Compare the foil shapes! America's Cup 2017 - Photo: Ingrid Abery
New Zealand's foil design was right at the limit of speed, stability and structural integrity. The long spans and short chords of their light air boards provided speed over a wide wind range, but at the risk of breaking. In fact they did damage those boards right after launching in Auckland. During the challenger racing they were caught out one day with the light air boards in the boat on a high wind day. The young sailing team showed great discipline in sailing conservatively to minimize risk. Even so, hairline cracks developed and the boards were inspected with ultrasound every day.
Long span and short chord of New Zealand's America's Cup winning foils - Photo: Steve Tsuchiya
The Kiwi victory provided a master class in running an America’s Cup campaign. Their role as the lone wolf among the challengers made their achievement all the more impressive. The combination of sailing skills, innovative design and disciplined management came together in the performance we saw in on the Great Sound. Through most of the campaign, the team prioritized designing for speed and manoeuvrability rather than on sailing technique. They were confident they could polish their boat handling once they arrived in Bermuda. They also knew that they would continue receiving hardware upgrades all the way through the challenger selection series. In fact the first time they had the boat in its final configuration was 27 hours before the first race of the match.
Intelligent risk taking in the design program paid off handsomely. The pedal driven grinding stations provided more power, which could be used for a fully hydraulic wing trim system. Pedaling also left the hands free so that Blair Tuke could control the foils, leaving Peter Burling to focus on speed and tactics.
Wing trimmer Glenn Ashby used twist control more than traveler adjustment. Keeping the angle of incidence of the wing more constant made it easier for foil trimmer Blair Tuke to manage the ride height and stability. All of this was enabled by having more power from the cycle grinders.
The combination of cycle power, separating foil trim from helming and fully hydraulic wing trim allowed manoeuvres that the other teams did not have. When they were able to foil tack the boat on their fourth day of sailing in Auckland, they developed the confidence to stay focused on design and speed rather than sailing technique, counting on their sailing ability to learn to use the speed once they started racing.
The tradeoffs that were made months earlier came together perfectly to deliver a dominating win for Team New Zealand.