Ninigret Flare

Discussion in 'Powerboats' started by axeman, Sep 23, 2011.

  1. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    Hey, Im a " 25 type a guy" ! I like small motors and lightweight, seaworthy skiffs. Just make sure that the skiff you choose to build is suitable for a 20hp.
     
  2. Easy Rider
    Joined: Oct 2009
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    Location: NW Washington State USA

    Easy Rider Senior Member

    The displacement hull speed (generally considered to be the top speed of a full disp vessel) is 1.34 X (the square root of the water line length). So the disp speed for an aircraft carrier is close to 50 knots. That's how they go that fast. No amount of power known to man could make them plane. Resistance is, however a combination of skin friction and wave making energy required. Planing hulls are plagued mostly by wave making forces and disp hulls going slow are held back largely by skin friction. Ninigret and Bartender are a planing hulls and have a submersed transom or stern and are plagued by the necessity of causing lots of turbulence (drag) at the stern at slower speeds (12 knots and less roughly). Since you, Axeman want to run at 12 knots (well above hull speed) but not planing your boat will be subject to more wave making resist-
    ance. The force needed to push the water aside as a boat moves fwd is much less w a narrower boat. And the force required to over come the drag of the submersed transom making lots of turbulence aft is far less w a stern like Ketwomoke, Tang or Slipby. So w a narrower boat and a stern that allows the water to return gracefully to the surface is much more efficient. Such a boat can carry considerably more weight in the semi-disp speed mode of about 8 to 12 knots in our group of boats. Ketwomoke pays very little penalty for it's wider beam as long as it's speed is kept down to about 10 knots. You may have the skills to change the shape of the stern of Ketwomoke slightly that would allow her to go about 14 knots w the same power as Tang. Decreasing the curve and angle of the buttock line at the keel should do the trick. I'd consult w PAR or TAD before doing this however. Does this help?
     
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  3. clarksound
    Joined: Nov 2011
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    Location: Charleston, SC

    clarksound New Member

    Ninigret launch and picture

    Also, check out this Ninigret being launched

    http://www.youtube.com/watch?v=b-bqXkKrZOE
     

  4. Easy Rider
    Joined: Oct 2009
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    Location: NW Washington State USA

    Easy Rider Senior Member

    That was a fun video and I'm glad they did'nt fall down w that boat on top of a few people. I see he thought he needed lots of power. It was fun to watch... thanks but I'm sure you wanted Axeman to see it. I hope he will. It's amazing how much of the stern was cut away for the engine. Think of all the fuel one could carry if the engine was mounted on the transom. I'm wondering what Axeman is thinking now or/and doing. He sounded more like a doer than a thinker so I'll bet he's already started building his Ninegret. Hope he posts on builds underway.
     
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