We should be very careful what we wish for. Back in the 60s I used to watch Super Car on TV, with Mike Mercury the puppet character and wished that we all had our own personal floating car that didn't depend on wheels or anything else. Well now we have it! Small personal hovercraft are making a splash everywhere all over the globe, and the price is well withing reach of ordinary mortals like us. For the sporting enthusiast, around 10 000 dollars is considered within reach and you could easily spend that for a top line quad or speed boat. However, air cushioned craft, for that is the real name of the hovercraft, are none of these.
First off, you don't need wheels or a propeller to get these things moving, and moving fast! There's no drag on the vehicle except air flow, which is at the same time an advantage and a disadvantage. With no wheels on the ground , propeller or rudder in the water, it takes quite a while to slow down, stop or change direction. All this means is that there is a learning curve when starting to operate small hovercraft, so it's a no-brainer when it comes to driving it around.
Personal hovercraft have been around for some decades, but not in it's present form. Recent developments in material technology and construction methods have ensured that the price is right, while safety and maintenance are top class. For example, the first hovercraft were made with hulls of glass fiber, which tended to split when they hit something - not a very good advertisement for the industry! Nobody wants a vehicle that breaks in half and takes a lot of money to put back in order, so it was back to the drawing board for the designers. Click to see site
The skirts too have had a complete overhaul. Originally they were made out of rip stop sail cloth, which is used for the big sailing boats. New materials include neoprene coated nylon and kevlar, which is an incredibly tough material capable of stopping bullets. In addition, the engines come in choices of size and are almost maintenance free, apart from popping some oil in now and again. Personal hovercraft transport is certainly taking off ans set to grow in the coming years. Racing enthusiasts like the way you have to throw your weight around to steer them and the family man appreciates the modern commitment to safety.
Very small hovercraft such as those made as children's toys are huge fun and have lots of advantages over their bigger cousins. the concept of using air pressure underneath a vehicle as a means of transport was first postulated in 1870, but the materials and engines required to create one were simply not available at that time. Due to these constraints, the first hovercraft appeared as children's toys, which must have helped immensely in their development.
Most people have seen the table game at the seaside where two players stand opposite each other and try to knock a flat plastic disc into the opposing goal. Basically, the disc is an air cushioned vehicle, but it doesn't produce it's own lift. The air pressure that lifts it comes from small holes drilled into the table driven by an electric pump underneath. Hardly a practical means of propulsion for a full size hovercraft, but it does demonstrate the principle very nicely.
Some enterprising kids have even constructed (almost) working one-man ACVs from a simple board and a vacuum cleaner. There isn't quite enough lift to support the vacuum cleaner as well, so a pipe extension is need so that there's a little mobility. I haven't seen one of these, but I'm sure they exist on Youtube. I strikes me that stability would be a major problem though, as there is not design the underneath surface of the board and the skirts are normally very basic. See http://leisure-hovercraft.com
With the advent of molded plastic materials and relatively powerful small DC electric motors, battery powered hovercrafts of a reasonable size started to appear. The real enthusiasts build their own using balsa wood for lightness and two stroke aero engines for lift and forward thrust. These little beauties can reach speeds of 30 to 40 kph and are controlled by radio from a central station with a joy stick for the steering. The great thing about building models is that it's just change of scale to make a working model big enough to ride, and then it gets really exciting!
The dynamics of larger craft are quite different however. Although the principle is the same, larger volumes of air just don't act in the same way. Variations in pressure cause turbulence and this affects the handling of the hovercraft. The bigger types will tend to 'bounce' up and down a little, and also the turbulence will subtly affect the handling. The sheer inertia of a heavier machine means that stops and turns need to be anticipated well in advance, instead of reactng to them as they appear.