The New York Yacht Club's America's Cup entry Young America cracked in the middle in strong winds in the Hauraki Gulf off Auckland, New Zealand, today and most of the 16 crewmen leaped off as it appeared to be sinking.

For the second straight time in an America's Cup regatta, sailors jumped into the sea to escape going down with their $5 million racing yacht. But although it wound up low in the water, Young America somehow avoided sinking, unlike OneAustralia, the Aussie challenger that broke in half at the deck and shot to the bottom off San Diego in 1995 to take dubious honors as the first boat ever to sink in a Cup race.

"The boat cracked in two," said Bruno Trouble, a former Cup skipper and now press officer for the Louis Vuitton Cup, the four-month series of preliminary races underway to pick a challenger for the 30th Cup match against Team New Zealand. "The crew jumped" and was quickly picked up by support craft with no injuries. "After a while they realized it was still taking water but not sinking," Trouble said.

A few crewmen who stayed aboard the charcoal-colored 75-footer set to work salvaging sails and gear. The boat, said Trouble, who watched the drama on closed circuit TV as it was beamed live back to the mainland, "looked like a banana" with bow and stern ends sticking up out of the water and the middle nearly submerged.

Crewmen cleared as much gear as they could off the boat, then brought high-powered bilge pumps and inflation bags aboard to keep it afloat. As of 9:30 p.m. EST yesterday, the ruined yacht was being slowly towed toward Auckland Harbor eight miles away.

"They want to get it back into port to find out what happened, and also to save the mast, which is very valuable," Trouble said. "But they must tow it very slowly because the boat is very bad. The bow and the transom are sticking high out of the water."

Photographer Bob Greiser, who was near when the accident occurred, said Young America was making one last tack to approach the final turning mark of the 18-mile race. "As they came through the tack a huge roller lifted the bow and slammed it down, then another came in and did the same. That's when the boat buckled," he said.

The crackup occurred 15 miles into the race in winds of 18 to 20 knots and seas of about four feet. Young America, which stood second in the challengers standings with a 10-2 record, was 26 seconds ahead of its competition for the day, the Japanese boat Nippon.

Breakdowns have plagued many of the 11 Cup challengers since racing started in October. The ultralight Cup boats generate extreme loads on both hull and masts with their towering, 110-foot high sails balanced against 35-ton ballast bulbs at the bottom of the keels.

The hulls are made of carbon fiber, an extremely strong, light material. Veteran sailors including Nippon's skipper, Peter Gilmour, and Bruce Nelson, designer of the San Francisco entry AmericaOne, have fretted publicly about the tremendous forces at work on the boats as they bash through Auckland's fresh breezes and choppy seas.

Last month, just a few weeks into the 4 1/4-month-long regatta, the Swiss entry FAST 2000 had to pull out of the first round of racing when the deck shattered near a crucial fitting while racing in strong winds. Sailors on all the boats speak of worrisome creaks, cracks and groans they hear while racing when the breeze is up and several boats have dropped out of races with mast and rigging problems. But nothing like Young America's catastrophic breakdown had occurred since racing began.

The accident deals a sharp blow to the highly touted New York Yacht Club entry, which was designed by Annapolis resident Bruce Farr and was at the top of the fleet, trailing only undefeated Italian entry Prada in the standings.

But Young America is a two-boat program with another new Cup boat back at the dock, so the syndicate may be able to scramble and prepare its second yacht for competition without losing too many points.

The mishap called attention once again to controversial challengers regatta rules, which call for no racing if winds of 18 knots or higher are sustained for five minutes before a start, or winds of 23 knots or higher are sustained for five minutes during a race.

Those limits have been criticized by many sailors as too restrictive, since wind conditions in the Hauraki Gulf are commonly at those levels. Team New Zealand has made it clear no such limits will be in effect for February's Cup match, a best-of-nine final series between the top challenger and the New Zealand defender.