polynesian Ndrua &/or Double hulled open ocean sailing canoes

 
craneobones
 
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craneobones
Total Posts:  5
Joined  20-12-2013
 
 
 
28 December 2013 17:12
 

I recently found myself reading a lot about the Polynesian style double hulled open ocean sailing canoes.
Being as there many of you much more knowledgable in stability and design , figured I would pose my first question.
In my readings and observations of known replicas, newly built craft and models, I have noticed the overall beam (hull to hull) on these craft to be much narrower than modern multihulls. Proven to be very seaworthy and this narrow
er beam reduces loads, but I can not find information regarding stability… ie capsize potentials vs wider beamed modern craft. Could it be because they have such a low CE/CG?Although I haven’t found info regarding the actual hull depths during a build. Only been able to guesstimate through photo viewing and that is questionable at best.
Any ideas or facts regarding their stability would be nice to know and why or why not.

Thanks

 
 
Editor
 
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Editor
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Joined  28-10-2011
 
 
 
29 December 2013 18:27
 

I’d say you are correct - the low CG, low SA and low CE all contribute to keeping the masts pointed the right way up, though I have not seen any hard data on stability tests. Hokule’a had round bilge hulls and I doubt he was much of a windward machine, so again, this factor reduces the stability requirements.