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Boat skimming across a lake

  1. Apr 24, 2007 #1
    Could I build a boat that skims across the surface of a lake like a stone and only needs an injection of thrust from an engine now and again to keep it going? Perhaps such a boat would have a rotating outer part and a stationary inner part for passengers.
  2. jcsd
  3. Apr 24, 2007 #2


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  4. Apr 25, 2007 #3


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    If it would have to spin like the stone, that would be a bit of a tough nut to crack. I can't say I have seen it done, but there's nothing saying it can't. I think there would be a lot of trial and error.
  5. Apr 25, 2007 #4
    Well basically if your boat s stable in still state. then a slight motor thrust from te rear should do the trick
  6. Apr 25, 2007 #5


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    Newton's first law..... if you get the drag down near zero, you won't need much thrust. But even with a hydrofoil or related concept (how 'bout a ground-effect aircraft?), your drag will still be significant.
  7. Apr 25, 2007 #6


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    There's also the ever-popular wing-in-ground-effect (WIGE) vehicle. It's half-way between a hydroplane and an aeroplane. Google the 'Caspian Sea Monster' for an extreme example. :biggrin:

    edit: How'd you sneak in there like that, Russ?
    Last edited: Apr 26, 2007
  8. Apr 25, 2007 #7
    Well at any drag coefficient, the highest for boat is about 0.3, a motor can handle the job
  9. Apr 27, 2007 #8
    Thr rotation of the outer part would need to be countered by the inner part turning slowly or some other way.
  10. May 2, 2007 #9
    common ocean racers sorta do that
    the boat flys between waves
    thats why a throttle man is very important
    to keep from over reving and blowing up the hi-powered motors
    when the hull and props leaves the water
    they are faster in waves then in flat water

    both hydrofoil and air cussion craft donot skip
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