AMERICAS CUP 36: A Bold Leap Into the Unknown Aboard the New AC75 Foiling Monohull

7 Jan

Ready to lay eggs

You have to hand it to the Kiwis and Italians who now control the fate of the Auld Mug: they are not lacking in imagination. Nor are they unwilling to take risks. Their concept for the new AC75 monohull in which the next America’s Cup cycle will be sailed, with a pair of canting T-foils sprouting out its sides like insect legs, is both highly creative and unprecedented. My favorite editorial remark so far, from the Daily Sail’s James Boyd in a Facebook thread, is that the new AC boat looks like it wants to crawl up on a beach and lay eggs.

The easiest way to grasp how radical the AC75 is and how it will work (hopefully) is to watch the fabulous promotional video released by the Royal New Zealand Yacht Squadron:

Personally, I’m amazed–and enthusiastic–but also a bit disappointed. When I heard the next generation of AC boats would likely be foiling monohulls, I was hoping the new class rule would allow the different team designers to explore a variety of ideas of how best to exploit foils in a one-hull format. As I learned when I researched my feature story, The New Frontier, which appeared in the April 2017 issue of SAIL, there’s lots of cutting-edge work going on in foiling monohull design right now, but no clear way forward yet.

The full details of the new AC class rule won’t be released until the end of March, but it seems clear everyone participating will be forced to buy into these canting T-foils. They sure look hot in the viddy, but that’s just an animation. More importantly, it’s an animation illustrating a radical idea no one has ever tried before.

What happens if in real life the concept is a dog? The upside, I guess, is that then everyone will be racing dogs against each other. Meanwhile, the downside to a more open rule is that some teams may have dogs and others won’t, making the racing more lopsided. But still it would be fun, I think, and also instructive, to see a range of ideas being tested against each other.

Not that the new AC75 will be a cookie-cutter one-design boat. As you may have noticed in the video, it seems teams will be allowed to fool with the main hull configuration.

Open hull design

But rumor has it all the hardware associated with controlling the foils–hydraulic rams, battery packs, and what not–will be one-design kit to reduce costs, with software left open for teams to play with. Which raises the notion that the key figures in boat development might just be geeks writing code. Certainly they seemed important last time, as one big advantage the Kiwis had racing their AC50 cat in Bermuda was a superior foil-control interface. Another big question is to what extent teams will be allowed to fiddle with foil shapes. We do know that fully automatic foil-trimming systems will likely be banned, and at least some adjustments will have to be made manually, but not much beyond that.

It is also unclear what the new rigs will be like and whether teams will have much room to develop them. The Kiwis in their initial press release have stated they want to avoid the need to step and unstep masts every time a boat is sailed, as was necessary with the hard-wingsail catamarans in the last series. The working assumption is the new mainsails will be soft or semi-soft wings, with conventional soft jibs and Code Zero sails flying forward.

Meanwhile, it seems the hopes of those who want to see spinnakers again in America’s Cup competition will be dashed. The expectation is the new boats will sail faster than the old foiling cats, with speeds up to 50 knots, so the apparent wind, once again, will always be forward. Although, of course, it remains to be seen whether this will be the case in reality. Judging from the promo viddy the goal is to produce a large ballasted monohull that is airborne all or most of the time. This is well beyond the abilities of any existing design, so I’m not sure success is guaranteed.

Hull flying

One big hull flying all the time (?)

Righting moment

Lots of righting moment!

Close quarters

And maybe lots of potential for catching foils in rigs during close-quarters sailing

A number of hopeful teams have already announced they intend to play this game. We have, of course, the defenders, Team New Zealand, and the Italian Prada team, who are the challengers of record and have helped the Kiwis concoct both the competition protocol and the new boat. The New York Yacht Club has announced it will work with Bella Menta Quantum Racing to field an American challenge, and Ben Ainslie has made it clear he will return to the fight with his British Land Rover BAR team. There also is a rumor there will be another Italian team, Adelesia di Torres, from Sardinia.

Beyond that I am curious to see how many others will be willing to buy into this. It seems nothing less than a very expensive leap into the unknown. There’s really no way to train up for sailing these boats in advance, because no one has ever sailed boats anything like these before. As was the case in San Francisco during the AC34 cycle, which produced the most stunning upset in sports history, the learning curve will be very steep, and it will be fascinating, I am sure, watching everyone try to climb it.

This article was syndicated from Wavetrain


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