Surface-effect vehicle is an aircraft plane that flies at only a few meters or centimeters altitude. The basis of working of these aircrafts is surface effect, that is, considerable increasing of wing lift and reducing of wing drag during the flight immediately over the surface.

     As actually several types of such vehicles have appeared, the following international classification for surface-effect vehicles was developed:
     - type “A” – can fly immediately near the surface only;
     - type “B” – can get off the surface for a while;
     - type “C” – can fly beyond the surface quite a while as an airplane (the type is also named aerodynamic ground-effect craft).

          Other definitions: