Sailors seek high-tech help to win America's Cup

DESIGN teams from around the world are finding out right now if millions of dollars and years of high-tech research have paid off. For the teams competing in the America's Cup yachting trials off Perth, Australia, the margin of victory is often measured in seconds, a margin that each team has sought to gain using technological breakthroughs.

A week from Saturday, the second round of trials between yachts from Canada, Europe, New Zealand, and the United States begins. The boats are competing for the right to challenge an Australian boat in a best-of-seven final beginning Jan. 31. The 13 challenge boats (including five from the United States) and six Australian defenders (who began competition this week) are racing a 24-mile course.

For 132 years (the longest winning streak in the history of sport), the America's Cup rested on a trophy table at the New York Yacht Club. But in 1983 Australia II, with its innovative winglet keel design, sailed away from the US entry, Liberty, and took the cup to Australia.

After that loss, six US design teams rushed to push the limits of 12-meter-yacht design using supercomputers and other new technology. (Courageous IV, a two-time cup winner for the US, dropped out Tuesday.)

Gary Mull, architect of one of this year's challengers, watched his ship come in 23 years ago when the US yacht Constellation outsailed Britain's Sovereign for the cup. Mr. Mull was one of the naval architects who helped design the Constellation.

For the 1987 cup, Mull has designed a radically different 12-meter yacht using rudders fore and aft that he hopes will sail another US crew to victory.

As with the other boats in the cup trials, the design of Mull's boat, the USA, remains a secret. The USA left San Francisco Bay for Perth earlier this year aboard a Norwegian freighter, its computer-designed keel hidden by a wooden crate.

``None of the other naval architects really knows what another designer is doing,'' said Mull from his bungalow in the hills overlooking Oakland, Calif. ``But because a yacht designed for the Cup must follow the 12-meter rule, competing designers have their suspicions.''

Heiner Meldner, chief scientist for the USA design team, examined the winglet keel for the Enterprise two years before it competed in the 1977 Cup defense. ``Our interpretation of the rule in 1975,'' Mr. Meldner says, ``led us to believe that winglet keels violated international rules.'' The Australia II, with help from Dutch designers, proved Meldner wrong.

Meldner, a research scientist at the nearby Lawrence Livermore National Laboratories, led a development team of more than a dozen scientists and engineers who calculated the lift and drag of a number of keel and rudder designs which were considered by Mull for the USA.

Meldner used a Cray-XMP/48 supercomputer to simulate the performance of the USA's designs in a large test tank. Cray Research donated over $1 million worth of computer time. The SailAmerica yacht, based in San Diego, also used a Cray-XMP/48 supercomputer.

``Our designs are conceptually different from all others,'' says Meldner. ``Among naval architects, a breakthrough design increases the speed of a boat by 1 percent.'' All other things equal, a boat with a breakthrough design should finish ahead of its competitor by a quarter of a mile in a 24-mile race.

``The Intrepid, with its fin keel design, made all other 12-meter designs obsolete in 1974,'' Meldner says. ``The Australia II, with its winglet keel design, made fin keel boats obsolete in 1983.'' If Meldner's prediction holds true, the keel and rudder design of the USA will surpass the winglet keel used by its competitors for the 1987 America's Cup.

``We used hundreds of hours of computer time on the Cray-XMP/48 for modifying the keel and rudder design to fit the USA's hull,'' Mull says. ``We also used a personal computer, the Tandy 3000, to assist in hull and structural design.''

The crew will use computers on board the USA to determine the performance they are getting out of the boat. ``If the skipper finds himself sailing upwind in 18 knots of breeze, he'll know that he can have a certain angle to the wind and get so much speed out of the boat,'' Mull says.

``But computers can't sail boats. A skipper can look ahead on the water and see a puff of wind. A computer can't do that. A skipper can see how the other boat is sailing. A computer can't do that.''

Mull says the designers of the cup boats have taken into account the course in the Indian Ocean off Perth. Mull himself studied five years of data from a weather buoy off Perth to determine local wind speed and direction. ``We have a good idea of the weather we can expect in Australia during the series,'' he says.

Australia II, a short boat with a large sail area, won the America's Cup in 1983 with a design suited to the light early summer winds off Newport, R.I. The winglet keel saved the Australia II in the harsh winds of the 1983 final. Longer boats with less sail area should fare better in the heavier winds and choppier seas off Western Australia.

``There is still a fair amount of art to racing and designing 12-meter boats,'' Mull says. But he is trying to change that, ``because we would rather calculate differences than hope for them.''

All of the design work untaken by Mull and his competitors must meet rigid specifications for 12-meter yachts spelled out by the International Yacht Racing Union. The term ``12 meter'' does not refer to the length of the boat, as commonly thought. The 12-meter rule is determined by a formula that takes into account both the length of the boat and the area of the sail. The yachts must also meet provisions governing shape, minimum weight, and displacement.