Richard Mille frequently operates at the intersection of extreme technical innovation and avant-garde design. The brand consistently challenges conventional watchmaking boundaries, employing materials and concepts often borrowed from high-performance fields like aerospace and Formula 1 racing. Within this framework, the introduction of the RM 75-01 Flying Tourbillon Sapphire presents a significant statement, showcasing not only the mastery of complex mechanisms but also an ambitious exploration into the demanding world of full sapphire case construction. This timepiece is offered in two variations, one encased in subtly tinted blue sapphire and the other in perfectly clear sapphire, both providing an unobstructed view of the mechanical artistry within.
The story of
Richard Mille is relatively young compared to horology's centuries-old maisons, yet its impact has been profound since its inception around the turn of the millennium. Founded on a principle of rejecting compromise, Richard Mille set out to create watches akin to "racing machines on the wrist." This philosophy translated into a focus on performance, shock resistance, lightness, and the use of cutting-edge materials like titanium, Carbon TPT®, and Graf TPT®. The signature tonneau-shaped case quickly became an identifier, offering an ergonomic fit while providing a unique canvas for displaying highly complex, often skeletonized movements. The brand cultivated strong ties with athletes and demanding professions, using these partnerships not just for marketing, but as real-world testbeds for durability and functionality, further cementing its reputation for building robust, high-performance time machines.
Courtesy of Richard Mille
The RM 75-01 Flying Tourbillon Sapphire is conceptualized around the idea of contrasts and balance. It seeks to merge the perceived rigidity and structural complexity of Gothic architecture – think vaulted arches and intricate frameworks – with the smoothness and transparency associated with water. This duality is expressed through both the physical construction and the aesthetic presentation. The watch aims for a sculptural quality, where the transparent case reveals a movement architecture that is both technically dense and visually light, a careful equilibrium between engineering prowess and artistic expression.
Central to the RM 75-01's identity is its case, crafted entirely from sapphire crystal. This is not merely a sapphire crystal over the dial and caseback, but the entire structure – bezel, caseband, and back – is meticulously milled from solid blocks of this challenging material. Sapphire, chemically aluminium oxide, is renowned for its exceptional hardness, registering 2,000 Vickers, making it virtually impervious to scratches from anything short of diamond. Its crystalline structure grants it near-perfect transparency, providing an unparalleled window into the watch's inner workings.
The process of creating a full sapphire case is an exercise in patience and precision. Richard Mille highlights that machining the components for a single RM 75-01 case requires over 1,000 hours. This involves approximately 430 hours dedicated just to pre-forming the rough shapes of the case parts, followed by an additional 350 hours purely for polishing the components to achieve optical perfection. Sapphire's extreme hardness makes it brittle; any minute error during the milling or cutting phases can lead to fractures, rendering the component useless. This high-stakes manufacturing process underscores the commitment required to realize such a design. Furthermore, the front and back bezels receive an anti-glare treatment to minimize reflections and maximize the clarity of the view into the movement.
For the blue sapphire variant, the challenge intensifies. Achieving consistent and desirable color in sapphire involves introducing specific metal oxides into the aluminium oxide crystal structure during its growth. The precise hue and saturation depend critically on the type and concentration of these oxides. Coloured sapphire is exceptionally sensitive to temperature fluctuations and the rate of crystal growth during its formation. Improper conditions can cause the oxides to distribute unevenly, resulting in patchy colour or undesired tones. Growing the crystal too quickly can also lead to colour inconsistencies and the formation of internal bubbles, compromising both the structural integrity and the visual quality. Mastering this process is key to producing the specific translucent blue desired for the RM 75-01.
Courtesy of Richard Mille
Visually, the RM 75-01 makes an immediate impact. The iconic Richard Mille tonneau shape is rendered in near-complete transparency, whether clear or blue-tinted. This allows the complex, multi-layered movement to appear almost suspended within the case boundaries. Light passes through the watch, highlighting the intricate shapes, finishes, and negative spaces of the calibre. The choice of strap colour, such as the seen bright white or light green options, provides a stark, modern contrast to the crystalline case and the metallic tones of the movement, anchoring the ethereal quality of the sapphire with a tangible presence on the wrist. The watch doesn't just show the time; it showcases its own construction and the intricate dance of its components.
At the core of the RM 75-01 beats the Calibre RM75-01, a manual winding movement developed specifically for this transparent environment. It features hours, minutes, and a prominent flying tourbillon, representing a blend of traditional high watchmaking complications with Richard Mille's characteristically modern execution. The design prioritizes an open, airy architecture that complements the sapphire case.
The structural foundation of the movement, its baseplate and bridges, exemplifies the brand's material science focus. These components are fashioned from Grade 5 titanium, an alloy favoured in demanding industries like aerospace and automotive for its high strength-to-weight ratio, excellent corrosion resistance, and biocompatibility. Composed of 90% titanium, 6% aluminium, and 4% vanadium, this alloy provides the rigidity necessary for the precise functioning of the gear train, especially within a highly skeletonized design where material has been strategically removed. Some elements incorporate 5N gold and feature a grey PVD (Physical Vapour Deposition) treatment, adding visual contrast and depth. Each component underwent extensive validation testing to ensure it meets strict strength requirements despite the minimalist structure.
Positioned prominently at the 6 o'clock location is the flying tourbillon. This regulating organ is distinguished by the absence of an upper bridge supporting its rotating cage. This construction technique creates the illusion that the tourbillon is floating freely within the movement, enhancing the sense of weightlessness and providing an unobstructed view of its intricate operation. The tourbillon incorporates a free-sprung balance with variable inertia, adjusted via four small screws on the balance wheel itself rather than a traditional regulator index. This system offers improved stability against shocks and guarantees more consistent timekeeping performance over the long term.
Courtesy of Richard Mille
Complementing the flying tourbillon is a fast-rotating flying barrel, which completes a revolution every 5.2 hours. This rapid rotation helps to significantly reduce the phenomenon of the mainspring sticking to itself internally, leading to smoother power delivery and enhanced performance. It contributes to an optimized power reserve curve, balancing longevity (around 65 hours, ± 10%) with consistent energy output for better timekeeping regularity. Like the tourbillon, the barrel is also a "flying" component, lacking upper bridges.
This deliberate omission of upper supporting bridges for both the tourbillon and the barrel is a key element of the RM 75-01's design philosophy. It maximizes the perception of transparency and volume, allowing the wearer to appreciate the three-dimensional architecture of the movement from various angles. This approach amplifies the skeletonization concept, pushing it towards a truly architectural expression while maintaining the necessary structural integrity and durability.
Even seemingly standard components receive technical optimization. The teeth of the winding barrel and the third-wheel
Pinion employ a central involute profile. This specific gear tooth geometry provides an optimal pressure angle of 20 degrees, which promotes more efficient transfer of energy through the gear train. It helps compensate for tiny variations in gear engagement, ensuring smoother rotary motion and consistently high torque transmission, ultimately contributing to the movement's overall performance and accuracy.
The Calibre RM75-01 operates at a frequency of 3 Hz (21,600 vibrations per hour). Its balance spring is made of Elinvar, an alloy known for its stability across temperature changes. The movement measures 29.71 mm by 20.78 mm with a thickness of 5.45 mm and contains 18 jewels. Shock protection is provided by a KIF Elastor system. Key components like the balance (made of CuBe) and the barrel shaft (nickel-free Chronifer®) are chosen for their specific properties, contributing to the movement's reliability and longevity.
Courtesy of Richard Mille
Defining the upper boundary of the movement space is a distinctive flange, crafted from 5N red gold with polished and microblasted steel markers. Its design draws inspiration from the structural elegance of vaulted arches in Gothic architecture. This monumental flange rests upon pillars made of polished and satin-finished titanium, creating a play of textures and light. Microblasting and satin-finishing on the gold surface contrast with the polished elements, catching light in interesting ways. The index points are filled with SuperLuminova, ensuring legibility in low-light conditions and adding illuminated accents that highlight the movement's depth. Functionally, this flange acts as the crucial link connecting the intricate movement assembly securely to the sapphire case structure.
Looking through the sapphire case, the movement reveals itself as a complex landscape of meticulously finished parts. The grey PVD treatment on some titanium components provides a muted counterpoint to the warmth of the 5N gold elements and the brighter finish of other titanium parts. Gears, levers, springs, and the rotating assemblies of the barrel and tourbillon are layered, creating a sense of mechanical depth that is fully visible thanks to the transparency of the case and the skeletonized nature of the calibre. The architecture is deliberately complex, designed to be visually engaging from every angle.
The watch is presented on an integrated strap, visually appearing to be made of a comfortable and durable rubber material. The straps shown feature colours like a clean, bright white or a vibrant, almost pastel, light green. These colours create a striking contrast with both the clear and blue sapphire cases, adding a contemporary, sporty feel to the otherwise technically focused timepiece. The integrated design ensures a smooth transition from the case lugs to the strap, enhancing the ergonomic profile of the tonneau shape on the wrist.
On the wrist, the RM 75-01 Flying Tourbillon Sapphire undoubtedly makes a statement. While sapphire is dense, the extensive skeletonization of the movement and the use of lightweight titanium likely keep the overall weight manageable. Its visual presence, however, is significant. The transparency draws the eye directly to the intricate mechanics within, while the unique shape and the pop of colour from the strap ensure it stands out. It’s a piece designed to be seen and appreciated for its technical and material innovation.
Courtesy of Richard Mille
As expected from Richard Mille, particularly for a piece involving such extensive sapphire work and complex mechanics, the RM 75-01 Flying Tourbillon Sapphire is produced in limited editions. This exclusivity is inherent to the brand's positioning and the sheer difficulty and time involved in manufacturing components like the full sapphire case and the specialized movement.
Reflecting its complexity, material cost, and limited nature, the Richard Mille RM 75-01 Flying Tourbillon Sapphire is designated as "Price on request." Prospective buyers would need to inquire directly with the brand or authorized retailers. Availability is highly restricted due to the limited production numbers, placing this watch firmly in the category of ultra-exclusive horological creations.
Case: Full sapphire crystal (clear or blue options), tripartite (bezel, caseband, caseback) milled from solid blocks. Over 1000 hours machining time. Water resistant to 30 metres via 2 Nitrile O-ring seals. Assembled with 24 grade 5 titanium spline screws and 316L stainless steel washers. Anti-glare coating on front/back bezels.
Movement: Calibre RM75-01, manual winding. Features flying tourbillon (variable-inertia balance) at 6 o'clock and fast-rotating flying barrel (5.2h rotation). Skeletonized baseplate/bridges in grade 5 titanium, 5N gold, grey PVD treated. Power reserve approx. 65 hours (± 10%). Frequency 3 Hz (21,600 vph). 18 jewels. Dimensions 29.71 x 20.78 x 5.45 mm.
Dial: Upper flange in 5N red gold (microblasted, satin-finished) on titanium pillars, inspired by vaulted arches. Polished/microblasted steel markers. Index points filled with luminous material (SuperLuminova). Connects movement to case.
Strap: Integrated strap (visuals suggest rubber, available in white or light green). Specific material not listed in provided text.
Price: Price on request.
Reference Number: RM 75-01
Notes: Limited editions. Unique combination of flying tourbillon and flying barrel within a full sapphire case. Gothic art and water fluidity thematic inspiration. Grade 5 titanium used extensively in movement and case assembly.