Sinking feeling for £5m America's Cup boat

Team Dennis Conner's latest America's Cup boat, launched in May, sank in 55 feet of water at the southern entrance to Long Beach Harbor, California, on Tuesday. A loud crack had been heard from the area of the rudder, which reportedly detached from the hull. All the crew were rescued and there were no injuries.

The boat was recovered in the early evening and an investigation began in earnest yesterday morning.

Stars & Stripes, USA 77, was trialling against its stablemate namesake, launched late last year, when the damage occurred. It is understood that the crew could not keep pace with the flow of water into the hull despite using airbags and on-board auxiliary pumps.

Conner was not aboard but was on the scene in minutes. "We feel extremely fortunate that no one was hurt," he said. "The hull appears to be in good shape and the mast is fully tensioned and does not appear to be damaged."

He said he was confident the £5m boat could be repaired in time for the Louis Vuitton Cup, the challengers' trials for the America's Cup which begin in Auckland on October 1. "Our training programme will proceed as scheduled," he said, "with the last sailing day on Thursday and both boats being shipped to New Zealand separately during the first two weeks of August."

Though there is no official word on the cause or indeed the area of the failure, it has given rise to much speculation.

Conner is thought to have been testing a new concept - a keel turning on a near-vertical pivot, allowing the angle of attack relative to the hull's centre-line to be altered slightly on each tack to increase keel lift and reduce hull drag. Or it may be that the American veteran is trying a twin-rudder configuration, with a second one mounted forward of the keel.