School me on swing rigs

Discussion in 'Sailboats' started by CrunchyFrog, May 1, 2014.

  1. CrunchyFrog
    Joined: Apr 2014
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    CrunchyFrog Junior Member

    When I was about 12 I drew a monohull swing rig concept. Now they are appearing on RC boats such as the Marblehead.

    I understand that one of the benefits is that you can set it perpendicular to the boat and sail downwind with the biggest barn door possible. Is that the only benefit?

    What about a faster boat that sails more on apparent? Would the swing rig help or hinder?
     
  2. Mike Nickerson
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    Mike Nickerson Junior Member

  3. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    Swing Rig

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    A standard rc swing rig can impair pointing ability much as a standard rc jib does by having the projected intersection of the jib luff to windward of the centerline. So called "break-back" swing rigs remedy the situation allowing the whole forward yard to pivot. They've been around since the mid to late 80's down here and in Europe and probably other places.
    I don't see an advantage on a really fast boat like a well designed multihull or mono or multifoiler.
     
  4. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    The Van de Stadt type rigs give up some area and add some weight for the self tending feature. The self tending does not load the sails as much but it continually adjusts and the entire rig at say 80% (this is a guess) of the optimum angle, always. A standard sloop has more sail area, but the rig is in the optimal configuration only for close reaching, and that last 20% can require a lot of work on the sheets.

    So the standard sloop outperforms on a close reach, and to Doug's point, on an extremely fast boat everything is a close reach. But there is a limit to the ability of humans to trim. Richard Jenkins realized this chasing the wind powered land speed record (which he broke). Like I told you before on your previous thread, look up sailbo_t by saildrone. The fastest RC sailboat I can conceive is a wave piercing multihull, with lifting foils and a wing sail trimmed with a wing like sailbo_t but with a two element wing. It is not humanly possible to trim better. Spend your development efforts controlling camber and twist.
     
  5. capt vimes
    Joined: Apr 2009
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    capt vimes Senior Member

    The swing rig is rssentially a free standing, rotating wing mast...
    Eric sponberg has something to say about those type masts here:
    http://www.sponbergyachtdesign.com/StateoftheArt.htm
    I personally prefer the cat ketsch/schooner configuration over the cat rig as de stadt advertises...
     

  6. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    swing rigs

    Graham Bantock* of Sails etc on Swing Rigs-scroll down to #9 Rigs:
    http://www.sailsetc.com/faqs.htm

    *exceptional designer and builder of RC racing sailboats(no multies)
     
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