AC 36 Foiling Monohulls

Discussion in 'Sailboats' started by OzFred, Sep 13, 2017.

  1. TANSL
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    TANSL Senior Member

    Great. It seems to me a very compact design, well achieved, which will surely provide very fun navigations. My congratulations for this and other designs of your portfolio.
     
  2. Doug Lord
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    Doug Lord Flight Ready

    Very interesting-welcome to the forum! Seems like lite air wetted surface might be high though maybe the crew could heel the boat like smaller scows?
     
  3. TANSL
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    TANSL Senior Member

    Although the boat is heeled, the wet surface will be very similar to when the boat is upright. Like any other foil, before "flying" you will need to maneuver to get enough speed.
     
  4. user63137

    user63137 Previous Member

    Thanks Doug. The idea is sail in foiling condition always, try to generate lift as fast as possible. This hull in heeling condition behaves like a catamaran, keeping the length water line and a wetted surface with good Length/Beam ratio.
     
  5. TANSL
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    TANSL Senior Member

    I regret not agreeing but, in my opinion, the Length / Beam ratio does not say much in relation to the wet surface of a hull.
     
  6. OzFred
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    OzFred Senior Member

    The crew can cross in front of the wing too, they do in skiffs. Not so much on multihulls though as there's usually no deck or tramp in front of the mast.

    I think your concept is close but also the boat will be a challenge to sail fast when not foiling. It will be an interesting trade–off between foiling and displacement. They can't heel too much to reduce wetted surface or the load on the leeward foil will be too high. Staying flat means better lift but also more stickiness.
     
  7. user63137

    user63137 Previous Member

    Yes
    I did this concept trying to keep the catamaran idea , the sail-wing , the foils , the moments, without ballast,etc . I agree with you , I hope a design that can sail fast when not foiling. The design of my hull assume that the sections can not have inflections, but being able to foil easily and do a exciting typical match race start with the hull on the water.
     
  8. Konstanty
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    Konstanty Junior Member

    The problem is the lack of the possibility of reefing the main sail.
     
  9. TANSL
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    TANSL Senior Member

    Sorry, Agustín, I had thought it was a 5 or 6 meter boat and the idea seemed interesting and fun. For a boat of about 28 m, as it seems to be this one, the idea of mono hull imo has no advantage over the multihulls.
     
  10. Konstanty
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    Konstanty Junior Member

    With stepped hull and canting keel for safety shoud be OK.
     
  11. TANSL
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    TANSL Senior Member

    You may be right but I do not see the need of stepped hull nor to combine canting keel and foils for a "flying" boat. Anyway, when the ship "flies" perhaps such a wide hull can be an inconvenience (added weight, strange effects with the wind, ...)
     
  12. user63137

    user63137 Previous Member

    Yes , I know ,a mono hull has no advantage over the multihulls . With respect to the stepped hull , to make it work ,the boat need sail in the plane range, not foiling. And the canting keel I think that not is safety in a match race.
     
  13. Konstanty
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    Konstanty Junior Member

    Weight canting keel is not a waste. This has a greater torque arm than the crew on the windward broadside.
     
    Last edited: Nov 8, 2017
  14. user63137

    user63137 Previous Member

    The idea is use the rudder foil of windward too
     

  15. Konstanty
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    Konstanty Junior Member

    OK. Rudder foil +windward + canting keel = more righting moment and more speed and savety for storm weather.
     
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