Further advancing the art of multi-axis tourbillons, the Master Grande Tradition Gyrotourbillon Westminster Perpétuel features a tourbillon that is significantly smaller than those in the preceding gyrotourbillon timepieces. As a rule, reducing the size of a mechanism also reduces its error tolerance, which is why successful miniaturisation efforts are so highly valued and complex. In creating a smaller tourbillon, Jaeger-LeCoultre has created a truly wearable gyrotourbillon which has 42mm case size, bringing high complication out of the watch safe and onto the wrist for everyday enjoyment. Each models are limited edition of 18 pieces.

Jaeger-LeCoultre was founded in 1833 in the Vallée de Joux, the cradle of complicated Swiss watchmaking. Since then, it has relentlessly pursued innovation in aid of precision timekeeping. One of the first inventions of founder Antoine LeCoultre was the millionometer, the first instrument able to measure the micron. Ambitious and industry-defining innovation, combined with haut-de-gamme finishing and artistry, are honoured traditions at Jaeger-LeCoultre, which has created more than 1,200 watch calibres to date, counts 180 different watchmaking and watch-related skills as part of its in-house expertise, has over 400 registered patents and has revived age-old decorative techniques such as guillochage and grand feu enamelling in its inhouse Métiers Rares atelier. The 2019 Salon International de la Haute Horlogerie will see La Grande Maison present the Master Grande Tradition Gyrotourbillon Westminster Perpétuel, the first multi-axis tourbillon with a constant-force mechanism, Westminster chime and perpetual calendar.

The Westminster chime is familiar to everyone as the famous melody of the Big Ben clock at the Palace of Westminster in London. Its four-phrase melody is composed of four notes played in different sequences and different quantities at each quarter of the hour. The Master Grande Tradition Gyrotourbillon Westminster Perpétuel uses four sets of gongs and hammers to create the Westminster chime to indicate the quarters when the minute repeater is activated, incorporating a complex mechanism that places it at the most prestigious tier of chiming watches.

Besides the multi-axis tourbillon and the minute repeater, which showcases in-house mastery of the most sophisticated complications, it also features the one horological function with the greatest everyday relevance and pragmatic value: The perpetual calendar. As the name suggests, the perpetual calendar is designed to work in perpetuity. It automatically displays the correct date without the need for manual adjustment between months of different lengths. It even takes into account the extra day at the end of February during leap years. The most common configuration of the perpetual calendar mechanism can only be adjusted in one direction, but the Master Grande Tradition Gyrotourbillon Westminster Perpétuel emphasises the experience and convenience of the user, and its date can be adjusted forwards or backwards without harming the movement. The pointer-style date indication further reinforces the precision aspect of the timepiece, as it jumps over the tourbillon aperture in order to provide the best possible view of the visually stunning rotating escapement.

Of utmost importance in any watch movement is the regulating organ, the balance and hairspring assembly that allows a watch to measure time in precise beats. The tourbillon is a chronometric amplifier that can improve the timekeeping performance of a regulator by averaging out its positional errors. The in-house expertise of Jaeger-LeCoultre in tourbillons is

unmatched, extending over a range of rotating escapements from the award-winning classic tourbillon calibre 978, the unbridged flying tourbillon, the various multi-axis Gyrotourbillon watches, the inclined-axis Sphérotoubillon and the groundbreaking flying tourbillon with flying balance in the Master Ultra Thin Minute Repeater Flying Tourbillon.

Along with this unparalleled variety of tourbillons comes an equally profound understanding of hairspring technology, which Jaeger-LeCoultre has developed with its own in-house tools to form the sophisticated spherical hairsprings used in some of its most evolved tourbillon watches.

The Master Grande Tradition Gyrotourbillon Westminster Perpétuel takes this exploration of precision to a new level with its constant-force mechanism. With the inclusion of the constantforce spring remontoir, the focus on precision is expanded far beyond the whirling dimensions of the tourbillon and its precision regulation. The Master Grande Tradition Gyrotourbillon Westminster Perpétuel constant-force mechanism highlights the precision of power delivery in one-minute cycles, the precision of time display in the jumping minutes hand and the precision of the repeater chime.