"riverman" wrote in message ...

One problem with your setup in the .png is that there needs to be a
diagonal brace between the canoes: they shift around a lot and you need to
firm up the rig. Also, there is a lot of trimming of the mast that will have
to take place, and in a 'fixed' rig like yours you may be underestimating
the force on the stays, sheets and blocks. Our own rig was difficult to hold
on to with the stiff breeze we had; a strong gale would have necessitated
taking it down quickly, and I don't think your fixed rig could be derigged
fast enough. Also, the bow of the canoes tends to sink down, and in a stiff
breeze the bow wave comes aboard. We could lean or slide our mast forward or
back to dump air or balance the boats, but in your rig, I don't think you
can trim it easily enough.

All that being said, try it out. I think you have FAR too much sail in your
drawing; maybe some sailors here can tell you the formula for hull volume
vs. sail area.

--riverman

I hadn't thought about a diagonal brace, I'd assumed that locking the
crossbeams at each gunwale would be enough of a brace.

I may have got the scale wrong in that image. I'm thinking of a rig
about the size of a mirror dinghy (49 square foot), so about 10' each
for the mast and gaff. A total height of about 16'. The roach (the
part of the sail aft of a line from the tip of the gaff to the tip of
the boom) is a bit big as well. See the new image for a smaller rig.

As for shrouds and a forestay, as long as the 'H' frame at the bow is
stong enough, it'll only be pulling against itself.

If there is a need to lose the rig in a hurry, the gaff halyard can be
lead aft to one of the crew. Release that, and a second later you have
the ultimate reef.

I agree that when running the center of effort is a bit far forward,
so the bows would be pushed down. When you tried it, what would it
have been like without the two in the bows? What would the trim have
been like if it had been just the two of you in the stern?

I am a sailor, but couldn't tell you any sail area to hull volume
ratios.

http://www.beowolf.org.uk/misc/sailing_canoe_2.png