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9 Lives 11-17-2006 11:22 AM

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.... :D

warbird 11-17-2006 11:29 AM

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... :drink:

BY U BOY 11-17-2006 11:41 AM

Re: Cat Length question
 
put it on a tread mill :D

9 Lives 11-17-2006 11:42 AM

Re: Cat Length question
 

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.... :D

customryder 11-17-2006 11:45 AM

Re: Cat Length question
 
thats why a 36 nor tech is 37.8 perfect :D

CigDaze 11-17-2006 11:45 AM

Re: Cat Length question
 

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... :drink:

Regardless of one's current stature, the addition of 2.5" is always good. :drink:

Sean H 11-17-2006 11:49 AM

Re: Cat Length question
 

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.... :D

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

and you are right, dry air at sea level is 1/800 the density of water (approx)......

Sean H 11-17-2006 11:50 AM

Re: Cat Length question
 

Originally Posted by customryder
thats why a 36 nor tech is 37.8 perfect :D

swim platforms don't count... :drink:

CigDaze 11-17-2006 11:52 AM

Re: Cat Length question
 

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.... :D

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.

:D :D

Sean H 11-17-2006 11:54 AM

Re: Cat Length question
 

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.... :D

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... :D


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