Mast location

Discussion in 'Multihulls' started by lwalker, Jun 6, 2009.

  1. lwalker
    Joined: Jun 2009
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    Location: Minnesota, USA

    lwalker New Member

    I haven't seen this question raised here before so I hope it doesn't seem too dumb: is there a problem with putting the mast for an outrigger sailing canoe on the aka instead of in the canoe itself?

    I have a poly 14' canoe I'd like to try sailing. If I add a single outrigger, then I either need to sail it like a shunting proa (inconvenient), or hike out when the ama is to windward to control the roll. It seems logical that if I step the mast somewhere on the aka, then I can take advantage of the buoyancy of either the main hull or the ama to limit the heeling and therefore how much I need to shift my weight. i.e., it behaves more like a catamaran.

    However, since I've never seen this done before, I may be missing some obvious problem. Am I?

    -lyndon
     
  2. TeddyDiver
    Joined: Dec 2007
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    TeddyDiver Gollywobbler

    It might work quite well actually. Some thing to consider thou.. Placing the mast somewhat closer to main hull, canoe, than the ama will give more balanced sailing characteristics with opposing tacks. How much depends of the resistance, bouyancy and weight differences of the hulls and are trade offs in some respect..
     
  3. yipster
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    yipster designer

  4. bill broome
    Joined: Jul 2008
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    bill broome Senior Member

    an asymmetrical catamaran has endless problems built-in. but there's no reason why you shouldn't try putting the mast on the aya.

    you can find the point on the aya where the drag is equal by towing it with weights representing crew and mast in place. a fair bit of trial and error involved, but quicker than moving the mast i would guess.

    they use amas on both sides in the philipines and indonesia, there's a good reason for that...
     
  5. peterAustralia
    Joined: Mar 2006
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    peterAustralia Senior Member

    The craft you refer to is generally called a tacking outrigger.

    The best place to talk about such craft is at the yahoo group proafile, link is here http://groups.yahoo.com/group/proa_file/

    Tacking outriggers are actually fairly common in the oceans. They did exist and still exist from Madagascar to India to New Caledonia to Indonesia to Samoa. I have one, Peter Mirow has one and is building another, Dave Pont has one, Gary Deirking built one and has plans for one, and there are more out there that I can think of right now. 2 French brothers crossed the Atlantic in a 20ft tacking outrigger about 4 years ago now. There is also the Raptor 16 by Hydrovisions.

    Putting the mast on the outrigger. Well I guess you could if you wanted to. Not too sure what the advantages would be. Most I have seen have a vertical mast, and cant see many differences in performance varying on where it is placed.

    My outrigger is heavy and never feels as though it is going to tip. I do not have much sail area it is true. If you wish to hike out onto the crossbeams whilst the outrigger is working as a counterweight, then that ought be OK. One option is water ballast in the outrigger, add another 20kg out there using a bucket and you have a large increase in righting moment.

    N Peter Evans
    tacking-outrigger.com
     

  6. lwalker
    Joined: Jun 2009
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    Location: Minnesota, USA

    lwalker New Member

    The original reason was to avoid shunting while using a light, buoyant ama that wouldn't work as ballast. However, I've been able to find the google search term that turns up enough hits and it doesn't look like shunting is as bad as I thought.

    yipster: thanks for the link to that pdf, it really helped me learn about alternate designs.
     
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