Team New Zealand appear to be taking the next step and foiling their massive America's Cup catamaran upwind.
Images and video have emerged from Team New Zealand's training run in San Francisco yesterday, showing what appears to be the Kiwis breaking new ground.
It could be a significant step as the research and development race intensifies for the business-end of the regatta.
Dean Barker's crew have led the way in foiling the AC72s and shown their outright speed and slick team work in downwind foiling during racing and testing.
Sail-World's resident photo and videographer John Navas captured images and footage of the Kiwis sailing a close reach with one hull right out of the water and the other slightly up on the foil.
Navas estimated the Team New Zealand boat was travelling around 30-35 knots - significantly more than the 20-23 knots they have been producing upwind in their Louis Vuitton Cup outings.
Team New Zealand are making good progress with their solo testing while Oracle benefit from having a two boat programme. Both of the cup holders' AC72s were out on the Bay yesterday.
Team New Zealand were due to go around the course solo this morning in the continued absence of Swedish challenger Artemis.
They have a race against Italy's Luna Rossa on Monday. If they win that, New Zealand will go straight through to the Louis Vuitton Cup final, leaving Luna Rossa and, hopefully, Artemis in their new boat to contest the semi-final.
Meanwhile, regatta director Iain Murray said proposals to have Artemis granted dispensation to use the now banned larger rudders on their second cat were "in the trash can". Such a move required consent from all teams but fellow challengers Luna Rossa are digging their heels in, wary of giving the Swedes any advantage.
The larger rudders were part of Murray's safety recommendations shunted through to gain a coast guard event permit for the regatta. But they were thrown out after the Kiwis and Italians successfully protested.
Now, to appease the safety issue, Murray said the four teams need to give him a detailed report on how they plan to race safely.
Those reports need to place emphasis on dealing with the danger areas on the course - the markers ending the first, third and fifth legs, when the difficult bear-away manoeuvres are required - switching from into the wind to with the wind, which proved the downfall of Artemis in it's fatal May capsize.
"Rather than any one piece of equipment being a lifeboat of safety, we're now saying a lot has changed since May 9. All the teams have learned a lot. They've raced. There's a lot more hours on the board in San Francisco. Combining all these factors has increased the safety of the teams."
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