Lcb / Lcg

Discussion in 'Powerboats' started by Mat-C, Apr 27, 2010.

  1. Tad
    Joined: Mar 2002
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    Tad Boat Designer

    Matt... are right as far as you go.......but......

    LCB is just that....the center of a does not define how the volume is actually shaped...

    CP (prismatic coefficient) is the other part of this puzzle......

    Low speed hull.....fine ends and fat middle, low prismatic, forward LCB.

    High speed hull....fuller ends and slimmer middle, high prismatic, aft LCB...

    1 person likes this.

  2. Mat-C
    Joined: May 2007
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    Mat-C Senior Member

    Hmm...well, as always, that makes sense...:)
    But I'm still not sure as to why I keep seeing references to keeping the LCB forward in order improve low speed planing performance... if what I said in my previous post was essentially right....
    In thinking about it, I can see that for a typical v-hull of say constant deadrise, increasing the CP is also likely to move the LCB forward.

    In looking at your article (that you linked to before) you note that there is an ideal CP for each S/L. You go on to give a range for a few S/L's...
    I hate to ask, but is there a graph that show the ideal relationship between these two?
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  1. Mat-C
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