thanks for the comments rob.

yes, it occurred to me after i posted that the appearance of bow down trim in all the videos could be a false impression due to the bow wave. i will concede that this is probably true. nevertheless i still think a means to shift weight aft when off the wind would be safer or faster, take your pick. your positive comment regarding pantographing leads me to believe you think the same.

a proa will be more bow down than other boats because of the fore-aft symmetry. except for the weight of the rotating boom and sail, and the buoyancy of the bow wave, the COG is necessarily right over the COB on a proa. on any other boat however, the designer could purposely place the COG aft of the COB. i don't know whether this is actually done on monos and cats, but i have been told that farrier tris have excess forward buoyancy in the floats. at rest in flat water the floats just barely skim the surface, and the main hull is shaped for level fore-aft trim. but when rolled sideways by the wind, the float depresses into the water, and the forward buoyancy pitches the bows up.

what would you think of an asymmetric spinnaker tacked to the forward beam where it inserts into the leeward hull, and sheeted to a similar spot aft? on a unarig. that should be good for 90 degrees apparent. the stresses are all still concentrated in the lee hull between the beams. the COE is moved forward so you have less weather helm, which is faster off the wind. the top of the mast is pulled forward, adding more camber to the main, which increases lift and is hence faster off the wind. i'm thinking ocean passages here, not buoy races, so if you have to take it down to gybe, no big deal. just not sure the sheeting angle would work.

and yes, i need to try sailing deeper gybing angles on my weta. wing-on-wing is definitely slow though. tried that when i first got the boat in a 4-boat one-design fleet and lost every time.

i will make sure to point out next time someone exaggerates a harryproa's speed.

ben

--- In harryproa@yahoogroups.com.au, Rob Denney <harryproa@...> wrote:
>
> Interesting thread. Sorry I missed it, but web page writing is all
> consuming, at least for me.
>
> Extracts and comments
>
> "without exception, every single video i have ever seen has shown them
> pitching down. unacceptably unsafe in my opinion. what can be done
> about it?"
>
> I disagree. Very few of them are bow down, none of them to the point
> of being unsafe. For sure, the bluff bows kick up some spray, but
> remove that and they are pretty close to level. Given the low rigs,
> no rocker, easily driven hulls and high prismatics, why would they be
> any more bow down than a multi of similar length in similar
> conditions? Check out the 2 vids at
> http://harryproa.com/index.php/boats/2012-10-11-10-18-30/2012-08-28-18-16-37?start=1
>
> Of course, it can be done. When Elementarry was a schooner with 22
> sqm/240 sq' of sail, I sailed it in 25-30 knots on the Swan River in
> Perth. No swells but frequent large waves from ferries and gin
> palaces. This is windy enough for beach cats to think twice about
> gybing and both crew on Tornados to be perched on the stern downwind
> with the lee deck almost awash. It was possible to push El hard
> enough to pitch pole it, but it was very easy to keep it right on the
> edge using the sheet and steering. The way to tell if you are right
> on the edge is to push it a little harder, which I did and got thrown
> almost a boat length ahead of the boat when it went over.
>
> Pantographing has a lot of potential, just needs someone to realise
> it. Making pivot points for the beams in the ww hull is very simple
> as the loads are relatively small and they are always in the same
> direction.
>
> Spinnakers and kites. Russ uses a spinnaker as a jib/genoa does not
> work beyond about 120 apparent unless it is a ballestron. On a racing
> harry, I would prefer much more upwind sail area (schooner rig and/or
> telescoping) which is not used when it is not needed (too windy, the
> mast bends) and use it downhill. Not as much sail area as a
> spinnaker, but much cheaper, lighter, easier and faster in the light.
> A racing harry would always sail with the breeze at 90 apparent or
> further ahead. Spinnakers are not much good at this angle, you are
> better off with a screecher, but the loads on these are horrendous,
> which adds more weight which has to be carried upwind. A cruiser is
> more likely to run dead square and could probably use a spinnaker in
> light air. Easy enough to fit one, but sheeting angles, extra winches
> and gear make it a hassle.
>
> I have done a few miles with Outleaders. They are indeed great for
> keeping the bows up and with some practice work well. Gybing them on
> a harry would be tricky, but I guess there is no reason why you
> couldn't just move the sheet positions, dump the main and sail with
> the long hull to windward. With a bit of practice they can be flown
> across the sky to increase their apparent wind, while the boat is
> sailing dead down wind. They can also be flown at 90 apparent. I
> tried a 40 sqm one on El and it was pretty impressive for the brief
> times it worked, but the strings were a pain. Built a retrieval line
> which tidied them up, but 4 lines and a tiller were too much for me
> solo. If you try one on the weta, put one string through a block at
> the bow, one from the hounds, and the tip lines at the end of the
> fore beam to keep it stable and eliminate gybes. To trim it, always
> ease the line on the corner that is moving downwards. Try it with the
> boat anchored first. Wear gloves. The thin lines really hurt when
> the kite goes through the power zone.
>
> Beating Hobie 16's downwind. Contrary to popular opinion, not many
> boats are fast enough to sail the angles downwind faster than they can
> blow down almost square running. Maybe run wing and wing with the
> spinnaker during races, and when not racing keep practicing sailing
> the angles by using a telltale on the windward stay to keep the breeze
> at 90 apparent.
>
> Forward rudder downwind. It is very obvious on El that the bow is
> more depressed downwind with the front rudder down. In marginal
> conditions, or racing, I would always have the front rudder up.
>
> "all the accounts i've read of harry proas claim to achieve windspeed
> in the summary, and then later on when they give numbers it's only 3/4
> of it or so. a bit of an exaggeration that's always bothered me."
>
> Please let me know where the above occurs and I will correct it to
> read "are able to sail at windspeed from 5 to 15 knots", which is
> what it usually is. This claim is based on Rare Bird in the first
> video above where (according to Mark Giles, an experienced Aussie
> journo) it is doing 10 knots by gps in 10 knots of breeze in the first
> part and 15 in 15 in the second. And Blind Date sailing at 8 knots
> in 8.1 knots in the fifth photo in the title at
> http://www.zeilenmetvisie.nl
>
> Main sheet fuses are very dangerous as they don't allow for waves.
> Better is a simple fuse that releases when the windward hull lifts.
>
> regards,
>
> rob
>