Calico is a small scratch built sailing dinghy. She’s not a very revolutionary boat by the look of her hull; in fact the hull is based on a design that is over 30 years old. Her rig however is right at the cutting edge of technology. Calico was deigned as a test bed for new rig technology, her sail and carbon mast were specially built for the boat.
Hull
Calico’s hull is built from lightweight fiberglass and carbon fiber reinforcement; her hull is 8’7” and 3’ wide. Her hull is wide, very wide for the boat size with soft chines and a flat dish-like bottom so she can plane easily. Building the hull took about a week. After that the daggerboard trunk and single thwart were added. There are no raised interior seats in this boat, all of the space is right on the single skin bottom. Since there is not really room in this boat for them, you sit on the floor and to windward of the lower mast step slide rail. The thwart is used as a line control center: 1 main sheet, 1 downhaul, port mast cant, starboard mast cant, forward mast tilt, aft mast tilt, 2 traveler lines, and the port and starboard mast cant safety stops. The whole hull is a single skin laminate with a foam-cored deck and transom making the whole structure about 40 lbs.
Rig Design
Calico’s rig consists of a single 5.4 m2 elliptical windsurfer sail and a 19’ carbon fiber mast. This sail allows the boat to sail in very light winds, and by light I mean from 3 to 4 knots up to about 15-20 knots if you really wanted to push your luck. The mast is able to cant 35 degrees to either side of vertical, allowing the sailor to increase or decrease the apparent sail area. When you sail upwind the mast can be canted to windward up to 35 degrees. Canting the mast increases the sail area by as much as 25% this allows the boat to carry a smaller sail or in the case of Calico; sail in much lighter winds. The cant mast also has the advantage of reducing drag on the hull, because it tends to lift the boat out of the water, instead of force it down like a normal mast and sail.
Conclusions
As of this writing Calico is still under construction, I hope to have her finished and ready for launch in early February 2003. Calico was presented here as an example of cant mast technology. I will post an update as soon as she is launched and sea trialed, with the predicted vs. actual figures for weight, speed, displacement and all of the other fun calculations.