Utilizing the horological know-how gained from their first GMT watch, the GMT Tourbillon that was launched in 2011 followed by the GMT Black which was first announced in 2014 – Greubel Forsey has created an all-new GMT timepiece. Presumably one of the most luxurious Greenwich Mean Time wristwatches ever created by any watch manufacture.
Introducing the Greubel Forsey GMT Sport, presented in a lightweight 45 mm diameter titanium case with a curved profile, integrated lugs, and an ovoid bezel and sapphire crystal – all designed to hug the wrist ergonomically, and to maximize the visibility of the timekeeping displays and the mechanical components which drive them, without ever needing to flip over the watch (although if you do you’ll be able the city display taking over the entire caseback).
Uniquely, the case appears perfectly round from above, while when viewed from other angles the arched and ovoid shape becomes apparent. The case design is the subject of 4 patents. “The sweeping satin-finished bezel with Greubel Forsey’s values relief engraved on its outer bevel follows this unique case shape. The curved profile of the 45 mm diameter case and ovoid sapphire crystal provide the perfect showcase for an entirely new movement architecture with an arched bridge and inclined gear train,” according to the manufacturer.
Greubel Forsey says the GMT Sport movement was “constructed from scratch” with a suspended arched bridge for the hours and minutes display, an inclined gear train, a 24-second tourbillon, and a universal time display with the company’s signature three-dimensional globe. The manually wound movement has 435 total components including titanium plates and bridges, and are finished to the industry’s highest standards.
As with the movement, the functions of this GMT watch are quite a bit more complex than your typical GMT watch. There’s a GMT (2nd-time zone), rotating globe with universal time and day-and-night indication, summer and winter time indication, as well as an indication of cities observing summer time, pushers which control the GMT and Earth displays, a 24-seconds tourbillon, hours, minutes, small seconds, and power reserve.
The hours and minutes hands are skeletonized with oversized arrow-shaped tips, filled with lume, and curved with the curvature of the case and movement. The gear train is mounted on the suspended arching center bridge (which has black finished openings), and the gear train follows the curve of the bridge.
Between 10 and 11 o’clock a subdial with a co-axial display featuring small seconds on a large rotating disc, with a fix red indicator, and the second time zone with a red hand pointing to the hour of a second time zone. A 72-hour power reserve (driven by two coaxial barrels in mounted in series) is indicated by a red, open-worked triangular hand on the readout at 3 o’clock.
At 1 o’clock is a 24-seconds tourbillon mounted on a highly polished tourbillon bridge with black finished openings, which is inclined at 25 ° and completes one full rotation in 24 seconds. “The faster speed combined with the inventive cage inclination, significantly improves chronometric performance in a single-tourbillon system, with minimal movement height,” according to Greubel Forsey. “This exclusive and patented configuration counters the disturbances induced on the movement by earth’s gravity, especially in stable positions. The rotating tourbillon cage housing the regulating organ has 88 components, for a weight of 0.38 grams – a feat made possible in particular by light-alloy pillars and titanium bridges.”
Like the 2011 and 2015 GMT Tourbillon and GMT Black, respectively the GMT Sport features a three-dimensional rotating globe, seen from above the North Pole, and performs each complete anticlockwise turn on its axis in 24 hours. It’s surrounded by a sapphire crystal ring with 24-hour divisions which allows the wearer to read local time for all longitudes, including the day/night indicator (light zone / dark zone). On the caseback side of the GMT Sport, outer and central rings complete the sapphire cities disc to give UTC Universal and Summer Time for 24 cities in major time zones. This disc distinguishes those time zones applying summer time (on a light background) from those that do not (on a dark background). Reviewing the ergonomics, the GMT’s functions use two pushers located on the left side of the case, one to select the second time zone and the other for synchronizing the local time with the globe.
A titanium and rubber crown also controls the adjustment of hours and minutes and winding. Water-resistance is rated to 100 meters. The GMT Sport comes on a black or blue natural rubber strap, with a titanium folding clasp and is limited to just 11 pieces.
Retail is $500,000. Learn more at Greubel Forsey.