Review: Omega Seamaster PloProf

‘It may not look pretty on the surface, but deep down it’s beautiful.’ Those aren’t my words—those are Omega’s. The people there tasked with building the brand’s most advanced diver yet knew their watch was no looker, but that didn’t matter. It wasn’t for strutting about with; it was for using. It was the Plongeur Professionnel, the PloProf—the Professional Diver.

Ever heard the expression, ‘necessity is the mother of invention’? That’s where the story of the PloProf starts, with the necessity for a watch that could withstand the crushing depths of the sea. Radical developments in diving equipment that made it quicker, cheaper and easier to get to the ocean floor sparked a development race between watchmakers to build a watch that could handle the immense, crushing pressure of the sea.

This was in the early 1950s; before then, development of waterproof watches had been slow at best. In 1926, Rolex unveiled its first moisture-resistant case, the Oyster, as a demonstration of the brand’s all-purpose capabilities, with Omega following up six years later with the frankly impractical case-within-a-case Marine—but there was nothing that could conceivably be considered a professional tool.

All that changed in 1952, when French naval captain Bob Maloubier, whose elite group of special forces swimmers had been equipped with the latest diving gear, needed a watch that could work to the same extremes as his team. As no such product existed, he cracked out his pen and designed one himself. It had a black dial with big, luminous hour markers, thick, luminous hands, a rotating bezel divided into sixty minutes and a chunky steel case water-resistant to 91.45 metres—or fifty fathoms. Maloubier approached several watchmakers to produce his watch—and was actually turned down by some—before the design found a home with Blancpain.

Of course, Rolex jumped on this new opportunity like a shot, taking the military-only concept of the Blancpain and producing it for hobbyist and pro divers alike a year later. This was the Submariner, what was at the time a bit of a risk for the company, part of a year-on-year rollout of watches for professionals, be they pilots, scientists, drivers, explorers or, in this case, divers. A finger in every pie, so to speak.

Omega, meanwhile, a more established company with a reputation for precision, felt no need to pursue this particular gamble, or at least not until it became apparent how lucrative a business diving was becoming. Never mind the military—exploring the ocean floor was about to go commercial on an enormous scale.

By the time Omega reacted with the Seamaster 300, a complete redesign of an existing model line, it was 1957, just as the 100-metre dive record was set and the Genesis saturation diving project began. The Seamaster 300 boasted a thicker, stronger case, chunky, glowing dial markers and hands, a unidirectional timing bezel with a glowing 12 o'clock marker, and bizarrely, a 200-metre water resistance despite the '300' in the name. Now, finally, Omega had everything it needed to compete with the Submariner—but things were only just getting started.

The race to the bottom of the ocean picked up speed in 1961, when the Compagnie Maritime d'Expertise—the Maritime Expertise Company, or COMEX for short—began experimentation with deep-sea diving. As Chuck Yeager discovered over a decade before in his supersonic flight in the Bell X-1, these unknown extremes posed some alarming problems. It has to be remembered that, at the time, Yuri Gagarin had already become the first man in space, whereas the depths of the ocean had barely been touched.

The issue COMEX was attempting to overcome was an unusual and dangerous one: as pressures rise with increased submersion, the more the tiny particles of nitrogen in the air get forced into the tissue. That's fine so long as the nitrogen remains under pressure, but quick decompression as a person resurfaces can trap the nitrogen in the body with lethal consequences.

COMEX trialled different mixes of breathable gas to eliminate the problem, testing them over periods of time on subjects living in hyperbaric chambers deep below the waves. And the testing was becoming more extreme, depth records falling one after another. It was quickly becoming apparent that the Submariner and Seamaster 300 were no longer tough enough for the job.

This time, Omega jumped straight onto the challenge. COMEX was planning a 1968 hyperbaric box experiment at 610 metres below sea level; that was the benchmark. The watch would be a fresh design, from the ground up—built for the professional diver. A monobloc case, manufactured in one piece at a uniform thickness to prevent stress fractures by eliminating weak points, housed a crystal-sealing technology that compressed for increased resistance the deeper it went, on top of which came a button-locked bezel and a completely recessed crown with locking cap to protect it from knocks.

The Seamaster 600, the PloProf, was a brute. In testing, it not only exceeded its posted 600 metres of water resistance, it annihilated it, reaching 1,370 metres before the crystal had compressed close enough to touch the hands—but the case itself was still watertight. After four years of development, at a price that exceeded every other Omega watch available at the time, the watch was presented to COMEX.

Trouble was, it was too late. The PloProf was released in 1970, two years after the deadline, and while Omega had been developing it, Rolex had simply retrofitted a Submariner case with a thicker bezel, crystal and case back—plus a helium escape valve to prevent the crystal popping off during decompression—slapped the name 'Sea-Dweller' on it and called it a day. It was such a quick turnaround that the company hadn't actually secured the patent for the escape valve in time, and didn’t even bother removing the 'Submariner' branding.

Rolex beat Omega to the punch with its Sea-Dweller by three years. Later versions received a thicker case and a revised water-resistance of 1,220 metres, finally matching the PloProf's impressive capabilities, but it didn't matter, because the Sea-Dweller had already done everything it needed to do. By that point, it was just too late for Omega, and the PloProf went out of production in 1979, never recouping its original development budget.

It's an interesting lesson to learn, even today. Omega, keen to show how advanced it was and how impressive its technology could be, missed out because Rolex had delivered what COMEX needed—and nothing more—on time, on budget. The PlofProf was, and is, an impressive device, far more advanced than the Sea-Dweller in many respects—but that's just no good when it was three years too late.

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