Subject: [harryproa] Re: Robert versus Doug
From: "Robert" <cateran1949@yahoo.co.uk>
Date: 3/18/2009, 6:33 PM
To: harryproa@yahoogroups.com.au
Reply-to:
harryproa@yahoogroups.com.au

Agreed. Windage is the main point rather than weight for driving upwind, and a fast boat is going upwind most of the time.
Going for minimum windage with maximum drive.
Drive depends on righting moment and fore aft stability to avoid loss of flow across the sails.
Righting moment needs a relatively high proportion of the weight in the ww hull. Going for lighter ww hull with the same weight lw hull would not improve the numbers.
Fore aft stability also means less loss of momentum in a slop.
Fore aft stability depends primarily on length, high prismatic coefficient and good bow shape.
So, long skinny hulls with low windage with at least twice as much weight in the ww hull as the lw hull and as much sail as it can handle in a reasonable breeze.
Robert--- In harryproa@yahoogroups.com.au, Doug Haines <doha720@...> wrote:
>
> OK.
> So you're in your harry and I'm in mine. There is a bet for $10,000 over some 1oonm mil course up the Great Barrier Reef say or say the Brisbane to Gladstone.
>  
> You're cruising style but lightened for the race, so no real water or petrol, ....
>  
> I've swapped the ww hull for something with less windage and weight and much less draft.
> So now its winds ranging from some light 8-12 knots at the start, building up to 10-15, and then last half in say 20-25 from who knows what direction.
>  
> My plans give a 41 knot Relative wind speed for flying a harry. Fully loaded.
>  
> Why not even push it without worrying too much about a capsize? there is no stuff to get ruined on the racing boat.
>  
> Doug
>
> --- On Wed, 18/3/09, Robert <cateran1949@...> wrote:
>
>
> From: Robert <cateran1949@...>
> Subject: [harryproa] Re: cantarry - racing
> To: harryproa@yahoogroups.com.au
> Date: Wednesday, 18 March, 2009, 11:57 PM
>
>
>
>
>
>
> -I was looking at the numbers for a 15m/10m 6.7m wide, roughly even in weight distribution when empty at 1.5tonnes but over two to one when loaded down for cruising at 2.5 tonnes. The l/b ratio for the ww hull can be kept to 17:1 and over 20:1 for the lw hull. Set up the rig for handling 25 knots before reefing under cruising weight gives a better set of numbers than a lighter, more even weight distribution set up for handling 25 knots.
> On the other hand, if the lw hull and beams was designed for smaller righting moment, it could be designed much lighter and skinnier.
>
> I don't see an advantage of interchangeable cruising and racing ww hulls as the maximum righting moment is what dictates the weight of the lw hull,
> regards,
> Robert
>
> - In harryproa@yahoogrou ps.com.au, Doug Haines <doha720@ > wrote:
> >
> > I have seen in plans that 45knots of wind will fly a visionarry hull.
> >  
> > Yoyu would still need a hull with seating / short term accomodations, spray protection.
> >  
> > Could be much thinner
> >
> > --- On Wed, 18/3/09, Robert <cateran1949@ ...> wrote:
> >
> >
> > From: Robert <cateran1949@ ...>
> > Subject: [harryproa] Re: cantarry - racing
> > To: harryproa@yahoogrou ps.com.au
> > Date: Wednesday, 18 March, 2009, 10:46 PM
> >
> >
> >
> >
> >
> >
> > -I was looking at the numbers. If the boat is built with a very light ww hull, you don't have such a righting moment for the same weigth lw hull. I I see a racing Harry having about double the weight in the ww hull as in the lw hull and plenty of sail in the lw hull. In fact, a cruising Harry , with minimal weight in the lw hull would be just about optimal, providing the rig was big enough-- In harryproa@yahoogrou ps.com.au, Doug Haines <doha720@ > wrote:
> > >
> > > something like the rapscallion could be nearly classed as a racer to do say freo-bunbury return, bris to glads.
> > > one way or there and back probably no didirect headwinds here anyway.
> > > I found a race suitable for sidecar called the cockburn regatta open to monos mulltis and beach cats, so should be possible, once belong to a yacht club first.
> > >  
> > > East coast - what wouldI get into?
> > > nothing to open ocean too wet.
> > >  
> > > PS going back up to Kalbarru to ontinue on further next week.
> > > Play cricket here in Australia and team made finals.
> > > Plus trying to get Rob to relaunch elementarry to have a sail and shoot soem moe videop.
> > > One rudder was slihghtly needing modyfying and the other one is yet to be put on since it was last out of the water must be a year or so ago. Like to see how ruudder goes too, slightly different to my harriette and different also to chinese rudder I hear.
> > >  
> > > Other day, realized that some people will want certain things differently to others, like the rudders, depending on how you ssail and what places you go. Two major view points could be called cruiser or racer. or a combination. The extra hull to change over for a raace is one of the most exciting points of garryproa. Even on something the size of Visionarry, if the ww hull was demountable .... OK maybe visionarry is a bit solid... but then you would have a big 15m lw hull and mast and sails that would fly around a course easily. Could this be done. Elementarry swapping over hulls can be simple, if your controls, cleats and stuff all finish on the lw side section so only hull and accomodations get removed from the cruiser to be replaced by a small light racing seating or overnight bunks whatever for a race.
> > >  
> > > Your boat doubles as world cruiser and out and out (nearly) short to medium distance racing boat..
> > >  
> > > The bits you would want together in one section is the steering and sheeting controls ie deck. Perhaps the beams are one piece with decks but attach by bolts whatever temporary
> > > way into or onto your seperate hull. That could mean loads of points all the way down the hull where it meets the deck. Then the change over could be a good exercise - keep the cruising hull light in the first place.
> > >  
> > > Doug
> > >
> > >
> > >
> > >
> > > From: jrwells2007 <jrwells2007@ ...>
> > > Subject: [harryproa] Re: cantarry - racing
> > > To: harryproa@yahoogrou ps.com.au
> > > Date: Wednesday, 18 March, 2009, 8:03 PM
> > >
> > >
> > >
> > >
> > >
> > >
> > > At least initially when going for a one-off, the comments on SA seem applicable - handicap multihull A to B races rather than anything around the buoys. It will take the other competitors some time to adjust to shunting when in close quarters. A proa fleet would be another matter - proas short shunting up a shore against the tide !!! just think of the fun that would be !!!!
> > >
> > > --- In harryproa@yahoogrou ps.com.au, Doug Haines <doha720@ > wrote:
> > > >
> > > > Hi,
> > > >  
> > > > After witnessing the charged up atmosphere in Sailing Anarchy forums I got to thinking more about the racing side (being a long term cruiser hopeful), and from what I have seen and tried out with the harriette and elementarry, I would probably investigate a cantarry idea if I was to try and conquer the competition around hee.
> > > > The texel dish boat never came about.
> > > > Who would be looking at competing rather than cruising?
> > > > Or  otherwise something like a big elementarry like the boat harrigami and it's small racing ww hull.
> > > > How do you decide what size limit and what races could you enter.
> > > >  
> > > > Doug
> > >
> >
>

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