Highlights

America's Cup reveal design secrets for winning sport's trophy

(AP)
Updated: 2007-04-02 09:13

Defending champion Alinghi and its 11 challengers revealed their design secrets Sunday for the America's Cup.

Team members joined the public in touring bases to snap photos of rival yachts ahead of Monday's deadline of declaring race boats for the Louis Vuitton Act 13, from April 3-6.

BMW Oracle design team member Juan Peinado compared technical demands on the boats to challenges faced in Formula One.

"It's like an F1 car having a different chassis for the race in Nuremberg and Monte Carlo," Peinado said about BMW Oracle's two boats, USA 87 and USA 98. "We have parts that work better for one and one for the other. The boats are completely modified to do two different jobs."

Looking at the yachts Sunday, team designers said the overall design this time was more evolutionary than revolutionary.

Still, as the bottom of the hull and the keel bulb were revealed for the first time, the surprise came in the different designs between each team.

"I was surprised that we have seen so many variations," Alinghi architect Rolf Vrolijk said.

The shape of the 20-ton (18.14-metric ton) keel bulb is elemental to the boat, as it alleviates some of the up to 50 tons (45.36 metric tons) of pressure that the main mast brings down on the 2-ton (1.81-metric ton) hull. The keel bulb's size could also decide how the boat will react to Valencia's relatively unstable winds.

"Making an accurate judgment of the wind is the key to staying in this competition," Emirates Team New Zealand designer Andy Naughton said. But "it will come down to the sailors."

Keel bulbs on display varied from four to eight meters (4.4 yards to 8.75 yards) in length with winglets sometimes positioned at the back, or completely flat, and some longer than others.

It's just one of the many configurations that designers have been grappling with for more than three years.

"The trade-off between stability and resistance of the hull is what designers have to wrestle with, on top of trying to judge downwind performances," Luna Rossi designer Claudio Maletto said. "The U-shape section of our boat is gone and is now square because we're focusing on upwind racing."

Wind range has made the design increasingly complicated. Teams with the funds to field two boats are able to test and research around this. Others must hope they have come up with the best overall package.

"The biggest difference this time is that the sails and the shape of the main sail is very different than it was before and it's a radical challenge to the sail designers to come up with the right sail," United Internet Team Germany designer Axel Mohnhaupt said.

Teams can make changes to their boat between regattas, up to 24 hours before the start of racing. After that a small and a large change are allowed, though within a set of limits.

It means designers can still fiddle with their boats right up to the America's Cup race.

"What you see out here is not necessarily what you will see on the race day. It can take only a day to change the boat if it needs to be," BMW Oracle grinder Scott Crawford said from beneath the hull of USA 98.

The Louis Vuitton Act 13 is the final stage of a three-year regatta to decide seedings ahead of the Louis Vuitton Cup, of which the winner will race Alinghi for the America's Cup from June 23-July 4.

Emirates Team New Zealand currently leads the rankings with 125 points, followed by BMW Oracle Racing with 123 and Luna Rossa Challenge with 118.