The hydrofoil sailing revolution started by the America’s Cup

The ultra-fast hydrofoil techology seen on the boats now contesting the America’s Cup has revolutionised the face of sailing, from the very top to the grass roots. Matthew Sheahan reports

SoftBank Team Japan, one of the Challengers in the 35th America’s Cup, in practice off Bermuda
SoftBank Team Japan, one of the Challengers in the 35th America’s Cup, in practice off Bermuda | Image: ACEA 2017/Photo Ricardo Pinto

When the Challenger and Defender head out into Bermuda’s Great Sound tomorrow, their arrival will mark the start of the 35th iteration of the ultimate duel in sailing, the America’s Cup Match. Yet despite its prestige and history, this 166-year-old event will, this time, be nothing like anything that has gone before it.

At just 15m long, the boats are the smallest the Cup has ever seen, but they are also the fastest sail-powered, waterborne racing yachts ever built. The races in which they will compete for the most prestigious prize in sailing, and the oldest trophy in international sport, are also the shortest of any America’s Cup to date. Little surprise, perhaps, that the traditionalists are up in arms.

The Formula White-produced F101 foiling boat, £17,500, has been designed for amateur sailors
The Formula White-produced F101 foiling boat, £17,500, has been designed for amateur sailors

The America’s Cup has come a long way in the past six years. Aside from a radical change in the style of boats that now zip around the course on hydrofoils, the build-up to the event has changed significantly too.

Since Oracle Team USA successfully defended the America’s Cup back in 2013 in San Francisco, six teams have toured the world with identically matched 14m catamarans during the past two years, competing in the America’s Cup World Series – a mid-cycle preamble, if you will. Among the stops on the tour were Portsmouth, Chicago, Muscat and Fukuoka. Each event delivered points counting towards a ranking and bonus system that the top teams carried into this year’s America’s Cup showdown. Having risen to the top after a series of round robins and knockout stages over the past four weeks, the successful Challenger, Emirates Team New Zealand, now squares up to the current Defender, Oracle Team USA, in the simplest of contests – head-to-head match races in a first-to-seven win series.


In less than a decade, the boats they will race have changed radically, thanks to big steps forward taken by Cup technology. Top speeds now exceed 50mph as crews provide Herculean levels of muscle power to fuel complex, manually driven hydraulic systems that both lift the 15m carbon fibre catamarans clean out of the water and control their solid wing sails.

Impressive though they are, the current breed of Cup machines bear little resemblance to the average racing boat, big or small, and are as far removed from the grass roots of sailing as it is possible to get. The crews also bear little similarity to the everyday racer. Dressed in helmets and body armour, and equipped with sophisticated, built-in personal communication systems, they wear oxygen bottles and carry large knives. They have undergone rigorous and nerve-wracking sea survival training to cope with the worst, should it happen.

The 10m GC32 inshore catamaran, €406,800, is used in the Extreme Sailing Series
The 10m GC32 inshore catamaran, €406,800, is used in the Extreme Sailing Series | Image: Jesus Renedo/GC32 Racing Tour

And, in their quest to get match-fit, they have worked as long and as hard as any elite athlete (many are themselves Olympic medallists), resulting in substantial changes to their physiques over the past two years. The race format has changed dramatically too. The one-to two-hour courses set well out to sea a decade ago have been replaced by 20-minute, adrenaline-fuelled, high-speed sprints around a course laid close to the shore, in full view of the spectator grandstands.

No matter from which angle you look at the modern America’s Cup, there is little chance of finding any similarity between this competition and the sport enjoyed by most of the rest of the sailing world. And yet the current America’s Cup cycle has triggered one of the biggest and most far-reaching revolutions in sailing ever. And at the heart of this revolution are hydrofoils.

The Formula White-produced Whisper foiling catamaran dinghy, £22,500, capable of over 25 knots
The Formula White-produced Whisper foiling catamaran dinghy, £22,500, capable of over 25 knots | Image: Dave White Photography

The ability to raise a boat out of the water in order to reduce the drag of the hull(s) is nothing new. The time, effort and money that now go into making foiling systems work, however, is. From offshore monohulls and multihulls to the current Olympic-class catamarans, from kiteboards to junior classes as small as the Optimist dinghy, foiling has become the talk of the dockside wherever you are in the world. “Before the recent Cup boats it was really only the International Moth class that was foiling in any numbers,” says boat builder and former Olympic sailor Rob White. “The Cup has pushed huge sums of money into foiling development, way more than any other area of the sport, and this has had a big knock-on effect and accelerated development.”

White builds boats at both ends of the performance scale, starting with one of the world’s most popular single-handed dinghies, the Topper (£2,795), more than 49,000 of which have been produced. At the high-tech end, Formula White manufactures a number of high-performance race boats including a new foiling catamaran dinghy, the Whisper (£22,500), a boat that is aimed at club sailors and enthusiastic weekend warriors rather than foiling experts. “It’s an all-carbon-fibre boat that is capable of over 25 knots, yet easily sailed,” says White. “It’s proved popular with the 50-plus market, but having said that, it’s really only the price tag that puts it in this age bracket as there are plenty of 20-year-olds who want to sail one too.”

The new 14m DNA F4 offshore racing catamaran, €1.92m, also rides on foils
The new 14m DNA F4 offshore racing catamaran, €1.92m, also rides on foils

White is about to start producing another foiling boat aimed at amateur sailors, the F101 (£17,500), once again hoping it will be a game-changer on the club sailing scene. But White’s projects aren’t unique – far from it. A steady stream of foiling boats started to appear shortly after the last Cup – boats like the Flying Phantom (Essentiel, €26,280) and the Nacra 20FCS (€40,800) became popular in the high-performance scene – and the trend is continuing. One of the latest additions to the canon being the Olympic catamaran, the Nacra 17 (€28,800), which will gain hydrofoils to replace its conventional daggerboards this summer in preparation for the 2020 Olympic Games. Bigger boats are sprouting foils, too, such as the GC32 (€406,800), a 10m inshore catamaran that is used in the Extreme Sailing Series and the DNA F4 (€1.92m), a new 14m offshore racing catamaran that also rides on foils.

It’s not just multihulls that are at the sharp end of this trend – monohulls have started to muscle in on the foiling scene too. The International Moth has long been a popular foiling boat in dinghy-racing, and initially helped to feed foiling knowledge into America’s Cup teams. The Cup has returned the favour by generating interest in the class, but it remains a notoriously tricky boat to sail. In contrast, a retrofit kit has been developed for one of the easiest dinghies to sail, the Laser (from £5,500), which converts the world’s most popular single-handed dinghy into a foiling boat.

High-performance craft such as the Flying Phantom Essentiel, €26,280 are becoming increasingly popular
High-performance craft such as the Flying Phantom Essentiel, €26,280 are becoming increasingly popular | Image: Pierrick Contin

Meanwhile, in the offshore keelboat scene, foils are also becoming popular. Earlier this year, at the Vendée Globe, the single-handed, non-stop race around the world, seven of the 29-boat fleet of 18m grand prix machines had hydrofoils designed to generate more power from the same sail plan by partially lifting the large carbon hulls out of the water. This summer, a giant 32m hydrofoiling trimaran, the Maxi Edmond de Rothschild, is due to be launched in an attempt to break the outright, fully crewed, non-stop around-the-world record: one that many believe can now only be broken by using foils. Towards the end of the year, around 90 solo skippers in the diminutive 6.5m-long Mini Classe will race over 4,000 miles across the Atlantic, many of them using boats that now feature hydrofoils.

And it’s not just the sailors that are keeping their eyes on foiling: event organisers are watching carefully too. “We’re seeing huge leaps in performance like never before,” says Volvo Ocean Race CEO Mark Turner. “There’s no doubt that foiling is spreading across the whole sport, right to grassroots level. It doesn’t mean that everyone will be going foiling, but people like to go faster. It comes with some risks, though, especially for race management. There’s going to be some damage, some human damage potentially, and we have to be conscious of that and be realistic about how the level of risk has gone up in the sport.” The use of body armour and helmets – not just in the professional ranks, but now among amateur sailors at club level too – is evidence of this shift.

High-performance craft such as the Nacra 20FCS, €40,800, are also becoming increasingly popular
High-performance craft such as the Nacra 20FCS, €40,800, are also becoming increasingly popular

But there are areas outside the sport that are also being influenced by the Cup and the machines it is creating. Martin Whitmarsh was at the helm of McLaren for 25 years. Today he is the CEO at British America’s Cup team Land Rover BAR (Ben Ainslie Racing). His appointment brought a wealth of knowledge and contacts from Formula One that were of use to the LRBAR design team. But he was also sought for his experience in finding the kind of commercial opportunities, beyond the sport itself, that helped McLaren expand from a £19m business to one with a turnover of £650m. He sees a similar concept being possible through America’s Cup campaigns. “When you consider the technology in our everyday cars – crossply tyres, electronic ignition, variable cam timing, ABS braking, traction control and stability control systems – [you see that] Formula One is a hotbed for development,” he says.

A similar example of technology transfer can be seen in the team’s partnership with Land Rover. Initially, the vehicle manufacturer provided key resources and expertise during the design and testing of the boats. But as Ian Anderton, head of thermal and aerodynamics at Jaguar Land Rover explains, the knowledge has flowed the other way too. “One of the major areas of our work with the team was in wingsail development. In order to optimise the wingsail we linked a fluid dynamics system that models the airflow over the wing with a structural mechanics system. This meant that our aero simulation could calculate the wind loads on the wing and feed the resultant data into the structural system to establish how the wingsail would bend and react. From this, the computers then remapped the airflow to the new shape before feeding it back into the structural model. This is a first in our industry and, while it was important in BAR’s design, it’s also allowed us to refine the design of body panels, which need to be increasingly light and yet stiff. We can use a similar process for glazing, sun roofs, soft tops and doors.” Such partnerships have been more common in this Cup cycle than previous editions, as similar technical requirements from different industries converge.


Yet exciting though it is, the longer-term future of the Cup has been a tougher nut to crack. A well-known saying in America’s Cup circles states, “You win the Cup, you make the rules” – a reference to the say the winner of the trophy has in shaping rules such as the size and type of boat, the venue and the race format for the next context. That the Cup holder has such influence is both the allure of the Cup and a drawback. For winners and losers, it has been difficult to look beyond one Cup cycle with any certainty. But this time around, a framework agreement has been reached before racing has started, with five of the six teams agreeing on several details going forward.

For Ben Ainslie Racing’s co-founder Sir Keith Mills, stability in the Cup is key for its future in the modern, commercialised world. “One of the big steps forward in creating this framework agreement is that it has dealt with much of the usual uncertainty about the boats and the length of the Cup cycle, and placed us in a position where we as a team can enter negotiations with our commercial partners on the basis that the America’s Cup will take place in 2019 and 2021. For instance, we would know that it will be in very similar boats to the ones that we are currently racing in, and there would be a World Series of up to eight to 12 events in major cities around the world. The blank sheet of paper that was traditionally presented to teams after each event had been won has gone away, and that’s a big step forward. It’s still got a long way to go compared to, say, tennis, football and Formula One, but it’s a good step in the right direction.”

Many would agree. Meanwhile, regardless of who wins the 35th America’s Cup, there is little doubt that this Cup cycle has been the most radical and influential period in the history of the oldest international sporting trophy: a point that will be driven home once again on the race course today.