The Russian Ekranoplan looks like an aircraft but it only flies a few metres above water. Translated the Russian name Ekranoplan means sea skimmer and this is exactly what the Ekranoplan does. The Ekranoplan is what is known as a Ground Effect Vehicle, it operates on the principle of wing in ground effect, where the air gap between a wing and the ground is small enough for the air to be compressed.
Born out of the Soviet Unions Central Hydrofoil Design Bureau it was developed by their chief designer Rostislav Alekseev. Several different Ekranoplan's were developed from 1961 to 1990. Since the fall of the Soviet Union many of the design team from the CHDB have formed a new company with plans to develop new craft for passenger and cargo usage. Also 11 small 5 passenger craft were constructed between 1995 and 1997, they were used in trial commercial operation in USA and the Bahamas...
...The largest Ekranoplan called the KM was built in 1967, it was dubbed the Caspian Sea Monster after the sea it was on when first seen by the west. It was almost twice the length of a Boeing 777-200 but as with all Ground Effect Craft it need only half the wingspan. At over 100 m long, weighing 540 tons fully loaded, the KM could travel over 400 km/h mere meters above the surface of the water. 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.
The important design principle is that the wing lift reduces the further above the surface of land or sea that the ekranoplan "flies". Thus its dynamically stable in the vertical dimension.
These craft were originally developed by the Soviet Union as very high-speed (several hundred km/hour) military transports, and were mostly based on the shores of the Caspian Sea and Black Sea. The largest
could transport over 100 tonnes of cargo. [continued]