Jaeger-LeCoultre Master Grande Tradition – Flying Tourbillon

　　While featuring three complications: a minute repeater, a flying (floating) tourbillon, and a celestial calendar, the watch alsoJaeger-LeCoultreelegantly merges the latest technology with its brand heritage and traditions.

　　The Flying Tourbillon—A Rotating Hour Hand

　　The Master Grande Tradition Grande Complication is the only high-end timepiece to employ a flying tourbillon to display celestial time. This function is realised through a three-tier complex mechanism beneath the dial: the bottom gear disc rotates once every 24 hours, while a sun symbol on the dial indicates the hours; above this layer lies a blue lacquered disc depicting the Northern Hemisphere night sky, with the flying tourbillon positioned on the very top layer. Under this architecture, the flying tourbillon floats across the star map dial. The tourbillon itself is mounted within a spherical cage, with 8 ruby bearings ensuring its smooth operation, and is connected solely via a train of gears to the barrel on the opposite side of the movement.

　　The flying tourbillon cage features a cantilevered design with support at the base, rather than being held by bridges at both top and bottom. The entire mechanism comprises 73 components, with a diameter of 12.42 millimetres and a thickness of 3.85 millimetres. Crafted from lightweight titanium, the cage is exceptionally minimalist, offering an unobstructed view of the escapement, and is mounted on a lubrication-free ceramic ball bearing. It utilises a 10-millimetre mono-metallic balance wheel with fine-adjustment screws, a Breguet overcoil hairspring with a variable inertia of 11.5 mg cm2, and an oscillation frequency of 4 Hz.

　　The silicon escapement is clearly visible: the balance staff along with the integrated pallet lever and escape wheel. The escape wheel features a novel design for lightness and ease of operation. Both the balance staff and integrated pallet lever adopt a linear design to achieve superior aerodynamic performance. The use of silicon components not only guarantees long-term running accuracy and lubrication-free operation, but also reduces material inertia compared to traditional steel, increasing the overall movement operating efficiency by 15%.

　　Thanks to a unique silicon coating technology, the production of highly complex components has been made possible. Jaeger-LeCoultre's research and development department gathered a wealth of experience over 5 years of development before releasing the world's first lubrication-free watch—the Master Compressor Extreme LAB conceptual tourbillon timepiece.

　　Minute Repeater—A New Sound

　　For chiming the time, this watch possesses another distinctive feature—a masterclass in on-demand acoustic sounding mechanics.

　　The sound of a chiming watch depends on the sound-generating components of the gongs. To achieve the best possible results, Jaeger-LeCoultre invented an entirely new gong, first used in the 2007 Master Minute Repeater model. Crafted from a unique alloy and formed in a single piece, the gong features a square rather than circular cross-section, increasing the surface area in contact with the hammer to improve strike quality and enhance volume.

　　Standard gongs rely on the vibration of the watch case to amplify sound. However, Jaeger-LeCoultre's elite watchmakers adopted a different type of "amplifier"—a patented innovation known as the "crystal gong", which is connected to a layer of metal foil applied beneath the watch's sapphire crystal. This design allows the timepiece to remain water-resistant, as the damping effect of the gaskets is counteracted by the crystal gong, which is a crucial factor for the durability of any watch.

　　Sliding the actuator on the side of the white gold case reveals two constantly striking hammers on the reverse. Watchmakers invented a special mechanism for this, known as the "trébuchet hammer", to refine the chiming sound quality. Unlike traditional hammers, they designed a dual-axis system connected to a mobile arm. When operated, the hammer accelerates to strike the gong, and the mobile arm is released almost simultaneously to help accelerate the hammer's blow. This method harnesses nearly 80% of the striking energy, whereas traditional hammer systems only utilise 10% to 30%.

　　The Movement—A Fusion of Classic Decoration and Modern Materials. The newly designed and manufactured manual-winding 945 movement is the product of traditional watchmaking meeting modern technology: component finishes feature sunburst graining, perlage, Cotes de Soleil or frosted brushing, further accentuating the movement's classic aesthetic. Steel parts are polished and bevelled, fine-adjustment screws are blued, and fixing screws are rhodium-plated. The dial side of this grand complication is even more astonishing, with the rotating tourbillon complementing the high-tech escapement, while the glossy black silicon escapement contrasts sharply with the polished silvery-white Grade 5 titanium tourbillon cage.