What sank it? First, the fuel costs were prohibitive. The vehicle's four Rolls-Royce engines consumed 1,200 gallons of fuel per hour. That was fine during the 1950s and 1960s, when fuel was very cheap, but the costs became more burdensome. The Neoprene skirt that encircled the craft created another problem. Engineers designed the skirt to bend and flex over choppy water while maintaining a bubble of air beneath the skirt. But at 75 mph, the rubber took a beating on most trips. According to Roger Syms and Robin Paine, two former hovercraft pilots who wrote a history of the vehicle, On a Cushion of Air, portions of the skirt needed daily repair or replacement. "When you have a car, you don't expect that you'll have to change the tires every night," Syms says. To make a large-scale hovercraft commercially viable today, Paine says, "There would have to be a huge advance in skirt technology."
This article originally appeared in the May 2013 issue of Popular Science. See the rest of the magazine here.
Give the skirt armor... Line it with chainmail?
I've always been interested in weird watercraft, stuff like ekranoplanes, hydorfoils, hovercraft, and hypothetical supercavitating submarines. I know that they're not always practical but I'm always hoping that technology can catch up.
I had always hoped we would see cars that would finally make +100 mph travel a reality without a pilots license. But everytime a hovercraft came to the market, it was too expensive and conceived as a recreational vehicle. Do the same limits that killed the hoverboats prohibit its use for cars, or are companies simply afraid people won't buy it?
What's wrong with kevlar?
Because nothing full of hot air is...
I didn't know about the gargantuan fuel consumption, but it makes sense. We're talking about maintaining a cushion of air enough to support an entire ship a few inches off the surface, to say nothing of propelling the ship forward at relatively high speeds. Besides, if people really wanted to cross the ocean faster than a ship, they would just use a plane. Planes may use a lot of fuel too... But they aren't running for nearly as long.
Perhaps someday they will be viable. When they solve the skirt issue, that is... Which doesn't seem like a big lift, considering rubber vs. modern composites. Then maybe they could do something about that godawful fuel burn. Electric motors and some sort of tiny nuclear reactor, perhaps?
Always defer to facts rather than philosophy.
The article title is a bit misleading. Hovercraft are extremely useful. They go where no other vehicle will travel. The analogy to a car is not very helpful, hovercraft aren't a replacement for a car any more than a helicopter is a replacement for a bicycle.
Regarding the skirts: A car's wheel is practical only because we have collectively invested more than $1million per mile for an expensive track called a road that allows it to function. The wheel is useless in water, over thick or thin ice and it becomes hopelessly stuck in mud and sand. Hovercraft, however can master all of these surfaces.
Fuel and maintenance are simply the costs of traveling on these surfaces. If you must cross such terrain you can either build a bridge/road (at great expense) or you can spend much less on skirts and fuel. Helicopters also use massive amounts of fuel and require extensive maintenance, but that doesn't mean they aren't "useful". When you need a helicopter a car won't do. Likewise, if you need a hovercraft, a car will not substitute.
Let's put it this way: if you've just fallen through thin ice into freezing water and here comes a hovercraft the last thing on your mind is the hovercraft's cost of fuel and maintenance!
For more on the very practical applications of hovercraft and training to make the most of this incredibly useful technology check out HovercraftTraining.com
When you need to get across some crappy swamp or wet sand somewhere to snatch some dude out from under his handlers and have a chance to get out where few can follow, a hovercraft becomes very useful indeed. Ask the CIA. Still, a model with semi-lightweight retractable wheels could come along and really have detractors eating crow. Materials are getting lighter daily.