air below the hull and lower pressure ambient air above it produces lift, which causes the hull to float above the running surface. For stability reasons, the air is typically blown through slots or holes around the outside of a disk- or oval-shaped platform, giving most hovercraft a characteristic rounded-rectangle shape. The first practical design for hovercraft was derived from a British invention in the 1950s. They are now used throughout the world as specialised transports in disaster relief, coastguard, military and survey applications, as well as for sport or passenger service. Very large version ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Effect (cars)
In car design, ground effect is a series of effects which have been exploited in automotive aerodynamics to create downforce, particularly in racing cars. This has been the successor to the earlier dominant aerodynamic focus on streamlining. The international Formula One series and American racing IndyCars employ ground effects in their engineering and designs. Similarly, they are also employed in other racing series to some extent; however, across Europe, many series employ regulations (or complete bans) to limit its effectiveness on safety grounds. Theory In racing cars, a designer's aim is for increased downforce and grip to achieve higher cornering speeds. A substantial amount of downforce is available by understanding the ground to be part of the aerodynamic system in question, hence the name "ground effect". Starting in the mid-1960s, 'wings' were routinely used in the design of race cars to increase downforce (which is not a type of ground effect). Designers shifted their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coandă Effect
The Coandă effect ( or ) is the tendency of a jet (fluid), fluid jet to stay attached to a surface of any form. ''Merriam-Webster'' describes it as "the tendency of a jet of fluid emerging from an orifice to follow an adjacent flat or curved surface and to entrain fluid from the surroundings so that a region of lower pressure develops." It is named after Romanian inventor Henri Coandă, who was the first to recognize the practical application of the phenomenon in aircraft design around 1910. It was first documented explicitly in two patents issued in 1936. Discovery An early description of this phenomenon was provided by Thomas Young (scientist), Thomas Young in a lecture given to The Royal Society in 1800: More than a hundred years later, Henri Coandă identified an application of the effect during experiments with his Coandă-1910 aircraft, which mounted an unusual engine he designed. The motor-driven turbine pushed hot air rearward, and Coandă noticed that the airflow w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulfstream G650
The Gulfstream G650, G700, and G800 are large Business jet, business jets produced by the American company Gulfstream Aerospace."Gulfstream Introduces the All-New Gulfstream G650" . Gulfstream, March 13, 2008. The G650 model is designated ''Gulfstream GVI'' in its type certificate. The aircraft can be configured to carry from 11 to 18 passengers over a range of at a top speed of . The aircraft is powered by two Rolls-Royce BR700, Rolls-Royce BR725 turbofans, mounted on the rear fuselage. Gulfstream began the G650 program in 2005 and revealed it to the public in 2008. The G650ER is an extended-range version of the G650, adding about by modifying the fuel system, an upgrade offered for existing G650 aircraft. At its introduction, the G650 was the company's largest and fastest busin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
De Havilland Comet
The de Havilland DH.106 Comet is the world's first commercial jet airliner. Developed and manufactured by de Havilland in the United Kingdom, the Comet 1 prototype first flew in 1949. It features an aerodynamically clean design with four de Havilland Ghost turbojet engines buried in the wing roots, a pressurised cabin, and large windows. For the era, it offered a relatively quiet, comfortable passenger cabin and was commercially promising at its debut in 1952. Within a year of the airliner's entry into service, three Comets were lost in highly publicised accidents after suffering catastrophic mishaps mid-flight. Two of these were found to be caused by structural failure resulting from metal fatigue in the airframe, a phenomenon not fully understood at the time; the other was due to overstressing of the airframe during flight through severe weather. The Comet was withdrawn from service and extensively tested. Design and construction flaws, including improper riveting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lockheed Martin F-35 Lightning II
The Lockheed Martin F-35 Lightning II is an American family of single-seat, single-engine, supersonic Stealth aircraft, stealth strike fighters. A multirole combat aircraft designed for both Air superiority fighter, air superiority and attack aircraft, strike missions, it also has electronic warfare and intelligence, surveillance, and reconnaissance capabilities. Lockheed Martin is the prime F-35 contractor with principal partners Northrop Grumman and BAE Systems. The aircraft has three main variants: the CTOL, conventional takeoff and landing (CTOL) F-35A, the STOVL, short take-off and vertical-landing (STOVL) F-35B, and the carrier-based, carrier variant (CV) Catapult Assisted Take-Off But Arrested Recovery, catapult-assisted take-off but arrested recovery (CATOBAR) F-35C. The aircraft descends from the Lockheed Martin X-35, which in 2001 beat the Boeing X-32 to win the Joint Strike Fighter program, Joint Strike Fighter (JSF) program intended to replace the General Dynami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
