<<And I wish you would stop being so darn reasonable.. I had
ruled this sail out a year ago and now you have me seriously
considering it again!>>
Ha! :-)
You know, I think that's the whole point of this group in the
first place. Not about rebelling, but questioning orthodoxy, even
our own.
Sailors are a funny crowd. They have to be right. Real men only
sail wooden ships with beautiful lines and inefficient-but-beautiful
sails. Real men only sail fast monohulls with fragile fin keels and
difficult-to-handle high tech stayed rigs. Real men only sail
multihulls, and would never be caught in a lead mine. And so on.
So the proas get a weird rap, just by virtue of their being
different. Even the multihullers, who have made the choice to
eschew monohulls, insist that trimarans or catamarans are the way to
go.
In the end, the harryrproa is mostly about the most efficient,
fastest, lightest, most seaworthy boat that can be made for $X.
Many would argue that the harryrproas are superior regardless of
cost, but since the cost matters to me, it's part of the equation.
So why not use the same criteria for a hull shape or one's rig?
That's where even this group, myself included, starts to fall into
orthodoxy. You have to have a semi-circular hull shape because
that's the minimum wetted surface area. You have to have a rotating
mast, hopefully a wing mast, with a fully-battened squaretop main
made from high-tech materials that can hndle the stress.
Do we?
Rick's calculations challenge the previous notions of hull shape,
and this goes beyond the realm of subjective opinion into the realm
of proof in terms of flow calculations and actual hull performance.
If we can get something that sails faster, with better leeway
resistance, an easier build (well, in some materials, at least), and
is potentially more seaworthy, why not make the leap?
The Wharram soft wingsail, and Swing-Wing slightly less soft wing
sail, challenge traditional notions of what high-performance sails
should be. Both are low-tech ancient sails in some ways, but if
they can fit the criteria, why not make the leap?
Of course, there are good reasons to not make the leap. Maybe you
want a schooner una rig for various reasons, or you want to build
your 50'-er out of a semicircular bent panel for lightness and
quickness of build. Such is life.
But if something is faster, easier, simpler, and less expensive,
I've got to take a look. I'd be a hypocrite to tout the proa's
advantages and ignore the benefits of soft wingsails and alternative
hull shapes.
And since I can't yet contribute actual design ideas to the group,
I'm forced to work on being reasonable. I don't care if we all
agree, but I think it's useful for the discussion to lead somewhere
beyond one idea versus another.
Note of admission: I didn't want to like the swing-wing. But now
I have no choice.
<<I thought that I had seen you post a message that you were
going to try out JavaFoil>>
That wasn't me. I'm currently designing our new house, a new hut
for our island property, a house for a friend, and building a 26'
power dory based on a 27 hp yanmar diesel outboard. Plus renovating
a 23' Pearson Ensign for easy/safe daysailing with my wife and young
daughter (10' long ultra-deep cockpit, self-righting, positive
flotation), and putting the finishing touches on our Stiletto
catamaran renovation.
As a result, I'm tapped out in terms of free time. Working on my
"next boat" proa design, along with all the software that will
entail, will probably have to wait a few years.
- Mike
Gardner Pomper wrote:
Mike,
I thought that I had seen you post a message that you were going to try out JavaFoil. Did I remember that right? It would seem that is what this discussion needs; some actual numbers comparing the lift of a softwing sail in this configuration to a "normal" sail. From looking at the photos, it would seem it would be worth approximating the shape as a solid wing, with a thickness of half the frame.
And I wish you would stop being so darn reasonable.. I had ruled this sail out a year ago and now you have me seriously considering it again! <grin>
- Gardner