The Lun-class ekranoplan (also called Project 903) is a ground effect vehicle (GEV) designed by Rostislav Alexeyev in 1975 and used by the Soviet and Russian navies from 1987 until sometime in the late 1990s. It flew using lift generated by the ground effect acting on its large wings when within about four metres (13 ft) above the surface of the water. Although they might look similar to traditional aircraft, ekranoplans like the Lun are not classified as aircraft, seaplanes, hovercraft, or hydrofoils. Rather, crafts like the Lun-class ekranoplan are classified as maritime ships by the International Maritime Organization due to their use of the ground effect, in which the craft glides just above the surface of the water. The ground effect occurs when flying at an altitude of only a few meters above the ocean or ground; drag is greatly reduced by the proximity of the ground preventing the formation of wingtip vortices, thus increasing the efficiency of the wing. This effect does not occur at high altitude. The Utka, can engage enemy ships out to its radar horizon (about 35 kilometers/22 miles) but can fire the SS-N-22 out to the missile's 100-kilometer (62-mile) range with over-the-horizon targeting data. The name Lun comes from the Russian word for the harrier. Two were planned, one was built, the other cancelled. However, after its retirement in the late 90s, the heavily-armed ship - which is bigger than a jumbo jet - was left sitting at the unused Kaspiysk naval base. The Russian MD-160, aka 'Ekranoplan', aka 'Utka' - nicknamed the 'Caspian sea monster' - has been transported to Derbent, Dagestan, to become a tourist attraction.
