An ekranoplane (Russian: анопла́н) is a vehicle resembling an airplane, but operating on the ground effect. This effect can be felt when landing on a commercial flight; just before landing, the downward speed could be felt to decrease. Ground effect (GEV) flying vehicles can fly on any flat surface, with the height from the ground varying according to the size of the vehicle.

During the Cold War, ekranoplanes appeared for several years in the Caspian Sea as large, fast-moving objects. The name Caspian Sea Monster was given by U.S. intelligence. confused by this huge vehicle, which looks like an airplane with the outer wings cut off. After the Cold War ended, this monster manifested itself as one of the Russian military designs flying only a few meters above the water's surface, saving energy and being under enemy radar observation.

The KM, as one of the known models in top secret Soviet military developments, is over 100m long and weighs 540 tons when fully loaded, and can travel at speeds of over 400 km/h, just a few meters above the water's surface. Once they have moved at a certain speed, the ekranoplan is no longer in contact with the water, and can move on ice, snow, or other flat surfaces.

Since the fall of the Soviet Union, commercial development has taken place mostly in the United States.

Shipbuilding company Aerohod (Nizhny Novgorod, Russia) 2014 conducted a test of one model aircraft Tungus. According to the experimental results set to start the development and construction of a device with a capacity from 4 to 70 passengers.