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 Post subject: Aero dynamics at 65 Mph.
PostPosted: Fri Feb 25, 2005 5:42 pm 
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Site Rank - Captain

Joined: Sun Jul 27, 2003 7:27 am
Posts: 143
Location: New Castle County Delaware, U.S.A
So I was looking at my cat sitting on the trailer the other day and, had a thought. (again I seem to do that often)

The pitch on the tramp looks as if it could produce positave pressure at 65 Mph. (see Bernoulli's principle) thus lifting the trailer.? I dont think my cat will actually "take off" but does it make the trailer feel wierd ?

I've never trailered my cat more than a mile due to no tags but that will be changeing for this summer! Rehobeth bay here I come!

Thanks in advance, Chris

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The Law of flotation was discovered not by the persuit of the law of sinking.


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 Post subject: NO problem.
PostPosted: Sat Feb 26, 2005 10:00 am 
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Joined: Tue May 27, 2003 12:44 pm
Posts: 8979
Location: Oceanside, California
No Problem. I have towed at all kinds of speeds for hundreds / thousands of miles without problem. There must be a pocket of negative pressure behind the vehicle that breaks up the flow over the tramp. By itself at 65... maybe or with strong cross winds maybe, but I have never had a boat or trailer lift. I had a friend who would tow his 16 with just one bunjee over one corner. He figured that the mast secured to the stand and the boat kept the boat solid fore and aft.

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 Post subject:
PostPosted: Sat Feb 26, 2005 10:04 am 
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Site Rank - Old Salt

Joined: Thu Mar 25, 2004 5:39 pm
Posts: 433
Location: West Texas
Last year I was trailering my H16 in very strong cross-winds (30-45mph) and I had to slow way down on the freeway. I was going 50-55mph for several hours and occasionally in gusts I'd see it pick up a teeny bit and skip sideways a few inches. Scared the crap out of me. But aside from that one day, I've never had issues with trailering either. :)

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 Post subject:
PostPosted: Tue Mar 01, 2005 12:21 am 
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Site Rank - Deck Hand

Joined: Mon Aug 25, 2003 2:54 pm
Posts: 23
Location: Durham, NC
When I bought my 17, it came with a low trailer with small wheels.
My hitch was set up for my large trailer with big wheels.

On the way to the first regatta, I look back and the boat is flying two inches above the front cradles.

When I got home, I adjusted the hitch and moved the front crossbar to under the frame.

Since then, I always measure the height of the tramp at the leading and trailing edges.
I make it as level as possible.
Too much lift is just drag.


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