Novice Thoughts on Stability

Discussion in 'Stability' started by Seafra, Aug 28, 2006.

  1. Seafra
    Joined: Aug 2006
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    Location: Upstate NY, US

    Seafra Sailing Nerd

    I'm coming at this as a sailing novice but I'm trying to put together an working concept of true ocean-going stability.

    Would the ideally stable monohull sailboat have a relatively small amount of beam per length(enough to maintain static stability), a steel hull to increase it's displacement, a fiberglass/composite cabin construction to keep the COG low, and a shallow draft twin keel(in a 90 degree split at the beam), tall narrow fuel tank on port, and tall narrow freshwater on starboard. From what I can tell, this should result in a vessel with great dynamic roll stability but relatively poor handling characteristics

    Talking about keels can be like talking about religion I'm sure- but the twin keel seems to offer some good advantages from a cruising aspect though I can't image a racer much appreciating the extra wetted surface. My only hangup is that a twin keel gives me the sense that once a boat has turtled it would contribute to it's inverted stability rather than self right. I very easily could be wrong though.

    Also, could someone please attach a pic of a bilge keel so I can figure out what it is? Is it synonymous with full keel designs?

    More questions to come....
  2. GregW
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    GregW New Member

  3. MikeJohns
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    MikeJohns Senior Member

  4. Seafra
    Joined: Aug 2006
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    Location: Upstate NY, US

    Seafra Sailing Nerd

    Thanks for the articles, guys. Great reading all around.

    Twin keels seem to offer great advantages at the cost of tank time. It seems that anyone could throw on a twin keel system and call it a day- but to have a design that gives you the fluid advantages in relation to hull speed and handling...that's where the art/science hybrid comes in.

    It's interesting how little thought the idea geats on this side of the pond.
    1 person likes this.

  5. knowme
    Joined: Apr 2007
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    Location: India

    knowme Junior Member

    Thanx for the articles. I was wondering if there were any hydrostatics excel sheet available in this forum.
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