"Point" Foils

Discussion in 'Hydrodynamics and Aerodynamics' started by Doug Lord, Jul 12, 2016.

  1. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    In the quote below Gonzalo Redondo and Martin, publisher of catsailingnews
    refer to 3 and 4 pt foils. I've never heard of foils referred to in that way.
    They were talking about "Z" foils and "L"/ uptip foils: http://www.catsailingnews.com/2016/04/a-cat-applied-tech-new-z-board-racer.html#more

    M- The 4pt Z board is now being adopted in the Nacra 15, surely in the N17, you have designed latest Exploder foils and you have also worked in Americas Cup projects,
    is there a chance to see the 4pt in coming AC for Bermuda?


    GR: No. Rule 11.14 says the windward board cannot be used to increase righting moment. This lack of righting moment is what makes the current 3pt configuration better than the current 4pt configurations. I would emphasise "current".


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  2. sigurd
    Joined: Jun 2004
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    sigurd Pompuous Pangolin

    Is he referring to the stance? IE, off yer rocker: 4 point, broomstick: 3 point, moth: 2 point, monofoil: 1 point.
     
  3. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Maybe. The AC boats, whether they use an "L" ,"Z" or UptiP main foil, all have 4 foils. However, IF a "Z" foil(A Cat) was used the boat would have 4 foils in the water. Boats with an "L" or UptiP foil would have 3 foils in the water.
     
  4. sigurd
    Joined: Jun 2004
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    sigurd Pompuous Pangolin

    A cats are 4 pt because they can't be arsed to pull up the windward one. AC72 are three because they have 2 rudders and one main in the water.
     

  5. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 349, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    "points"

    Martin of catsailingnews confirmed that you are right, Sigurd......
     
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