Small planing hull

Discussion in 'Sailboats' started by grizzly, Nov 21, 2011.

  1. grizzly
    Joined: Nov 2011
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    Location: fresno

    grizzly Junior Member

    Has anyonw ever seen or built a small 8' planing hull sailboat? Just wondering if it is doable or if there are plans out there? I am new to boat building and am trying to understan hull design vs function vs speed and the like. If you took a boat like the optimist and put a bowsprit one it and a jib would it plane, capsize, or would the bow dig in?
  2. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    The Open Bic will plane but I don't think you can build one-but PAR would know of any home-buildable small planing hulls. With enough power a lot of small boats will plane. I grew up with a 9' Dyer Dhow and it would sure plane in 15- 20 knots of wind.

    Pictures- I thought you might find these variations on the Optimist interesting:

    L to R: 1) Optimist fitted with a spinnaker, 2) Optimist fitted with Moth hydrofoils-it actually did foil!, 3) Optimist fitted with solid,2 element wing sail,
    4)Open Bic.

    Attached Files:

  3. MalSmith
    Joined: May 2004
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    Location: Australia

    MalSmith Boat designing looney

    Here in Australia we have an 8' pram bow dinghy called a "Manly Junior" (MJ) which will plane quite nicely with two young kids on board. The sail plan is modest for the length of the boat. Unlike the Optimist, the MJ has a nice flat run aft, which helps.

    In the past we had 6' skiffs with 3 crew and clouds of sail. I believe they could plane if everyone sat on the transom to keep the bow up.

    As well as having hull lines optimised for planing speeds, planing ability depends on having a low displacement to length ratio, so if you can keep the all up weight low enough, your 8' boat will plane. Any boat can be made to plane with enough power, but it more useful if it is controllable. Putting a big rig on small and (relatively) heavy hull is not a way to achieve controllability.
  4. grizzly
    Joined: Nov 2011
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    Location: fresno

    grizzly Junior Member

    I really like the Manly Junior. If I can find good plans I will build one instead of a D5. I dont intend to do alot of rowing so a planing hull would be better than a rowing hull. I am looking at 8' or less boats because in california there is no requirement to regester them. I have a big problem with having to pay taxes on a boat.

  5. WhiteDwarf
    Joined: Jun 2011
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    Location: Sydney

    WhiteDwarf White Dwarf

    8 ft Planing dinghy for adults

    Perhaps you should consider a Firebug,

    I'm 90 kg and get it on the plane regularly above 12 kts. It's strong enough for my weight, I've sailed White Dwarf hard for the last 5 years and she is still going strong.
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