EKRANOPLAN

The Lun-class ekranoplan, or Project 903, represents a unique ground effect vehicle (GEV) used in a military capacity. Conceived by Rostislav Alexeyev in 1975, it served in the Soviet and later Russian navies from 1987 until sometime in the late 1990s. This craft achieved flight by utilising the lift generated by the ground effect, which acted upon its extensive wings, keeping it approximately four meters above the water’s surface. Despite its visual resemblance to conventional aircraft, ekranoplans like the Lun do not fall into aircraft, seaplanes, hovercraft, or hydrofoils. Instead, these vehicles are classified as maritime ships by the International Maritime Organization, thanks to their reliance on ground effect, allowing them to glide just above the water’s surface.

Ground effect manifests when flying a mere few meters above the ocean or terrain, markedly reducing drag due to the proximity of the surface. This eliminates the formation of wingtip vortices, thereby enhancing the wing’s efficiency. This phenomenon is absent at higher altitudes.

“Lun” is derived from the Russian word for “harrier.”

DESIGN

The Lun-class ekranoplan was developed based on the experimental KM ekranoplan, colloquially called the “Caspian Sea Monster.” The Lun was propelled by eight Kuznetsov NK-87 turbofans on forward canards, each generating 127.4 kN (28,600 lbs) of thrust. Its structure featured a flying boat hull with a substantial deflecting plate at the base, facilitating takeoff. The maximum cruising speed was 550 kilometres per hour (340 mph). It was outfitted for anti-surface warfare and carried the P-270 Moskit (Mosquito) guided missile. Six missile launchers were mounted in pairs on the dorsal surface of its fuselage, supported by advanced tracking systems in the nose and tail. The sole model of this class ever constructed, the MD-160, entered service with the Soviet Navy Caspian Flotilla in 1987 and was retired in the late 1990s. It remained unused at a Caspian Sea naval base in Kaspiysk until 2020.

A second Lun-class ekranoplan, partially built in the late 1980s, transformed construction. It was reconfigured into a mobile field hospital designed for rapid deployment to any oceanic or coastal location and was named the “Spasatel” (“Rescuer”). Following the disintegration of the Soviet Union in 1991 and the discontinuation of military funding, the construction of the second craft was halted. As of 2021, the unfinished “Spasatel” is stored near the Volga River in an old industrial complex within the central Russian city of Nizhny Novgorod.

The Lun design possessed several limitations. One significant drawback was that, despite its capability to fly at low altitudes due to ground effect, it had to maintain a size as low as 1.5–3.0 meters (5–10 feet) above the water because of its limited wingspan. Consequently, it couldn’t operate in mildly rough seas. Another limitation was its exclusive reliance on the ground effect principle, rendering it unable to ascend to higher cruising altitudes. This requirement for calm seas and the inability to operate above them substantially restricted its deployment options.

SPECIFICATIONS

Crew: 15 (6 officers, 9 enlisted).

Capacity: 137 t (302,000 lb).

Length: 73.8 m (242 ft 2 in).

Wingspan: 44 m (144 ft 4 in).

Height: 19.2 m (63 ft 0 in).

Wing area: 550 m2 (5,900 sq ft).

Empty weight: 286,000 kg (630,522 lb).

Max takeoff weight: 380,000 kg (837,757 lb).

Powerplant: 8 × Kuznetsov NK-87 turbofans, 127.4 kN (28,600 kg) thrust each.

Performance:

Maximum speed: 550 km/h (340 mph, 300 km).

Cruise speed: 450 km/h (280 mph, 240 km) at 2.5 m (8 ft).

Range: 2,000 km (1,200 mi, 1,100 nmi).

Service ceiling: 5 m (16 ft) in ground effect.

Armament:

Guns: two 23mm Pl-23 cannon in a twin tail turret and two 23mm Pl-23 cannon in a twin turret under forward missile tubes.

Missiles: six launchers for P-270 Moskit Sunburn anti-ship missiles.

The ekranoplan market has experienced a revival of sorts. In the previous year, Russia disclosed the sale of six smaller ekranoplans to Iran for undisclosed purposes. Simultaneously, another Russian manufacturer recently revealed the development of a 12-person ground-effect craft designed for civilian use.