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Alternative
Race Boat Design,.....around the world First I must say that I'm really surprised at the lack of participation in these forum columns provided on this RACE site. With the race nearing completion I thought I would post something controversial and see what reactions arise. Why are these boats sailing around the world, in a predominately downwind race (at least 80% downwind), using a fractional rigged Bermudian sail plan?? I know as a result of their speed that they pull their apparent wind quite forward, and even to a beating angle at times, at which point they should be bearing offwind more. But I question the use of an upwind sailing rig in these broad reaching (from true wind) conditions; and particularly a rig with a very big, hi-aspect ratio mainsail. This huge mainsail is a culprit in downwind sailing. Not only is it a monster to handle in heavy air, but it develops a shape and a huge force that drives the bows of the boat under. This is the sail that's so hard to raise and lower off the wind, that requires many extra crew, and that must be built extra stout (and heavy) to handle the huge loads impressed on it, and its headboard & halyard as it is reefed and unreefed. And this is the sail that's always breaking its battens in compression at their forward ends, or as they flex in flogging, or bend backwards when pressed over the shroud/backstay. With a wing mast at its leading edge this full-battened, beautiful airfoil shaped main is a wonderful upwind sail, but downwind, watch out!! And then to only utilize a fractional jib?? Offwind should be powered by a forward-driving, lifting, masthead-hoisted, headsails (jib, genoa, reacher, etc.). I've noted in a number of instances during this race, that when the various boats got into heavy conditions, most put at least 3 reefs in the mainsail (or doused it) and raised the solent jib (sometimes hoisting it slightly higher). The use of only fractional headsails has been dictated by the rotating wingmast/mainsail/staying combination. Lower aspect-ratio sails can actually provide more efficient drive in a reaching situation, and they contribute significantly less overturning moments and bow burying forces. Twenty five years ago I proposed a rig with its mast stepped aft at approx. 2/3 the length of the boat and its top raked forward. The rig carried no mainsail , but rather two headsails, ala a cutter, and a mizzen for balance; lets say a marriage between a cutter and a ketch without a mainsail. In my updated description, "Revisiting a Mast-Aft Sailing Rig", I refer to it as a single- masted ketch. The traditional mainsail is replaced by my inner"mainstaysail". What a wonderful reaching rig!!....lower aspect ratio, lower center of effort, more manageable size sails, and all sails could be roller furled. Could we adapt this rig to a downwind racing catamaran?? I would propose the following. There is now no need to rest the base of the mast (aft rig) on the front crossbeam, so lets look at alternative crossbeam arrangements. Wouldn't this very beamy cat be much stronger and more rigid if the crossbeams were configured in a "X" arrangement? Their angled attachment at the hull ends would likely prove superior in strength to the 90 degree arrangement, and most importantly, the cantilevered length of these highly stressed beams would be half that of a conventional arrangement. Very often one forgets the huge downward compression loads exerted on the front crossbeam by the towering wingmast and its rigging pulling at the mast like an arrow in a cocked bow; and this is intensified hugely as the boats pounds thru a sea; and all the while this beam must hold the boat together. It should prove interesting to closely inspect Club Med and Innovation Explorer in light of the front beam problems of Team Adventure.(* see note) My forward raked mast exerts quite a bit of compression to its own aft bulkhead, so lets modify things a bit for the racing version....split the mast into an "A" arrangement and mount the two bases into each hull at the point of attachment of the rear "X" crossbeam(s). We've triangulated everything...much stronger for its weight. And we may have even simplified the spreader/rigging arrangements. What do we have?.....partial list: Shorter rig height....less pitching momentum....less overturning forces....more manageable size sails....multiple rollerfurlers could almost eliminate any hoisting of sails...no broken battens and less chaff....no batten cars or jammed mainsail slides ....no massive booms(gybes!!)....no traveler cars, etc....no mast compression loads to crossbeams....smaller crew size and provisioning....slimmer, less buoyant bows required (less pounding upwind)....less daggerboard area required (shorter, stronger, asymmetrical?)....more rigid hull/beam structure...less interference between old front mainbeam and the ocean....tramp areas divided up smaller....central pod 'living' area incorporated into intersection of "X" beam, and/or entrances to hulls behind aft crossbeam connection....potentially lighter boat with greater drive per square foot of sail area....etc... I intend on posting some sketches of what this race boat version might look like in the near future. Keep a watch. If you really can't wait and/or you're interested in participating in a 40' prototype, contact us directly. INTERESTED?? Now's the time to start prototyping for the next "RACE", Year 2004 Bruno Peyron's premier sailing event, "THE RACE", appears to have captured the imagination of many sailors around the world, particularly with the outstanding record time now set as the new benchmark. Yes, it does appear as though there will be a continuation of this RACE concept. Talk is of a four-year cycle, 2004, 2008, 2012… There is a growing list of around-the-world races; The RACE, the Jules Verne, the Millennium, the Vendee Globe, and the Volvo/Whitbread. Some, or all may survive, but you can bet they're all more exciting than an America's Cup. Bruno has also introduced another new event called "Voiles de Future", a week long series of speed trails and races whose purpose is to unite all classes with the same 'spirit' as the boats in The Race; i.e., built to Open design rules and primarily for speed. This combined with other event racing of Open class multihulls and Open class monohulls is providing a venue for the development of marvelous innovation in sailboat design and full-scale prototyping in a real world environment. The RACE has now provided that venue for this new class of Super Cats. The next RACE should prove even more exciting!! I
don't think you could say anything like that about the next America's
Cup. They will spend 4 to 10 times the money to go a fractional
knot faster, and to sit in protest rooms or court rooms for hours
or days after each race; grown men arguing over trivial technicalities
rather than advancing the state of art of sailing. Shame. The very
reason I stopped following this competition years ago. Boring! * Note: 4/20/2001. As we now know "Club Med" and "Innovation Explorer" both experienced structural problems with their front crossbeams. Details are not fully known, but the majority of problems seemed to have occurred at the connection points between the crossbeams and the hulls, and there it appears to involve considerable delaminations between the hi-tech fiber skins and their sandwich cores. **
Note: 5/20/2001.
A variety of damage reports continue to filter in, even though there
has been a concerted effort to keep them undercover. It now appears
as though the damage to Club Med is quiet serious, " Club Med
was in a much worse state than many people realized when she made
her triumphant arrival in Marseilles. Had this damage occurred earlier
in the race, Danby is certain they would have been forced to make
a stop over." There are numerous reports of shear failures
between the skins and core at the crossbeam connections, on both
sides of the boat, and collapses of the core materials of the hulls
in the areas of the daggerboards forward of the front mainbeam.
The waves had also destroyed the 'bomb bay doors' in the bottom
of the mainbeam where one of the liferafts used to be stored. This
naturally raises some concerns about her two sisterships built to
the same specifications. |
