Once upon a time hovercraft skirt material was just an afterthought, something added to contain the air pressure generated by the lift propellers above the hull. Indeed, the first hovercraft were simple affairs that didn't need much design finesse to make them work. The other thing was that the variety of material just wasn't there in the early days of the industry. The toughest thing around was probably rip stop sail cloth, which was amply used for all manner and sizes of sailing boats. The material is called 'rip stop' because it does exactly that - the very structure of the material stop any tear form extending, which is achieved by laying different layers of fabric across each other.
In any piece of fabric or soft material made in one layer, a tear will likely promulgate and get progressively worse, if the force that caused it continues. Now imagine two or three layers of the same material bonded together at an angle. When a rip is started and extends one way in one layer of material, the next layer opposes it and it tends to go nowhere, unless of course the force applied is enormous. This is still the principle used in modern skirt fabrication for small personal hovercraft, but the materials are very different.
As well as the employment of new materials, the way in which the whole skirt assembly is created and attached has been radically revised. One manufacturer of leisure hovercraft gives a prize for a special test that they invite any member of the public to perform. A piece of their hovercraft skirt material is cut with a knife, so that each half can be gripped easily with the hands - hovercraft kits and plans. The challenge is simply that anyone succeeding to rip or tear the material any further than the cut will win a huge bottle of the best champagne. Admittedly not a fortune, but it does show considerable confidence in the material used for this use.
Present day personal hovercraft skirts are made from either Kevlar, which is the bullet proof fabric used by the military, or rip stop nylon covered in flexible neoprene. Even though the material is very tough, anything can be destroyed in the right circumstances and one manufacturer has come up with a way of minimizing the hassle of a damaged hovercraft skirt. The company has separated it into several sections, so that if one part is damaged at all, the whole thing doesn't have to be changed.
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