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Cat Length question

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Old 11-17-2006, 12:22 PM
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Default Re: Cat Length question

I was told that water is something like 800 times denser than air, so a boat with 2-1/2" of less wetted surface should have a speed advantage in flat water over a longer boat with the same OAL to tunnel length and attack angle/compression ratio.









I think....

Last edited by 9 Lives; 11-17-2006 at 12:28 PM.
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Old 11-17-2006, 12:29 PM
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Default Re: Cat Length question

after reading all your "rocket science" replies, I've concluded that most of you should be more worried about your 2/12' shortages in another place...
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Old 11-17-2006, 12:41 PM
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Default Re: Cat Length question

put it on a tread mill
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Old 11-17-2006, 12:42 PM
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Default Re: Cat Length question

Quote:
Originally Posted by CigDaze
Again, 0.5% differences...maybe.

I'll take it !!

Say the boats are running 100 MPH
Race lasts 1/2 hour
I win by 1/4 mile....
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Old 11-17-2006, 12:45 PM
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Default Re: Cat Length question

thats why a 36 nor tech is 37.8 perfect
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Old 11-17-2006, 12:45 PM
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Default Re: Cat Length question

Quote:
Originally Posted by warbird
after reading all your "rocket science" replies, I've concluded that most of you should be more worried about your 2/12' shortages in another place...
Regardless of one's current stature, the addition of 2.5" is always good.
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Old 11-17-2006, 12:49 PM
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Default Re: Cat Length question

Quote:
Originally Posted by 9 Lives
I was told that water is something like 800 times denser than air, so a boat with 2-1/2" of less wetted surface should have a speed advantage in flat water over a longer boat with the same OAL to tunnel length and attack angle/compression ratio.









I think....
you wouldn't be adding 2.5" of wetted surface though... think of a beak on a fountain... does that really effect the running surface?

and you are right, dry air at sea level is 1/800 the density of water (approx)......
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Old 11-17-2006, 12:50 PM
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Default Re: Cat Length question

Quote:
Originally Posted by customryder
thats why a 36 nor tech is 37.8 perfect
swim platforms don't count...
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Old 11-17-2006, 12:52 PM
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Default Re: Cat Length question

Quote:
Originally Posted by 9 Lives
I'll take it !!

Say the boats are running 100 MPH
Race lasts 1/2 hour
I win by 1/4 mile....
Weeellllll, not exactly.....even if this 2.5" was directly centered on the apparent C.G. (combined C.G. and C.L.), shorter means:
Less aero drag = good
Less aero lift = bad
less direct hydrodynamic surface drag = good
less lift = less dynamic buoyancy = more drag = bad

It's a wash. Net result = approximately zero.

Let's put it this way, those 2.5 inches will amount to whether or not you emptied the change in your pockets.

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Old 11-17-2006, 12:54 PM
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Default Re: Cat Length question

Quote:
Originally Posted by 9 Lives
I'll take it !!

Say the boats are running 100 MPH
Race lasts 1/2 hour
I win by 1/4 mile....
i doubt if percentage of lift directly corresponds to percentage of velocity.... but your right, if you were 0.5% faster you would win by that distance, but just having 0.5% more lift doesn't mean anything by itself... you could have too much lift and have to slow down...
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