What is a Flying Tourbillon? A Functional and Aesthetically Complicated Mechanism

The three major complications in mechanical watches are the perpetual calendar, minute repeater, and tourbillon. This time, we will focus on the flying tourbillon, a derivative of the tourbillon that eliminates the bridge on the dial side, making the tourbillon mechanism appear to float. We will explain the concept and introduce some noteworthy models that feature it.

What is a flying tourbillon?

　First, we will explain what a tourbillon and a flying tourbillon are.

The tourbillon was conceived with the goal of improving precision

　Mechanical watches generally keep time by having the balance wheel, which is connected to the bridge by a hairspring, move back and forth at a fixed interval. Because gravity acts on all parts during this process, the direction of the force changes depending on the position of the movement, causing the movement to operate slightly differently. Each brand adjusts their watches to prevent this change in accuracy due to position, but that's another story.

　The tourbillon was invented to mitigate the effects of changes in position. The balance spring and balance wheel, which are susceptible to the effects of gravity, as well as the associated anchor and escape wheel, are housed in a part called a carriage, which rotates once per minute to equalize the effects of gravity. It was invented by Abraham-Louis Breguet and patented in 1801. Due to its complex structure, it was long thought that only a handful of watchmakers could produce it. However, thanks to advances in machining and other technologies, it is now increasingly being adopted, especially in special models from various brands.

The allure of the flying tourbillon

　When a brand adopts a tourbillon in a special model, it is natural that they try to add a distinctive feature to it. There are many different designs, and many of them have unique mechanisms. One of the most well-known derivatives is the flying tourbillon.

　The concept of the flying tourbillon is to make the carriage appear to float, and it has a mechanism that does not have a bridge on the dial side, allowing the viewer to see the precise and dynamic movement of the carriage, which is made up of delicate small parts, without any obstructions.

　Now, in this day and age when smartwatches are popular, there are probably several reasons why people choose mechanical watches. One of them is the joy of seeing how small parts come together to perform a function. From this perspective, there is high demand for flying tourbillons that focus on the "pleasure of viewing," and in my opinion, various companies are working hard to meet this demand.

Breguet "Classic Tourbillon Sideral 7255"

　As mentioned earlier, after watchmaker Abraham-Louis Breguet invented the tourbillon, no practically usable products were mass-produced, but it was Breguet as a watch brand that realized this in 1983. In homage to this history, let us first introduce Breguet's Classique Tourbillon Sideral 7255.

　2025 marks the 250th anniversary of Abraham-Louis Breguet opening his workshop on the Île de la Cité in France in 1775. Many commemorative models have been released to celebrate this occasion, and the Classique Tourbillon Sideral 7255 is one of them. The greatest feature of this model is its design based on a concept known as "mystery," in which the tourbillon carriage appears to be completely floating.

　Many flying tourbillons do not have a bridge on the dial side, but are supported inconspicuously from the case back. In contrast, in this model, the bridge that supports the tourbillon and the parts that support the base on the axis are made of anti-reflective sapphire crystal, and the contact points connecting the gear train and carriage are also hidden by being placed outside the opening at 6 o'clock. This makes the tourbillon mechanism appear to be floating in the air and rotating on its own. In addition, aventurine, which evokes outer space, is used for the dial, further enhancing the floating feeling of the flying tourbillon.

IWC Portuguese Tourbillon Retrograde Chronograph

　Next up is the IWC Portugieser Tourbillon Retrograde Chronograph. The case is made of 18K Armor Gold®, which is harder than conventional 18K gold, and the vibrant color is complemented by a striking black dial.

　In addition to the central hour and minute hands and retrograde date display extending from the center of the dial toward 9 o'clock, it also features a central chronograph second hand and chronograph functions with coaxial 60-minute and 12-hour counters at the 12 o'clock position, as well as the flying tourbillon, the focus of this exhibition, at the 6 o'clock position.

　This model's flying tourbillon incorporates a tourbillon stop mechanism for time adjustment. Because the tourbillon replaces the second hand, this mechanism is equivalent to a second hand stop function, enabling accurate time adjustment. Unlike a typical second hand stop, this mechanism stops not only the balance wheel and escape wheel, but the entire carriage, and must be immediately restarted by the user, necessitating the stability of the stopping mechanism and high operational efficiency of the entire tourbillon.

　In this model, the pallet fork and escape wheel are made of silicon and coated with IWC's exclusive Diamond Shell® technology to reduce friction, improving the movement's efficiency, allowing for smooth stopping and restarting, and providing a power reserve of approximately 68 hours.

H. Moser & Cie. Endeavour Tourbillon Concept Vantablack®

　Next up is the H. Moser & Cie. Endeavour Tourbillon Concept Vantablack®, a watch that builds on the traditions of watchmaking while challenging itself with avant-garde, artistic design. This model is quite challenging even within the H. Moser & Cie. lineup.

　The dial of this watch uses Vantablack, a material that H. Moser & Cie. has used for its dials, which has caused quite a stir. Vantablack is a material made up of carbon nanotubes and a paint made from it, with the ability to absorb almost all light that strikes it - 99.965%. Humans recognize shapes by visually detecting the light that hits and reflects off an object, so when an object is coated with Vantablack, it becomes impossible to recognize it. When faced with Vantablack, it has been said that "it creates the illusion of a space painted black by CG," and its absorption power is truly astonishing.

　The Vantablack dial of this watch has no indices and is designed with only the hour and minute hands and flying tourbillon. The dial opening resembles a hole in a black space, and the cage supported by the case back is housed within, emphasizing the floating feeling. Along with its strangeness, it also strongly conveys that the design is focused on the tourbillon mechanism.

Louis Vuitton Tambour Taiko Spin Time Air Flying Tourbillon

　Next, let's take a look at the Louis Vuitton Spin Time, which was revamped this year. Spin Time, a unique time display format from Louis Vuitton, features 12 cubes (equivalent to indexes) lined up around the outer edge of the dial, one of which flips over depending on the time.

　For this latest update, the base movement was designed in-house by Louis Vuitton, and six variations were announced, one of which is the Tambour Tyco Spin Time Air Flying Tourbillon.

　The outer edge of the dial is boldly skeletonized, and the design of 12 cubes piercing the central disk creates an impact. In the center of the dial, the flying tourbillon, the star of this feature, is located, acting as the second hand, and the minute hand is located in a circle surrounding this carriage.

　While most flying tourbillons feature a concealed mechanism that transmits power to the carriage while still allowing the movement to be seen, this time the mechanism that powers the Spin Time is housed in the same location, creating extremely tight space constraints. Therefore, the two mechanisms are combined in a compact, in-house designed movement.

Ulysse Nardin "Blast Freewheel Maille Chaussure"

　Finally, we will introduce the Ulysse Nardin "Blast Freewheel Maille Chauve" which allows you to view the flying tourbillon from various angles. This model is a variation of the "Blast Freewheel" with a dial made from "Maille Chauve," an alloy of copper, zinc, and nickel. Its appeal lies in its warm silvery hue and unique texture, a metal that develops a beautiful patina over time.

　The greatest feature of the Blast Freewheel is that each part, including the gear train, is arranged three-dimensionally, with a space above the dial. In particular, the flying tourbillon at 6 o'clock has a hidden gear train that is not visible, giving the illusion that it is floating in the air and continuing to rotate even without the transmission of power.

　The case structure is also ingeniously designed to allow the viewer to fully appreciate this mechanism. The saucer-shaped case is combined with a dome-shaped crystal. This allows the extremely three-dimensional arrangement of the mechanism to be viewed from the side. The view is so striking that it feels more like a clock than a wristwatch.

　The flying tourbillon also boasts a unique design. This model is equipped with Ulysse Nardin's proprietary "Ulysse Anchor Constant Escapement," which distributes the shock to the balance wheel evenly, improving operational stability and isochronism even when fluctuations in output energy occur due to changes in the amount of winding of the mainspring. The structure involves a circular frame that secures the anchor, suspended in mid-air by two leaf springs. The leaf springs bend under pressure, but maintain a stable state.