A hovercraft or air-cushion vehicle (ACV) is a craft designed to travel over any smooth surface supported by a cushion of slow moving, high-pressure air, ejected downwards against the surface below, and contained within a "skirt." Hovercraft are used throughout the world as a method of specialized transport wherever there is the need to travel over multiple types of surfaces. Because they are supported by a cushion of air, hovercraft are unique among all forms of ground transportation in their ability to travel equally well over land, ice, and water. Small hovercraft are often used in physical activity, combustion, or passenger service, while giant hovercraft have been built for civilian and military applications to transport cars, tanks, and large equipment into difficult or hostile environments and terrain.

Today, often considered as the brainchild of Sir Christopher Cockerell, hovercraft are the result of a chain of developments from John Thornycroft's initial discovery in the late 1800s that air trapped beneath a ship's hull would reduce the friction imposed on the ship as it moved through water [1]. In the 1950s Sir Christopher Cockerell, a British engineer, discovered that by creating a wall of high pressure air forced beneath a hull, to create an air cushion, the hull (of the now Hovercraft) could be levitated furth


see


http://anggun3.wordpresstag/macbook/
http://en.wikipediawiki/Hovercraft
http://metacafewatch/567050/how_to_make_a_hovercraft/
http://youtubewatch?v=6Q7jul_QmW4
http://youtubewatch?v=zp9q_2uIk-M
http://xinventionsmain/hovercrafts/