Monday, January 23, 2017

How an obsessive sailor and his fitness trackers supercharged yacht racing

 A-Cat Sailing, Pegasus MotionX, sailing doesn't get better than this: Santa Cruz perfection! 

From Wired by Philippe Kahn

It was an hour before the start of the race, and Philippe Kahn was in a state of panic.
He was sailing straight for the starting line off Point Fermin, just south of Los Angeles, and the hydraulic system on Pegasus, his 50-foot open-format yacht, had just failed.

Kahn was about to embark on the 2009 Transpac, the infamous, century-old sailing race that takes the bold and well-fixed from the Californian coast to the shores of Honolulu.
It’s a voyage through more than 2,500 miles of unsettled seas and gusting winds.
And without hydraulics to control the boat’s stabilizing canting keel, Kahn didn’t have a chance in hell of keeping her upright.

Fifty minutes later, one of the boat’s two hydraulic rams was back up.
It would have to do.
And with just a few more hiccups along the way, the light-handed Pegasus was triumphant.
Kahn and his lone crewmate, Mark “Crusty” Christensen, shattered the transpacific double-handed record with a time of 7 days, 19 hours, 38 minutes and 35 seconds.
The previous record-setters had taken more than 10 days to make the trip in 2001.
So how did Kahn do it, with a partially crippled boat, no less?
By being singularly obsessed with optimization — finding the right crew and the right technology to survive and prosper on the high seas.

 One of the original prototypes for a sleep and motion tracker that Kahn used on his Transpac races. Talia Herman/Wired

By day, 61-year-old Kahn is the CEO of Fullpower Technologies, which builds the motion-sensing technology inside personal trackers like Jawbone Up and Nike FuelBand.
Sailing permeates life at the company, where about a fifth of the staff — including an Olympic competitor — has a background in the sport.
“The ocean lifestyle is my meditation, where I find myself,” says Kahn.

He tries to get on the water for a couple of hours each day, immersing himself in a marine sanctuary he shares with sea otters and whales.
Kahn recruited Christensen, an engineer and decorated offshore sailor, after the 2009 Transpac, and they regularly take a break from the office in the middle of the day to catch the wind at its freshest.
The overlap between worlds goes further: Kahn considers his sailing machines perfect test beds for the sensors that are his livelihood.
To be self-sufficient on the water for seven days or more, every system must be robustly built and perfectly tuned.
Kahn rattles them off: gyroscopes. Electronic flux-gate compasses. Humidity sensors. Pressure sensors. And, of course, satellite navigation.

To make those systems function at the highest level, Kahn doesn’t settle for off-the-shelf components.
In his 2009 bid, Kahn and Christensen worked to modify a system that measures wind direction.
Typically, the constant pitching and rolling of the boat throws off those measurements.
But by using sensors to detect that motion and correct for it, they could get crucially enhanced information about wind conditions.
“We were trying to monitor the sailboat, trying to help us keep it upright and optimized,” says Kahn, “and it turned out that sailing became an incredible practical laboratory.”

Their true secret weapon, however, may have been sleep tracking.
When sailing double-handed, Kahn explains, “there are times when neither one of us can sleep.
We’ll sleep maybe 45 minutes in 24 hours.”
So Kahn started experimenting with biosensors, creating prototype sleep monitors that he wore and tested on his Transpac bids a decade before personal trackers came into prominence.
His prototype appears to have the sophistication of a Tamagotchi: a single white button, a bulky square face of translucent blue plastic that reveals the vibrator and circuit board inside, and a worn navy blue Velcro strap for a wristband.
But underneath the plastic, it has the same functionality as a Jawbone Up, with a three-axis linear accelerometer to keep track of micromovements.
With this roughshod design, Kahn and Christensen figured out how to take 26-minute power naps optimized for each of them, taking turns at the helm while the other slept.
“Part of our success has been because of our ability to manage sleep better than other people,” Kahn says.
Kahn hopes to find a new yacht worthy of the Transpac — above all, he considers that record-setting trip something to be proud of.
But his ambitions of another high-stakes ocean crossing have ebbed at the moment in favor of mastering a different kind of high-performing sailing machine.

 "The ocean lifestyle is my meditation, where I find myself."

His current target: The Nacra F20 carbon, a 20-foot catamaran with hulls designed by Morelli & Melvin, the team that worked on the America’s Cup AC72.
The cat is a feat of engineering and design, a beautiful boat with two sculpted hulls that look as if they could cut butter.
The Nacra features the curved daggerboards rapidly becoming a mainstay of cat sailing.
They increase the boat’s stability, prevent it from getting knocked away from the wind, and provide some lift, allowing the boat to ride higher and encounter less resistance from waves.

 Kahn stands next to a beached catamaran; its two rudders with winglets at the base are visible.
The gate to Kahn’s right opens up into the harbor’s parking lot, so it’s just a quick roll down to the boat ramp to get it into the water.
  Talia Herman/Wired

But as with the equipment aboard his Transpac yacht, Kahn isn’t satisfied with the best of the best.
So he started ripping the Nacra apart.
In his Santa Cruz shop, Kahn’s team has created new daggerboards, replacing the so-called C-foils with L-foils that angle inward to provide controlled lift to the hulls.
They’re the same basic design as those in the AC72.
Without foils, a boat’s speed is limited by the drag of the hulls.
“But once you get the foils out on a cat,” says Kahn, “there’s nothing but a little bit of drag that keeps you from going faster and faster and faster” — up to 30 knots at its fastest so far.
Kahn’s boat is one of the first of its size to try foiling like this.
At Kahn’s home on the docks — built there for easy access to the harbor’s boat ramp — he shows off the foils as Pegasus sits beached on his driveway.
They’re thin, tapered fins with a gently curving S-shape.
At the Pegasus workshop, filled with dripping resin and flying fiberglass, Kahn’s team shapes them by layering sheets of carbon into wooden molds.

That shape has remained largely unchanged, but there’s one more crucial element: the elevator, the bottom to the foil’s “L” that provides that crucial lift.
It attaches to the fin separately, allowing the team to make minute changes that could make all the difference in the boat’s foiling hydrodynamics.

Kahn got his first taste of the water on the coast of France, where he began windsurfing as a 14-year-old.
To see him sailing on his heavily modded cat with Christensen is to see that teenage adrenaline junkie sparring with the wind.
Almost as soon as the boat leaves the harbor, Kahn is off the boat, feet straddling the side of the hull as his body dangles off the edge.
He’s held in place by a trapeze attached to his body harness.
A long tiller extension allows him to steer a sailboat that he technically isn’t even on.
Pointing to the winglets placed perpendicular to the boat’s two normal rudders (another source of lift, along with the foils), Kahn describes his beast as “more like an airplane than a sailboat.”
But that comparison is most apt when the boat gets going in the 12-knot breeze off the coast of Santa Cruz.
Every time the boat hits 11 knots or so, the cat’s stiff, lightweight carbon body rises above the waves, revealing a glimmer of sunlight between the water and the base of the hulls.

The wind isn’t quite as strong as the boat would like it, and ocean swells break over its twin bows, driving the boat back into the water almost as soon as it starts to rise.
But those brief moments, the hulls hovering weightlessly over the water, are mesmerizing.
“I can’t say how cool it is,” says Kahn.
“The feeling is really that of flying.”
The boat’s clearly still in experimental mode.
As Christensen and Kahn leap over the waves, sea water sloshes through roughly hewn holes where the daggerboards pierce the hulls.
Ideally, those holes will be plugged, eliminating the drag from the water inside.
But “that’s the last half of a percent of performance,” says Kahn — and the boat still has plenty of optimization ahead.
Every day it seems a new improvement is made.
After its last race, through California from Richmond to Stockton, the team decided to slightly modify the bearings that orient the foil in its place, allowing for an extra degree or two of range that lets them better tailor the lift to the conditions they’re sailing in.
Right now, the daggerboards are hoisted into place by hand.
Eventually, they’ll have a line attached to more easily put them in place.
Over time, those small refinements will hopefully help team Pegasus dominate in its races like it did in the Transpac.
This week, though, it’s taking on a smaller challenge: Competing for the first time in the casual Wednesday night races out of Santa Cruz Harbor.

Sizing up their competition at the docks, it doesn’t seem quite fair to put this racing machine up against old-school monohulls, dragging their heavy lead keels like a ball and chain.
But Kahn’s in it for the love of sailing, not for the trophies.
The compromise? “We’ll just try to do two laps for every one of theirs.”

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