I realize this is all theory but I've got nothing better to do right now so....

Let's take two equal boats, both 30 feet long, both 20 feet wide. Both weigh exactly the same, say 3,000 lbs. but it really doesn't matter the amount, as long as they are equal. Now let's pretend they also have the exact same mast, sails, daggerboards, rudders, crew, etc. So everything is "equal" except one is configured as cat, only two hulls, one is a tri, with a middle hull that normally sits in the water, not hovers above the water like a pod-cat.

With me so far? Got that picture in your mind? OK, now let's go sailing.

For our discussion let's say at 10 knots of true wind, the cat fly's a hull. Will the Tri also fly the center hull at the same 10 knots? I don't know. I have always wondered though. Both boats are the same width, both have the same sail area and weight. The mast should be exactly the same distance from each outboard hull on both boats; it's 10 feet from the outside hulls to the center. Now in my little mind, I'm thinking the tri might have a little more righting moment because of the added weight of the center hull being lifted out of the water, but if both craft are of equal weight, that means the cat's hulls have more weight in each hull at 1,500 lbs where as the tri's weight is spread evenly between all three identical hulls, at 1,000 lbs. each. (we said the overall wt. was 3,000 lbs., let's pretend the rig is weightless)

So, to fly the center hull, the tri has both other hulls (2,000lbs) as righting moment, but one is on the centerline so not as much of a moment arm as the single 1,500lbs. of the cat hull. And, why do we see the Open 60 tri's built "square" that is, 60 feet long x 60' wide, while most racing cats beam are only 50% of length? Volvo 40's, at 20' wide and the mega cats are 120' x 60'??

So, all you engineers out there: Which has more righting moment? Which will be "faster" through smooth water? And now for the real food-fight starter: Which one is BETTER?

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