# Reduced volume flow in a hovercraft

## Main Question or Discussion Point

I was wondering what will happen to a hovercraft which is designed for a given air film thickness, is. slightly lifted above its air film, will the hovercraft start behaving like an helicopter, which uses the action- reation phenomenon to keep itself in the air or it will still continue to slip on the air film.

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most modern 'hover crafts' are miss-named and should be called 'skimmers' as they sit on a cushion of air formed by the skirt that lightly scuffs along the ground. I suspect what your refering to would be a true hovercraft which utilities an air curtain to form the edge of the air pocket.

In both cases the craft is lifted by the higher pressure under the craft much like a lid on a pot of boiling water "hovers" above the pot and can be easily spun. To take the analogy further, if you held the lid 1 inch above the pot it would take a LOT of boiled water to hold the weight of the lid... similarly the skimmer/hover craft would take a large jump in power to float above the ground effect... may as well just jump in a helicopter. My old skimmer uses a 5 h.p. engine for lift, and that's probably overkill, while a helicopter uses... you get the picture.

thanx for the reply flyboy, but I wanted to know wether a skimmer if lifted with some external force, such that partly the weight is divided in between air film and a force such that both of them are in perfect equilibrium, then ,will the hovercraft still be able to produce a lift even if the force has lifted to a position above its air film...what will be the value of height of skirt to completely shift its weight to the balancing force.

CWatters