Ulysse Nardin Diver [AIR]

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HIGH HOROLOGY
HIGH TECHNOLOGY
HIGH PERFORMANCE

The first dive watches date all the way back to the 1950s, so it might seem that by now, the limits of what is possible, in terms of innovation, technical creativity, and performance would have been reached. Unless pushing boundaries is part of your DNA.

For the independent Swiss watch manufacturer Ulysse Nardin, limits are meant to be transcended, and for the latest edition of its Diver collection, the brand has gone beyond what is expected and even believed to be possible. Creating the new Diver [AIR], the lightest mechanical dive watch ever made.

High horology, high technology, high performance.

These are the three aspects to know about the Diver [AIR]. Three strengths that, on their own, are already impressive, now together for the first time in history. The Diver [AIR] is the impossible, made possible.

HYBRIDISATION OF A SKELETON AND A SPORT WATCH

Ulysse Nardin ventured into the diving scene much earlier than most, creating its first waterproof instrument in 1893, its first dive watch in 1964, and the Aqua Perpetual, in 2001, the first and only water-resistant dive watch to 200 metres featuring a perpetual calendar.

In 2021, the brand introduced the Diver X Skeleton, a timepiece that revolutionised the industry by combining skeletonisation with a dive watch. In fact, today, many collectors acquire a dive watch as a robust, everyday timepiece that can withstand impact, and they often also add a high horology piece to their collection—a prized jewel worn with care. Ulysse Nardin envisioned a watch that seamlessly combines the best of both worlds.

That was a breakthrough, but this is Ulysse Nardin, and so laurels are definitely not for resting on. To truly make this the ultimate high horology sport watch, it could be even better. Stronger, sleeker—but most importantly, lighter.

Introducing the new Diver [AIR], a skeletonised high horology sport watch designed for the extremes, that is going to have its weight cut in half.

WORLD’S LIGHTEST MECHANICAL DIVE WATCH

For perspective, the Ulysse Nardin Diver 44mm released in 2019 weighs 120.5g, as would be expected for a sturdy, robust dive watch. The Diver X Skeleton from 2021 cuts an impressive 15g off that mass for a total weight of 105.8g, which, considering how much empty space there is inside that skeletonised calibre, demonstrates how much of a challenge cutting back on weight really is. And yet the Diver [AIR] manages to lose an incredible 68.6g from the Diver 44mm and comes in at less than half of the Diver X Skeleton, which seems, frankly, unrealistic.

Here’s how.

Building upon the foundation of the Diver X Skeleton UN-372 movement, Ulysse Nardin developed a new, innovative, high-tech calibre, the UN-374, which had to be entirely rethought and redesigned. To achieve the Diver [AIR]’s exceptionally light weight of just 52g, including the strap, and under 46g without it, material had to be removed from the Diver X Skeleton’s calibre, while ensuring the watch’s reliability and performance remained uncompromised.

To do so, Ulysse Nardin’s designers endeavored to remove material in the movement, to ounterintuitively make it, somehow, even stronger. More robust. As mass was reduced, what was left was also reconfigured to bring further resilience to its structure. This was done by using the slender bridges to form triangles, a rigid shape found in engineering and architecture to resist bending and warping, an expertise Ulysse Nardin has developed for over thirty years since its first skeletonised watch.

Despite the space inside the watch being 80% air and just 20% material (the watch movement), the highly skeletonised calibre UN-374 can withstand an impact of an impressive 5’000g. It has also been tested for general knocks and vibrations, cycling thousands of shocks over several days, and not just in the lab, but in real-world use too, putting the watch through its paces to prove it can be worthy of the Ulysse Nardin name.

A closer look at the new calibre reveals the extent to which Ulysse Nardin has gone to reduce mass without compromising performance. The bridges are barely a few millimeters wide, hollowed out to save even more weight, while the winding rotor has been minimised to the essentials. The mainspring barrel, where the power is stored, has been reconfigured into a flying arrangement to reduce the mass of the top bridge. Material has even been stripped from the barrel itself to lighten it further, bringing the total weight of the calibre down to just 7g—less than half the weight of the already lightweight Diver Skeleton X’s movement. Some components have also been redesigned—not only for optimal performance but to achieve a visual balance that enhances its overall appeal. After all, who doesn’t like a watch that looks as good as it performs?

You may be wondering why Ulysse Nardin chose not to remove the automatic winding mechanism from the Diver [AIR] to reduce weight further. The answer lies in the stringent official standards that a dive watch must meet, with automatic winding being one of those essential criteria. Additionally, the calibre UN-374 boasts an impressive 90-hour power reserve, thanks to its innovative flying barrel. The Diver [AIR] is equipped with two ultralight, elasticated straps in white and orange for comfort, fastened with a scratch closing for added practicality. These straps are easily interchangeable, without the need for any tools, ensuring the watch remains as versatile as it is functional.

HIGH TECHNO -LOGY

DIVER[AIR] : AN INNOVATION LAB

Creating the lightest mechanical dive watch requires more than removing metal. To achieve this, Ulysse Nardin turned to the periodic table, leveraging over 20 years of expertise in high-tech materials, ultimately pushing the UN-374 calibre into record-breaking ultralight territory.

NEXT-GEN MATERIALS

Generally, watch movements are crafted from brass, which has a density of 8.7g/cm³, making it relatively heavy. Aluminium, at 2.7g/cm³, is lighter, but its softness makes it unsuitable for the rigorous demands of a watch movement. Titanium, at 4.5g/cm³, offers a promising balance—being 45% stronger than steel —but it is notoriously difficult to manipulate. It also tends to catch fire during machining, requiring extremely careful and slow processing, which is why it is so rarely used in watch movements. Despite these challenges, Ulysse Nardin chose titanium — both durable and light — for the first time, marking a groundbreaking innovation for the brand.

Ulysse Nardin has also integrated a highly antimagnetic and light silicon escapement, a key component responsible for controlling the watch’s precise timing, that weighs half as much as a standard balance.

But it is not only about the calibre. The new 44mm case also needed a material overhaul to fight for every possible gram of saving, and so a modular construction built from titanium and carbon fibre was chosen. Because if it is good enough for the pinnacles of motorsport and aerospace, it will work for Ulysse Nardin watches, too.

Why modular? Because carbon fibre is not only visually appealing, but it also has an incredibly low density of just 1.8g/cm³, less than a quarter of steel and half of titanium. Since it is also not particularly waterproof, the movement is encased in a titanium middle case, providing it with 200m of water resistance, which is further elevated by the carbon fibre side parts. At that depth, the sapphire glass is subjected to the equivalent of 170kg of weight pressed right on top of it.

INNOVATIVE ECOSYSTEM

Instead of going to the titanium and carbon fibre suppliers, Ulysse Nardin took it several steps further by partnering with market leaders and start-ups to integrate innovative materials into the Diver [AIR] project. This cutting-edge approach to watchmaking was first introduced with the brand’s Diver Net concept watch in 2020.

The titanium used in the Diver [AIR]’s movement and middle case—a premium and rare material—is 90% recycled. For this key high-tech raw material of the watch, Ulysse Nardin partnered with TiFast, a leading titanium producer, and Thyssenkrupp, a global leader specialising in materials, engineering, and technology solutions with expertise in automotive technologies, materials services, and marine systems. TiFast first recovered titanium from the Swiss biomedical industry, recycling it in Tuscany. Thyssenkrupp then processed the recycled titanium with their leading technologies and thermal treatments to enhance its machining and deformation characteristics.

The side parts of the case are made from Nylo®-Foil, a unique blend of 60% Nylo® and 40% carbon fibre, making it even lighter than traditional carbon fibre. The Nylo® is sourced from ocean netting, supplied by Fil & Fab, a French recycling start-up. The carbon fibre, recovered from the world’s fastest IMOCA sailing boats manufactured by CDK Technologies, is painstakingly recycled back into its original fibrous state by Extracthive, a company dedicated to the circular economy. Both the Nylo® and the carbon fibre are then processed by Lavoisier Composites to create the high-tech material now known as Nylo®-Foil.

The luminous bezel insert is forged from CarbonFoil, 100% upcycled carbon fibres from IMOCA boats, chopped and compressed into a marble-like pattern.

Finally, the escapement plays its part in this innovative approach, as it is produced from an upcycled silicon wafer supplied by Sigatec.

Ulysse Nardin Diver [AIR] Technical Specifications

Reference 3743-170-2A/0A – 36’000 CHF (8.1 % VAT) / 38’000 $ (w/o VAT) / 38’400 € (21% VAT) / 33’420 GBP (20% VAT)

Movement

• New UN-374 Manufacture calibre
• Skeleton automatic movement
• Hours, minutes, seconds
• Self-winding system
• Open barrel
• Bridges and main plate in 90% recycled titanium (Thyssenkrupp and TiFast)
• Oversized balance wheel & balance spring in silicon
• Escapement wheel, anchor in upcycled silicon
• 199 components / 21 jewels
• Frequency 3 Hz / oscillations 21’600 V/H

Case

• 44 mm
• Middle case: 90% recycled titanium (Thyssenkrupp and TiFast)
• Side parts: Nylo®-Foil (60% recycled fishing nets Nylo® from Fil & Fab and 40% upcycled carbon fibres from CDK Technologies)
• Concave rotating bezel : CarbonFoil (100% upcycled carbon fibres from CDK Technologies) with a domed sapphire glass
• Height 14.7 mm
• Caseback:
  • 90% recycled titanium (Thyssenkrupp and TiFast)
  • Titanium open mineral glass case back
• 200 metres water resistance

Dial

• Minimal skeleton dial
• Black indexes and hands with white Superluminova®

Strap

• The Diver [AIR] comes with two interchangeable straps:
  • Orange elastic fabric strap with scratch closing
  • White elastic fabric strap with scratch closing
• Compatible with R-STRAP and rubber straps

Weight

• The Diver [AIR] weighs less than 52 grams
• The head of the watch weighs less than 46 grams
• The strap weighs less than 6 grams