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The America’s Cup is more high-tech than ever

Sailing at the limit

The America’s Cup is one of the oldest contests in sport. But, as Matthew Symonds reports, the competing boats use technology at the cutting edge

The America’s Cup is one of the oldest contests in sport. But, as Matthew Symonds reports, the competing boats use technology at the cutting edge

Matthew Symonds | June/July 2017

It is more like flying than sailing. The boats that will compete for the 35th America’s Cup in Bermuda from May 26th can skim across the water at nearly three times the speed of the wind that is propelling them. With the wind behind them, they will hit 55mph. Even more remarkably, when tacking against the wind, the 50ft carbon-fibre catamarans are still capable of flying on their foils a metre above the waves at speeds of up to 30mph.

Since 2010, when Oracle Team USA (owned by Larry Ellison, the multi-billionaire founder of the Oracle business-software firm, and led by Sir Russell Coutts, a New Zealander and serial America’s Cup winner), ripped the “auld mug” from the tenacious grasp of the Swiss team, Alinghi, America’s Cup racing has undergone a revolution. The boat that won the 33rd America’s Cup was a 90ft trimaran with a sail bigger than the wing of a Boeing 747.

It was a far cry from the previous AC class, the elegant 12-metre monohull sloops that rarely exceeded 15mph. But Ellison and Coutts had a vision: to make one of the world’s oldest sporting contests (first raced in 1851) a compelling spectator event in which the best sailors would sail the fastest boats. As holders of the cup, they had the privilege of setting the rules. And in the past seven years, they have gradually turned it into something much more like Formula One on water.

At the 34th America’s Cup held four years ago in San Francisco, they realised part of their ambition. The match racing between 72ft catamarans tearing up the bay on their foils between Alcatraz Island and the Golden Gate Bridge was visually spectacular. It was also the stage for one of the greatest comebacks in sporting history. The holders, Oracle, were down 8-1 to Emirates Team New Zealand in the best-of-17-race series, but came roaring back to win 9-8, leading the previously dominant Kiwis to the line in the final race by 44 seconds. America’s Cup racing was no longer just for sailing nerds.

In the two years running up to this year’s cup, six teams have competed at venues all over the world, such as the Solent, Fukuoka, the Gulf of Oman and New York, in so-called “one-design” – that is, identical – AC45s, which look like scaled-down versions of the AC72. This series of fleet races, in which all six boats sail against each other at the same time, has attracted vast crowds on shore and a growing television audience, thanks to cameras that take the viewer on board and computer graphics that explain exactly what is going on.

At this stage, nobody knows which of the five teams competing in Bermuda for the right to challenge Oracle for the cup in June will have the winning combination of superior boat speed and slickest sailing team.

The boats that will be racing are an entirely new America’s Cup Class (ACC). With a length of 50ft, they are much cheaper to build and operate than the AC72s, but they are nonetheless faster, while being technically much more sophisticated than the AC45s. Their reduced size means that their shore “footprint” is smaller, so more teams can fit their bases along a given waterfront, and they can be packed into a standard container for shipping and reassembling anywhere in the world. Another cost-saving measure is the requirement for all teams to use the same hulls, central “pod” structure and cross beams. Costs have roughly halved, and revenues should increase. Coutts hopes that should encourage as many as 12 challengers for the next America’s Cup in 2019.

Standardisation brings with it another advantage. The teams are not tempted to experiment with structures that may exchange weight for fragility. While practising before the racing began in 2013, both Oracle and Artemis, the Swedish team, had catastrophic accidents when their boats broke up after capsizing, the latter resulting in the death of the British Olympian, Andrew “Bart” Simpson. The distinctive 25-metre high wings, which take the place of sails, will also be a single size and shape, although teams are allowed some refinements of their own.

This wing, shaped like an aircraft’s with a wide, rigid leading edge made of carbon fibre and a slim, soft trailing edge, will give each boat its vast power. Instead of using differential pressure on either side of a piece of sailcloth, like conventional sails, the two-part wing is shaped to produce lift, as well as forward momentum. The crews control the amount of forward thrust by adjusting the angle of the two elements from which the wing is constructed, rather in the way that pilots use the flaps on their wings. Sensors embedded in the wing provide information to the sailors electronically, which allows them to keep the wing in the most efficient shape.

Give us a wave!

Oracle’s “grinders” hard at work

The power of the wings, combined with the rudders tipped with T-shaped elevators and the hydraulically operated dagger boards with L-shaped carbon-fibre horizontal foils, is what makes it possible for these big boats to pop out of the water and glide above it. By rising above the water, the boats lose a large amount of drag and reduce the effects of wave action. The teams are allowed complete freedom in the design of everything that functions below the surface of the water.

All the computer systems and sensors on board, including the wing controls, are also custom and there are no limits to the onshore computing power the teams can field. By analysing the constant flow of data that is sent from the boats while they are sailing, shore-based engineers can make tiny adjustments to the wings and foils to maximise both hydro- and aerodynamic efficiency in different wind and sea conditions – a crucial source of competitive edge.

The design of the dagger boards has advanced steadily over the past four years, while the control systems that operate them and the wings have made, according to Coutts, “a quantum leap” thanks to the hundreds of fibre-optic sensors embedded throughout the boat that feed back information. He believes that under most wind conditions the new boats will be able to stay up on their foils around the entire race circuit.

That means that the crews will be tacking and gybing without ever coming off their foils, an astonishing feat of technology and sailing skill. To ensure that the boats can foil in the widest range of wind conditions, each team is allowed two sets of dagger boards, one that has a foil with a bigger surface area for light airs and one that is smaller and optimised for stronger breezes. Getting the best mix of sizes means accurately forecasting months ahead the likely weather conditions the teams will race under.

Being able to switch dagger boards means that even if there is not much wind, spectators will still see the boats flying. In less than 16 knots of wind, the boats are still expected to achieve their maximum speed of about 55mph (which is ultimately limited by cavitation, the point at which water starts to boil around the edge of the foils). The range of wind conditions under which racing can take place will also be much wider than before – between six and 25 knots.

Coutts says that widening the weather envelope is vital because it reduces the chance of races being delayed or called off – a nightmare for television schedulers and teams alike, as sponsors are only prepared to pay top dollar to get their names on the boats if TV exposure is guaranteed. The America’s Cup now has all the visual excitement needed to become a major television sport, but people tuning in to give it a try will not come back if there’s no racing to see.

Yet for all the exotic technology, television audiences also want to believe that the individual brilliance of the athletes – and on these boats, all six crew have to be extremely fit – can affect the outcome. British sailing fans were convinced that a major reason for the turn in Oracle’s fortunes in 2013 was the late arrival on the boat of Sir Ben Ainslie as tactician. (It certainly helped, but so too did some critical tweaks to the wing and foils.) Ainslie now has his own team, Land Rover BAR Racing, which is one of the favourites to challenge Oracle. Coutts would be the last person to belittle the importance of the human factor. “Sailing techniques will be critical,” he says. “A great deal comes down to intuition.”

Ian “Fresh” Burns, Oracle’s performance director, says that the technology places new demands on the crew. “Everything happens so much faster. Milliseconds are vital. The boat is now fundamentally unstable. If the skipper lets go for an instant, it will crash.” Jimmy Spithill, Oracle’s pugnacious driver, sometimes presses the control buttons working the dagger boards 100 times a minute. If a boat comes off its foils at the wrong time it can “pitchpole”, burying its bows in the water and turning over.

These boats are safer than the terrifying AC72s, but there is still a long way to fall if they capsize. Teams fear, above all, losing a man overboard close to the scything foils, as happened to Oracle’s Graeme Spence in February when he plunged between the hulls (he emerged unscathed). America’s Cup racing may have gone high-tech, but it is more than ever an extreme sport with crews stretching their boats to the limit and beyond.

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