Subject: [harryproa] Re: mast bouyancy
From: "proaconstrictor" <proaconstrictor@yahoo.ca>
Date: 2/10/2006, 4:19 PM
To: harryproa@yahoogroups.com.au
Reply-to:
harryproa@yahoogroups.com.au

--- In harryproa@yahoogroups.com.au, "Robert" <cateran1949@y...>
wrote:
>
> Did some rough calculations on the Harryproas stability at 90
degrees.
> Empty, a Harry is stable on its side but not by a large margin.
> Probably the resistance of the masts as well as the bouyancy would
stop
> it turning over. Loaded, IFF the loads are well placed the
situation
> improves. An extra 40kg or so bouyancy at the masthead and there is
big
> improvement. Possibly soft urethane foam sewn ito the top panel of
the
> sail would do. With wing masts the margin is much larger.
> Regards
> Robert
>

I just don't see the point.  The HP is the most stable multihull
design in existence relative to the direction of capsize here
described.  Because of it's assymetrical design.  Why concern oneself
with a leeward capsize to the spar hull.  The only real issue is a
capsize to the accomodation hull that appears difficult, but if it
happens you are well out of luck with any mast floatation I can
contemplate.

The problem with this kind of design is it attracts a lot of
technical exuberance, which is a good thing, as long as one doesn't
loose track of the fundamentals.





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