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What Happened To Passenger Hovercraft? (bbc.com)

Posted by samzenpus on from the full-of-eels dept.

An anonymous reader writes: Although much has been written about hoverboards lately, hovercraft have largely faded from public imagination, BBC News reports. The Bond-esque 1960s sensation proved too noisy to roam inland rivers regularly, while too small to compete at sea with a new generation of conventional mega-ferries and high-speed car-carrying catamarans. Military aside, only a 10-minute English route and a Sino-Russian river border crossing keep hopes air-cushioned nowadays, while civilian operators wait for electric propulsion to become practical, aiming to reduce airplane-like noise levels and excessive fuel costs with new technology.

12 of 69 comments (clear)

  1. Full of eels by spaceyhackerlady · · Score: 5, Funny

    Never a good start...

  2. That's silly. by Type44Q · · Score: 5, Interesting

    What happened to passenger hovercraft? That's obvious; the flexibility they provide (amphibious, require little infrastructure) obviously doesn't offset their inherent disadvantages (lack of carrying capacity, poor fuel efficiency, etc) except for military applications. What I want to know is what happened to the hydrofoil? I got to ride on one from H.K. to Macao at a very young age; I remember being mildly disturbed at the speeds we were traveling at... I've never heard a peep about them, however.

    1. Re:That's silly. by hawguy · · Score: 3, Interesting

      What happened to passenger hovercraft? That's obvious; the flexibility they provide (amphibious, require little infrastructure) obviously doesn't offset their inherent disadvantages (lack of carrying capacity, poor fuel efficiency, etc) except for military applications. What I want to know is what happened to the hydrofoil? I got to ride on one from H.K. to Macao at a very young age; I remember being mildly disturbed at the speeds we were traveling at... I've never heard a peep about them, however.

      Turns out they have their own disadvantages. Seasickness and reliability were a big problem with the last attempt to provide hydrofoil service in Hawaii... though it's been over 30 years since then, so maybe they are better now. Even fast catamarans couldn't succeed in Hawaii, though I think their problems were more political than technical.

      http://beatofhawaii.com/hawaii...

    2. Re:That's silly. by Dereck1701 · · Score: 2

      Hydrofoils never caught on because with the technology of the day unless you were traveling stupid proof route, in fairly nice weather with a pretty decent depth they were extremely dangerous. Hit a sand bar or a whale or some other fairly solid object and your ship takes a nose dive at 50 knots. That could (perhaps should) change today with GPS, sonar, radar & computer systems which could nowadays decrease the chances of such incidents or at least blunt their impact but there are still cost/maintenance issues involved with them. More widespread usage could eventually solve these issues (economies of scale & greater production competition) but it'll probably take time especially in as conservative of an environment as maritime travel.

    3. Re:That's silly. by Solandri · · Score: 2

      What happened to passenger hovercraft? That's obvious; the flexibility they provide (amphibious, require little infrastructure) obviously doesn't offset their inherent disadvantages (lack of carrying capacity, poor fuel efficiency, etc) except for military applications.

      As this is /., I'll get into some of the technical details. The resistance a hovercraft encounters is basically energy transferred to the water and dissipated as waves. The slower the hovercraft is moving, the greater this wave resistance. It's greatest when the hovercraft is stationary - in that mode the air cushion is displacing a volume of water equivalent to the vehicle weight, just like a displacement hull ship. As it speeds up, this wave resistance decreases. Basically each "block" of water experiences the weight of the air cushion for less time the faster the hovercraft is moving. So the faster the hovercraft is moving, the less time there is for each "block" of water to start accelerating downwards, the less it moves, and the less wave resistance there is. At extremely high speeds, there's practically no wave resistance - just like a planing hull except without the friction between the hull and water.

      As it turns out, for most commercial ship sizes and speed regimes, the hovercraft doesn't have much if any advantage over a fast catamaran or even a planing hull. But because it's basically an aircraft (and generates thrust via the air), it's a lot more expensive to operate. At extremely high speeds (50-100 knots) the hovercraft is more efficient (albeit still using more energy than traveling at slower speeds). But it's pretty much only the military who really wants ships which can go that fast. (At even higher speeds you're better off with a WIG - wing in ground effect vehicles - which are even more like an airplane.)

      What I want to know is what happened to the hydrofoil? I got to ride on one from H.K. to Macao at a very young age; I remember being mildly disturbed at the speeds we were traveling at... I've never heard a peep about them, however.

      Cost of construction, maintenance, and operation. Like with the hovercraft, it's basically an aircraft. The one you rode from HK to Macau was probably a Kawasaki jetfoil. It was originally designed by Boeing, and licensed to Kawasaki when they couldn't sell any in the U.S. In terms of construction, it's basically an airplane in the shape of a ship (lightweight aluminum construction).

      A displacement hull and even most catamarans are dirt simple to build and maintain and don't really care how much weight you load onto them (less true for catamarans). Hydrofoils, like hovercraft and aircraft, are extremely weight-sensitive. That pretty much limits them to carrying passengers. And the higher construction and maintenance costs means their ticket prices are only sustainable on extremely lucrative routes, like people traveling from Hong Kong to Macau to gamble.

      There's just not much of a market space between a 30 knot conventional ferry and a 200 knot turboprop aircraft. If you want cheap, the ferry is considerably cheaper. If you're willing to pay more, the turboprop will almost always get you there a lot quicker for just a little more cost.

  3. Tom Scott explains by Anonymous Coward · · Score: 4, Informative

    Great video describing the downturn of the hovercraft and concorde etc - https://www.youtube.com/watch?v=eYH1lPm41-0

  4. Did it, once. by pubwvj · · Score: 4, Informative

    I rode on a hovercraft once - over the English channel from France to England. It was an interesting experience. Not worth repeating. It was extremely noisy. I would rather take a slower route.

    1. Re:Did it, once. by Anonymous Coward · · Score: 2, Interesting

      I did too - I loved it. And we took our car too. An hour after disembarking, the car stopped and wouldn't restart ... and then it did. And then it stopped. And started again.

      Then later in the day, it recovered and all was well for the rest of the holiday. We figured the fuel tank had been shaken and stirred, and all the crap in there had decided to take a holiday down the fuel pipe to visit the engine...

  5. Re:Missing Option: Everglades. by swb · · Score: 4, Interesting

    Airboats are still incredibly noisy.

    I rode on one in Louisiana and IIRC it was basically a flat bottomed aluminum boat with a Chevy 454 V8 bolted to a stand in the boat with an actual airplane propeller attached. We all wore shooting muffs.

    It was a pretty fun ride, though. On wide expanses of water, I'd swear it didn't turn per se, but sort of turned sideways until you'd built up enough thrust in the new direction to stop going the old direction. And it worked in water so shallow I couldn't believe it was floating by any definition. We sort of stopped in one shallow spot and I asked the guy "What happens if it gets stuck?" And he said "Well, we have to get out and push" which was fine, other than the 6 alligators I could count within about a 30 foot radius of the boat.

    The whole experience had a touch of "Southern Comfort" (IMDB it) to it. We called a tourist place looking for a ride and the operator said it was out of season for him, but he said something like "Call Pierre Thibideaux, he'll probably take you out" and sure enough we drove to some remote spot on the bayou and this guy with a French accent was waiting with an airboat. Great guy, but of course having seen "Southern Comfort" I was a little worried where we might end up.

  6. Re:the other boats got better by Panoptes · · Score: 2

    Perhaps the main reason the hovercraft never took off is a more prosaic one - limited ability to operate in bad weather and rough seas. I have happy memories of sitting in an ever-lengthening queue in an English Channel ferry port for the best part of a day because of high winds and wave heights.

  7. Capital Letters anyone? by gsslay · · Score: 2

    What kind of world has it become that "Bond-esque" gets a capital letter, but English and Sino-Russian don't?

  8. Re:the other boats got better by tehcyder · · Score: 2

    The cross channel catamarans have long gone too, replaced by a train.

    What they make floating trains now? Where does the track go? Huh?

    --
    To have a right to do a thing is not at all the same as to be right in doing it