Quick answer: The Glycine Airman, launched in 1953, was the first pilot's watch built around a 24-hour dial and a lockable rotating 24-hour bezel for tracking a second time zone — a year before Rolex and Pan Am introduced the GMT-Master in 1954. It went on to serve U.S. pilots in Vietnam and flew to space on NASA's Gemini missions, yet it rarely gets the credit Rolex does.
Watch history tends to be told through a handful of famous names. But many of the industry's biggest leaps came from brands that never became household names. Hamilton released the world's first battery-powered electric wristwatch, the Ventura, in 1957. Seiko launched the first quartz wristwatch, the Astron, in 1969. That same year, Heuer, Breitling, Hamilton-Büren and Dubois Dépraz teamed up on one of the first automatic chronograph movements, Caliber 11. These brands moved the whole industry forward. Glycine belongs on that list — and the Airman is the reason.
In 1953, Glycine sales director Samuel W. Glur was flying from Bangkok to Calcutta when he struck up a conversation with the pilot. Some accounts credit British pilot Chat Brown with the suggestion. The message was clear: pilots needed a watch that read time the way aviation does — on a 24-hour clock — and could track GMT, the reference time used in flight planning and radio communication. Glycine patented its 24-hour watch that same year, and the Airman was born.
The Airman came first. Glycine introduced it in 1953, while Rolex developed the GMT-Master with Pan Am and introduced it in 1954, issuing it to the airline's flight crews. The two watches solved the same problem in very different ways:
Purists still debate which counts as the "first GMT." What isn't debatable is that Glycine put a dedicated multi-time-zone pilot's watch on the market first.
Even by today's standards, the original Airman layout is rare. Most GMT watches add an extra hand. The Airman Purist does the opposite: it uses a single 24-hour hour hand, so noon sits at the bottom of the dial and midnight at the top. To track a second time zone, you simply rotate the bezel — in either direction — until it lines up, then lock it with the crown at 4 o'clock so it can't be bumped off in the cockpit. No extra hands, no clutter, just one clever mechanism. Few brands build watches this way even now.
Glycine kept improving the formula. In 1955 it acquired a patent for a hacking-seconds mechanism, letting pilots stop the seconds hand to synchronize watches precisely before a mission.
The Airman earned its reputation where it mattered. U.S. Air Force and Navy pilots bought it privately during the Vietnam War, making it one of the era's most recognizable aviator watches. In 1965, astronaut Pete Conrad wore his personal Airman on Gemini 5, and again in 1966 on Gemini 11. Because the Gemini capsule opened during a spacewalk, Conrad's Airman is credited as the first automatic watch flown in and exposed to outer space.
Today's Airman DC-4 (reference GL0071) takes the Airman's DNA and adapts it for modern wearers. Named after the Douglas DC-4 airliner, it uses a familiar 12-hour dial, an inner 24-hour track, a 24-hour GMT hand and the classic locking bidirectional bezel — letting it track three time zones at once. Inside is Glycine's GL293 automatic, based on the Swiss ETA 2893-2 or Sellita SW330-1, with 42 hours of power reserve. It's a "caller" GMT, meaning the GMT hand jumps in one-hour steps while the local hour hand runs normally. Add a 42mm steel case, sapphire crystal with a date cyclops, a display caseback and 200m water resistance, and you have a serious tool watch.
Across watch forums, Reddit and owner reviews, a few themes come up again and again:
Here's the part that surprises most people: a watch with Gemini spaceflight history and a claim to the first pilot's GMT can be had for less than many fashion watches. Pre-owned Airman DC-4s regularly trade for roughly $600 to $1,100, and Glycine frequently discounts new models well below their list prices. For anyone who wants a genuine piece of aviation history on their wrist, it's one of the best entry points in Swiss watchmaking.
Innovation in watchmaking doesn't always come from the biggest names. Sometimes it comes from a salesman listening to a pilot at 20,000 feet. The Glycine Airman proves that the brands we overlook often shaped the watches we celebrate. Next time someone calls the GMT-Master the original pilot's GMT, you'll know the rest of the story.
The Glycine Airman, launched in 1953, is widely credited as the first pilot's watch designed to track two time zones using a 24-hour dial and rotating 24-hour bezel. Rolex's GMT-Master followed in 1954 and was the first to use a separate 24-hour GMT hand.
Yes. The Airman debuted in 1953, about a year before Rolex and Pan Am introduced the GMT-Master.
The original Airman and today's Purist models do not; they use a single 24-hour hour hand and a locking bezel. Modern GMT models like the Airman DC-4 add a separate 24-hour GMT hand.
The DC-4 is a "caller" or "office" GMT: its 24-hour GMT hand jumps in one-hour increments, while the local hour hand runs normally. A "true" or "flyer" GMT, like the modern Rolex GMT-Master II, lets you jump the local hour hand instead.
Yes. Astronaut Pete Conrad wore his Glycine Airman on NASA's Gemini 5 mission in 1965 and Gemini 11 in 1966.
Pre-owned Airman DC-4 (GL0071) watches typically sell for about $600 to $1,100, depending on condition and whether box and papers are included.
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