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post #5 of Old 12-30-2008
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At 9.7 beam and 13,500 pounds, it's not going to plane with anything but say 1000 hp of motor (too lazy to do the math), and that's if it's a planing hull shape.
Getting up on a plane is both shape and sheer driving force. At 9.7 it can't carry the sail needed to provide the HP to get it up. At least not and stand up to the wind it takes to get the HP.

Catamaran's manage the extra sail a non-serious racing mono hull (read Volvo quality) simply can't stand up to. My little bitty 33.5 footer carries 780 sq ft, more than a lot of 40 footers and all down low with 14 ft of boom and only 47 off the water in a square top main and screecher on a traveler like track forward, riding on two hulls that are 9:1 length to width, pointy as get out with 4 ft max beam per hull back aft and only draw 18 inches. It's like two lasers with a cross beam.

No need to re-invent the wheel by writing software to show that, it's in many a good book. Try David Kerr, Charles Kanter explains it well but is lazy at math like me.
My D/L is up in the mid 20's depending on what sails I'm flying- you want to plane you have to get to at least that, and still have a flat fat bottom to ride it out on.
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