His patience would be well rewarded. He now had one of the most efficient sailing rigs in the world. "I like to do innovative things," he said. "This will make an airfoil of the mast, and eliminate the turbulence you get with a round mast," he explained.
In addition to the rotating wingmasts, the rig's designer, Eric Sponberg, had designed a wishbone boom vang that may be unique. "This rig design represents my next-generation thinking," said Sponberg, a Newport, RI-based naval architect. He believes that only the rig on the mega-catamaran Team Philips comes close to his design in terms of innovation.
The rig should deliver 25 percent more power, according to Sponberg. Because there are no stays or shrouds, the sails have a full roach, and the boom can swing forward of the beam. Sponberg claims that drag is reduced significantly because the leading edge of the masts always face into the wind, and the elliptical shape of the sails is more efficient than a triangular shape. These changes mean Wobegon Daze will "get pure lift, many times more powerful than drag," said Sponberg, and "can sail fast dead downwind" with little chance of broaching.
Project Amazon is a 60-foot aluminum cat-ketch with rotating carbon-fiber wingmasts. The boat' s name reflects its owner's source of wealth: gold, extracted with ecologically friendly technology from ancient riverbeds on the slopes of the Andes. Project Amazon's owner Sebastian Reidl, had to abandon the race when the keel, where the fuel was stored, developed a leak. Repairs couldn't be made in time to continue because the owner's fortunes had plummeted with the gold market that year. A new owner hopes to enter the boat in the upcoming Around Alone in 2002.
Sponberg has worked with carbon-fiber masts and cat-ketches throughout his career. Carbon-fiber is twice as strong and 40 percent lighter than aluminum, he noted, and a carbon fiber, unstayed mast has far fewer parts than a conventional, stayed aluminum mast. In the case of Project Amazon, for example, only two partslarge bearingswere used to support the mast, compared to upwards of 500 parts needed for a conventional stayed rig. But because an unstayed mast needs to be larger than a stayed mast, the weight and cost of an unstayed carbon-fiber mast and of a conventional stayed mast are about the same.
The main drawback with carbon fiber masts, according to Sponberg, is that few manufacturers have the equipment to make them, and few have been designed. The custom design and manufacturing adds to the costs.
Rotating masts may also require some changes to other equipment. The radar, for example, may need to be mounted on a pole at the stern instead of on the mast, because the rotation of the mast will create some disorientation while using the radar. Similarly, any wind indicator mounted on top of the mast will need a centerline indicator. Orientation will also be a problem with any tricolor light atop the mast except when sails are down and the masts are lashed to the centerline; separate tricolor lights can be mounted on the pulpits to resolve this issue.
The mast fairings for Wobegon Daze (the outside shell of the mast) are hand-laid fiberglass using female molds from Project Amazon; the carbon-fiber tube inside the mast was made by a braiding machine over an aluminum tube that was removed after curing in an autoclavea pressurized oven. The masts were manufactured by Composite Engineering of Concord, MA.
Intrigued by Project Amazon, Dr. Cady began investigating how a similar rig might work for his own boat. He soon found a cat-ketch with rotating wingmasts made of wood-epoxy. The boat was up on Lake Ontario, and Dr. Cady was invited up for a sail. Convinced that the rig was more efficient than what he currently had, he commissioned Sponberg to work up a design for Wobegon Daze.
The two had worked together before on another modification of Wobegon Daze. The original Freedom design was a sloop, and when the manufacturer changed the rig to a cat-ketch, the main mast was above the bow overhang, causing it to nose-dive under sail. A new plumb bow designed by Sponberg solved that problem, and also increased the boat's speed by lengthening the waterline more than 12 percent.
Now they were working side by side on a bitterly cold day to assemble the pieces of the new rig.
The wishbones and booms were toted from nearby sheds to the snow-covered dock, hoisted aboard, and fastened to the masts. About mid-morning, the sailmaker delivered the new sails. The owner of Concordia Yachts, Brodie MacGregor, arrived to help, along with one of his yardworkers. By mid-afternoon, one of the workers from the company that had fabricated the masts showed up with two friends and helped shift the boat around the finger pier so the bow was facing into the wind. The sail cars were then slipped onto their tracks, the headboards, tacks and clews were shackled, single-line reefing and lazy jack lines were fixed, and all lines were led back to the cockpit.
"The beauty of the cat-ketch rig," Dr. Cady noted in a rare idle moment, "is you don't have to mess with spinnakers and jibs." A cruiser at heart, although he's participated in two Marblehead-to-Halifax Races and one race to Bermuda, Dr. Cady said the only foresail he plans to use is a small mizzen staysail. The boat, however, is no slowpoke. It's hit 12 knots while surfing, and can regularly clock speeds of nine and 10 knots.
As the work progressed, faults were foundthings that were not done, things that jammed, things that didn't look quite right. Numbed with cold, one of Dr. Cady's fingers slipped as he was fastening some bolts. The pristine white masts were baptized with drops of blood.
After tinkering with adjustments in the fading light, the crew mounted the snow-slippery ramp to shore and gathered to look at what they had done. It was a beautiful sight.
A week later, Dr. Cady was back. After working out a problem with the main vang, he cast off, and went sailing. The sail lasted two hours, covering the five miles to Wobegon Daze's winter berth at Fairhaven Shipyard, across from New Bedford.
"It was good," Dr. Cady said. "Everything worked well, and it moved well. I was pleased."
It was the last possible moment he could have sailed. The next day, a storm system would move in with gusts of more than 50 miles per hour, and the day after that, the insurance coverage would end.
Now, waiting for spring like other northern sailors, he has memories of that very last sail, with the wingmasts turning to cut through the air and the sails snapping into perfect shape, to carry him through the winter.
Suggested Reading List
Finding Beauty in a Junk by Michelle Potter
Optimizing Downwind Sailing by John Kretschmer
Quick Rig and Deck Check by Tom Wood
SailNet's Buying Guide - Boom Vangs
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