Slashdot Mirror

← Back to Stories (view on slashdot.org)

Faster Than Supersonic Travel - Underwater

Posted by Hemos on from the gimme dept.

waimate writes "This fascinating article describes a scheme devised by the Soviet Union for superfast underwater travel - faster than Concorde. The idea is to use Cavitation - an effect usually the enemy of marine architects, and turn it to an advantage, creating vessels (initially torpedoes) encased in a bubble of vacuum and powered by rockets. All under the water. Watch out for that mullet !"

3 of 219 comments (clear)

  1. Stealth this is not -- more like murder by Morgaine · · Score: 5

    Any living organism caught by the shock front from this thing is going to be jelly. A megawatts drive underwater would translate directly into millions or billions of fish dead on each trip, and probably several boats and human lives lost as well for good measure.

    Someone's got to be kidding.

    --
    "The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
  2. Somebody has way too much time on their hands... by CyberPup · · Score: 5

    Sheesh, give a little techno-babble to a reporter and he has everyone dreaming about daily bullet trips across the Atlantic. Gimme a break.

    This technology is fairly reasonable for what it's being used for (blind, dumb, fast, small things).

    It won't scale to large vehicles, and most reasonable humans have an aversion to travelling in blind, dumb, fast things anyway.

    Here's a short list of "strikes against it" that immediately come to mind:

    (1) Hello, it's blind. How the heck is it going to see where it's going? Navy ships' passive sonar capability is seriously reduced at speed because of the noise being produced by the ship going through the water (and the increased noise of the ship's machinery). Active sonar? Well, that *might* help a little, but echo from active sonar has to be heard too (see above).

    (2) Most of the marine life (including seaweed, etc) stays relatively close to the surface. Great, you say -- make the thing travel deeper to avoid skewering whales, etc. Well, that'd be nice, but it's a *lot* harder to cavitate at depth due to the increased pressure (and reduced temperature) -- and the relationship is not a proportional one. Besides being harder to cavitate in the first place, it'd be harder to maintain the bubble around the vehicle (because sea pressure would be trying to collapse it).

    (3) Even if you could see where you were going, how would you turn? Control surfaces on the vessel wouldn't do anything because they're in a bubble. Change the direction of the rocket? Kill the bubble.

    (4) Rockets aren't exactly green machines either. Pump our oceans full of chemicals? I don't think so.

    (5) The speed required to maintain a cava-bubble (tm) around a large commercial vessel would be MUCH greater than that required to create/maintain a bubble around a small object like a bullet or a torpedo.

    (6) Revisiting the "can't see" issue a bit -- assuming they *could* get active sonar to work from within a noisy bubble, what kind of range/warning is it going to give at those speeds? Ever drive really fast at night? Headlights don't give you a whole lot of reaction time, do they? This situation would be much worse.

    (7) This is currently being used for non-manned things that we don't care about. They either run into something or blow up or whatever. Great. Ever wonder what the stopping experience is going to be like for humans? Think about it -- the speed creates the "bubble" which eliminates the drag. Okay, we reach our destination, start to slow down -- bubble collapses -- but guess what, we're still going pretty fast -- now we have a ton of drag slammed onto us. And people whine about a airliner slowing down after a landing. :o)

    (8) Cost? Well, I dare say it'd be a heck of a lot more costly than the Concorde.

    (9) If people are interested in travelling on submarines, why don't we have commercial submarines now?

    -- CP (Who, by the way, spent several years on submarines; and spent three years teaching Heat Transfer & Fluid Flow)

  3. It'll never happen by John+Jorsett · · Score: 5

    Environmentalists have conniptions over sonar discombobulating whales migration patterns and maybe even deafening them. They also accuse the supersonic Concorde of contributing to the degradation of the ozone layer. Now combine the two in the form of supersonic underwater travel and you may as well just paint the target on your back for Greenpeace. Had this emerged before environmentalism took such a hold, maybe it would continue to be used, but attempting to introduce it today just isn't going to fly. And I hate to say it, but just maybe that would be a good thing for once.