With its mechanical movement driving indications of the time and strength of the tides, the lunar cycle, as well as the strength of the currents and the height of the tides, the Admiral’s Cup AC-One 45 Tides watch remains a truly unique complication in the Fine Watchmaking world.
From the dawn of time, the lives of seagoing professionals have been governed by the rhythms of the tides. In most part of the world, they follow a twice-daily lunar cycle, with the tide coming in on average every 12hrs 25 minutes, before receding again. Created in 1993, the CO 277 caliber beating at the heart of the Admiral’s Cup AC-One 45 Tides was specifically designed for these coastal regions. No less than three years of development, conducted in collaboration with the Astronomic Observatory of Geneva and the SHOM (Hydrographic and Oceanographic Services of the French National Navy) based in Brest, were required to create this highly exclusive “tides movement”.
The CO 277 caliber now provides its essential navigation-related indications on an ocean blue dial bearing subdials that are more graphically styled than ever. The Moon, which determines tidal movements, appears at 12 o’clock. When it is full or black (new moon), meaning when it is aligned the Earth and the Sun, the amplitude or strength of the tides – indicated by a dedicated hand on the dial – is at its peak, with a coefficient of between 95 and 120, dipping to between 20 and 45 during the first and last moon quarters.
The 6 o’clock subdial indicates the time of the two next tides in the next 24-hour period. To know whether the tide is rising or ebbing, the user need only consult the counter at 9 o’clock, which also indicates the current strength. The maximum tide intensity is shown when the pointer is on the horizontal red line. The strength of the current declines when the hand moves towards the high and low tides indicator reaching its lowest strength when the hand can align with the vertical white line.
An authentic SHOM-certified precision navigating instrument, the CO 277 caliber beats at the rate of 28,800 vibrations per hour and has a 42-hour power reserve. Also driving a date display at 3 o’clock, it is housed in the 12-sided Admiral’s Cup case entirely worthy of its performances. The latter is made in grade 5 titanium and remarkably light despite its powerful style and generous 45 mm diameter. Its layered structure features blue PVD-treated titanium inserts echoing the color of the dial and the vulcanized rubber strap secured by a folding clasp. Clearly built for adventure, it is water-resistant to 300 meters and fitted with a sapphire back providing an admirable view of the CO 277 movement.