Many people are completely unfamiliar with hovercraft, or air cushion vehicles
, as they are often known. Before heading to
for more details, the simple principle behind hovercraft is that air is blown under the flat surface of the craft to maintain a positive pressure that keeps the craft just above the ground—
or water. A flexible skirt around the edge of the craft helps to maintain the pressure and stability, and propulsion is usually provided through a propeller (or two, or four).
I saw my first hovercraft at the 1964 Farnborough Air Show—
a fact which underlines that the culture of the first generations was that of the aircraft industry. By 1966 hovercraft were in service on the Ramsgate–Calais
ferry routes as well as in a number of other military and civil applications.
They have a number of significant advantages over boats. They operate as easily over land as over water, which makes them useful where the route includes sandbanks and shallow water such as the approach to Ryde, Isle of Wight, or the Goodwin Sands between Ramsgate and Calais. Compared to boats they are fast, as they "float" a short distance above the surface, without any contact with the water. But on the downside, being related to aircraft inevitably makes them more expensive to manufacture and operate than a conventional boat. And their ability to operating in heavy seas is generally more limited than boats. The earlier models were also somewhat noisy, making them less popular near urban areas.
For about 30 years regular car and passenger hovercraft were operated across the English Channel, but eventually were withdrawn as the market changed. But there seems to be a renewed interest around the world in using hovercraft where their specific features are well suited to the need, both as ferries and various civilian and military roles. The Canadian Coast Guard operates hovercraft for ice-breaking as well as more conventional duties.
is an enthusiastically run website with loads of photos. A good starting point to browse through the world of hovercraft and their history.
Hovercraft were developed at the same time I entered my teens and I developed my interest in aircraft, and I took my first trip abroad on one of the early cross-Channel hovercraft services. So I have always had a soft spot for them!