Hovercraft can be divided into two main types: Fully amphibious Hovercraft - able to make the transition from water to land and vice versa. Sidewall Hovercraft - effectively a catamaran with low displacement hulls and flexible structures forward and aft. Pressurised air is retained between the hulls which elevates the vessel thus reducing the drag through the water.

Courier - landing at Lee-On-Solent Hovercraft Museum Open Day 1995

Fully amphibious hovercraft are propelled by air screws (propellers) and are supported by a cushion of air retained within a flexible structure. Once on "hover" the body of the Hovercraft is lifted and there is no hard structure contact with the surface being transited. Over relatively smooth surfaces, sea or land, the flexible structure and cushion of air provides a very low friction interface, consequently high speeds can be achieved. Fully amphibious hovercraft, depending on size and type, can typically travel at 30 to 50 knots over relatively smooth water. Speeds are reduced as the sea state worsens because of the increase in wave drag on the flexible structure. Additionally strong headwinds will reduce the efficiency of the air screw propulsion.

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