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27
Some of you may not know that Jim Betts, the builder of the Sierra 26, is in the process of building a slightly different and markedly less expensive version of the 26,to be called the N/M 27. We have been talking to Bruce Nelson and the folks from Betts about the new boat, and Bruce has given us a bit of a run down on the 26/27. –Enjoy.
Following ACXXX in 2000, Jim Betts approached Nelson/Marek Yacht Design to design a 3 or 4 person one-design keelboat for Windward-Leeward buoy racing on Lake Tahoe as the first priority, and fast planing for max fun when just blasting around for thrills a close second. It was also a requirement that the boat be manageable and easily handled by non-Olympic caliber sailors. Our discussions emphasized the concept of a fast planing boat with exhilerating offwind performance, and the stable, solid feel and speed of an efficient keelboat upwind, without exceeding the loads found on an Etchells for manageability. Symmetrical spinnakers and poles were specified (by Jim) for downwind Vmg efficiency as their local sprit boats (M24's, J80's, etc.) were all deemed as too ineffective on the downwind legs. Definitely a challenging design brief, but conceptually the ideal boat for an old dinghy/keelboat racer like myself - plane offwind like a skiff, power upwind faster than an Etchells. Drawing upon modern skiff design principles, Bethwaite's observations, and my own experience, I developed a low resistance skiff-like hull form with minimum ballast required to achieve the target stability and self-righting capability. Beam, displacement and sail area ratios were adjusted until we achieved (on paper) the sail area-to-wetted surface, displacement and stability values that would produce the target performance and enable planing in breeze as low as 10-12 knots. Our ability to achieve these targets was aided by Jim's desire to apply AC technology to the construction and produce very light, stiff hulls. When completed, I was certain that the design represented the fastest keelboat (for its size) ever. I wish the old OOAK regatta was still in existence so the boat could prove that statement. Vince Brun and I sailed boat #1 when it first came to San Diego. As we left the dock and sheeted the main and jib in about 14 knots of wind, the boat accelerated so fast we almost fell over and Vince's first words were, 'Holy Shiiiit!" As the breeze gusted to around 18 kts that day, we careened about the Bay and re-learned how to sail a fast keelboat. The fact was the boat was so lightning quick that we were not fast enough to sail it well. This led to the first (and only) design modification - I re-designed the bulb to provide more roll damping to help us old guys keep up with the boat. This new bulb went on the boat just before the Hot Rum Series, and we proceeded to easily win class all three races (in light, medium and heavy air) and finish second overall (100+ boats) with a PHRF rating of 66, and an Etchells-like sail inventory of one main, two jibs (light and heavy) and two spinnakers (reacher and runner) - despite breaking our kelp stick one race and slamming into the submerged jetty on another. The new bulb (which suffered only slight damage) made the boat much tamer for us 50-year olds to sail and the boat performed remarkably well upwind and downwind. An A-sail would have helped on the reaches, and this year Tim Lynch (age 52) sailed the boat with an A-sail and swept class in the Hot Rum again - with a PHRF rating of 51! Pretty good for a 26 footer - maybe SA should sponsor a new OOAK regatta! This design has been a fun project to develop, and I've learned a lot about small boat performance from it. The 26/27 is the quickest and most sensitive keelboat around, and the performance is only limited by the efficiencies of the rig, sails and crew. This could be one fun class to develop - I hope Jim finds some success in getting it off the ground in due time. Note that it took the Etchells decades to take off as a class - we're looking to better that schedule. Bruce
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