A high-speed air-supported vehicle capable of multiple mode operations as both a water-contacting vehicle and an aircraft includes an aero roll-stabilizing plan form, a stabilizing ski/hydrofoil below a planing surface of a hull portion of the aero roll-stabilizing plan form for providing stabilization and lift to the plan form in at least one mode of operation, the ski/hydrofoil being mounted to a front underside of a hull portion of the aero roll-stabilizing plan form and being mounted forward of a center of gravity of the plan form, whereby a leading edge of said plan form is kept at a substantially constant level with respect to a surface of water during at least one mode of operation. A stabilizing ski provides stabilization and lift in at least one mode of operation. A flexible ski mount is provided for mounting the stabilizing ski to the aero roll stabilizing plan form. Trim flaps are provided for altering the direction of the plan form, and turning vanes are provided to reduce turbulence originating near the edge of the tip plates.