The Comet 21 was designed as an easy to build, high performance trimaran in a size that is small enough to be manageable yet large enough to carry three adults. The design requirements were established as follows: simple and economical to build using standard plywood boatbuilding techniques, trailerable, beachable, weight not to exceed 1,000 lbs., efficient performance, unsinkable.
Having designed and built various type of boats over the years, we have found that the trimaran has several advantages over more conventional single hull craft including high stability, low resistance, shoal draft, light displacement (no need for ballast), all while still preserving the comfort and practicality of a large center hull. Most importantly the combination of high sail carrying ability and low wave making resistance makes for exhilarating speed potential not found in more conventional types of sailing craft.
The COMET measures in at 21’6” overall length, 16’2” overall beam, 4’9” main hull maximum beam, 11” to 48” draft, 1,550 lbs. displacement (includes crew and gear), 1,000 lbs. empty weight, and 220 square ft. of sail.
The main hull (vaka) is multi-chined with a narrow flat bottom, graceful stem profile, and vertical stern to carry the kick-up rudder. The boat is built of marine plywood over a light spruce frame. The topsides are ¼” (6mm) while the bottom and decks are 3/8” (9mm). The main hull features a small cuddy cabin forward, a storage compartment aft, and a self-bailing center cockpit.
The pontoons (amas) are a V-section type also made of ¼” plywood using the “stitch and glue” method. The cross beams (akas) are a hollow box section made of laminated spruce and fir. Although we are fully aware of and have experience with more sophisticated techniques and materials we are convinced that, along with the extravagant cost of these materials and the toxic working environment they entail, they do not justify (through strength and weight savings) the difficulty level required and thus are not
appropriate for the home builder.
The COMET utilizes a standard Hobie 16 or 18 rig: mast, mainsail, standard rigging. The jib is custom made and mounts on a roller furling unit. The rig is readily available new or used. The Hobie 16 and 18 rigs are efficient and practical and make ideal “power plants” for the COMET.
The plan set (8, 36” x 24” sheets) consists of a Lines drawing with a table of offsets, Construction drawings showing all of the parts, Expanded panel drawing, Daggerboard and Rudder details, Hardware list, Sail plan, and complete materials list. This design represents our concept of a small practical trimaran and builds on our experience designing and building larger craft of this type. To build and sail the COMET 21 is not only to experience the fun of building your own quality boat but also to come to know first-hand the joy of sailing at dazzling speed while sitting comfortably in an enclosed cockpit.