Big questions for Team New Zealand after Aotearoa capsizes in America's Cup semi-final racing in Bermuda: Sailing expert

It was a disastrous day of sailing for Team New Zealand today. Photo / AP

Team New Zealand should make sure their catamaran is fixed before heading back on the water tomorrow after this morning's dramatic capsize, says an expert.

Aotearoa capsized on the start line this morning, tipping over in the semi-final America's Cup battle against Britain's BAR. It was nine minutes before the vessel on which New Zealand has fixed its Cup dreams was righted.

All the sailors are safe, but footage from Great Sound in Bermuda showed the catamaran had been damaged.

Just how significantly is not yet clear, professor of Sport and Recreation Mark Orams told Tony Veitch this morning.

Orams, who is also a competitive sailor and coach, said only Team New Zealand will know if the damage can be repaired before racing resumes tomorrow.

"You put it in that hard and that fast, the damage is not insignificant. Is the damage superficial or is it structural?"

The team had already switched their damaged wing for a spare immediately before the capsize, and now the spare wing was also damaged.

The first wing would need to be repaired overnight, Orams said.

The effect on the electronic and hydraulic systems would also need to be assessed, as they were underwater for a long time, he said.

"There's a lot of question marks that need to be answered before we know whether she can sail again."

Team NZ were leading the best-of-nine semi-final qualifying series 3-1 before the disaster, and now had big decisions to make, as winds are expected to be significant again tomorrow.

If Aotearoa was not ready to return to the water tomorrow, the team could find themselves in a bigger hole: more damage to their boat coupled with losses.

"My call would be, if the boat's not ready, don't sail it."