America's Cup 2017: Will mind or machine win the day in Bermuda?

It's one of the most grueling events in world sport -- but what will it take to win the 2017 America's Cup?

The answer is somewhere between cutting-edge technology and good old-fashioned team spirit, according to the sailors, designers and engineers who are hoping to win the 165th edition of yachting's most prestigious event.

"I think the most important thing is actually going to be team culture -- the team that can hang together

America's Cup veteran Dean Barker, who is heading up the first Japanese-flagged challenge since 2000, feels ultimate success will "come down to having the best equipment."

In December, the competing nations will launch their final AC50 race boats for next year's competitions in Bermuda.

Each has worked in near-total secrecy as they develop what they hope will be the technological innovations that make the key difference out on the water.

The wingsail catamarans will be 50-foot long, weighing 2.4 tons and crewed by six sailors. Their top speeds will be in excess of 45 knots (50 mph), using foiling technology that raises the boats out of the water to reduce drag.

The approach will differ from team to team. Britain's Land Rover BAR, for example, is using -- computer wizardry performing tasks that would normally need human intelligence -- to analyze every aspect of boat performance.

Led by multiple Olympic champion Ben Ainslie, BAR following last weekend's penultimate leg in Toulon.

But will machine or mind turn out to be the factor that wins the day in June?

Technological innovation is not all there is to it, says Jimmy Spithill, skipper of defending champion Oracle Team USA, who thinks lifting the trophy "will come down to the people and, ultimately, the better team."

Spithill and his crew have been undergoing a punishing training regime which pushes them to their physical limits, helping them to make split-second decisions in exhausting race situations.

Ainslie, seeking to win the cup for Britain for the first time, says each boat's daggerboard -- a blade-like element that reduces leeway,- will prove "the biggest differentiator in the performances."