Air-cushion Vessel

A craft supported wholly or partly by a pressurised cushion of air close to the surface.

A hovercraft is the familiar example. Lift fans supply air beneath the craft, often retained by a flexible skirt, while separate or combined propulsion moves and steers it over water, mudflats, ice or suitable land.

Because it operates with little or no conventional hull immersion, an air-cushion vessel has handling characteristics different from a displacement boat, including sideways drift, limited grip and sensitivity to wind and surface conditions. It remains subject to the navigation requirements applicable to its operation.