America's Cup bosses have promised a full investigation into the accident in which British Olympic gold medal winner Andrew Simpson died.

The 36-year-old was a star of the British Olympic sailing team, winning Star gold alongside Iain Percy at Beijing 2008 before taking silver on the home waters of Weymouth and Portland last year. Simpson had made no secret of his desire to also achieve success in the America's Cup and became strategist at Swedish challenger Artemis Racing, whose sailing team director and tactician is close friend Percy.

However, Simpson, affectionately known as Bart, died when he was caught underneath the team's AC72 catamaran which capsized during training on San Francisco Bay.

Stephen Barclay, the chief executive officer of the America's Cup Event Authority, told BBC Radio 5 Live: "The Artemis Racing team were out training on the boat and the boat capsized. "Andrew was caught underneath and was under there for a few minutes.

"By the time he was brought to the surface and CPR was administered, sadly he passed away. It's a very tragic day for everybody."

The question now is why the accident occurred - something Barclay has promised to find out.

"One of the things about accidents such as these is that there is lots of speculation about various aspects of what happened," Barclay said.

"What we do know is that he was trapped underneath and it was for a few minutes, we're not sure if it was one, two, three or 10. "I imagine that'll be in the evidence when we review what actually happened.

"These boats are very fast and if these sorts of things happen then there are procedures and those sorts of things that we follow.

"We have boats follow these vessels, there's divers and doctors in case such things like this happen and those procedures were followed."

It is not the first time one of the speedy America's Cup catamarans has capsized, with Team Oracle's AC72 last year also going over.

"Oracle Team USA have a similar boat in terms of length and that also capsized in San Francisco Bay," Barclay said.

"Thankfully no one was injured in that instance. "As with high-performance sports, where athletes are pushing themselves in their craft to their limits, sometimes things go wrong, that's the nature of what they do."

When then asked if any changes would be made to the specifications of the America's Cup in light of Simpson's death, Barclay was keen to avoid making any rash remarks.

"Right now, we, the America's Cup, are trying to establish what happened," he added.

"Artemis Racing, Andrew and his team were out there practising.

"They weren't in event mode or anything like that so what we'll be doing is reviewing the circumstances and try to understand exactly what happened and remove all the speculation to find out the facts.

"Then we'll review what we've found and if there is a need to make changes, we'll make them. "But we won't make a judgement now about what might happen in the future." Artemis chief executive officer Paul Cayard said: "We obviously had a tragic day today on the bay and our thoughts and prayers are with Bart Simpson's - Andrew Simpson's - family, his wife and kids, and also with the rest of the team-mates.

"It is a shocking experience to go through and we have a lot to deal with in the next few days in terms of assuring everybody's well-being.

"The boat itself is under control, but it is certainly not the first of our concerns. We are focused on the people. "That is what we are working with and on and we will give you more information when we are able to."

The Royal Yachting Association released a statement early this morning after receiving the tragic news.

"We're devastated by the news from San Francisco today," RYA performance director John Derbyshire said.

"Andrew is someone I've worked closely with since the age of 16 - he was a great talent, and a key figure in our World class programme over many years culminating in his well-deserved Olympic success.

"He was a huge inspiration to others, both within the British sailing team and across the nation and our deepest sympathies go out to his family at this terrible time."

The British Olympic Association said in a statement: "We are devastated to hear about the tragic training accident in San Francisco which led to the loss of Olympian Andrew Simpson's life.

"Andrew was a treasured and accomplished member of Team GB, both at the home Olympics in London 2012, where he won silver with Southampton sailor and childhood friend Iain Percy in the Star class, and at the Beijing 2008 Olympic Games, where he won the gold medal also sailing alongside Iain.

Andrew's talent and humour was an inspiration to others and he will be sorely missed by the Olympic Family. "Our heartfelt condolences are with Andrew's family, friends and fellow athletes during this very difficult time."