Mast design in uncharted waters

By Suzanne McFadden

What, rather than who, will win the America's Cup in 2000?

In 1983, it was Australia's winged keel. In 1992, the silver Cuban fibre sail and a slender boat powered America3 to victory. Last time, Team New Zealand tweaked everything and got it right.

So what revolutionary design will this America's Cup bring?

Bruno Trouble, a former French cup skipper, believes masts will make the difference in 2000. And it could well be the French who make the big move.

In last month's Admiral's Cup, French boat Crazy Coyote attempted to sail with a radical new rig.

The mast with no shrouds was designed by 25-year-old Juan Koyoumedjan, a designer with the Le Defi France America's Cup challenge.

The boat attracted a huge amount of attention, but it withdrew from the Admiral's Cup after the regatta organisers changed its rating to cut down its advantage.

Trouble, who represents challenger series sponsor Louis Vuitton, says the French syndicate are trying to raise more money to build a second new cup boat with the revolutionary mast.

"A boat must be built for it. You can't put the strange mast on an existing cup yacht - you have to have a very high deck to hold it in," he said.

"This time the America's Cup will be about masts. It's the one area that needs improvement."

The mast on the Admiral's Cup boat had a very strong carbon fibre t-frame wrapped in a clear Kevlar skin, which twisted at the top.

There has already been speculation and drama around rigs in this cup.

Team New Zealand have been seen trying out new mast configurations on the old black boats. The Spanish lost their new mast on the day their new boat, Bravo Espana, was launched.

Of the new-generation cup boats which have hit the water so far, most of the hulls are narrower, longer and as heavy as they are allowed to be.

They are clearly following the trend of the `95 Black Magics.

Team New Zealand's design head, Tom Schnackenberg, says narrower generally equals faster.

"Narrowness decreases the boat's stability - they're tippier and they aren't as powerful. But there is less drag so they may be faster," he said.

"The French boat last time was very wide, so in theory it was more powerful, but it was slower upwind in the breeze."

There is nothing in the International America's Cup Class rule to control how narrow the boats can be - only a maximum beam, which everyone nowadays shies away from.

Similarly with the length; most yachts are stretching out. But there is a trade-off in the rule - the longer your boat, the less sail area you can have.

"That's okay in the breeze and upwind, but you need more sail area downwind," Schnackenberg said.

"I think all the boats in the fleet will probably be within a foot of each other."

The weight of the boats is almost cancelled out of the equation. The maximum weight is 25 tonnes, and most are now built that heavy.

Schnackenberg believes that the dimensions of the new cup boats will all be much the same.

"The formulas will all be pretty similar. But that's where different shapes come into it. You can get quite clever about that."