Madness, waterline and Cps

 
toni
 
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toni
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Joined  01-11-2011
 
 
 
02 November 2011 01:27
 

Hi Guys.

I was very impressed by the new video of Madness, sailing, I presume in the Chesapeake or close to Charleston.
It is a beautiful boat, very atractive lines, great finish. John really excelled with this one!.
One comment for the the gang….I noticed when chop became a little uncomfortable, that Madness tended to hobby horse a little….and Sven this goes probably more to you than anybody else…
Does PB tend to do the same? Under what RANGE of conditions? Do you all feel that a higher Cp would help the motion? Also, do you carry any loads close to your bows/sterns? Do you feel that a recessed forestay attch. would help the motion?
cheers
toni

 
phillipking
 
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phillipking
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02 November 2011 02:22
 

Hi Toni,

I think the short burst of pitching was caused by a very short period passing power boat wake.

I’m not sure any small boat is immune from that.

Regards.

 
phillipking
 
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phillipking
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02 November 2011 02:55
 

Sailnet forum has a description of ” madness” test sail by the crew. Here….http://www.sailnet.com/forums/general-discussion-sailing-related/80274-test-sailing-pacific-proa.html

Regards

 
James
 
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James
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02 November 2011 03:31
 

Thanks for the sailnet link, Phillip. Here’s an interesting quote from one of the commenters-

I built a 24’ tacking outrigger canoe last year and sail it regularly. It doesn’t shunt like a proa, but next year I’m going to refit it as a shunter to experiment with this a little bit. Here’s a little video to show what it feels like ama to lee. Ama to windward is much faster and you feel that the boat is just not straining nearly as much, doesn’t have to punch through the waves and swells nearly as much. IMHO a far superior ride.

cheers, James

 
skyl4rk
 
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skyl4rk
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02 November 2011 04:02
 

I had trouble with the video link posted at Sailnet, but I think it is this video:

http://www.youtube.com/watch?v=V6V-uExqn04

 
James
 
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James
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02 November 2011 04:14
 

Many thanks, Paul 😊

 
toni
 
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toni
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02 November 2011 04:23
 
phillipking - 02 November 2011 02:22 AM

Hi Toni,

I think the short burst of pitching was caused by a very short period passing power boat wake.

I’m not sure any small boat is immune from that.

Regards.

Hi Phillip

Yes that would definetely explained the motion, and I agree with you all boats mostly the small ones (all of them for that matter) would hobbie horse under certain conditions. I just open this question, to get some feed back regarding Cp, WL etc. Naturally the answers are well known and documented for any other kind of craft including multihulls, of every type BUT THE PACIFIC PRAO!....do we really know or is there any camparative data regarding effect of higher Cps againts lower related say to LWL/BWL ratios, Froude numbers etc.?
I am not aware of any.  Does anybody know?

cheers