A-90 Orlyonok

The A-90 Orlyonok (Russian: Орлёнок, English: "Eaglet") is a Soviet "ekranoplan" - a ground effect vehicle - that was designed by Rostislav Evgenievich Alexeev (1916-1980) 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 3,000 m (9,800 ft), placing between Class A - which is limited to ground effect, and Class C, which exploits the ground effect only during take-offs and landings.

The Orlyonok was designed as a transport and also as a beach assault unit. 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-12turboprop, 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 could be vectored either under the wings to produce PAR thrust for takeoff, or over the wings to generate extra propulsion and increased lift. Under cruise conditions and in ground effect, the front engines could be shut off since their power was unnecessary to keep the aircraft in the air, this also minimized intake of water, salt and ingestion of 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 behind the main wings.

The front end of the Orlyonok was hinged behind the radar dome and the whole assembly could open sideways to speed disembarkation of the infantry it carried, or of a BTR APC. The Orlyonok had a built in folding ramp that allowed it to load and unload vehicles with no external support.

There are now new plans to resume production of the Orlyonok. The craft would be built in Petrozavodsk

Specifications (A-90)

General characteristics

• Crew: 6
• Capacity: 150 personnel
• Payload: 28,000 kg (61,730 lb)
• Length: 58.1 m (190 ft 7 in)
• Wingspan: 31.5 m (103 ft 4 in)
• Height: 16.3 m (53 ft 5 in)
• Wing area: 304 m² (3,272 ft²)
• Max. takeoff weight: 140,000 kg (308,647 lb)
• Powerplant:
  • 2 × Kuznetsov NK-8-4K turbofan, 103 kN (23,155 lb_f) each
  • 1 × Kuznetsov NK-12MK turboprop, 152 kN (34,171 lb_f)

Performance

• Cruise speed: 400 km/h (248.5 mph)
• Range: 1,500 km (932 mi)
• Service ceiling: 3,000 m (9,842 ft)