Displacement - much more

Discussion in 'Sailboats' started by tranmkp, Oct 27, 2010.

  1. tranmkp
    Joined: May 2002
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    Location: Texas

    tranmkp "wherever you go. there you are"

    Help me understand please - sailboat displacement - to me you have heavy, in the water (sticky) and you have light, out of the water (not sticky) Sticky being surface area. I suppose the goal is to find something in between..

    So what would happen to say for sake of discussion, a westsail 32, we all know this boat - a hull speed heavy displacement boat with a comfortable motion, What would happen if we duplicated the 32 all in carbon fiber? If we kept the original ballast weight Im sure the boat would be much higher on her waterline. Ok, now we have to add additional ballast to bring her on her lines. Now with all that additional ballast you can add a taller more powerful rig. If you did that then wouldnt you have a boat with a very violent roll and motion? Suppose you kept the original rig with all the addiotional ballast - what would happen then?
  2. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    The boat would of course be stiffer. You can lighten any normal hull and put the weight back down low, given enough money and effort. Then you'd carry sail longer before reefing, and consequently the stresses on the rigging would increase, meaning the rig would require, on average, some upgrading to deal with those higher stresses.
    Rolling would increase too.
    Comfort aside, the boat would sail and resist capsize better.
    Of course, you can do this to any normal sailboat.
    You can throw money at anything but the same investment in a larger boat would be preferable because you'd get more space and more speed/safety as well all things being equal.
  3. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    You'd need a stronger rig and several other not so obvious upgrades as well.
  4. tranmkp
    Joined: May 2002
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    Location: Texas

    tranmkp "wherever you go. there you are"

    Ok, I think I get it -

  5. Paul Kotzebue

    Paul Kotzebue Previous Member

    The increased roll accelerations of your hypothetical Westsail 32 will be mitigated by the taller rig with more sail area. It is possible the modified boat will have a more comfortable rolling motion with lower roll amplitudes and less roll acceleration.
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