Dinghy for people with disabilities

Discussion in 'Boat Design' started by taniwha, Sep 17, 2014.

  1. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    It is tempting to consider a single outrigger.

    It is not a Proa, as the float is used both to windward and to leeward.

    It has to be heavy enough to act as floating ballast and buoyant enough to to not be pushed under on the lee side.

    Such a boat would be relatively inexpensive to build.

    With a single float, the main hull can easily be loaded fro either a dock or from a beach.

    Getting a paraplegic on board might require some kind of hoist or at least an able assistant.

    Another hull form to consider is a scow.

    It can have low sides and a generous rig. Even a crudely built one can perform quite well.

    A self rescuing system can consist of strategically placed flotation, situated so the boat will be easy to re-board from the water, but have enough buoyancy to be bailed out by its crew, once they're back on board.

    Making a boat that won't turtle is easier than making one that can recover from a capsize on its own.

    It would have a masthead float and will flood as it capsizes, so the capsize will be relatively gentle.

    Attached is a design of mine that shows how this can be done.

    The flotation on each side of the boat is less than the weight of the lightest crew member (this is a one man boat).

    The crew member first rights the boat, then pushes one side down, beneath him, then pulls himself on board.

    The buoyancy of his own body does most of the work supporting him, as the boat is half full of water.

    He bails out the boat then continues on.

    For two or three crew, a bigger boat than this will be needed. I'd go maybe a foot wider and maybe a foot longer, with the sides the same height.

    I would also add a mast head float, to keep the boat from turtleing.

    It would have a much larger rig too, to make sure it moved in the expected light breezes.
     

    Attached Files:

  2. SukiSolo
    Joined: Dec 2012
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    Location: Hampshire UK

    SukiSolo Senior Member

    Looks like the Hansa manufacturers have been considering this question too.

    The link below shows a new beach launch trolley. Whilst this would work well launching, recovery might be more of an issue. Just imagining a 4-5 onshore on the South Coast (UK), or on the shingle at Pevensey Bay...;)

    But for sheltered places it might work well.

    http://hansasailing.com/off-the-beach-launching-trolley.html
     
  3. tspeer
    Joined: Feb 2002
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    Location: Port Gamble, Washington, USA

    tspeer Senior Member

    I've been sailing with a good friend of mine who's a paraplegic (almost a quad). Almost any sit-inside boat, like a sailing outrigger or a keel boat, can be used. The problem isn't so much with the boat, but rather with the shore facilities. If you are setting up an adaptive sailing center, I suggest you spend a lot of time considering how to get the people from the dock to the cockpit, and back.

    Perhaps the most general approach would be to crane them in. My friend and I have had a lot of discussions about a gallows-type crane mounted on a pile that would have a swing arm with a track. It would let the crew be picked up from the dock, swung out over the water, and translated outboard to the boat. The crew needs to wear something like a trapeze harness, that could also function as a pfd.

    We've tried using ramps to move him from the dock to the cockpit of a cruising trimaran, and while we succeeded, it was not a very satisfactory approach.

    Another thing to think about is exposure and body temperature control. The same spinal injuries that can render a person unable to walk can also sever the body's ability to sense temperature in the extremities. A paraplegic often needs to be more insulated than an able-bodied sailor, and they need to be able to add or shed layers to maintain their body temperature. The boat may need to provide more protection from spray.

    The change in attitude from tack to tack also needs to be thought out. If they sit on centerline, facing forward, then there's no need to shift position when tacking. But if they sit sideways, that could be an issue or at least an inconvenience. A proa configuration makes a good choice for a paraplegic. They can sit to windward, facing the lee side, and not have to shift position when the boat shunts.

    Finally, there's the issue of grounding. A paraplegic can't jump out of a small craft and push off if they run aground. This may mean that they have to have either a safety crew sail with them, or there needs to be a tender in the area that can pull them off. A centerboard may be preferable to a fixed keel for this reason, although the stability and capsize resistance of the fixed keel is also attractive.
     

  4. taniwha
    Joined: Sep 2003
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    Location: Pattaya, Thailand

    taniwha Senior Member

    Thank you Tom, this is very vsluable information. It seems to point very much towards Richard Woods' design.
     
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