For thousands of years, people of the eastern hemisphere navigated the oceans of the earth using several kinds of ‘rigs’, one of which was misnomered as ‘junk’. Western voyagers developed a different concept and were derisive of the ‘junk’, even though that form sailed much better than their clumsy square rigs. The Chinese had watertight bulkheads, vented rudders, well developed navigation and cartography, and that strange looking, almost organic sail.
My life as a sailmaker began in high performance dinghies and small boats. Then my interest shifted to ocean voyaging and commercial sail, so my sailmaking got big, tough, and heavy. Good fortune and right-place-right-time brought me into windsurfing, where I spent thirty years chasing speed, attaining world speed records of 30 to 50 knots, and winning 12 consecutive world championships in professional windsurfing. We were using the lightest, strongest materials we could put together because the relationship of sail area to displacement is the base rule for going faster.
And through all this work with hand held free-rigs and flexible spars, I was always drawn back to images done in the late 70’s, drawings of a blunt bow junk rig simple cruiser.
A ‘junk’ sail is sheeted from the leech which gives the sailor best control of the leech tension and angle of attack. A ‘junk’ sail also presents a very effective amount of sail area high above the surface where the breeze is more steady and stronger. Having developed the ‘fat head’ profile in 1980 for windsurfing, I understand the importance of that elevated sail area. I feel so strongly about this I will say the top eight to ten feet of a pointed top Marconi mainsail is just about useless and only serves to support the useful area below it, certainly does little aerodynamically.
The ROSIE G weighs 20,000 lbs and is now just on her designed waterline (40’), nearly fully loaded. I think of it as if she was a light fifty footer, but with a bunch of pointy space missing. Similar waterline, less sail area at 850 square feet (we won’t be trying to go 25 knots though). The mast is 100% carbon (except for a layer of Dynel on the outside for toughness) and with running rigging, wires, and the mast head fitting, weighs just over 300 pounds above the deck. The sail is mostly 6.6 oz Hydranet, the top portion 7.7. The battens are mostly 100% carbon and they weigh average 7 pounds each. Total sail weight including the head spar is about 110 pounds, and the aluminum boom adds 35 pounds, but is always only a few feet above the deck.
Our Westsail 42, CORNELIA, weighs 36,000 pounds, and had a main, staysail, jib area of about 900 square feet. We sailed for almost ten years in Hawaii, around Maui where the wind was mostly 8-12 knots and we could easily do 5-6 knots. In the channel with 25 knots of wind, the 275 ft staysil would do 5-6 knots reaching. I’m sure we will be able to easily do the same with the much lighter, cleaner shape of ROSIE G.
By having the travelers for the sheet fully adjustable across the boat we expect to be able to affect the leech trim and the relationship of the trimmed sail to the boat centerline. The idea is to be able to use the low RPM/high torque of electric power to get the boat generating some apparent wind so you can use the lowest RPM possible in concert with the unusual sail trim to make some speed out of very little wind.
There is a fully battened, fat head storm quads’l which can be laced to the mast. It has a functional shape and may be something used when there are strong trades. To me, a storm trysail is a silly shape. Ours is just another WAG.
Or maybe it’s all just a dream?
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