British Olympic gold medalist Andrew "Bart" Simpson died tragically on Thursday when his yacht capsized in the waters on San Francisco Bay during training for the upcoming America's Cup.

Andrew "Bart" Simpson was part of an 11-man crew aboard Artemis Racing's 72-foot-long AC72 vessel when the boat flipped northwest of Treasure Island about 1 p.m., officials said. Simpson, 36, served as the Swedish team's strategist.

An America's Cup chase boat pulled the sailors from the water, but Simpson was trapped under the 72-foot catamaran for up to 15 minutes before he was reached, San Francisco Fire Department spokeswoman Mindy Talmadge said. Simpson and the others were rushed to shore, but despite CPR efforts, Simpson was pronounced dead at the nearby St. Francis Yacht Club.

At least one other sailor suffered cuts, but declined to be taken to a hospital.

A statement from Swedish team Artemis Racing, which owns the yacht Simpson used Thursday, on the team website said: "Despite attempts to revive him, by doctors afloat and subsequently ashore, his life was lost."

Simpson won the gold medal in sailing at the 2008 Beijing Olympics and took the silver in London in 2012. He also was the gold medalist at the 2010 World Championships in Brazil.

Simpson joined Artemis in February. It is one of three teams of top sailors competing for the chance to challenge Oracle Team USA in the 34th America's Cup, set for this summer in San Francisco.

The America's Cup is the elite competition in yachting that is funded by billionaires and traditionally dominated by the U.S. since it started in 1851.

Teams from only four nations have won it: the United States, Australia, New Zealand and Switzerland. The New York Yacht Club held the cup for well over a century.

Coast guard officials were not sure what caused the yacht to capsize.