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Performance Considerations
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Why a Proa? Performance Advantage
Displacement Performance
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Tiny Dancer Mark I Specifications
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Bruce Number Definition: Square root of the sail
area divided by the cube root of the displacement, a power/weight ratio for sailboats.
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Tiny Dancer Mark II Specifications
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| Tiny Dancer Mark I Nov. 1997 | Tiny Dancer Mark II Oct. 1998 | |||||||||||||||||
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Tiny Dancer was conceived as a personal multihull. As such it must be light, and able to be transported on a car's roof rack. It also should be simple and quick to assemble. It needed to be a boat that you would put on your car in the morning and assemble and sail after work. I also felt that the boat design was not worth doing unless it performed well. My definition of performance is high average boatspeeds during a season of sailing and at multiple venues. These requirements resulted in a total bare-boat weight goal of 100lbs.(45.5kg.) for the mkI and 120lbs. (54.5kg.) for the mkII; that includes the assembled boat and spars. The proa configuration was chosen because of its simplicity and therefore I can design it to be light and fast. Tiny Dancer is a Pacific proa, meaning that the rig is to leeward. The boat sails in both directions, each end becoming the bow in turn. The maneuver of swapping ends is called shunting, and one of the considerations of the design is to make shunting easy and stable. The mast is semi-freestanding and steps in a socket in the main hull. This allowed me to avoid the forward beam-dolphin striker assembly used in a catamaran, and since the loads are relatively small in a boat this size, reinforcing in the hull distributes the rig forces into the beams. |
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The hulls were designed with the help of Ted Van Dusen of Composite Engineering. He manufactures world class crew shells, kayaks, and canoes. We used much of his experience with similarly shaped hulls and tank testing at MIT's towing tank to refine the design. The hulls have a fineness ratio of 21.5:1, and according to our data results wave-making at any speed contributed to no more than 5% of hull drag. I first produced a mold for the hulls, using strip-plank technique; cedar over female mold stations. I spent many hours fairing the mold. The hull halves were made in the resulting female mold, and were cured in Composite Engineering’s autoclave. Each hull half weighs 11 lb., and is constructed of carbon fiber over Nomex(R) core. The MarkII uses a rotating carbon fiber wingmast and a square top mainsail. It is a serious, very high performance multihull with performance potential similar to an RC27, or a soft-sail C-class catamaran. We will be evaluating the boat during the next few months and considering a production run. Let me know if this is the sort of personal, high-performance sailboat that you might consider purchasing. The Warren21 MarkII Proa can now be obtained in Kit Form from Composite Engineering in Concord, MA.
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