Why the Blancpain Fifty Fathoms, which broke the internet two years ago with its Swatch collab, is the ultimate dive watch

In 2023, Google Trends reported a massive hundred-fold spike in search queries for the term “Fifty Fathoms”. It followed the launch of the Blancpain x Swatch Bioceramic Scuba Fifty Fathoms that led watch enthusiasts and collab hunters around the world to lose their minds collectively. 

That moment was the closest that Blancpain had ever come to shutting down the Internet. It was also a rare moment when the Fifty Fathoms name was once again on everybody’s lips — just like the day it was released in 1953 — because Blancpain and its iconic diver were not exactly household names. 

Blancpain had remained a niche player for decades, even though it always held a cultish allure to collectors of historic watches, specifically, landmark dive watches. 

Marking the 70th anniversary of the Fifty Fathoms, the inaugural Swatch collaboration has propelled the creation onto a trajectory of modern superstardom. 

Once scarcely known apart from the boffins in the watch community, the Blancpain Fifty Fathoms became the latest “discovery” among millennials and Gen Z, who were eager to learn everything there is to know about this curious diver’s watch with a most exotic name.

Full Fathom 50

A fathom in the Imperial system of units is a measure of length equal to six feet. It is not an international standard unit, but historically has been used as a maritime measure of depth. Incidentally, before it came to be standardised as equivalent to six feet, a fathom was defined as the span of a man’s outstretched arms. 

This curiously anachronistic term ultimately made its way into Blancpain’s watchmaking catalogue thanks to the brand’s CEO of the time, Jean-Jacques Fiechter, who was widely known for his passion for open-water diving as well as classic literature. 

He had taken inspiration from a line in The Tempest by Shakespeare: “Full fathom five thy father lies”. As the watch was waterproof to 300ft, or 50 fathoms, Blancpain’s contribution to the world of divers’ watches finally had a name.

And the reason for it: the famous origin story of how the French elite diver unit, Nageurs de Combat, had commissioned from Blancpain a suitable technical diver’s watch. In 1952, two officers of the French Ministry of Defence, Captain Robert Maloubier and Lieutenant Claude Riffaud, were looking for a timekeeping instrument that would stand up to the extreme conditions of underwater missions. 

Options on the market at that time, however prestigious, could not meet those expectations; a French watch company turned them down, and Blancpain rose to the challenge. 

Soon after its debut one year later, the Fifty Fathoms quickly earned a global reputation for reliability and precision underwater, so much so that other elite military diving units adopted it as standard issue. 

The US Navy’s Underwater Demolition Teams and SEALs used specially adapted MIL-SPEC and “Tornek-Rayville” versions during the 1950s and 60s. At the same time, the Germans, Israelis, and Spanish also relied on Blancpain’s robust construction and superior legibility in their operations. 

Over time, the Fifty Fathoms became a symbol of professional-grade dependability, bridging civilian exploration and military excellence. It was particularly renowned for accompanying pioneering scuba divers like Jacques Cousteau on numerous expeditions — and most famously, in the award-winning 1956 documentary The Silent World. 

Truly, outside of the military, there was no more fitting environment to test the watch than on Cousteau’s wrist aboard his boat, The Calypso, used alongside Cousteau’s own invention, the Aqualung.

Peak performance

Fiechter, a diving enthusiast himself, not only understood those requirements thoroughly but could clearly visualise how to turn them from ideas to reality. Manufacturing technology of the early 1950s brought significant advances in synthetic rubber production, stainless steel machining, and luminous compounds.

These were all imperative in the making of a truly modern diver’s watch. Fiechter also implemented additional reinforcements to his design. 

First, a double-sealed case back with a dual o-ring design — the former to block dust and moisture; the latter to resist underwater pressure. Next, a screw-down crown with additional sealing allows the crown to remain watertight even during manipulation. Arguably, the most practical feature for the wearer is the lockable rotating bezel, which clearly and reliably tracks total bottom time. 

All of this was displayed on a luminous, extra-legible dial painted first with radium and then with tritium, which glows fiercely in dim light conditions. An extra-large case, featuring prominent numerals, markers and hands, was also a prerequisite.

And finally, upon the request of Officers Maloubier and Riffaud, a soft-iron inner core was added to protect the movement from magnetic interference, which was an extremely advanced feature for its time.

Another feature that distinguished the Fifty Fathoms from other watches of that time were the use of an automatic movement. Early references used the MILSPEC R 570 based upon an A. Schild AS 1361N caliber, while later models from the 1980s and 90s were powered by the Frederic Piguet Caliber 1315, after Jacques Piguet acquired Blancpain.

By divers, for divers

Today, over 70 years on, Fiechter’s legacy remains ever present at Swatch Group-owned Blancpain, which Marc A. Hayek currently manages. As CEO of the brand since 2002, Hayek is the primary reason why the Fifty Fathoms retains such close connections to the ocean while staying constantly abreast of the latest improvements in dive watch technology. 

An avid diver himself, he made one seminal move in 2003 to establish the Fifty Fathoms as one of Blancpain’s core product pillars. More importantly, he didn’t just replicate watches from the past but interpreted the Fifty Fathoms for a modern audience. 

The 2003 Fifty Fathoms came with an upgraded bezel featuring a curved, scratch-resistant sapphire crystal insert, which boosts legibility while signalling the manufacture’s bold vision with innovative techniques and materials. 

Thereafter, the Fifty Fathoms evolved even further, incorporating additional functions and complications such as a long power reserve, a flyback chronograph (a Blancpain signature) with waterproof pushers, and a flying tourbillon, entrenching the collection within Blancpain’s high horology roots.

Among the most sought-after Fifty Fathoms references today are the MIL-SPEC model of 2020, the 2013 reissued Bathyscaphe, and the latest Bathyscaphe series in coloured ceramic.

Uncharted waters

This year, as Blancpain marks its 290th anniversary, the Fifty Fathoms collection undergoes a subtle but significant expansion that reinforces its heritage while broadening its appeal. 

Its headline move is the introduction of a 38mm version of the Fifty Fathoms Automatique, designed to complement the existing 42mm and 45mm models and create a genuinely inclusive size portfolio. Notably, the new 38mm collection also features pink or black mother-of-pearl dials, targeting those who desire a more compact or ladies-friendly diver’s watch without sacrificing technical credibility.

Alongside this, Blancpain has expanded its Bathyscaphe and Tech lines. The former introduces three models, including a flyback chronograph. The latter features a 45mm titanium reference, which is a wearable variant of its more daring Gombessa-derived watches, complete with a ceramic bezel, 120-hour power reserve via calibre 1315A, and an interchangeable strap system. 

The brand also continues to refine the Automatique 42mm line: Following the titanium and red gold introductions, a polished stainless steel version has joined the permanent collection, offering a more classic finish to the mid-sized option.

And not forgetting its legion of new young fans, Blancpain has also released the latest Green Abyss edition of the Blancpain x Swatch Bioceramic Scuba Fifty Fathoms collection, flaunting a black dial with a dark green hue.

These exceptional timepieces may be hard-pressed to outperform a digital dive computer while out at sea, but to look at them and not feel their emotional beauty and rich heritage would be unfathomable indeed.