Description: The results of researches of nonlinear and non-stationary aerodynamic characteristics of wings with different wing planform depending on flow mode, altitude above wing-in-ground effect plane and trajectory sloping angle. The dependences of aerodynamic characteristics on motion rates of considered lifting surfaces are obtained. It was estimated that the «dynamic cushion» effect is able to overcome «wing-in-ground effect plane» influence in horizontal steady flight. There were given the recommendations of considering the «dynamic cushion» effect in aerodynamic design of aircrafts.
Keywords: wing, environment division plane, 'wing-in-ground effect plane', vertical plane, slope of flight path