| 词条 | A-90 Orlyonok | ||||||||||||||||
| 释义 |
The A-90 Orlyonok (Russian: Орлёнок, English: "Eaglet") is a Soviet ekranoplan (a ground effect vehicle) that was designed by Rostislav Evgenievich Alexeyev of the Central Hydrofoil Design Bureau. The A-90 uses ground effect to fly a few meters above the surface. The Russians classify it as Ekranoplan Class B - it can achieve an altitude of {{convert|3000|m|ft|abbr=on}}, placing between Class A - which is limited to ground effect, and Class C, which exploits the ground effect only during take-offs and landings. HistoryThe Soviet Navy command of the 1960s was very interested in a fast military transport capable of carrying a large payload. The Central Hydrofoil Design Bureau was one of the organizations working on this top secret project, about which little was known until the fall of the Soviet Union. Chief Designer R.E. Alexeyev designed several prototypes in the 1960s. At the start of the 1970s, Alexeyev designed a medium-sized Ekranoplan to be used as a military transport. The new vehicle was named "Orlyonok" ("Eaglet"). The first flying unit (S-23) was initially tested on the Volga River in the autumn of 1972, and the next year dismantled and transported to the Caspian Sea for continued testing. In 1975 the S-23 crashed during testing, later proved to be due to a deficiency in the alloy used for the hull. A different alloy was used in all subsequent units built. Development and designThe Orlyonok was designed as a transport and also as a beach assault vehicle. Unlike other Soviet Ekranoplan designs, the Orlyonok was amphibious and was equipped with wheels for beaching and land based takeoffs. The layout of the engines on the Orlyonok was unusual and a testament of the special needs of such an unconventional aircraft. Mounted in the top of the tail, it featured a massive Kuznetsov NK-12 turboprop, the most powerful turboprop ever made, which provided cruise power. The nose of the aircraft mounted two turbofan engines with the intakes on top of the nose and the exhaust along the side of the fuselage, the thrust of these engines being vectored under the wings to produce PAR thrust (increased lift and extra propulsion) for takeoff. Under cruise conditions and in ground effect, the front engines could be shut off since their power was unnecessary to keep the aircraft aloft; this also minimized intake of water, salt and low flying birds. Both takeoff and landing were assisted with large span-length flaps that greatly increased lift and could capture PAR thrust for increased air pressure. Water landings were assisted with a hydro-ski that extended out of the belly of the craft below the main wings. The front end of the Orlyonok was hinged behind the radome and the whole assembly could open sideways to speed disembarkation of the infantry it carried, or of a BTR armoured personnel carrier. The Orlyonok had a built in folding ramp that allowed it to load and unload vehicles with no external support. There were plans to resume production of the Orlyonok. The craft would be built in Petrozavodsk.[1] ProductionOverall only five units were built:
The A-90 entered military service in 1979. Units S-21, S-25 and S-26 remained in active service at least until 1993. Operators
Specifications (A-90){{aircraft specifications|plane or copter? = plane |jet or prop? = both |ref = {{cn|date=November 2016}} |crew = 6 |capacity = 150 personnel |payload main = 28,000 kg |payload alt = 61,730 lb |length main = 58.1 m |length alt = 190 ft 7 in |span main = 31.5 m |span alt = 103 ft 4 in |height main = 16.3 m |height alt = 53 ft 5 in |area main = 304 m² |area alt = 3,272 ft² |airfoil = |empty weight main = |empty weight alt = |loaded weight main = |loaded weight alt = |useful load main = |useful load alt = |max takeoff weight main = 140,000 kg |max takeoff weight alt = 308,647 lb |more general = |engine (jet) = Kuznetsov NK-8-4K |type of jet = turbofan |number of jets = 2 |thrust main = 103 kN |thrust alt = 23,155 lbf |engine (prop) = Kuznetsov NK-12MK |type of prop = turboprop |number of props = 1 |power main = 11,033 kW (NK-12MV) |power alt = 14,795 ehp |max speed main = |max speed alt = |cruise speed main = 400 km/h |cruise speed alt = 248.5 mph |stall speed main = |stall speed alt = |never exceed speed main = |never exceed speed alt = |range main = 1,500 km |range alt = 932 mi |ceiling main = 3,000 m |ceiling alt = 9,842 ft |climb rate main = |climb rate alt = |loading main = |loading alt = |thrust/weight = |power/mass main = |power/mass alt = |more performance = |guns = 2 x 12.7 mm machine guns in twin dorsal turret |avionics = }} See also
External links{{Commonscat|A-90 Orlyonok}}
References1. ^{{cite web|url = http://en.rian.ru/mlitary_news/20120127/170987800.html|title = RIA Novosti|ref = harv}} 10 : Aircraft manufactured in the Soviet Union|Aircraft with contra-rotating propellers|Ekranoplans|Mixed-power aircraft|Soviet military transport aircraft 1970–1979|Turboprop aircraft|Low-wing aircraft|T-tail aircraft|Aircraft first flown in 1972|Alekseyev Central Hydrofoil Design Bureau |
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