Subject: Re: [harryproa] Re: Aerodynamics and sailing performance
From: "Rob Denney" <>
Date: 3/17/2007, 5:24 AM

Kite photography pretty amazing.  The guy on the mono is in the Transpac next year, will be good to see what gear he has.
where are the double A frame photos?
----- Original Message -----
From: Todd
Sent: Saturday, March 17, 2007 3:45 AM
Subject: [harryproa] Re: Aerodynamics and sailing performance

So what has a more efficient leading edge the foresail on a wire or
the mainsal on a thick wing mast?

I have a rig that would seem to fit a harry style proa the way most
accomadation and sailing are done from the windward hull. If the rig
could be built as light as the rig used now.
Double A frame is also a lifting rig and could be used with solid
wing sail or soft sails. Only thing it would have to have some
standing rigging.

Have a look in the photos double A frame.

--- In, "brag_rotor" <brag_rotor@...>
> Hello Todd,
> Yes, a successful ustayed mast solution is great news - the loss
> of the stays can deliver a disproportionally large reduction in
> but other items then assume greater importance. Remove one
problem to
> reveal the next, as always.
> The 'wire vs foil' illustration is well established; we did do
> at the CAAE in small, crude wind tunnels, but one can play around
> models in a breeze - the effect is that obvious.
> Yes, chord and span play their part - the point is that for the
> sections, the illustration is valid. Everything scales pretty
> if you allow for reynolds Number.
> Not sure I followed your last point about the sails?
> Arguably one of the greatest airfoil designers of the present day
> (I think) trained as a musician - John Roncz. His results speak
> themselves.
> An ounce of experiment is worth a pound of theory in my book.
> All the best, Ben
> --- In, "Todd" <snyder2016@> wrote:
> >
> > I like the idea of an unstayed mast especially on a boat that
> > doesn't need to have gobs of sail area to attain good overall
> >
> > Don't really agree with you on the wire vs foil thingy, may be
> > my misunderstanding. I don't have a formal education in
> > aerodynamics. But doesn't frontal area and cord width play a
part in
> > your apple vs an orange theory ;) I wonder what the out come
> > be with the same size sail for given length masts attach to each
> > would be?
> >
> >
> > Rob,
> >
> > If the whole principal behind your designs are minimal material
> > hardware then why such the high price tag $$$$$ on used boats ?
> >
> > Todd
> >
> > <znip>

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