Hovercraft construction could be separated into the categories of hull, skirt, engines and fans, controls and fitments. Each should be approached first as a separate entity and then as a part of the integrated whole that needs to complement each other. The selection of the materials is the first stage of the process, and this selection is generally made from an array of products employed in the marine industry, simply because they are designed to resist tough conditions. The interest in small personal hovercraft for leisure purposes has also led to the search for new materials which are cost effective and tough enough to provide a good level of safety for pilot and passengers.
The hull is the major part of an air cushioned vehicle and various types of material have been used here. For smaller craft, lightness is essential, but so is stability and strength. When you see a hovercraft advertised for sale, it should be the first thing that you think of and check. Many smaller types use fiber glass, which is very light but it also has one unfortunate characteristic. It is not to flexible and tends to split and crack if it hits an obstruction with sufficient force. Imagine hovering over rapidly moving water and a rock is sticking up and you will appreciate the hazard. GRP is very difficult and expensive to repair, so is not good choice for leisure use. All these things need to be considered before learning how to fly a hovercraft.
Some manufacturers have started to use expanded high impact plastic hulls. This material is light but more importantly it doesn't split under impact, so is safer for family use. Great strides have been made in the production process so that it has become cost effective enough to be used. Controls are fabricated from marine grade stainless steel, to resist salt water, and all electrical equipment is high grade and double insulated. Plastic is used extensively for fitments and storage space, but in some models hard woods may be employed if a more aesthetic appeal is required.
Another major design feature is the choice and construction of skirt material. Traditionally, a single piece of rip-stop sail cloth was used. Even though this is very tough material, the major disadvantage is that the whole skirt has to be changed if it becomes damaged. One company has produced a skirt made from Kevlar material, possibly the toughest fabric known to man. It resists tearing extremely well, but enough rough treatment will damage anything. For this reason, the skirt is fabricated in sections loosely tie-wrapped together. If one section gets damaged, it is removed and replace very quickly.
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