When writer, director, and adventurer James Cameron reached the beginning of the “deep sea” at a depth of 1,000 meters on March 26, 2012, safely inside his submersible craft Deepsea Challenger, all the remaining light disappeared. But at that point, he hadn’t yet completed one-tenth of his journey. At 10,908 meters, he landed softly on the floor of the Challenger Deep, the deepest point in the ocean, at the bottom of the Mariana Trench. Before the hydraulic arm on the submersible malfunctioned, he was able to collect a sample from the bottom of the sea. The Rolex Deepsea Challenge, a prototype watch that could withstand water pressure to a depth of 15,000 meters, was strapped on the mechanical arm as well as on Cameron’s wrist.
Only two other people had preceded Cameron in this endeavor – in 1960, Jacques Piccard and Don Walsh reached this point with their underwater craft, Trieste. Then, too, an experimental dive watch from Rolex, the Deep Sea Special, was attached to the outside of the pressurized chamber, and it withstood the dive in 1960 as unscathed as the Deepsea Challenge did in 2012.
Neither watch was ever commercially produced. The Deep Sea Special was virtually unwearable because of its enormous 35-mm thickness and domed, semi-spherical crystal above the dial. The second version was considerably smaller. It was based on the innovative case structure introduced in 2008 for the mass-produced Deepsea model, which has pressure resistance to a depth of 3,900 meters.
In 2008, the Deepsea was the most pressure-resistant mechanical commercial watch available. Since then, manufacturers such as Vintage VDB and CX Swiss Military Watch have been making watches that can withstand even greater depths (and Omega’s Seamaster Ultra Deep has since exceeded the Deepsea’s depth record by several precious meters), but they tower over the wearable 18-mm-thick Rolex Deepsea by at least 6 mm and appear clunky.
In 2014, Rolex introduced a special version of this extreme dive watch with a “D-Blue” dial as a tribute to Cameron’s deep dive. Instead of the completely black dial, this watch has a dial that gradually changes color from dark blue to black, the way the ocean gets darker as it becomes deeper. The Deepsea lettering on the dial is the same green color as the paint on Cameron’s submersible. While the standard Deepsea model was not overly popular, demand for the D-Blue has greatly exceeded supply, in spite of its higher price.
Into the Depths
In 2018, Rolex modified both versions of the Deepsea and we tested the D-Blue model. While the most obvious difference is the wider bracelet with its larger folding clasp, overall, the proportions have a more harmonious feel. The bracelet end pieces no longer protrude above the lugs. Another new feature is a tiny Rolex crown placed at the edge of the dial at 6 o’clock between the words “Swiss” and “made.”
Rolex also tinkered with some of the smaller details. the distance between the case and the bezel has been reduced, which limits the amount of dirt that can penetrate into the watch. The round luminous marker on the bezel is also not as tall and is, therefore, less susceptible to damage. The bracelet has been redesigned to be more supple and comfortable.
Producing an extremely pressure-resistant watch is actually not extremely difficult. The thickness of the case walls and the external dimensions can be increased to the point where a watch can be made with very high water resistance. But Rolex did not approach the problem this way. From the beginning, the Deepsea engineers’ goal was to create a wearable watch. They found success using a diameter of 44 mm and a thickness of 18 mm, which is also very comfortable to wear.
This required a completely new redesign of the case structure – resulting in the Rolex-developed and patented “Ringlock System.” The system consists of three elements that absorb pressure: the 5.5-mm-thick sapphire crystal, the 3.28-mm-thick caseback made of Grade 5 titanium and the inner ring of Biodur 108 steel. The system is surrounded by a 904L steel Rolex case. The titanium caseback is not screwed down but is pressed onto the inner ring by a threaded ring made of the same steel as the case.