Ekranoplan

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Ekranoplan KM 'Caspian Sea Monster'
Ekranoplan KM 'Caspian Sea Monster'

An ekranoplan (Russian: экранопла́н, literally "screen plane") is a vehicle resembling an aircraft but which operates solely on the principle of ground effect (in Russian эффект экрана effekt ekrana - from which the name derived). Ground effect vehicles (GEV) fly above any flat surface, with the height above ground dependent upon the size of the vehicle. Ekranoplan design was conceived by revolutionary Soviet engineer Rostislav Alexeev.

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[edit] Monster Sightings

During the Cold War, ekranoplans were sighted for years on the Caspian Sea as huge, fast-moving objects. The name Caspian Sea Monster was given by US intelligence operatives who had spotted the huge vehicle, which looked like an airplane with the outer halves of the wings removed. After the end of the Cold War, the "monster" was revealed to be one of several Soviet military designs meant to fly only a few meters above water, saving energy and staying below enemy radar.

[edit] Specifications

The ekranoplan has a lifting power of 1,000 tonnes (984 LT), among the largest ever achieved. The KM, as the Caspian Sea Monster was known in the top secret Soviet military development program, was over 100 metres (328 ft) long, weighed 540 t (531 LT) fully loaded, and could travel over 400 kilometres per hour (249 mph), mere meters above the surface of the water.[1] [2]. Another model was the Lun-class, entering service with the Black Sea Fleet in 1987; the Lun-class vehicles had a top speed of 297 knots (550 km/h).

The important design principle is that wing lift is reduced as operating altitude of the ekranoplan is increased (see ground effect). Thus it is dynamically stable in the vertical dimension. Once moving at speed, the ekranoplan was no longer in contact with the water, and could move over ice, snow, or level land with equal ease, though flight over land would have involved extreme risks unless the surface were very dependably flat.

[edit] History

These craft were originally developed by the Soviet Union as very high-speed military transports, and were based mostly on the shores of the Caspian Sea and Black Sea.[citation needed] The largest could transport over 100 t (98 LT) of cargo. The development of ekranoplans was supported by Dmitri Ustinov, Minister of Defence of the USSR. About 120 ekranoplans (A-90 Orlyonok class) were initially planned to enter military service in the Soviet Navy. The figure was later reduced to fewer than thirty vehicles, planned to be deployed mainly for the Black and the Baltic Soviet navies. Marshal Ustinov died in 1985, and the new Minister of Defence Marshal Sokolov effectively stopped the funding for the program. The only three operational A-90 Orlyonok ekranoplans built (with renewed hull design) and one Lun-class ekranoplan remained at a naval base near Kaspiysk.[citation needed]

The two major problems which the Soviet Era Ekranoplanes faced were: 1) poor longitudinal stability and 2) a need for reliable navigation & automatic control systems more advanced than any available at the time.

Since the fall of the Soviet Union, ekranoplans have been produced by the Volga Shipyard[3] in Nizhni Novgorod located at 56°21′58.08″N, 43°52′14.26″E.

[edit] Development

Besides the development of appropriate design and structural configuration, special automatic control systems and navigation systems are also being developed. These include special altimeters with high accuracy for small altitude measurements and also lesser dependence on weather conditions. According to many extensive experiments and research activities, it has been shown that "Phase Radio-altimeters" are most conducive for such applications as compared to laser, isotopic or ultrasonic altimeters.[4]

As of 2008-02-09, two ekranoplans could be seen on Google Earth at Kaspiysk, The Lun , located at 42°52′54″N, 47°39′24″E and an Orlyonok at 42°52′50″N, 47°39′57″E. A structure on a nearby beach may be a third disassembled ekranoplan.

Even today R&D activities are being carried out for such vehicles in many countries which include Russia, USA, China, Germany, UK, Australia and many others. Other future projects include the horizontal take-off and horizontal landing of Aerospace Planes(ASP) using ekranoplans.



[edit] References

  1. ^ http://www.theregister.co.uk/2006/09/22/caspian_sea_monster/
  2. ^ Aerospaceweb.org | Ask Us - Ground Effect and WIG Vehicles
  3. ^ Volga Shipyard
  4. ^ COMPARATIVE ANALYSIS OF DESIGN VARIANTS FOR LOW ALTITUDE FLIGHT PARAMETERS MEASURING SYSTEM by Prof.Alexander Nebylov, Sukrit Sharan, published in the 17th IFAC Symposium for Automatic Control
  1. "EKRANOPLANES- Controlled Flight Close to the Sea" by Prof.A.V.Nebylov, WIT Press.
  2. "Complex Algorithms of Parameters Measuring Systems for Motion Close to the Sea" by Sukrit Sharan(Aerospace Trainee from India) , IX Conference for Young Scientists, CSRI-ELEKTROPRIBOR, March 2007, St.Petersburg, Russia.
  3. "Quality Measurement Criteria for Flight Close to the Sea Surface" by Sukrit Sharan, Seminar on 'Aeronautics & Space', 9-13 April, 2007 St.Petersburg State University of Aerospace Instrumentation, Russia.
  4. "Easy Ways to Study Ground Effects" by Aubin S.Y., Monchaux J., 2001.

[edit] See also

[edit] External links