There are tourbillon escapements and then there are multi-axis tourbillon escapements, a far more exotic breed that has, thus far, been daringly produced by only a handful of watchmakers. In a traditional single axis tourbillon, the escapement rotates on its own axis and in one direction, to compensate for any discrepancies caused by gravity on a vertically positioned pocket watch. Placed in wristwatches, its practical purpose is quite redundant because the natural wrist movements provide the same averaging of gravitational errors.
This is where the sophisticated double, triple and quadruple axis tourbillons come in: These multi-axis tourbillons allow the balance wheel to move around in a three-dimensional manner to mitigate the effects of gravity on a wristwatch, regardless of its position. The first double-axis tourbillon was developed by English watchmaker Anthony Randall in 1977 and placed in a carriage clock. It would take 27 years before a similar mechanism was appropriated into a wristwatch — a milestone achieved in 2004, when Jaeger-LeCoultre launched the Gyrotourbillon 1.
It would be the first of a series of four super complicated watches that the manufacture would produce in the next 12 years. Featuring two tourbillon carriages that revolve at different speeds
and at different axes, the Gyrotourbillons proved to run more precisely. While most traditional tourbillon-equipped watches run on a daily rate variation of two to three seconds, the Gyrotourbillon 1 deviated by only a second a day.
It featured an outer aluminium carriage that makes one revolution a minute (like a standard tourbillon), while an internal carriage — positioned around an axis that runs perpendicularly to the outer carriage — rotates every 24 seconds. Although the spherical tourbillon was the star attraction, the watch also featured the time, a power reserve indicator, double retrograde and perpetual date display and the equation of time. Packed with an eight-day power reserve, it took the Le Sentier-based watchmaker six years to develop the piece.
In 2009, with the launch of the Reverso Gyrotourbillon 2, the second-generation Gyrotourbillon was introduced. Devoid of superfluous complications, this watch was an exercise in precision, coming away with a daily variation rate of only 30 seconds a day. To achieve this, a cylindrical balance spring typically found only in marine chronometers replaced the overcoil hairspring on the Gyrotourbillon 1, making this the first wristwatch to be equipped with a shaped hairspring. Its frequency was also increased from 3Hz to 4Hz, to further enhance its isochronous properties. The inner tourbillon carriage also revolved at a quicker rate: Instead of making one turn in 24 seconds, it made one revolution in just 18.75 seconds, ensuring that the balance maintains constant amplitude regardless of the position.
The third Gyrotourbillon, the Master Grande Tradition Gyrotourbillon 3, was launched during the watchmaker’s 180th anniversary in 2013. This time round, the upper bridge of the tourbillon was removed to allow for an unobstructed view of the mechanism; a spherical hairspring was also used for the first time in a wristwatch. Notoriously difficult to produce but mesmerisingly beautiful, spherical hairsprings also promise to deliver better accuracy because of the proximity of the two terminal curves to the axis. Like the first Gyrotourbillon, the outer cage of the tourbillon makes one revolution in a minute, while the inner carriage rotates once every 24 seconds. This watch also featured an instantaneous digital-display chronograph, a revived ancient finishing technique on the mainplate and a new surface treatment on the tourbillon’s aluminium carriage.
This year, as a tribute to the Reverso’s 85th anniversary, the watchmaker revealed the Reverso Tribute Gyrotourbillon, featuring the fourth generation of its in-house developed dual-axis tourbillon mechanism. Measuring 30 percent trimmer than the Gyrotourbillon 2 (the last time the mechanism was presented in a Reverso case), the Reverso Tribute Gyrotourbillon was exceptionally challenging to produce because of the numerous mechanical components needed to fit within a relatively slim case. As a result, the external carriage and traditional axes were removed and replaced with a ball bearing, a hemispherical hairspring (an industry first) was also put in place, as was the new Gyrolab balance wheel, shaped more like the Jaeger-LeCoultre anchor symbol than a traditional “wheel”. These design features eliminate unnecessary heft and imbue the watch with a more transparent and airy feel while also allowing the wearer an unobstructed view into the intricate mechanism. The two carriages of this biaxial flying tourbillon perform an external rotation in one minute and an internal rotation in 12.6 seconds — the fastest yet in all four Gyrotourbillon watches.
True to the spirit of the Reverso, the swivel case reveals two distinct dials: The front features a finely grained white round dial, a day/night indicator and a small seconds display in the form of a graduated and rotating disc. At the back, the same functions are displayed against a beautiful openworked movement that shows off the brand’s skilled artistry.