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| Slingshot at Weymouth, in 1978. She was 60' x 4'6" hull beam x 42' BOA.She weighed 1800 lbs, plus 4 crew. She's doing about 23kts here. Note spray thrownfrom leeward ama, tucked up against main hull. Her hull lines were flat aft, shewas meant to plane at speed. She's in proa configuration, with all crew on the crossarm,near the pod. Note the extreme forward overhang. It was thought that forward drivefrom the rig would bring her down to her lines. She was built of cold molded wood,using the Gougeon's WEST system. | Slingshot again, this time in trimaran configuration. Her amas were too smallfor her to expect to sail any distance as a true trimaran (note most crew on windwardama); trimaran config was considered an experiment, and was the configuration shewas left on moorings with. She set 700 sq ft of sail. She was not expected to sailfast in light wind, and didn't. |
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| This isCrossbow I, with her original short ama. It was later lengthened to24 ft. Her dimensions were 60' overall (later shortened to 55'), 50' LWL. Main hullbeam 1'10" (giving her a L/B ratio of over 25). She was 28' wide, and weighed1500 lbs, plus crew of 4. She set 850 sq ft of sail in main and jib. Her hulls werecold molded, of 3 plies of 3mm Gaboon. The crew consisted of helmsman, jib sheettender, and two mainsheet tenders; grinder and tailer. She was a bear to sail formany reasons, and it was not uncommon for her winch grinders to be hauling away,right through the speed course. Her best speed was 31.6 kts. In this photo, she isdoing about the same 23 kts as Slingshot above. Note the absence of spray. It wasvirtually a signature of these big Macalpine-Downie boats that they threw hardlyany spray, and never looked like they were trying very hard. Photos and most information courtesy of David Pelly | Crossbow II. This boat shared the same hull length as CB1, but had two, identicallyshaped hulls. I don't have her overall beam, nor all-up weight. She set 1300 sq ftof sail, in the two mains shown. Her leeward hull "lead" the windward oneby 13 ft, in order to give the leeward rig clear air. She was also cold molded, butof two 3 mm plies, to CB1's three plies. The hull shapes had a bit more forward overhangthan CB1, and were a bit fuller aft. Both hulls had rudders, but the port had theonly centerboard, while the starbord had the "planing shoe" visible above.All crew, and all cockpits were in the starboard hull. She had 5 crew; helmsman,3 grinders--cross geared to a single winch, and tailer. The sprit booms were on thewindward side of the sails, and were used to avoid the high weight of full wishbones.The clews were cross-connected, and the boat han only a single sheet. Sails weretwo-ply 12 oz Dacron, and all spars aluminum. The boat had no exotic materials atall, beyond epoxy glue in the hulls. Crossbow's best measured speed was 36.0 kts,in 1980, the last year she sailed. |
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