Personal Leisure Hovercraft
Personal Leisure Hovercraft – Ever since their introduction over 50 years ago, hovercraft have captured our imagination; early hovercraft resembled flying saucers, and appeared to levitate on a cushion of air. Many engineers and hobbyists have tried to create their own hovercraft. Hovercraft are fairly easy to build; you need an engine to drive a fan to provide lift and thrust, plus some mechanism to steer. However, hovercraft are very weight sensitive, and designers need to consider how to make hovercraft durable without compromising performance or safety.
Personal leisure hovercraft design
Hovercraft are now available for personal marine leisure use, and fly over any flat surface, so can also be used over mud and sand – no need to wait for high tide.
Hovercraft also fly over concrete, tarmac, ice and snow, so you can use them to reach a winter cabin. In springtime, ice covered lakes become dangerous for continued snow mobile use, but hovercraft are happy to fly above water or ice.
What to consider when choosing a personal hovercraft
Durability is important – race hovercraft that reach speeds of 70 mph do so by carrying very little weight, so race hovercraft hulls tend to be constructed from very thin lightweight yet not very durable glass fibre.
Leisure hovercraft need to be more durable, especially if you meet an obstacle in your path, (tree or rock) or plan to ride over abrasive rough surfaces such as sand or ice. Latest hovercraft designs tend to be manufactured from HDPE and Carbon Fibre, materials that offer durability and strength, whilst remaining lightweight.
Some hovercraft have a single one-piece skirt, which can be expensive to replace when damaged. Many leisure hovercraft have segmented skirts – each segment replaceable if damage occurs – this damage limitation skirt design is worth considering.
Safety is important. Check that the spinning fans are protected front and rear – some suppliers leave the rear of the duct exposed without a fan guard – no factory inspector would leave high speed rotating fan blades exposed in an open public space. Race hovercraft designs often expose the hot exhaust pipe, whereas leisure hovercraft site the exhaust pipe under an engine cover, out of harms way.
Low centre of gravity is important for cornering; if the hovercraft is too top heavy, it will not turn corners very well. Ask to see video footage of cornering.
Hump. All hovercraft have to overcome the pressure wave commonly referred to in hovercraft circles as The Hump – ask the supplier not how many seats the hovercraft has, check what weight the hovercraft can lift when starting on water, if you don’t get that detail right, you might need to go on a crash diet, and eat fewer pies. Failure to get over hump might stop you getting home safely. Some suppliers fudge payload, hovercraft usually carry 50% more weight when starting on land than when starting from an on-water start, so don’t fall for the “see the number of people flying over the puddle” marketing image, ask how many people the hovercraft can lift when starting on the puddle, river, lake or sea, then consider weight of driver, fuel and passengers.
Some hovercraft have a nasty habit of nose-diving into the water – causing sudden de-acceleration, and usually throwing driver and passengers over the handlebars – doing so could harm your wedding prospects, so choose a hovercraft with anti-plow design.
Some hovercraft have separate engines to provide lift and thrust, whereas integrated designs use one engine and a splitter to provide lift and thrust from one power source. The advantage of the single engine design is less weight, less fuel, and simpler operation with one set of controls for one engine. In the two engine design, the lift engine is usually sited at the front, subject to waves, making the hovercraft nose heavy, and more subject to plowing problems should lift operation be lost, and thrust still applied.
Some suppliers up-rate or modify smaller engines to extract as much power as possible – but engine suppliers don’t like their engines operating at high stress levels. Modifying an engine can invalidate the engine manufacturer’s warranty – check that the hovercraft you choose has sufficient power, and that the engine has not been modified.
For more information visit www.hovercraft.org