How a technological revolution that took shape in Valencia changed sailing and eventually found its way back

In engineering, revolutions rarely begin with a single invention.

They emerge through a sequence of decisions (and mistakes!). Someone questions an established rule. Someone else takes an idea further than originally intended. A technology developed for one purpose reveals another possibility. What initially appears extreme eventually becomes familiar, and the next generation starts from a point that the previous one considered almost impossible.

Modern high-performance sailing is a remarkable example of this process.

Today we watch F50 catamarans flying above the water at extraordinary speeds. Foiling has become part of the vocabulary not only of the America’s Cup and SailGP, but of an entire generation of sailing disciplines. Wing foiling, kite foiling and many other applications have made the image of a vessel rising above the surface increasingly familiar.

But the path that brought competitive sailing here was neither obvious nor linear.

And an important part of that story leads back to Valencia.

Valencia, 2007

When Alinghi defended the America’s Cup in Valencia in 2007, the boats themselves still belonged to a relatively conventional world.

The 32nd America’s Cup was raced in International America’s Cup Class monohulls (IACC). These were sophisticated racing machines, the product of enormous engineering effort, but their fundamental architecture would still have been recognizable to generations of sailors before them.

What happened afterwards would be very different.

Following Alinghi’s victory, disagreements over the terms of the next challenge eventually developed into a legal dispute. After two years of litigation, the 33rd America’s Cup became a Deed of Gift match between Alinghi and BMW Oracle Racing. The usual class framework effectively disappeared and the two competitors arrived in Valencia in 2010 with extraordinary 90-foot multihulls: Alinghi 5, a catamaran, and BMW Oracle Racing’s trimaran USA 17, popularly known as “DoGzilla.”

The contrast with 2007 was enormous.

These boats demonstrated another scale of sailing performance. USA 17 combined its gigantic multihull platform with a rigid wing sail, and BMW Oracle Racing won the match 2–0. The America’s Cup left Valencia for San Francisco.

Something else left Valencia with it: a different idea of what an America’s Cup boat could be.

When speed became part of the spectacle

The lesson of 2010 was difficult to ignore. Multihulls could produce levels of performance that dramatically changed the visual experience of sailing.

Under Larry Ellison and Russell Coutts, the next America’s Cup would push that idea much further.

There was a broader ambition behind the change. Sailing had always been technically sophisticated, but its complexity could also make it difficult for a non-specialist audience to understand. A boat travelling at ten knots may be fascinating to an experienced sailor who understands everything happening on board, but speed communicates differently. It is immediate. Visible. Instinctive.

The ambition was increasingly to create something closer to a Formula 1 experience on water: shorter racing, closer to spectators, with boats whose acceleration and speed could communicate performance without requiring decades of sailing knowledge.

The multihull provided the platform. The wing sail provided another leap in performance. And then something happened that would change the trajectory again.

The boats began to fly

For the 34th America’s Cup in San Francisco, the AC72 was created: a 72-foot catamaran powered by an enormous rigid wing.

Foiling was not initially the defining concept of the class. But Emirates Team New Zealand found a way to make its AC72 rise onto its foils. What had begun as a new generation of extremely fast multihulls suddenly became something else entirely. Soon, the other teams were flying too.

By 2013, AC72s were sailing at more than 40 knots. Oracle Team USA eventually defeated Emirates Team New Zealand 9–8 in one of the most extraordinary comebacks in the history of the competition.

But the significance of San Francisco went beyond the result.

Once a racing yacht had demonstrated that sustained foiling could transform the performance of a large sailing multihull, it became very difficult to imagine going backwards.

The question had changed. It was no longer simply how fast can we make a sailing boat? It was becoming how much of the boat still needs to be in the water?

The people behind the wave

Technological revolutions are often described afterwards as though they were inevitable. They never are.

Behind every change are people willing to challenge assumptions that others consider fixed. The transformation of high-performance sailing involved hundreds of designers, engineers, sailors, builders and researchers, and it would be misleading to reduce such a collective achievement to a handful of names. But some individuals were positioned unusually close to the sequence of changes.

Coutts’s vision was backed by Ellison, and among the designers who, in Valencia, began working out how to put this new push toward speed into practice were, among others, Mike Drummond (who would later play an important role in SailGP), Scott Ferguson, Murray Jones, Manolo Ruiz de Elvira, Joseph Ozanne, Mario Caponnetto, and many more.

Their roles were different, and they were far from alone. But this intersection between sporting vision, naval architecture, hydrodynamics, simulation and the willingness to experiment is fundamental to understanding what happened next.

In Valencia the debate was whether the more spectacular boat was a monohull—something like a Classe Libera from Lake Garda—or a catamaran like the Extreme 40, which was ultimately used for racing trials and which helped inspire, with a rigid wing, the one-design AC45 class. A kind of think tank that can be seen as the embryo of everything that came afterward.

Because the revolution was not simply about adding hydrofoils to a boat. It was about changing the way racing yachts were conceived.

From the AC72 to the F50

The line connecting San Francisco with what we see today is remarkably clear, although it passes through another generation of America’s Cup boats.

After the AC72 came the smaller AC50, used for the 35th America’s Cup in Bermuda in 2017. Foiling was no longer an unexpected interpretation of the rules. It had become fundamental to the architecture of the boat. America’s Cup itself describes the period from 2010 to 2017 as the moment when the Cup went “extreme, and airborne.”

And when SailGP was launched in 2018 by Larry Ellison and Russell Coutts, the technological inheritance was unmistakable.

The F50 was developed from the AC50 platform used in Bermuda, but extensively redesigned. SailGP describes it as the culmination of a decade of development in high-performance foiling multihull racing. The original America’s Cup platforms were stripped back and transformed with new foils, systems, hydraulics and other technologies to create a one-design fleet capable today of exceeding 100 km/h.

This distinction matters.

The F50 is not literally a scaled-down AC72. But conceptually, there is a clear technological lineage: the extreme multihulls of Valencia made speed central; the AC72 demonstrated the potential of large foiling catamarans; the AC50 refined the concept; and the F50 transformed that accumulated knowledge into a global racing platform.

The continuity is perhaps more interesting than any individual boat.

A revolution beyond one competition

Something else happened along the way. Foiling escaped from the America’s Cup.

Today hydrofoils appear across an extraordinary range of sailing applications and disciplines. The underlying technologies, scales and histories are not identical, and it would be simplistic to claim that they all originated in the America’s Cup. But elite competition has an unusual capacity to accelerate technological development.

It concentrates talent, investment and engineering effort around problems whose solutions may initially appear unnecessary. Reducing drag by another percentage point. Controlling ride height more precisely. Understanding ventilation. Designing structures capable of surviving extreme dynamic loads. Coupling aerodynamic and hydrodynamic performance. Eventually, ideas migrate. What begins at the edge of competition becomes accessible elsewhere.

And yesterday’s radical experiment becomes tomorrow’s normality.

Progress and conservatism

Every technological transition creates resistance.

There are good reasons for this. Engineering conservatism is not inherently negative. Boats operate in an unforgiving environment, and reliability, safety and accumulated experience matter enormously. Innovation without judgement can be merely novelty.

But absolute conservatism creates another risk. If every new idea must first prove itself using the standards of the technology it is intended to replace, meaningful change becomes almost impossible.

The history of high-performance sailing over the last two decades demonstrates something fundamental about engineering progress: the final destination does not need to be visible for the first step to be worthwhile.

Nobody standing in Valencia in 2007 needed to know exactly what an F50 would look like in 2026.

And yet the clue was already there: around 2010, you could see C-Class catamarans flying on foils under a rigid wing, the very formula that defines top-level sailing today. Even with the answer in plain sight, the imagination struggled to believe the America’s Cup could be reshaped so completely, which is exactly what makes the progressives who pushed for it deserve credit.

The wave returns

Almost twenty years after the 32nd America’s Cup brought the centre of the sailing world to Valencia, another fleet of extraordinary racing machines is arriving in the same waters.

This September, SailGP has come to Valencia.

The F50s that raced here belong to a completely different technological generation from the monohulls that competed for the America’s Cup in 2007. Yet there is a historical thread connecting them. Valencia witnessed the end of one era of America’s Cup sailing and, particularly through the extraordinary 2010 Deed of Gift match, helped create the conditions for another. The pursuit of speed led to multihulls. Multihulls opened new possibilities. Foiling transformed those possibilities. The lessons moved from one generation of boats to another, and eventually beyond the America’s Cup itself.

Now the wave comes back.

Perhaps that is the most interesting thing about technological revolutions. We recognize them clearly only in retrospect. While they are happening, they look like individual decisions, experiments, disagreements and sometimes even mistakes.

We cannot know what sailing boats will look like one hundred years from now. But we can know one thing. If nobody changes the boats we have today, the boats of tomorrow will never arrive.

How a rule we wrote badly made us win and changed sailing

When we at Oracle, as defender, drafted the AC72 class rule for the America’s Cup, we wanted to keep the boats in the water. We already investigated foiling—and full-scale tested a skimming one—on the trimaran of the 33rd America’s Cup, the giant BOR90 «Dogzilla» that beat Alinghi in 2010. We had seen multihulls fly, and we judged full foiling too dangerous for a 72-foot catamaran with eleven crew. So we wrote that the daggerboard was «primarily used to affect leeway.»

It wasn’t enough. A definition describes what a thing is—it doesn’t prohibit what it can also do. Team New Zealand read the gap correctly and made the boat fly.

Here’s the paradox. Because we had ruled foiling out of our own thinking, we spent our effort somewhere else: the aerodynamics of the platform. The Kiwis bet everything on flight and neglected the air.

Then flight became everyone’s. And once you’re foiling at 40+ knots, the hulls leave the water, hydrodynamic drag collapses, and it’s aerodynamic drag that sets the limit. The boat we had shaped for a world without foils was the cleaner one in the air. Same foils, higher speed and our aerodynamics made the difference, especially upwind.

And yet that same gap we failed to close turned out to be a gift. Opening the door to foils unleashed a movement far bigger than one Cup: it reshaped sailing, gave rise to circuits like SailGP where whole fleets now fly, spread to powerboats, and opened up entirely new ways of moving on water, all the way to the wing foil. Sometimes the rule you didn’t write well is the one that lets the future in.

So here’s the question I still ask myself: what would the world of sailing look like today if we had chosen one word more carefully in the definition of a daggerboard? A butterfly effect—one clause in a rulebook, and perhaps an entire era of flight might never have taken off.