When the yachts of New Zealand and Britain begin the America’s Cup finals on Sunday (NZ time), Geoff Willis will be one of scores of designers and numbercrunchers back on shore, hunkered over computers and pointing at screens, sweating out each manoeuvre on the waves.

“Nerve-wracking” is how Willis describes the experience of watching Britannia from his desk in Barcelona’s old port, and that from a man who has been tried and tested by three decades of Formula One racing.

Willis leads the design partnership between INEOS Britannia and the Mercedes F1 team that started in 2019 and fully merged for this cup campaign. Backed by billionaire Jim Ratcliffe, the sailing syndicate hope their combined engineering expertise and resources will lead them to Britain’s first-ever victory in the regatta’s 173 years.

“Given the historical record and that we haven’t been, as a country, particularly shiny in the cups to date, it would be very, very special” to lift the ‘Auld Mug’, Willis told Associated Press.

So far, the union is paying off.

Britannia bested five other rivals with their consistent high speed in high and low winds, which have fluctuated wildly on the Barcelona seafront, going from under 6 knots one day to 23 knots the next. Their foiling monohull set an America’s Cup record of 55.6 knots (102 kph) last week, en route to reaching their first America’s Cup final in six decades.

It now gets a shot at toppling two-time defending champions Emirates Team New Zealand in a first-to-seven-wins match.

Car racing and yachting have converged, because this generation of America’s Cup foiling boats spend as much time flying over the water than cutting through it. That has put an emphasis on aerodynamics, a specialty of F1.

“The great thing about the Cup and Formula 1 is the amount of overlap in this sort of technology space,” said Willis. “So, yes, you’ve got a hull in water and you got foils in water, and you’ve got sails on one side, and you’ve got an engine and tires on the other.

“That’s sort of 10% of difference. There’s this 80-plus% overlap and that means that an F1 team can be involved in an awful large part of the whole programme.”

After each race, Willis and his team — which are split between Barcelona and the team base shared with Mercedes back in Brackley, England — start pouring over the data that streams in from thousands of sensors on the boat. They then try to come up with a few points that they can share with skipper Ben Ainslie and his crew.

For Willis, it is all about honing the “choreography” of steering the boat, whether upwind or down, in gusts or barely a breeze.

There are significant differences with F1 — communication with the boat is prohibited from three minutes before race start. The data analysis side has to convince, not just one driver, but eight crew members that the geeks may just know what they are talking about.

Of course, nothing compares to the uncertainty of the open sea.

“The Cup is very different,” said Willis. “The technical jeopardy is much, much higher than in F1 — is it going to touch a wave in the wrong time? — so it’s definitely more nervewracking than watching F1.”

Kiwis stick by homegrown model

By contrast, New Zealand have kept designing inhouse and that is just fine for technical director Dan Bernasconi.

Bernasconi’s team of some 40 engineers and designers has been behind some of the most daring developments in sailing. They are the masterminds of the AC75 monohull, a boat that revolutionised the America’s Cup at the 2021 edition in Auckland and has been slimmed down for Barcelona.

“I am a strong believer in our model,” Bernasconi told The AP. “We’ve been a really stable team for 12 years.

“We all know what our roles are and we work super well together, and to me, that’s more valuable than the sort of very specific goals that an F1 team might bring, but I guess we’ll find out in a few days.”

What’s better? More racing or more info?

One of the quirks of the America’s Cup is that New Zealand, as defenders, had a guaranteed spot in the finals.

They did participate in the initial round robin, but their races didn’t count. After that, they have spent the last month practicing — sometimes racing their own chase boat — and watching, as the other boats duked it out.

Bernasconi’s team has access to a lot more real and more recent racing data from Britannia’s challenger series. That intel edge can be key to not only making last-minute engineering and software tweaks, it can influence race tactics by the coaches and skippers.

“If we decided that we were 10% slower all the way around the course, then you’ve just got to make it high stakes on the start,” he said. “If you don’t start ahead of them, you’ve got no chance.

“Whereas, if you know it’s the other way round, you might say, ‘Well, let’s just stay away from them at the start, and try and keep out of trouble’.”