<blockquote id=“quote”><font size=“1” face=“Verdana, Arial, Helvetica” id=“quote”>quote:<hr height=“1” noshade id=“quote”>Originally posted by cougar
dick i am on starbaord
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T.S. Cougar !!!
I am too - but am to leeward of you with bow just ahead of yours and coming up.
“TAKE IT UP, PLEASE !” (head to wind will be fine ! tack if you prefer.)[:-pirate]
Back on February 13, Dick Lemke asked me to post a photo comparision to illustrate hydraulic waves on hulls. I went on vacation the next day, which included a stop at LegoLand USA. After seeing the variety of blocks available, dear old dad got the bright idea of making hull plugs from Legos. Naaaaa! Or maybe?
I have selected three examples in which the hulls are heeled about the same angle and the water and the wind conditions were comparable. The top hull is a skinny USOM with a shallow hydraulic aft of max beam; the middle hull is a IOM with a relatively narrow beam, with a deeper hydraulic in the middle of the hull (not the deepest seen); and the bottom hull is a IOM skiff with a very shallow hydraulic far aft.
I have measured and entered values for about 30 one meter designs into my proprietary design program, altered the angle of heel, and noted the angle of pitch. The designs that displaced the same amount of water and had about the same submerged shape when heeled at a variety of angles were, in general, the ones that pitched less and showed smoother water going past their hulls in their photos. These included bothe wide and narrow hulls. The worse ones were the hulls with the biggest changes in the positions of their centers (CF, CB, CLR, CM, etc.)
If you check the web, you will be able to find more dramatic examples of what happens when the bow goes down and the stern comes up, even in relatively flat ater. There are some example that show daylight under the hull between the keel and the rudder, even in relatively flat water.
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