Adding sail and maintaining the CE balance

Discussion in 'Sailboats' started by ecflyer, Sep 8, 2009.

  1. ecflyer
    Joined: Jan 2009
    Posts: 81
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    Location: Green Bay, Wisconsin

    ecflyer Junior Member

    I have a 46'-9" ketch sailboat that I would like to improve the sail area to increase performance in light airs. If I were to add 2.0' to the foot of the head sail via bowsprit and 4.0' to the foot of the mizzen, would I be maintaining the balance of the CE to center of lateral plane. I am unable to change the main. Additionally, would changing from a 130% genoa to a 150% change the helm balance, because I notice architects only use 100% of the foretriangle in calculating the CE. The current sail area is quite low at about 800 to 850 sqr ft. Thanks for your help.
     
  2. catsketcher
    Joined: Mar 2006
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    Location: Australia

    catsketcher Senior Member

    Low aspect may not be the way

    Gday

    The potential fixes you have mentioned seem reasonably expensive. The rigging of a bowsprit and new forestay, furler section and then increasing the mizzen boom length and buying a new mizzen sounds pretty pricey. My prediction is that it would not do much for your upwind light air performance.

    This is because you are decreasing the aspect ratio of the rig. I would recommend you do the opposite. You can increase the aspect ratio (in a way) of the mainsail you have by increasing the roach and going fully battened. Look at Steve Dashew's Ocean cruising encyclopeadia a few examples of this. If you could put in a triatic stay or similar for the main mast you may be able to dramatically increase mainsail area. A roached planform is more efficient and a new main may prove to be a better investment than the other changes mooted.

    cheers

    Phil
     
  3. ecflyer
    Joined: Jan 2009
    Posts: 81
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    Location: Green Bay, Wisconsin

    ecflyer Junior Member

    No changes are needed because this is a new build. I was already planning on fully battened main with roach.
     

  4. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

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