The ground-effect machine ‘Ship on a dynamic air cushion’ is a high-speed vehicle that flies within the limits of aerodynamic screen in other words at relatively small (up to several meters) altitude from the water, land, snow or ice surface.
In 1964-1965, the unique world's largest aircraft, the ground-effect machine SM, was designed and developed. Foreign special services called it ‘Caspian sea monster’. This way the Americans decrypted the letters SM on the board of the airplane, which meant ‘seaplane’. The wing-spread of ekranoplan was 37.6 meters, and its length was about 100 m. The perfect flight height ranged from 4 to 14 m above sea level, depending on airspeed. Cruise speed was 430 km / h and the maximum one - 500 km / h. Once it took off with the weight of 544 tons. It was a record for any existing aircraft. Only the Antonov AN-225 ‘Mriya’ was able to break this record later.