Sport: Knock on Wood

Wood was out and aluminum was in. That was the new gospel circulating in the rarefied world of 12-meter yachting after the last America's Cup races in 1970. No matter that aluminum-hull boats had never competed in yachting's most prestigious international competition. Designers were convinced that the lightweight metal vessels would be speedier and cheaper to build. Olin Stephens, the world's foremost yacht designer, who conceived three of the last five Cup winners, created Courageous.

Maverick Designer Britton Chance also worked with aluminum in producing Mariner, a vessel with radical new lines.

In Australia, Millionaire Land Developer Alan Bond, pledging to win the Cup that American boats had owned for 123 years, ordered up a $2 million metal boat he named Southern Cross.

Major Surgery. By last week the aluminum revolution was looking a good deal less robust. With the second round| of trial races under way in the waters off Newport, R.I.—the Cup had been postponed a year to give designers time to work with their new technology —wood looked as good as ever.

Intrepid, the wooden-hulled winner of the last two Cups, had been quietly cast off by her East Coast backers after the victory in 1970. She was bought by a Seattle group and placed under the direction of San Diego Yacht Builder Gerry Driscoll, who is competing in his first Cup race. With the low-key Driscoll at the helm, Intrepid and her 13-man crew have beaten the new boats six times while losing only three races.

The losses were against Courageous. Intrepid's ebullient supporters have responded by plastering their cars and yachts with KNOCK ON WOOD bumper stickers. There are even some Frenchmen who may be smiling too. Only one foreign boat can become the official challenger, and to earn that designation the favored Southern Cross will have to beat France, a wooden vessel owned by French Bic Pen Tycoon Baron Marcel Bich.

The New York Yacht Club, holder of the Cup, is not scheduled to pick an American defender until final trials next month; it is still too soon for the aluminum backers to abandon ship. Optimism, though, is difficult to find in the Mariner camp. Brit Chance's boat was in drydock last week undergoing major surgery. The reason: her radical design —a hull that had a blunt, "fastback" stern instead of the traditional tapered underbody—simply had not worked.

Many yachtsmen have been skeptical about the boat ever since her unusual design became known. "I hope she does not work," said one rival designer, "or I will have to forget everything I ever learned." Even Mariner's supporters had fears. Skipper Ted Turner thought the boat "did not look right" when he first saw her. M.I.T. Hydro-dynamicist Jerome Milgram, who did preliminary consulting for Chance, had warned in a 1972 article that promising test-tank readings might not be reliable.

Hard Lessons. Chance nonetheless pushed ahead. Tank tests were indeed glowing, and he was convinced that Mariner's sawed-off stern would produce less water resistance along the boat's hull and increase her speed. The results, of course, could not have been worse. Mariner lost her first two meetings with Courageous by four and eight minutes at a regatta on Long Island Sound in June.