Another great article from Wired News on the building, design, and racing of the new America Cup's boats:
http://www.wired.com/magazine/2011/08/ff_americascup/all/?pid=6441&viewall=true
Winging It: America's Cup Racers Push the Sailboat to Its Limits
· By Adam Fisher
· August 18, 2011 |
One prediction is that the next America's Cup will "meet the expectations of the Facebook generation, not the Flintstone generation."
Photo: Thomas Heinser
John Kostecki has one instruction for me: "Hold on." It's a sunny day in New Zealand's Hauraki Gulf, off the coast of Auckland, and I've just boarded Kostecki's boat. Actually, calling it a boat suggests something a lot more substantial than what I'm standing on. It's the barest skeleton of a raft, a wisp of a catamaran 22 feet wide by just under 45 feet long. Called an AC45, it's a bantam version of the next-generation America's Cup yacht, and it's unlike anything else on water. Above me is not a sail but a solid wing, mounted vertically like a fin. At 70 feet tall, it is longer than the wing of a Boeing 727. Yet the craft that this massive airfoil propels is almost fully dematerialized—a CAD file in wireframe hovering over the bay. As far as I can tell, there's nothing to hold on to.
As the craft bobs idly in the water, Kostecki, the boat's tactician, motions for me to head out to the center of the netting stretched between the two knifelike hulls, a place where I'm least likely to get in the way. The skipper, Jimmy Spithill, watches silently from behind mirrored sunglasses as I crawl out and embrace the base of the mast. As soon as I'm settled, the three other sailors on board begin to stir their winches. This causes a cat's cradle of lines to spring up all around me and begin to dance. Just above my head is the wing's bottom edge, a massive horizontal pole with a half dozen separate lines running in and out of it. It's like a giant robot's arm strung with rope tendons, and as it starts to flex—positioning the towering wing to catch the breeze—the boat accelerates with a gut-twisting quickness. Within seconds we're outpacing the speedboat that dropped me off. A rooster tail of spray shoots from the bow of each hull, leaving me thoroughly soaked.
Next, accompanied by the terrible groaning howl of rope straining under maximum tension, the boat starts to tip up onto its side. One of the hulls lifts free of the water. "Hike out!" Kostecki barks, and the crew races—half running, half speed-climbing—to the high side of the boat. "Sorry, mate," says one sailor after trampling across my back and flinging himself over the breaching hull. Their weight is the only thing keeping us from flipping. To gain maximum leverage they hang off the boat upside down, facing up, with their feet tangled in the netting and everything past their knees cantilevered over the side. The goal is not to bring our wayward hull back to the water but rather to bring it as close to the surface as possible without touching down. Flying the hull eliminates its drag. Flitting across the water, literally and figuratively on edge, the black carbon-fiber boat takes on a distinctly alien, insectoid grace. The next America's Cup race takes place in 2013, but one thing is already sure: The event's pioneers wouldn't recognize their sport now.
Back in 1851, when the stately yacht America bested the greatest naval power that had ever ruled the seas to win the cup, Queen Victoria, in a bit of stiff-upper-lip hopefulness, famously asked who took second place. "Your Majesty," the queen's counselor advised, "there is no second." And that is really the key to understanding the oldest trophy in international sport. The America's Cup—the Super Bowl of sailing—is unique among major competitions in that it's essentially structured as a winner-take-all bet. The grand prize of the America's Cup race is dominion over the next America's Cup race. It's as if the Green Bay Packers were rewarded with not just the Vince Lombardi Trophy but also the NFL. Or if the San Francisco Giants were now in charge of baseball, and not just the Major Leagues but the Japanese and Cuban leagues, too. The team that takes the cup gets nearly complete control over the race, the only caveat being that an official "challenger of record" must agree to the final rules. No wonder the world's richest men have always been so keen on the contest.
The last cup, in 2010, was a highly contentious battle between Oracle Racing, bankrolled by Oracle CEO Larry Ellison, and Alinghi, the alter ego of the Italian-born Swiss billionaire Ernesto Bertarelli. It marked what may be the nadir of the sport: Alinghi, who won the previous cup, attempted to radically change the rules by using a sham challenger of record. Ellison's organization sued and won, becoming the official challenger, but as a result the match reverted to the anything-goes rules of the 19th century. Alinghi spared no expense on a specially designed high-speed catamaran. Oracle spared even less expense, devising a paradigm-breaking trimaran with a wing for a sail. Oracle won.
Wing-sail technology carried the day, but the acrimony over the rules seriously tarnished the potential value of Ellison's prize. Old-line sailors tsk-tsked about the abandonment of the traditional single-hull yacht design. Never before had there been two crass-looking multihulls competing for the America's Cup. And Ellison's wing? For traditionalists, it was downright offensive. But even worse for Ellison, the masses—especially the young—tuned out the competition entirely, turned off by the endless lawsuits and massive egos. Facing this reality, Ellison did what any successful businessperson would do after acquiring an underperforming asset: He ordered a shake-up. Instead of bringing back the design rules that had governed the sport for 15 years, Ellison decided to completely reinvent the race. The next America's Cup will, as Oracle Racing's CEO Russell Coutts puts it, "meet the expectations of the Facebook generation, not the Flintstone generation."
The new America's Cup boats are so fast and nimble that they almost want to flip. Oracle's Russell Coutts takes a header in San Francisco Bay.
Photo: Gilles Martin-Raget
America's Cup 2.0 is still two years away, but the beta is already here: the America's Cup World Series. Featuring everyone from Oracle Racing to Team Korea, the series is a preseason road show, a tour of racing events meant to build public awareness of the main America's Cup event, which will be held in San Francisco in September 2013. Ellison's new cup has two points of distinction. For starters, the rules will be fair. Teams will sail the same basic boat, which means the America's Cup events will measure the skill of the racers, not their lawyers. The second distinction is the radical new design formula: ultralight, ultraquick, wing-powered catamarans. Ellison is gambling on untested technology—one that will be world-record-setting fast, very hard to sail, and completely unforgiving of mistakes.
Oracle Racing
Larry Ellison's plan for overhauling the America's Cup—and winning it—hinges on his team of sailing superstars.
Ian Burns
The team coordinator. Helped design the AC45.
Tim Smyth
The master boatbuilder. A whiz with carbon fiber.
Russell Coutts
The veteran skipper. CEO of Oracle Racing.
Jimmy Spithill
The prodigy. Youngest skipper ever to win the cup.
Illustrations: Joel Kimmel
In their final build, these boats will be 72 feet long and carry a crew of 11. But before that can happen, racers need to learn how to sail ultralight, ultraquick, wing-powered catamarans. Right now, that's a challenge for even the world's most experienced sailors. So, for the World Series, the competition will race the scaled-down AC45—the boat I clung to for dear life in New Zealand.
The AC45s carry five sailors and are capable of reaching speeds of up to 40 mph. All are made by the same boat fabricator in New Zealand. Their mix of speed and agility, their skittishness, and a blue-sky design that no one's ever raced before mean that spectacular crashes and capsizes aren't just likely, they're inescapable.
It's a Silicon Valley cliché that every bold idea must start life hidden away in someone's garage, and the new America's Cup is no exception. In this case, yacht makers, event officials, and racers are holed up in a complex of boat sheds in Auckland's Viaduct Harbor. Upstairs in one building is a loft strewn with folding tables, chairs, and cat-5 networking cable—squint and it's a startup. It's here that officials are trying to sort out everything from how races will be run to how they might be televised. All of it is given careful thought with an eye to bringing back audiences. A memo is going around: Yachts will no longer be referred to as "yachts"; instead, they are "boats." Similarly, "protocol" is "rules," "syndicates" are "teams," and "sailors" are henceforth "athletes." Another missive lays out the alphabet soup of overlapping authorities. The America's Cup Event Authority is in charge of marketing the event, while another organization—America's Cup Race Management—runs it. Ellison established both organizations, but they are nominally independent of him and make their decisions based on what's best for the cup. In a surprisingly self-aware and forward-looking move, Ellison has created an infrastructure that he hopes will last—something that can weather the loss of any one billionaire patron.
As for the boats themselves, the brief that came down from Ellison was to "make it exciting to sail, exciting to watch," says Ian Burns, Oracle Racing's team coordinator who was one of the leaders on the AC45 design team.Ellison wanted a new class of boat, one that sacrificed everything for speed. To a mechanical engineer like Burns, speed "is a simple equation," he says. "It's the amount of horsepower you've got divided by the amount of drag you have to fight."
Burns started with horsepower: the design of the mainsail. From a physics perspective, in terms of how much lift—and thus power—a sail can create, there's no real question. Wings beat soft sails, without a doubt. "A traditional sail will always have that droopy catenary shape," Burns says, "but you can have any shape you want in a wing." It turns out the shape you want is an elongated teardrop, thick and rounded headed into the wind with a trailing edge that tapers into a thin wedge. "With a traditional sail, the maximum lift coefficient you can generate is around 1.2, but these wings," Burns says, gesturing toward an AC45 floating in the harbor, "can get coefficients up to 2 or more." With the AC72s the coefficient could go up to 4 or 5. Wing-sails are simply more powerful.
Furthermore, a wing requires much less boat. To hold a soft sail in shape, you have to pull it tight from the lower corner using a rope called a mainsheet. "And that takes an astronomically high amount of tension," Burns explains. For example, USA-17, the boat that won Ellison the last America's Cup, was fitted with both a soft mainsail and a wing-sail. The mainsheet tension needed to control the shape of the soft sail was on the order of 20 tons. "That's about the weight of 10 Chevy Suburbans hanging nose-to-tail off the back of the thing," Burns exclaims. To support this load, the boat has to be fairly burly. The rigid wing-sail, on the other hand, holds its own shape and thus exerts much less of a load on the boat itself. As a result, the craft doesn't need to be nearly as substantial.
Oracle's second major design decision, after choosing a wing over a soft sail, was to choose between a multihull (catamaran or trimaran) or traditional monohull (the kind of boat conjured up by the word yacht). But after the load calculations were done, the AC45′s catamaran configuration was cast in carbon, so to speak. Compared to monohulls, "multihulls, almost by definition, weigh less," Burns says, and therefore generate "less drag when pushed through the water." Every design cue goes back to that fundamental calculus of speed: power over drag. "Multihulls are almost always more powerful, faster, more extreme," he says.
They are not easy to control, however. Actually sailing one of the new America's Cup boats is a feat akin to having a crew of daredevil wing-walkers fly an aerobatic plane from outside the fuselage using a system of ropes that thread into the cockpit and are tied to all the essential controls: the throttle, the foot pedals, the yoke. Things go wrong all the time—lines jam, tangle, get loose—but it makes for an exciting spectacle.
1/ Inspectors examine the 70-foot wing of an AC45.
Photo: Gilles Martin-Raget
2/ A bolt of one of the several types of carbon fiber used to build the boats.
Photo: Gilles Martin-Raget
3/ The 45-foot hulls of an AC45, almost fully assembled.
Photo: Gilles Martin-Raget
4/ A computer-controlled mill turns CAD files into precision molds for carbon-fiber parts.
Photo: Gilles Martin-Raget
The trick of sailing an extreme machine like the AC45 is to keep all the powerful forces that act on it in proper balance. Take a wave the wrong way and the AC45 will respond by burying its nose in the chop. That's like slamming on the brakes—the drag on the boat skyrockets when the hulls are forced to plow deep furrows into the water. This can cause the wing to simply outrun the craft, flipping it. "When we designed the boat we had visions of capsizings where the whole wing detonates," Burns says. "We imagined nothing left except a couple of hulls and a crossbeam or two."
The AC45 has a power-to-weight ratio 3.2 times greater than the old monohull designs. Not only that, the acceleration and handling characteristics of a wing-sailed catamaran are completely different from those of a monohull with soft sails. Here, in the choppy waters off Auckland, the most skilled and experienced sailors on the planet are learning the basics of boat handling all over again, attempting to deal with a radically overpowered machine that almost wants to flip.
By the time I arrive in New Zealand in May, pretty much all the teams on the water have rolled their AC45 at least once. "It's actually been a pleasant surprise," Burns says. "To date, there's been very little damage—we haven't had a catastrophic capsize, touch wood." The AC45 is so light and has so little inertia that in a capsize it tends to lose nearly all its speed just before the wing slaps down on the surface of the water. It's a much less destructive fall than the reverse situation, an upside-down skid, where the sail stops the forward motion of the boat by digging under the waves.
"That wasn't necessarily good design," Burns adds, "so much as a lucky break."
Burns and the team designed the boats, but it's Tim Smyth's job to get them made. A tall, affable Kiwi, he and his business partner, Mark Turner, are in charge of boatbuilding for Oracle Racing. Their team built the largest wing-sail ever made—for USA-17—and is now working on the dozen or so AC45s that have been ordered by race teams from around the world. Smyth's workshop-factory is in the village of Warkworth, 45 minutes north of Auckland, in the cavernous hulk of a former printing plant. "During the last America's Cup I was trying to keep wing-making a secret because it was a big leg up," Smyth says. But now that Ellison holds the cup and everyone is using the same design, he adds, "we show all the teams how it's done." Conceptually, laying carbon fiber is no different than laying fiberglass. There's epoxy resin, a catalyst to activate it, and then the material itself—in this case, carbon fibers rather than glass fibers. Yet there is an art to it.
The process starts inside a walk-in freezer. The temperature is arctic, and the lone lightbulb is not strong enough to illuminate the far corners of the long, low-ceilinged room. Industrial racks lined up like a regiment of soldiers hold bolt after bolt of sticky black fabric. "We are vertically integrated," Smyth says. "Nothing bigger than a drum or a roll comes through the door." A couple of months later, out goes an AC45.
The rolls are sheets of carbon fiber in a nearly raw form. Unspooled, a bolt of carbon looks like something you might find on the floor of a barbershop—if every hair were combed across a paper backing and hair-sprayed into place so that they all lay in the same direction. The sticky "hair spray" is actually the slow-acting epoxy resin impregnated into the carbon. The freezer retards the catalyst. Once the rolls are pulled out of cold storage, however, they'll go stale in about four weeks.
Some of the fiber goes into making large standardized panels. The carbon-fiber sheets are unrolled and hand-laid on big cutting tables in a chilly, temperature-controlled, and positively pressurized clean room. Care is taken to arrange the layers so that fibers cross north-south, east-west, and at every compass point in between. Then a high tech honeycomb material called Nomex (a relative of Kevlar) is laid on top of the carbon fiber, and another layer of crisscrossed carbon fiber is laid on top of that. The Nomex-and-carbon-fiber sandwich is then bagged under vacuum pressure, loaded onto baking racks, and rolled into a hot oven the size of a small garage. At 185 degrees, the epoxy begins to flow, catalyze, cure, and finally set. The result looks like a cross between obsidian and cardboard, feels like a superlight plastic, and performs like steel. Smyth calls it, with a bit of wry disdain, "black aluminum." Boeing uses a lot of "black aluminum" in its new 787 Dreamliner. A Nomex-carbon panel makes a fine stand-in for plain old plate metal.
But to Smyth, this so-called black aluminum is actually a waste of carbon's potential. "To fully utilize composites you need to take a more bioengineered approach," he says. "You can contour carbon to make all the fibers follow the load paths—that's where the skill comes in." To do this, carbon fiber has to be carefully draped in layers over molds that will give it a final shape. It's the difference between turning the stuff into a stand-in for metal, which then has to be cut to shape, and turning the sheets of carbon fiber directly into the thing itself. The art is in laying the carbon fiber thick where it needs to be and thin where it doesn't. It's a very human, artisanal process at the heart of a factory filled with machine tools, water- and laser-jet cutters, milling machines, and computers. Doing it well requires an uncanny understanding of the forces that stress each part. Carbon is brittle if the fibers are not oriented in the direction of force, so the contouring process is actually more akin to weaving or felting than traditional shop work. "There is a lot of tailoring," Smyth says, observing that parts made in this manner tend to look more organic than machined.
AC45 vs. AC72
The AC45 is essentially a practice boat for the main craft—the bigger, faster, even less-forgiving AC73
| Height | Width | Length | Weight | Area of Wing | Size of Crew | Top Speed |
AC45 | 70.5 | 22.6 | 45 | 3,086 | 900 | 5 | 35/40 |
AC72 | 131 | 46 | 72 | 13,000 | 2,750 | 11 | 42/8 |
Illustration: Joel Kimmel
Smyth walks me over to a line of rough plywood cradles holding a glossy, super-elongated basin, pointed at one end and open at the other. A few burly young men are bent over it, sanding down some imperfection. At first I mistake the object for the outer hull of an extreme racing shell, as it could easily fit a team of oarsmen seated in a line. I couldn't be more wrong: It's the leading edge of an AC45 mast. Functionally, the carbon half-tube does double duty as both the front of the wing and its main structural component. "It's actually quite a cunning piece," Smyth says, directing me to look inside.
I see that its curve is only a few layers of carbon fiber thick and almost translucent. That membrane is reinforced by long, thick stringers of "uni"—hundreds of bundles of unidirectional carbon fiber—that run down the middle and both edges. Precision-cut bulkheads of "black aluminum" sheeting reinforce the mast and build out the framework that defines the rest of the wing.
As the Austral winter approaches, the weather in Auckland turns ugly. The chop in the gulf roils, egged on by a gusty, confused wind that blows up to 30 mph. Just before noon, a sputtering rain starts to fall. Though the first race of the World Series is less than four months away, only four of the 10 teams competing—Artemis Racing, Emirates Team New Zealand, and Oracle—have their AC45s. (Oracle actually has two teams and two AC45s, called Oracle Black and Oracle White. Such are the advantages of being the cup's defender.) America's Cup Race Management has a lot to figure out, too: Which course designs will make for the most exciting tournaments? Will the newfangled race-management software work? And what about that umpire-on-a-Jet Ski idea? It's time to get on the water.
The embryonic fleet of five—Artemis, New Zealand, Oracle Black, Oracle White, and the Race Management boat—makes its way from Viaduct Harbor to the Hauraki Gulf for its first-ever day of race testing. Little things start to go wrong almost immediately. The radio transmissions of the two mounted umpires cannot be heard over the engine noise of their Jet Skis. Someone on the Oracle team sits on his boat's race computer and causes it to go haywire. A downwind course marker blows loose. The custom-built course management system, which tracks every mark and race boat via GPS, crashes—repeatedly. But Andy Hindley, Race Management's chief operating officer, just shrugs, smiles, and says, "That's why we're testing, to work the bugs out." Hindley is happy because the AC45s themselves are sailing fast and furious. What they lack in monohull majesty they more than make up for with speed and lots of overtaking action. It's the new league's first scrimmage, and the competition is intense. Not surprisingly, given their experience, the Oracle teams are schooling the rest—winning, winning, winning—until the last race of the day, when everything that can go wrong, does.
The final race starts like the others. A call comes in to Oracle White's UHF radio, which John Kostecki keeps strapped to his chest. "Five minutes to start," he announces from where he stands in the middle of the catamaran. The rest of the crew synchronize their watches while Kostecki bounces across the netting to consult with skipper Spithill. It's a standard windward-leeward course, which runs upwind to a turnaround point and then back down. They decide on a tricky gambit called a port start, which is the sailing equivalent of zigging when everyone else zags. Starting on a port tack means sacrificing the right-of-way advantage: One of the most basic rules of sailing is that boats on a port tack must give way to boats on a starboard tack. It's a close cousin of the rule that says if two cars arrive simultaneously at a stop sign, the driver on the right gets to go first. Starting port means you will likely begin in last place but have a clear lane after that. In a sailing race, starting position is not assigned; you're expected to jockey for position in the "prestart" with the goal of crossing the line at full speed just as the official completes the countdown—and not a second before. "Five … four … three …" his words come in loud and clear over the radio.
The three boats on starboard tack—Oracle Black, Artemis, and New Zealand—have all been picking up speed and are heading straight for the gap between the two buoys that mark the starting line. Oracle White and the Race Management boat are charging from the opposite direction. Because they're on a port tack, they must steer behind the other boats, but the Race Management team edges too close to one of the starboard tacking boats and has to lift its port hull out of the water to avoid crashing into the back of it. It's an impressive trick, a sideways-wheelie worthy of Herbie the Love Bug, but after setting back down on both hulls, the boat starts skittering out of control and threatens to knock into Oracle White.
"Watch out for ACRM," Kostecki calls to Spithill, who's manning the helm. "These guys are going to capsize!"
The Race Management boat manages to stay upright, but just barely. It has lost so much speed and position that it drops out of the race before the contest even technically begins. When the race official calls "Start!" it's New Zealand off the line first, followed by the two other boats on starboard tack, Oracle Black and Artemis. Oracle White is last, but now that Race Management has ditched, it has the right side of the field to itself.
New Zealand's lead lasts only a few seconds before it, too, starts gyrating out of control. Spithill, squinting through the dripping fog, notices it first: "Now look!" he says to Kostecki. "New Zealand hooked the starting pin." Sure enough, squeezed at the gate by Oracle Black and Artemis, New Zealand cut it too close and caught its port rudder on the marker buoy's anchor line. Flopping like a fish on a hook, the boat manages to stay up, but it takes so long to unhook that the team decides to drop out of the race.
Built for Speed
The new design for the America's Cup boat boils down to a rigid wing, two minimalist hulls, and not much else. Hard wings are more efficient than soft sails of the same size, and the barely there hulls are made from ultralight carbon fiber.
1. 1/ The wing on the AC45 is longer than the one on a Boeing 727 but weighs scarcely more than a mast and sail of similar size. Its carbon-fiber skeleton supports a transparent plastic skin.
2. 2/ The twin hulls taper at the top—making them look as though they're upside down. This upper knife edge helps the craft pop back up if the bow gets submerged.
3. 3/ The wing is controlled by three lines. One positions the wing, another fine-tunes its camber (the angle in the wing surface), and the third regulates the amount of twist from top to bottom.
4. 4/ Every boat has a GPS-enabled homing beacon that broadcasts its position so accurately, fouls can be called by the race computer instead of a human official.
5. 5/ The wing gets all the ink, but the AC45 has soft sails, too. One, called a jib, is used to go upwind. Another, called a code zero, is much bigger and is hoisted only for downwind runs.
Illustration: Joel Kimmel
Artemis is still in it, but for all intents and purposes there are only two boats that matter now: It's Oracle versus Oracle, Black versus White, and it's personal. Black is piloted by 49-year-old Russell Coutts, 1984 Olympic gold medalist in sailing, Oracle Racing's CEO, and the winningest cup skipper ever. Spithill, 32, is the prodigy—the youngest skipper ever to win the event when he took the cup for Ellison in 2010.
As White and Black tack to converge at the upwind mark, it looks to the uninitiated eye as if Spithill is about to T-bone his boss. If the boats do collide at a 90-degree angle, they wouldn't exactly crash. Spithill would likely sail right on through Coutts, knifing Oracle Black into several pieces. The carbon fiber in the twin hulls of the AC45 catamaran is less than a millimeter thick and quite brittle. Hit at speed by the wave-slicing prows of another AC45, the ultrathin hull wouldn't have a chance. The sailors call it the can-opener effect.
They don't collide, of course. But the right-of-way rules invite a game of chicken at every turn. Converging just before the upwind turnaround mark, Spithill on Oracle White now has the starboard right-of-way, and he uses it to edge Coutts aside, cutting him off and forcing him to either change course or decelerate. Coutts chooses to step on the brakes, adjusting his wing to dump wind.White, in contrast, steps on the gas: Kostecki decides to deploy a supplementary sail. "Unfurl code zero!"
The code zero is a downwind sail, and by hoisting it just before the mark and unfurling it as they turn, White has moved well in front of Black. Spithill, Kostecki, and the rest of the White crew are hiked out on the windward side of the boat, flying just over the surface of the water to counter the tipping force exerted by the wind.
Fully dialed in, the AC45 is so efficient that it can easily outrun the wind, but the speed comes at a price. "Everything happens much quicker on these boats," Kostecki says, "so when you have one problem, it compounds and creates a million others." The chop in the water causes the boat to pitch fore and aft. Kostecki doesn't think much of it until the hobbyhorse suddenly hits a weird wave. White's twin bows submerge, causing the stern to kick up into the air.
Spithill loses steerage as the stern rises. It's a classic pitchpole tumble, an ass-over-teakettle forward somersault. On the way up, Spithill calls out a warning to his untethered crew: "It looks like this time"—the boat's deck reaches full vertical, tossing Kostecki and Dirk de Ridder, the wing trimmer, into the water—"we're really going"—Spithill's voice is even and calm as the boat pirouettes on her port hull to flop on her side—"all the way …"
The wing, slapping onto the surface of the water, stops the boat from rolling any further. Except for its carbon-fiber-and-Nomex skeleton, the wing is completely hollow: It floats. With a little help, the boat can be righted. And so Spithill and the two others who managed to hold fast keep working—only sideways. The crew furls the code zero, Spithill catches a line from the team's nearby speedboat, and Oracle White is jerked upright in a tremendous burst of sea spray. They're sailing again within five minutes. "Eventually," Kostecki says, "we may be able to capsize the boat, right it, and keep on racing."
But not this time. The crash tore the wing's delicate skin and broke half a dozen ribs up top, which makes rejoining the race pointless, but it's not severe enough to stop Spithill from sailing White back to the harbor under her own power. Indeed, after a single night of bone-setting and surgery inside Oracle's boat shed, the craft races the next day, good as new. Since every AC45 is identical, spare ribs are simply a matter of having Smyth dial up his sonic knife and cut new ones out of a sheet of black aluminum.
Difficult as the AC45s are to sail, it won't be long until the America's Cup teams will move up to the supersize AC72. Its mast is nearly twice as tall as the AC45′s, with at least three times the wing area and thus three times the power. Pete Melvin, a Southern California boat designer and multihull specialist, worked with Oracle to set the AC72′s design parameters, which push the dimensions of the big boat to the very limit of what muscle power alone can control. "Anything larger," he notes, "and you'd need motorized winches" to wind in the lines that adjust the hard sail. The AC72′s wing is longer than the wing of Boeing's massive 747.
The big AC72s will debut in the Louis Vuitton Cup in July 2013, slated for San Francisco Bay—the contest that will determine the challenger for the 2013 America's Cup finale (Oracle gets in for winning last time). Unlike the AC45s, the big boats will not all be identical. They'll be governed by a formula devised by Melvin and Oracle, but within those specifications, anything goes. Wing design will be an especially fertile area for innovation. After all, the more gracefully an airfoil can curve the air that flows around it, the more lift it will generate. You can bet that the wings will get especially complex, with multiple flaps, slots and control arms. Traditional ropes could be replaced with in-wing hydraulics like you would find in a modern jet aircraft. The straight shape of the AC45′s daggerboards (the fins beneath the boat that prevent sideslipping) will give way to curved hydrofoils that provide a measure of lift from below as well as stability.
The AC72s will need all the refinements they can get, because they'll be built to sail even closer to the edge than the AC45. Even though the big boat has roughly three times the power, the platform the wing is mounted on is scarcely twice as wide and only 60 percent longer. "It's going to be a wild ride," says Craig Thompson, CEO of the America's Cup Event Authority. "Accidents are inevitable."
"If we do get a collision, say in the prestart where there's a lot of action," Race Management's Andy Hindley says, "it'll be a car crash at 30 miles per hour—only with no airbags and no seat belts." If a sailor were to lose his grip as an AC72 capsized, he might fall four stories before hitting the water. "Broken bones are likely," Hindley says. Medically trained rescue divers will be on hand to deal with the human carnage.
And the boats? "There is just not a lot of data about wing crashes," Melvin says, adding that the AC45s are, relatively speaking, built to a robust standard. The AC72s, in contrast, will be built to win. They'll be even more high-strung and intolerant of error. "A couple notches faster, a couple notches harder to sail, and so the consequences of getting it wrong will be a couple of notches worse," Melvin says with a laugh.
"That," he adds, "is the idea."
Exciting to sail and exciting to watch? Done and done.
Adam Fisher ( adamcfisher@gmail.com) will be covering the Americas's Cup for Wired until the final event in 2013.
0 comments:
Post a Comment