Hovercrafts travel on an air-cushion and can travel over earth, water and ice. They operate by creating a cushion of low-pressure, high volume air between the hull and ground. The hovercraft travels about 8 inches (205 mm) to 25 inches above surface. Power is typically provided by high performance engines like the Rolls-Royce Proteus marine turbo engines powering “lift fans.” Hovercrafts steer using pylon-mounted steerable propulsion propellers.
The Largest Non-Military Hovercraft In The World
The BHC SRN4 was the world’s largest non-military hovercraft. It carried 60 vehicles and up to 418 people. The craft weighed 190 long tons (193 t) and traveled at a speed of 83 knots (154 km/h). The SRN4 operated in the English Channel between 1968 and 2000.
The British Hovercraft Museum has more information.