Question: First of all, what is a hovercraft?
Merriam Webster defines a hovercraft
as: a vehicle that is supported above the surface of land or water by
a cushion of air produced by downwardly directed fans.
The Encyclopedia Britannica says the following: A vehicle supported above the surface of land or water by an air cushion, produced by downwardly directed fans, enclosed within a flexible skirt beneath the hull.
The concept was first proposed by John Thornycroft in the 1870s, but a working model was not produced until 1955, when Christopher Cockerell solved the problem of keeping the air cushion from escaping from under the vehicle, and formed Hovercraft Ltd. to manufacture prototypes. Problems with skirt design and engine maintenance have restricted the vehicle's commercial application; today hovercraft are used mainly as ferries.