Beginning from the 80-s, the Alekseev’s Design Bureau is actively busy with the development of planing ships and boats with air cavity (bottom air lubrication).
The basic idea is rather simple. Ship friction drag is reduced due to air interlayer between bottom and water as the air density is much less than that of water. The ship hydrodynamic drag is reduced by 30% due to lower air viscosity as compared to water. The power consumption needed for air lubrication shall not exceed 2 to 3 % of the total engine power.
The economic efficiency of a ship of the type is expressed in reduction of fuel consumption and also in design simplicity, which reduces construction and operational costs.
The absence of protruding parts available on hydrofoils and shallow draught enable operation of such ship in shallow water regions.
Air-cavity high-speed ships and boats are being successfully operated both at sea and on rivers.
During 80-s – 90-s the Alekseev's Design Bureau developed passenger vessels with speeds up to 30 knots (55-60 km/h) and of up to 150 passengers capacity and cargo vessels with speeds of 30 knots and more and up to 120 tons of cargo capacity.
Apart from commercial ships, the boats of 100 tons displacement and speed of 50 knots are developed and built in series for Russian Customs and Coast Guard.
Basing on experience and done research, the air-cavity riverine and sea ships and boats, including passenger, cargo-and-passenger and special-purpose vessels, as follows can be developed:
- passenger capacity up to 250 persons;
- cargo capacity up to 180 tons;
- speed up to 50 knots.