United States challenger American Magic capsized and was at risk of sinking after attempting a high-risk maneuver in a squall on Sunday on the third day of racing in the America's Cup challenger series.
A race involving firemen, coastguard and American Magic's rivals immediately began to save the yacht, named Patriot, and to keep the U.S. team in the regatta.
Defender Team New Zealand and challengers Luna Rossa and Team UK hurried to aid the American team, saving sails and equipment and assisting desperate attempts to keep Patriot afloat.
As night drew in, the American yacht had begun to settle in the water, even as mobile pumps worked furiously to empty the hull, suggesting it might have been holed when it crashed onto its side while leading a race against Luna Rossa.
Patriot was surrounded by chase boats and tenders from American Magic and rival teams as efforts were made to stabilize the yacht and eventually to attempt the 10-mile tow from the racecourse back to its base in downtown Auckland, New Zealand.
American Magic was chasing its first win in the Prada Cup after three straight losses and rounded the last mark ahead of Luna Rossa when disaster struck. A savage gust of wind in a rain squall ahead of impending thunderstorms struck the American yacht, which soared into the air, then crashed heavily onto its side, likely driving the port foil into the hull.
None of the crew was injured and all were recovered safely.
The New York Yacht Club-backed team tweeted, "Awful end to what was looking like a great race for Patriot. We have confirmed that all crew are safe."
Inflatable bags or buoys were attached to keep the yacht on the surface, and it was eventually lifted upright, off its side, to allow sails to be lowered and removed. At first, the wind dropped and the sea state improved to aid salvage efforts.
The sails later were raised again as Patriot seemed to settle, its decks awash.
If the yacht can be saved, American Magic has four days to repair Patriot before the next round of racing begins Friday or could choose to race its first-generation race boat, an extremely risky step that would likely place it at a disadvantage against its rivals.
Sunday's incident was not the first time an American team has suffered a dramatic setback during America's Cup racing off Auckland. During the 1999-2000 the New York Yacht Club-backed yacht Young America cracked open while leading a race in rough weather. Skipper Ed Baird ordered the crew to abandon ship, and all were plucked to safety. The boat also was saved.
In 1995, the Australian yacht OneAustralia broke its back and sank rapidly in racing off San Diego. The semifinal race had just started when OneAustralia suffered a massive structural failure.
Strong but shifting winds on Sunday produced the most dramatic racing of the series but nothing more dramatic than Patriot's capsize, which forced American Magic to retire from the second race of the day. Earlier, Britain's INEOS Team UK came from behind to beat Luna Rossa by 18 seconds for its fourth win in as many races.
Team UK leads the three-team series with four wins from four races. Luna Rossa and American Magic have yet to post a win.
American Magic seemed to be heading for its first win on Sunday when disaster struck. After losing the start, it showed good boat speed in winds that initially fluctuated between 12 and 18 knots to lead by six seconds at the first mark.
Both boats headed to the left-hand side of the course as the wind swiveled from north to west, and Patriot extended its lead over Team UK's Britannia to 15 seconds at the second gate and to 27 seconds at the third.
The wind continued to shift left throughout the race, and American Magic, as the leading boat, was well-positioned to capitalize. At the fourth gate, its lead was 42 seconds, and it seemed favored to win the race as the axis of the course was skewed by the shifting wind.
Round the final mark, American Magic was in a strong puff of wind, and as it attempted a tricky maneuver at speed, it was struck by the gust, which hurled it up, then on its side. The yachts attained speeds of around 34 knots upwind and 45 knots downwind in winds that fluctuated Sunday between 8 and 26 knots.
That meant the 75-foot yachts, racing on foils like low-flying aircraft, were often operating near the limits of their known performance. American Magic's attempt to jibe in those conditions, a move it might not have been able to practice or perfect, was precarious and the results were calamitous.
The unpredictable nature of Sunday's conditions was shown earlier in the day when the first attempt to sail the race between Luna Rossa and Team UK had to be abandoned when the wind shifted more than 90 degrees after four of six legs.
Team UK had trailed the Italian yacht early but made a smart decision to separate after the second upwind leg and sailed into a big shift, which carried it into the lead. Britannia was ahead as it approached the fourth gate, but the wind suddenly switched 90 degrees, from north to west, and dropped, forcing the decision to abandon the race.
The re-sailed race took place in winds of between 13 and 16 knots, tending northwest. Luna Rossa again won the start and led at gate one. But the British boat seemed consistently to point higher and produced better VMG (velocity made good) or speed in a direct course to the next mark.
The boats were side by side after the third leg, but Team UK made the decision to pursue a shift on the right-hand side of the course and was lifted as the wind tracked in that direction. It took the lead and, reaching 43 knots on the last leg, was 18 seconds ahead at the finish.