Hovercrafts float on a cushion of air, letting you travel over water, dry land and swamps easily. Because there's no friction between the surface and the vehicle, it can achieve great speeds over water and frozen lakes. Invented in the 1950s by Sir Christopher Cockerell, large hovercrafts are used to transport passengers and vehicles across the English Channel. The U.S. Navy uses large hovercrafts as well, called LCACs. Hovercrafts need a durable skirt around their perimeter to entrap air. You can make skirts out of various materials, but the skirt has to be "heavy duty" and able to withstand abrasions.
Rubber sheeting is the preferred material because of its strength and durability. Rubber sheeting is available from industrial supply houses. The hovercraft design engineer will specify the correct thickness, strength characteristics and weight. The engineer will also specify the exact size to cut the sheeting, and how to glue it together. Rubber sheets are available in neoprene or other compounds, with some types of sheeting having internal fiberglass cloth reinforcement. The World Hovercraft Organization states hovercraft skirts are made out of neoprene coated nylon.
Synthetic Canvas Cloth
Various canvas cloths make suitable skirts for light hovercrafts. Since the skirt has to be thick and durable, sewing and gluing two or more cloth layers together add to the strength factor. The cloth itself should be a strong synthetic, such as polyester or nylon. Always keep in mind the skirt must have abrasion-proof characteristics. The cloth also must have air proofing as well, so various rubber coating sprays that remain flexible when cured should be used.
Thick Vinyl Sheeting
Thick vinyl sheeting is adequate but weak. Use vinyl for light-use hovercrafts only. If your hovercraft has to go far offshore or if life-sustaining factors are involved, this is not a suitable material. Vinyl, however, is an inexpensive material for light duty or "hobby" hovercrafts. The hovercraft designer has to assess the intended use of the vehicle, and determine whether vinyl is suitable to use.
Old tires have thick rubber and can be used effectively to make a skirt. Obtain a quantity of non-steel belted tires of the same size from a recycling yard, and cut the sidewalls off. Leave about 2 inches of sidewall on each side of the thread to make an attachment lip or flange on the hovercraft. The other side needs a lip too, to maintain stability on the ground. Then make a cut perpendicular to the thread, so a U-shaped strip of rubber is left. Attach the strips together to make a continuous band. Using old tires is highly experimental, and may or may not work for your hovercraft. A professional engineer can counsel you on how to correctly bond the tire strips together. If you are making a small round hover-board, one large truck tire may suffice.