Rob

You may be interested in an update on the 18m proa down here.

We ordered a perfect day for the first trial sail and were not disappointed.  We had 8 to 15kts with most around 10kts.  Here is the doppler wind image just after I got home:

http://www.rickwill.bigpondhosting.com/wind.png

The 10 to 20kph was close to what we measured on the bay.

Once we got over a few teething issues with rudders and sails we tracked southeast down the eastern shore pretty much on the wind for the south southwest but free enough to keep speed.  The boat is still not bi-directional so this was on a reverse tack with wind coming in from the lee hull.  We then turned west and sailed reasonably close on the wind.  We tacked through about 110 degrees but could make 120 degrees with a single board down doing around 0.8X windspeed.  It may be possible to pinch higher but the hull fouling is a bit of party pooper at this stage.  Some fouling did wear off but it would take a lot more miles to get it clean.  I will be diving before the next sail if I get invited out again.

After tracking west we tacked and ran free to the east.  The big cabin could not be coaxed through the wind under any conditions under sail so we had to start the motor to come about.  I doubt there will be any problem shunting because the boat responds very well to the big under-hull rudders.  On occasion when in irons we would start going backwards so it would have been wonderful if the rudders had full rotation.

This is an image of the track:

http://www.rickwill.bigpondhosting.com/track.jpg

We did not take the boat over land but I did leave the GPS turned on when driving home.  We did 31km at average of about 6kts.  But there was a good deal of fiddling about.  I am reasonably confident that clean hulls would give boatspeed of 1X windspeed with upwind shunts of around 120 degrees made good.

This speed trace helps explain the track a bit more:

http://www.rickwill.bigpondhosting.com/speed.jpg

We managed 17.6kph or say 9.5kts.  This was reaching in about 10 to 12kts true with wind over the lw hull.  The boat felt better however with wind over the ww hull but probably not faster with the amount of fouling.

With the current limitation on sail adjustment I would not want to be out in wind over 15kts.  The boom is still too high to get proper sail set.  There is no way to flatten them.  The linked photo shows the saggy set but this is with halyards hard up and main with a crudely rigged flattening reef.  Sail set is fine for maximum power up to about 15kts.

http://www.rickwill.bigpondhosting.com/sails.jpg

The linked video shows some different views on a couple of points of sailing:

http://www.youtube.com/watch?v=LkZGZTAXwws

Overall it was an enjoyable day and gave plenty of opportunity and ideas for improvement.   

Rick Willoughby

rickwill@bigpond.net.au