Facing the biggest timing-related event on his company’s calendar—the 30th anniversary of the Louis Vuitton Cup sailing regatta—Hamdi Chatti, Louis Vuitton’s vice president of watches and jewelry, was profoundly dissatisfied at the way mechanical wristwatches could handle the task. There are only three important facts in the match race deciding which yacht becomes the official challenger in the America’s Cup: how long each boat takes to sail the course and the time difference between the winning and losing teams. In the past, the best mechanical timer for the job was a rattrapante, or a split-seconds chronograph, with two central second hands that can be stopped independently. Chatti, however, wanted a single-button chronograph with three separate dials to display all the essentials simultaneously. He chose this year’s yachting occasion (which took place last July and August in San Francisco) to tap his company’s newly established complicated watchmaking capability, and in the process created an utterly contemporary timepiece: thin, functional, and original.
Since its acquisition of the complication specialist La Fabrique du Temps in 2011, Louis Vuitton has had the services of two of the industry’s finest watchmakers, Michel Navas and Enrico Barbasini, on call. Soon after their arrival, Chatti asked if they could mechanically separate the two rattrapante hands onto two subsidiary dials, and to add a third indication that would show the differential. After months of work, they told him it couldn’t be done. “A split-second is already a complicated watch and works with clutches, friction, and devices that consume energy and disrupt the movement,” Navas explains. “You’re adding complexity to something that is already complex,” elaborates Chatti. “You lose accuracy. There’s a good reason why nobody has ever done a complication beyond the split-second.”
However, that didn’t alter the fact that the Louis Vuitton Cup was on the horizon. To make a chronograph worthy of the anniversary—and capable of timing a match race properly—Navas and Barbasini proposed a totally new approach. “Their idea was to split the complexity by separating the functions,” Chatti recalls. Rather than running three different indications off the same movement, the watch would have three separate chronograph movements, plus a fourth movement for ordinary timekeeping. Press the chronograph button once and the stopwatches for both yachts start. Press it again and the winning yacht’s chronograph stops at the same instant that the chronograph measuring the time difference starts. A third push stops both the timer for the losing vessel and the one measuring the differential. A fourth push resets all three indications. “So the complexity is in the synchronization,” Chatti explains.
The four movements of the Twin Chrono each occupy one quadrant of the mainplate, all of them identically constructed. (“They all have exactly the same gear train and balance wheel,” says Chatti. “If you change anything, it becomes too complex.”) The chronographs are synchronized with a unique column wheel that controls each stopwatch by directly starting and stopping the balance with a levered spring. The springs launch each escapement at full amplitude, but giving them just the right touch requires that a master watchmaker adjust each column wheel by hand. “The column wheels in these watches are 80 percent the same,” Chatti explains. “The 20 percent that we adjust—far less than a millimeter—makes all the difference in terms of performance.”
The use of four separate movements has another advantage. Complications are usually added to a watch by attaching a module, increasing the thickness. Chatti wanted to make the Twin Chrono as thin as possible, because a thinner watch is more comfortable. “I’d rather have one millimeter less thickness and one millimeter more diameter than the other way around,” he says. The split architecture developed by La Fabrique du Temps requires no modules, an approach that Chatti believes will be advantageous to Louis Vuitton well beyond the Twin Chrono. “I believe this is the next level,” he says. “Some watchmakers will have the know-how to make thin movements and others will not.” In the match race of thinness, Team Navas and Barbasini has a blazing head start.
Louis Vuitton, 866.884.8866, www.louisvuitton.com