IWC Schaffhausen recently introduced a noteworthy timepiece at Watches and Wonders Geneva, the Big Pilot’s Watch Shock Absorber Tourbillon Skeleton XPL, bearing the reference number IW357701. This watch represents a significant step for the brand, as it incorporates their patented SPRIN-g PROTECT® shock absorption technology into a watch featuring the delicate and complex tourbillon mechanism. The combination of high-tech shock resistance with haute horlogerie marks a specific direction in advanced watchmaking, pushing the limits of mechanical durability.
The history of
IWC Schaffhausen itself is rooted in a blend of American industrial ingenuity and Swiss watchmaking tradition. Founded in 1868 by Florentine Ariosto Jones, an American engineer and watchmaker, the company established itself in Schaffhausen, Switzerland, leveraging the Rhine River for hydropower. This unique origin story set IWC apart, fostering an early focus on engineering precision and robust construction alongside traditional craftsmanship. Over its more than 150 years, IWC developed a strong reputation, particularly for its professional instrument watches, including the famed Pilot’s Watches which form the foundation for this new XPL model.
Courtesy of IWC
IWC's legacy isn't just built on tradition; innovation in materials has been a consistent theme. The company was among the pioneers in using titanium and ceramics in watchmaking during the late 20th century. This pursuit of advanced materials continued with the development of Ceratanium®, a proprietary material combining the desirable properties of both titanium and ceramic, which features prominently in the IW357701. This history of marrying robust engineering with cutting-edge materials science provides the context for understanding the ambitious nature of the Shock Absorber Tourbillon Skeleton XPL.
The tourbillon complication represents one of the pinnacles of mechanical watchmaking. Originally conceived by Abraham-Louis
Breguet around 1795 to counteract the effects of gravity on the accuracy of pocket watches (which spent most of their time in a vertical position), the tourbillon involves mounting the escapement – the balance wheel, pallet lever, and escape wheel – inside a rotating cage. This cage typically completes one rotation per minute. While its practical necessity in modern wristwatches (which experience varied positions) is debated, the tourbillon remains a testament to watchmaking skill due to its complexity and the visual appeal of its constant motion.
However, this complexity inherently makes the tourbillon fragile. Comprising dozens of minuscule, lightweight parts working in concert within a very confined space, the mechanism is particularly susceptible to disruption or damage from physical shocks. Protecting such a delicate assembly from significant impacts, while allowing it to function accurately, presents a substantial engineering challenge. This vulnerability is precisely what IWC sought to address with the Big Pilot’s Watch Shock Absorber Tourbillon Skeleton XPL.
Enter IWC’s experimental engineering division, known as XPL. This specialized department focuses on developing technologies to push the boundaries of mechanical watch durability, aiming to create timepieces capable of withstanding extreme conditions. Research into enhanced shock protection is a primary focus. It's understood that impacts, such as dropping a watch onto a hard surface, can subject the case and movement to accelerations ranging from 300 g to well over 1000 g. Mitigating these forces is crucial for protecting the intricate mechanics within.
Courtesy of IWC
The core innovation addressing this challenge is IWC's patented SPRIN-g PROTECT® system, first introduced in 2021. This system employs a cantilever spring, carefully designed to suspend and cushion the entire movement within the watch case. When the watch case experiences an impact, the spring compresses, absorbing a significant portion of the shock energy and drastically reducing the forces transmitted to the movement itself. An integral part of this system is a unique crown coupling mechanism that allows the movement a degree of freedom to move relative to the case when the crown is not engaged for winding or setting.
Adapting this SPRIN-g PROTECT® system for use with a tourbillon movement, specifically the IWC-manufactured 82915 calibre, required a complete re-engineering of the shock-absorbing spring. The initial design had to be modified to accommodate the specific dimensions and mass distribution of the tourbillon calibre. Engineers utilized advanced computer simulation tools to meticulously recalculate the geometry and properties of each of the spring's eight arms, ensuring optimal performance for this specific application.
Following the redesign, the modified shock absorber system underwent extensive and rigorous testing procedures using sophisticated measurement methods. The results of these tests were impressive: IWC reports that tourbillon movements protected by the re-engineered SPRIN-g PROTECT® system successfully withstood shocks generating accelerations in excess of 10,000 g. This level of protection for such a traditionally delicate complication represents a significant advancement in horological engineering and validates the effectiveness of the XPL division's approach.
A critical element enabling this high performance is the material chosen for the cantilever spring: Bulk Metallic Glass (BMG). BMG is not a typical metal. Through a highly complex manufacturing process involving extremely rapid cooling of a liquid metal alloy, BMG achieves an amorphous, or non-crystalline, atomic structure. This disordered internal structure gives the material significantly higher elasticity compared to conventional crystalline metals. This inherent "springiness" is ideal for a shock absorber component designed to deform under load and return to its original shape, efficiently dissipating impact energy. The spring's geometry is also optimized to distribute stress forces evenly across its structure.
Manufacturing BMG consistently is an engineering feat in itself. The rapid cooling necessary to prevent crystallization requires precise control. If the metal cools too slowly, it forms a standard crystalline structure and loses the advantageous elastic properties that make it suitable for the SPRIN-g PROTECT® system. This material science challenge underscores the advanced nature of the technology employed in the watch.
Courtesy of IWC
Another key factor in maximizing the effectiveness of any shock absorption system is minimizing the mass that needs to be protected. Basic physics dictates that for a given impact force, a lighter object will experience less resultant stress. Recognizing this, IWC engineers took a strategic approach to reducing the weight of the IWC-manufactured 82915 calibre. This was achieved through extensive skeletonization.
The plates and bridges, which form the main structure of the movement, were artfully machined to remove excess material, leaving behind a strong yet lightweight framework. Even the automatic winding rotor, typically a solid oscillating weight, was skeletonized. This significant reduction in the movement's overall mass directly enhances the performance of the SPRIN-g PROTECT® system, allowing it to provide greater protection against high g-forces.
Visually, the skeletonization transforms the watch's appearance. Much of the intricate internal mechanism is laid bare, offering captivating views of the gears, levers, and springs at work. This includes a clear view of the BMG shock absorber spring itself, showcasing the technology usually hidden within the case. The overall aesthetic is highly technical and modern, emphasizing the engineering prowess behind the timepiece.
The heart of the watch is the IWC-manufactured Calibre 82915. This is an automatic winding movement, meaning it harnesses the wearer's natural wrist motions to wind the mainspring, eliminating the need for daily manual winding. The movement is composed of 204 individual components and operates with 25 jewels, which serve as low-friction bearings for rotating parts, enhancing longevity and efficiency.
Powering the automatic winding is IWC’s efficient Pellaton winding system. Named after its inventor, Albert Pellaton, IWC's technical director for many decades, this ingenious system uses pawls and an eccentric cam to convert the bidirectional movements of the skeletonized rotor into the unidirectional winding of the mainspring. Key components within this system are reinforced with zirconium oxide ceramic, a material known for its extreme hardness and near-immunity to wear, further contributing to the movement's robustness and long-term reliability.
Courtesy of IWC
When fully wound, the Calibre 82915 provides a substantial power reserve of 80 hours, meaning the watch can run autonomously for over three days off the wrist before needing to be wound again. The movement's balance wheel oscillates at a frequency of 28,800 vibrations per hour (VPH), or 4 Hertz. This relatively high frequency contributes to the watch's timekeeping stability and accuracy, and is a common standard for modern high-performance movements.
Positioned prominently at the 6 o'clock location is the flying minute tourbillon. In a "flying" tourbillon design, the cage is supported only from below, without an upper bridge, creating the illusion that it is floating freely. This enhances the visual spectacle of the rotating mechanism. Despite its visual complexity, the tourbillon cage itself, consisting of 56 parts, is remarkably light, weighing only 0.663 grams. This low mass is crucial both for its timekeeping function and for minimizing its inertia during impacts. The movement also features a hacking tourbillon mechanism, meaning the tourbillon cage stops rotating when the crown is pulled out to set the time, allowing for precise synchronization.
Complementing the skeletonized movement, the dial design is deliberately minimalist to maintain focus on the mechanics. It consists primarily of a black outer ring displaying the minute track and the iconic triangular index flanked by two dots at the 12 o’clock position – a hallmark of IWC Pilot’s Watches. The hands, also adopting the classic Pilot’s Watch shape, are skeletonized as well, reducing visual obstruction of the movement below. For readability in low light, both the hands and the key dial markers are coated with Super-LumiNova®.
The 44.0 mm diameter case, along with the crown, is crafted from IWC's proprietary Ceratanium®. As mentioned earlier, this advanced material starts as a special titanium alloy. Components are machined from this alloy and then subjected to a high-temperature firing process in a kiln. During this firing, a phase transformation occurs on the surface, creating a ceramic layer that bonds intrinsically with the titanium substrate. The result is a material that retains the lightweight feel and structural integrity of titanium but gains the exceptional hardness and scratch resistance characteristic of ceramic. The firing process also imparts a distinct, dark, matte-black metallic finish. Distinctive rubber bumpers are integrated into the sides of the Ceratanium® case, adding another layer of physical protection and contributing to the watch's rugged, technical look. The case measures 13.0 mm in height.
Protecting the dial and movement from the front is a convex sapphire crystal. Sapphire is highly scratch-resistant, second only to diamond in hardness. The crystal features an anti-reflective coating on both sides to minimize glare and maximize clarity, ensuring an unobstructed view of the skeletonized dial and tourbillon. IWC also specifies that the crystal is secured against displacement caused by sudden drops in ambient air pressure, a feature originally developed for the demanding environment of aircraft cockpits. The case back features a see-through sapphire crystal as well, offering another perspective on the intricately finished and skeletonized Calibre 82915 and the SPRIN-g PROTECT system. Despite the complexity and the display back, the watch maintains a water resistance rating of 10 bar, equivalent to approximately 100 meters, making it resistant to splashes and suitable for swimming.
Courtesy of IWC
Completing the ensemble is a black rubber strap featuring a textured, technical pattern that complements the watch's futuristic design. The strap incorporates a black calfskin inlay for added detail and comfort. It measures 22.0 mm at the lugs and is secured to the wrist by a pin buckle made from matching Ceratanium®, ensuring material consistency throughout the watch's exterior components.
The IWC Big Pilot’s Watch Shock Absorber Tourbillon Skeleton XPL (Ref. IW357701) is positioned as a highly exclusive offering within IWC's lineup. Reflecting its complex engineering, advanced materials, haute horlogerie complication, and the groundbreaking shock protection system, the watch carries a price tag of $185,000 USD. Availability is strictly limited, with production capped at only 100 pieces worldwide, making it a rare and sought-after timepiece for collectors interested in the intersection of high-tech durability and traditional watchmaking artistry.
Case: Ceratanium® construction, 44.0 mm diameter, 13.0 mm height. Features convex sapphire crystal (AR coated) secured against pressure drops, see-through sapphire case back, Ceratanium® crown, distinctive side rubber bumpers, and 10 bar water resistance.
Movement: IWC-manufactured Calibre 82915 automatic movement. Features Pellaton winding (ceramic reinforced), 80-hour power reserve, 4 Hz (28,800 VPH) frequency, 25 jewels, 204 components. Skeletonized plates, bridges, rotor. Incorporates a hacking flying minute tourbillon at 6 o'clock (56 parts, 0.663g). Protected by SPRIN-g PROTECT® shock absorber system using a Bulk Metallic Glass spring, tested to withstand forces over 10,000 g.
Dial: Black, skeletonized design. Reduced to an outer ring with minute scale and signature triangle at 12 o'clock. Skeletonized hands coated with Super-LumiNova®. Tourbillon visible at 6 o'clock.
Strap: Black rubber strap with technical pattern and black calfskin inlay. 22.0 mm width. Fastened with a Ceratanium® pin buckle.
Price: $185,000
Reference Number: IW357701
Notes: Limited edition of 100 pieces. Marks the first integration of IWC's SPRIN-g PROTECT® shock absorber with a tourbillon complication. Utilizes advanced materials like Ceratanium® for the case/crown/buckle and Bulk Metallic Glass for the shock absorber spring.