Twin Rudders vs Twin Keels

Discussion in 'Boat Design' started by mimmosan, Sep 19, 2003.

  1. mimmosan
    Joined: Sep 2003
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    Location: NYC

    mimmosan New Member

    I've seen a Dutch design of a steel sloop with twin rudders used to dry out the boat when the tide goes out. The design seemed interesting to me since I plan to live aboard and sail shorthanded most of the time. The appeal was obviously the ability to stop somewhere and not worry as much on where tide was etc.

    What would be some of the shortcomings of this design?
    Would it work on a fiberglass hull and can it be retrofitted to an existing boat?
    Am I better off with twin keels?

    Thank you for the advice.............
  2. dionysis
    Joined: Jan 2003
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    Location: Tasmania, Australia

    dionysis Senior Member

    Big question.

    Putting twin rudders on an existing boat, may be dangerous, depending on how far forward the keel is. You dont want the boat to tip forward. The rudders would have to be as deep as the keel and very strong = thick, and this may be detrimental to performance.

    Twinkeels are a good way to go if you want the boat to stand upright.

    Retrofilling these to a steel boat would be pretty straighforward, but to a fibreglass boat would be a real big job.

    Hop this helps
  3. Tom_McGuinness
    Joined: Sep 2003
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    Tom_McGuinness Junior Member

    An old friend of mine had a boat like that which he regularly sailed between NL and UK. From what I remember, it tended to exhibit a little bit of a Dutch Roll....a coupled roll/yaw motion.....while underway.

    My friend was a very experienced sailor and chose to accept it's handling characteristics so that he could beach it on the mud flats, if need be, of which there are many along the North Sea coasts of the UK and NL. It also provided good access for cleaning, inspection and repair.


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