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Progress D-236
The Progress D-236 was an experimental aircraft engine, a hybrid between a turbofan and a turboprop known as a propfan. Also known as the Lotarev D-236T, the three-shaft geared engine was designed in the 1980s and 1990s to power proposed propfan aircraft such as the Tupolev Tu-334, Ilyushin Il-118, and Ilyushin Il-88. Based on the core of the Ukrainian Progress D-36 turbofan, the D-236 was the first Soviet propfan, and as of 2019 it is still one of only four different unshrouded, contra-rotating propfan engines to have flown in service or in flight testing. Design and development The D-236, an engine with unshrouded contra-rotating propellers, was first investigated in 1979 as the powerplant for the first version of the Ukrainian Antonov An-70. The front propeller was tested on the Antonov An-32 military transport aircraft in 1980, as the An-32's normal Ivchenko AI-20DM engines had about half the rated power of the D-236. However, the anticipated improvements in takeoff perfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yak-42
The Yakovlev Yak-42 (; NATO reporting name: "Clobber") is a 100/120-seat Trijet, three-engined mid-range passenger jet developed in the mid 1970s to replace the technically obsolete Tupolev Tu-134. It was the first airliner produced in the Soviet Union to be powered by modern high-bypass turbofan engines.Gunston, 1997 Development In 1972, the Yakovlev OKB, design bureau started work on a short- to medium-range airliner capable of carrying 100–120 passengers. It was intended to be a replacement for the Tupolev Tu-134 jet as well as the Ilyushin Il-18, Antonov An-24 and Antonov An-26, An-26 turboprop airliners. While the new airliner was required to operate out of relatively small airfields while maintaining good economy, as many Soviet airports had been upgraded to accommodate more advanced aircraft, it did not have to have the same ability to operate from grass strips as Yakovlev's smaller Yakovlev Yak-40, Yak-40. The requirement resulted in the largest, heaviest and most po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris Air Show
The Paris Air Show (, ''Salon du Bourget'') is a trade fair and air show held in odd years at Paris–Le Bourget Airport in France. Organized by the French aerospace industry's primary representative body, the ''Groupement des industries françaises aéronautiques et spatiales'' (GIFAS), it is the largest air show and aerospace-industry exhibition event in the world, measured by number of exhibitors and size of exhibit space, followed by UK's Farnborough Air Show, Dubai Air Show, and Singapore Airshow. First held in 1909, the Paris Air Show was held every odd year from 1949 to 2019, when the 53rd Air Show attracted 2,453 exhibitors from 49 countries and occupied more than 125,000 square meters. Organizers canceled the 2021 show due to the COVID pandemic. It resumed in 2023. It is a large trade fair, demonstrating military and civilian aircraft, and is attended by many military forces and the major aircraft manufacturers, often announcing major aircraft sales. It starts with four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planetary Gearbox
An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the centers of the two gears and rotates, to carry the planet gear(s) around the sun gear. The planet and sun gears mesh so that their pitch circles roll without slip. If the sun gear is held fixed, then a point on the pitch circle of the planet gear traces an epicycloid curve. An epicyclic gear train can be assembled so the planet gear rolls on the inside of the pitch circle of an outer gear ring, or ring gear, sometimes called an ''annulus gear''. Such an assembly of a planet engaging both a sun gear and a ring gear is called a planetary gear train.J. J. Uicker, G. R. Pennock and J. E. Shigley, 2003, ''Theory of Machines and Mechanisms,'' Oxford University Press, New York.B. Paul, 1979, ''Kinematics and Dynamics of Planar Machinery'', Prent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Generator
A gas generator is a device for generating gas. A gas generator may create gas by a chemical reaction or from a solid or liquid source, when storing a pressurized gas is undesirable or impractical. The term often refers to a device that uses a rocket propellant to generate large quantities of gas. The gas is typically used to drive a turbine rather than to provide thrust as in a rocket engine. Gas generators of this type are used to power turbopumps in rocket engines, in a gas-generator cycle. It is also used by some auxiliary power units to power electric generators and hydraulic pumps. Another common use of the term is in the industrial gases industry, where gas generators are used to produce gaseous chemicals for sale. For example, the chemical oxygen generator, which delivers breathable oxygen at a controlled rate over a prolonged period. During World War II, portable gas generators that converted Coke (fuel), coke to producer gas were used to power vehicles as a way o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ilyushin Il-76
The Ilyushin Il-76 (; NATO reporting name: Candid) is a multi-purpose, fixed-wing, four-engine turbofan strategic airlifter designed by the Soviet Union's Ilyushin design bureau as a commercial freighter in 1967, to replace the Antonov An-12. It was developed to deliver heavy machinery to remote and poorly served areas. Military versions of the Il-76 have been widely used in Europe, Asia and Africa, including use as an aerial refueling tanker and command center. The Il-76 has seen extensive service as a commercial freighter for ramp-delivered cargo, especially for outsized or heavy items that cannot be carried by other means. It has also been used as an emergency response transport for civilian evacuations as well as for humanitarian aid and disaster relief around the world. Thanks to its ability to operate from unpaved runways, it has been useful in undeveloped areas. Specialized models have also been produced for aerial firefighting and reduced-gravity training. Design a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mach Number
The Mach number (M or Ma), often only Mach, (; ) is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound. It is named after the Austrian physicist and philosopher Ernst Mach. \mathrm = \frac, where: * is the local Mach number, * is the local flow velocity with respect to the boundaries (either internal, such as an object immersed in the flow, or external, like a channel), and * is the speed of sound in the medium, which in air varies with the square root of the thermodynamic temperature. By definition, at Mach1, the local flow velocity is equal to the speed of sound. At Mach0.65, is 65% of the speed of sound (subsonic), and, at Mach1.35, is 35% faster than the speed of sound (supersonic). The local speed of sound, and hence the Mach number, depends on the temperature of the surrounding gas. The Mach number is primarily used to determine the approximation with which a flow can be treated as an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Noise Pollution
Aircraft noise pollution refers to noise produced by aircraft in flight that has been associated with several negative stress-mediated health effects, from sleep disorders to cardiovascular disorders. Governments have enacted extensive controls that apply to aircraft designers, manufacturers, and operators, resulting in improved procedures and cuts in pollution. Mechanisms of sound pollution Aircraft noise is noise pollution produced by an aircraft or its components, whether on the ground while parked such as auxiliary power units, while taxiing, on run-up from propeller and jet exhaust, during takeoff, underneath and lateral to departure and arrival paths, over-flying while en route, or during landing. A moving aircraft including the jet engine or propeller causes compression and rarefaction of the air, producing motion of air molecules. This movement propagates through the air as pressure waves. If these pressure waves are strong enough and within the audible frequency s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antonov
Antonov (d/b/a Antonov Company, formerly the Aeronautical Scientific-Technical Complex named after Antonov or Antonov ASTC, and earlier the Antonov Design Bureau, for its chief designer, Oleg Antonov) is a Ukrainian aircraft manufacturing and services company. Antonov's particular expertise is in the fields of very large aeroplanes and aeroplanes using unprepared runways. Antonov (model prefix "An-") has built a total of approximately 22,000 aircraft, and thousands of its planes are operating in the former Soviet Union and in developing countries. Antonov Company is a state-owned commercial company originally established in Novosibirsk, Russian Soviet Federative Socialist Republic (RSFSR). In 1952, the company relocated to Kyiv, Ukrainian SSR, then part of the Soviet Union. On 12 May 2015, it was transferred from the Ministry of Economic Development and Trade to the Ukroboronprom (Ukrainian Defense Industry). In June 2016, Ukraine's major state-owned arms manufacturer Ukro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cruise (aeronautics)
Cruise is the phase of aircraft flight from when the aircraft levels off after a climb until it begins to descend for landing. Cruising usually comprises the majority of a flight, and may include small changes in heading (direction of flight), airspeed, and altitude. Airliner cruise Commercial or passenger aircraft are usually designed for optimum performance around their cruise speed ( VC) and cruise altitude. Factors affecting optimum cruise speed and altitude include payload, center of gravity, air temperature, and humidity. Cruise altitude is usually where the higher ground speed is balanced against the decrease in engine thrust and efficiency at higher altitudes. Common narrowbodies like the Airbus A320 and Boeing 737NG cruise at , while modern widebodies like the Airbus A350 and Boeing 787 cruise at . The typical cruising altitude for commercial airliners is . The speed which covers the greatest distance for a given amount of fuel is known as the maximum range spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Takeoff
Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a transition from moving along the ground on a runway. For balloon (aircraft), balloons, helicopters and some specialized fixed-wing aircraft (VTOL aircraft such as the Hawker Siddeley Harrier, Harrier and the Bell Boeing V22 Osprey), no runway is needed. Horizontal Power settings For light aircraft, usually full power is used during takeoff. Large transport category (airliner) aircraft may use a flex temp, reduced power for takeoff, where less than full power is applied in order to prolong engine life, reduce maintenance costs and reduce noise emissions. In some emergency cases, the power used can then be increased to increase the aircraft's performance. Before takeoff, the engines, particularly piston engines, are routinely run up at high po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spar (aeronautics)
In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles (or thereabouts depending on wing sweep) to the fuselage. The spar carries flight loads and the weight of the wings while on the ground. Other structural and forming members such as ribs may be attached to the spar or spars, with stressed skin construction also sharing the loads where it is used. There may be more than one spar in a wing or none at all. Where a single spar carries most of the force, it is known as the main spar. Spars are also used in other aircraft aerofoil surfaces such as the tailplane and fin and serve a similar function, although the loads transmitted may be different from those of a wing spar. Spar loads The wing spar provides the majority of the weight support and dynamic load integrity of cantilever monoplanes, often coupled with the strength of the wing 'D' box itself. Together, these two structural components collectively provide the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
