Subject: Re: [harryproa] kite traction
From: David Howie
Date: 1/28/2006, 6:06 PM

Guess you could attach an iflatable dinghy to a halyard and send it up/along
the mast top hold horizontal till you sorted the kite thing.
IMHO people spend way too much time obssessing over the capsize thing, in
larger than beach type multis it's not really that likely, certainly not from
wind pressure under normal sailing conditions. If you are offshore in serious
shit the waves will be what get ya.
Still it's interesting to follow all the suggestions, and it would definitely
be great if you could right the boat unaided if the worst were to happen, and
the kite with harry on it's side seems as promising as any.
BTW thought that Reynolds 33 someone sent us to was a cool boat too, think it
would beat harry for speed but not accomodation or price.

------ Original Message ------
Received: Sat, 28 Jan 2006 01:39:58 PM MST
From: Mike Crawford <>
Subject: Re: [harryproa] kite traction

<<wouldn't an airtight/watertight spar be enough to keep from turtling?>>

  One would hope.  ;-) 

  Rob once hinted at this in an article a few years back, but I haven't
seen anything since then.  Perhaps someone has done some calculations
along the way.  Once the boat is at 90-100 degrees, there won't be much
heeling moment from the windward hull, but the sail area of the deck
could be an issue, especially if a lot of it is close-weaved mesh or a
solid surface.

  Perhaps a wing-masted schooner rig might have enough buoyancy.  You'd
still have to figure out how to run halyards, though.  Maybe in a
separate sleeve/section?

  Even if the boat does want to keep rotating to turtle, the area of the
sails and the buoyancy of the sealed masts should still give you enough
time to deploy an inflatable righting system.  If you're still in the
boat, of course.

       - Mike

David Howie wrote:

> Wouldn't an airtight/watertight spar be enough to keep from turtling?
> ------ Original Message ------
> Received: Sat, 28 Jan 2006 09:53:45 AM MST
> From: Mike Crawford <>
> To:
> Subject: Re: [harryproa] kite traction
>   That's one of the more unique ideas I've heard.
>   Randy Reynolds claims to be perfecting his system for righting the R33
> cats when they go over, and says he has tested the system four times.
> Many people are waiting for the official unveiling.  It's briefly
> described towards the bottom of .
>   The Firebird catamaran folks sell a compressed gas righting system for
> their 26' catamaran for $4,000, shown on their options page at
> .
>   I'm waiting to see what Randy claims is so wonderful before getting
> serious about a choice, either for a proa or for the current boat.
>   As for the kites, they are one of the few ways I can think of to right
> a boat on on your own.  If you can set up a compressed gas righting
> system to keep the boat from going turtle, then you won't need a large
> kite at all.  If the boat is all the way over, you'll need a lot more
> lift.
>   You could conceivably strap a carbon spar underneath the deck, erect
> it once the boat has turned turtle, stay it to the leeward hull, and fly
> either an outleader or a water-relaunchable traction kite from it.  I'd
> want the spar for two reasons:
>     - Outleaders won't likely want to launch, or relaunch, especially
> when wet, without something that will lift them off the deck/water.
>     - Any kite powerful enough to generate 400Kg of lift will likely be
> too dangerous to handle.  I've spent years traction kiting on land, and
> shudder to think about controlling that kind of force.  It will be safer
> to use a much smaller kite, with a more horizontal force, and use the
> righting moment of a spar to your advantage.
>   The outleader would certainly make sense if you already have it on
> board.   Of course, then you might have to swim to get it.  I'd probably
> have an emergency bag strapped or built into the underside of the deck,
> or along one of the beams, with the necessary kite, lines, cell phone,
> handheld vhf, flares, and so forth.  This is what I'm working on for the
> current catamaran, minus the traction kite, just in case.
>   You might need that spar for righting in any event, even with a
> support boat.  A number of racing and pocket cruising cats can be
> somewhat easily righted by reverse pitchpoling them, but i don't believe
> that a proa will lend itself to going end-over-end.
>   Everything would be easier if there were some sort of inflatable
> righting system to prevent the boat from going all the way over.  Plus,
> even if the boat were to turtle, flotation would still make righting it
> easier.
>        - Mike
> Robert wrote:
> > Looking at the kite boarders I started to think about how much traction
> > a kite has. It would not take a very large kite to lift the lw hull out
> > of the water and back over where it belongs if you were unlucky to be
> > flipped by a wave. For a Harry 12m lw hull it weighs less than 350kg. A
> > couple of powerfoils can generate that much lift, so surely an
> > outleader kite should be able to drag the lw hull up and over.
> > Is my arithmetic correct. I am not sure how easy it would be to turn
> > the boat upside down to try it but It would be an ineresting exercise.
> > It might need a little mast head bouyancy added using the halliards in
> > light airs. The concept could be tried out with a beach cat and a kite
> > from a kite board.
> > Regards,
> > Robert
> >
> >
> >
> >
> >
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