so can the visionary's tack? i assume elementary can since it has no cabin. ditto for any traditional pacific proa like russell brown's. one would just need to arrange for the main sheet to accommodate a load from the opposite side.

would be an interesting exercise to design a full-sized harry that could point well enough to tack. unarig i presume for efficiency. fairings on the beams. i wonder if the accommodations could be kept as spacious.

do you think it would be more difficult to tack from rig-to-lee to rig-to windward, or vice versa, or both the same? i presume gybing is not a problem.

ben

--- In harryproa@yahoogroups.com.au, Rick Willoughby <rickwill@...> wrote:
>
> Ben
> I would defy anyone to tack this boat in any condition without using
> the motor. It has a generous cabin that is hard to push through the
> wind. I doubt that it is possible to maintain enough momentum to
> tack through 120 degrees while keeping speed above 2.5knots. If
> speed drops below that the steering is doubtful. Does not matter
> which way the boat is sailed, getting the cabin through the eye of
> the wind is a challenge. It can be challenging getting it turn
> through the wind with a 60HP outboard in wind over 25kts and a bit of
> joggle.
>
> The other point is that if you want to keep the ww hull to the lee
> all the time in light wind then you must shunt anyhow.
>
> My mind still boggles at how a boat having such a large deck area,
> voluminous cabin and small rig can achieve the speeds it does with
> such little effort. Once you are familiar with shunting it is not
> difficult to get out of what might be tight situations where you
> would need to tack on non-reversing craft. We are not racing the 18m
> proa but there is a bit of traffic and other sailors get a surprise
> when we simply shunt away from their line. Compared to tacking
> shunting is foolproof. Release one sheet and pull up on the other.
> At worse you go back over the ground you have just covered. The art
> is doing it quickly going upwind so you do not lose much ground going
> downwind. When steering I tend toward caution to make certain the
> boat has speed before coming on the wind again to avoid irons. The
> tracks of my shunts are awful when looked at closely. You do not
> need this caution when sailing ww to lee because you can always bear
> away.
>
> The design input from this observation is to be aware of windage and
> how it impacts on the overall performance. It is another factor that
> limits windward performance in particular. I expect that a harryproa
> could be tacked provided the windage was low; the rig was efficient
> and the underwater control surface were also efficient. I have given
> up trying on the 18m.
>
> To tack reliably I expect you would want to have a boat that could
> maintain helm response to maybe 30 degrees off true wind. This means
> efficiency - low frontal windage, high aspect sails and control
> surfaces, rudders well-separated etc.
>
> Rick