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Open Class 50

1998 April 12

Singlehanded Racer

Bill Cook took a hull designed by Rejean Desgagnes of Quebec and finished the design for Chris Beirne's entry into the Around Alone race, formerly known as the BOC. The boat is typical of the breed in that it is a big, dinghylike hull with ultralight displacement and exaggerated beam, twin rudders and water ballast. The rig is huge, draft is 12.5 feet and the boat appears capable of extremely high speeds in the hands of the right sailor.

In the words of Arlo Guthrie, ÒBut, that's not what I came to talk about.Ó Ray Thayer's Brewer-designed Around Alone boat Wild Thing just sank off the Washington coast. Ted Brewer and Ray Thayer worked hard together to produce a very different Around Alone-type boatÑheavier and more moderate in its proportions. The 60-footer was doing double-duty as a cruising yacht. Mr. Thayer, through truly heroic efforts, managed to save himself but lost his boat. Reports indicate the boat was close reaching in 30 knots of wind under double-reefed mainsail and blade jib. There was about 4 tons of water ballast in the weather-side tanks. A 50-knot puff hit, rounding the boat up to weather. The rudder went hard over to counteract the round-up and the rudder blade stalled.

The boat went head to wind and then tacked itself, leaving the jib sheeted to weather and the 4 tons of water ballast now on the leeward side. The boat heeled to about 105 degrees. Basically, water poured in through the open Dorades (added by the owner) and swamped the boat, which quickly foundered. The downside (no pun intended) of water-ballasted boats needs to be pondered.

I look at this Cook-Desgagnes design-with its wide beam, 13,500 pounds of displacement (D/L 48.24) and lead ballast of 3,300 pounds-and I wonder why the same catastrophe could not happen to this boat. The two areas to consider are the skill of the crew-and when the crew is one person, you have to include a heavy factor for fatigue and lapses in judgment due to fatigueÑand the stability characteristics of the boat. We could also open the Pandora's box of the ability of autopilots to steer in severe conditions.

The problem with almost all stability calculations is that they cannot reproduce the dynamics of wind and waves and their effects on the heeled boat. This preoccupation with limits of positive stability is, in most cases, a paper chase by people who like to collect numbers. I see full-page ads listing figures for positive stability that I know cannot be correct. Even if we give the calculations the benefit of the doubt, these numbers exist only on paper in the warmth of the designer's office. I hate to see such a dynamic situation reduced to such simplistic, two-dimensional elements. "Relax, dear, we are only heeled at 122 degrees and Bob assured me we were good to 125 degrees!" Still, the onus is on the designer to use the best tools available to try and get some kind of accurate, calculated handle on his boat's stability characteristics.

I called Bill Cook and asked him to address this area of concern. His response was as follows: "Bob is right in questioning the ultimate stability of the light, water-ballasted boats of the Open Classes; there were several capsizes in the last BOC race, and I support rule modifications currently under consideration that would improve the boats' chances of self-righting. I do think that stability calculations are extremely valuable, however. Even though they do not account for dynamics, a boat with a higher angle of positive stability (if calculated correctly) will have better capsize resistance (and capsize recovery) than a similar-size boat with a smaller angle."

"Having said that, my ability to calculate this value for Chris's boat is limited somewhat by having only estimates of the weight and center of gravity for the hull and deck. Based on these estimates, along with the known weights, my calculations indicate that, if he were sailing in 30 knots of wind (with sails shortened so that the boat is sailing at its optimum angle of about 20 degrees), a 50-knot gust would abruptly heel the boat quite hard. If this, in turn, caused an inadvertent tack, so that the full tanks were now to leeward, the boat would heel to close to 90 degrees on the other side. With all the deck openings on centerline, however (except for the escape hatch aft, which is always kept shut), there would be no flooding at this angle (the main companionway does not begin to flood unless the heel angle reaches 130 degrees)."

The SA/D of 44.33 is certainly impressive. I suppose that some day soon we will see an SA/D that is a bigger number than the D/L. We are very close in this case. Remember the old adage: "You can only handle a sail of less than 500 square feet if you are alone." The mainsail of this design, including roach, has about 1,180 square feet of sail area. You had better learn the easiest way to tuck in a reef if you are going anywhere in this boat by yourself. I suppose if the race event is designed to attract sponsors and a viewing market, the boats had better be borderline scary. Note the lack of standing backstays and the amount of roach on the mainsail. I can only imagine the loads on this rig when you do an accidental jibe. I have to assume that the designers are thinking it will never happen.

The layout of this boat shows just how much attention is paid to the creature comforts of the crew. You are out there alone, so I don't suppose there is any point in enclosing the head. Obviously the lion's share of the interior design effort has gone into the nav station. "I'm hungry and tired but I know where I am." On the other hand, I might be happier if I were well-rested, well-fed and lost.

The galley "features" a one-burner, um, burner and a sink. I wonder if you can boil a leg of lamb in a pot. Cooking is such an important part of my life that I can't imagine going so long without the luxury of creating a wonderful meal, even if I were the only person to eat it. I might even be capable of sailing faster if I could indulge myself from time to time in that diversion. "Now, where did I put the truffle oil?" But sailing hard can play tricks with your tastes. Once, on a race, I ate an egg salad sandwich and thought it tasted good. Meals in this case will be packaged, predigested foods that can be sucked out of a bag.

I'm truly envious. I'd love to be in the physical shape to do the Around Alone and I'd love to have the confidence in my own seamanship to allow me to leave my family and friends for the nine months of adventure. I can only fantasize what it must be like to look over your shoulder at a setting sun kissing the whitecaps as you leave a flattened, frothy wake at 20 knots and turn to yourself and say, "Wow!" Maybe staying here is really harder.