Perpetual calendars are undoubtedly an integral part of Audemars Piguet's history, and the Royal Oak has made a strong impact since 1984. With the introduction of the Royal Oak Selfwinding Perpetual Calendar Openworked with the new caliber 7139, AP signals a clear generational change. Released alongside a Code 11.59 counterpart, an exquisite, beautiful watch, this Royal Oak version is the one that feels most decidedly AP… Let's face it, if given the choice, most of us would naturally choose a Royal Oak.
The case and the bracelet
With a diameter of 41 mm and a thickness of only 9.5 mm, the case impresses with its balance. This is a perpetual calendar that feels slimmer and somehow more wearable than previous openwork Royal Oak QPs Ref. 26585. The construction combines lightweight titanium with AP's proprietary Bulk Metallic Glass (BMG), used for the bezel, caseback frame and bracelet studs, already found in the QP Ref. can be seen on the 150th anniversary. 26585XT. The satin titanium contrasts with the highly polished BMG flashes of a liquid-like shine; The combination feels both classy and technical.
On the wrist, the watch feels flatter and flatter than expected thanks to the integrated bracelet and its reduced thickness. The titanium bracelet with BMG rivets is light, fluid and exceptionally well finished, with alternating brushed and polished surfaces reminiscent of the case. When worn, the watch feels solid without being heavy, a “technical” piece and not a precious burden. The improved 50m water resistance reinforces the feeling that this is a perpetual calendar designed to be worn, not handled carefully.
The openwork dial
In the theater, experimental performances often walk a fine line between spectacle and confusion; The same applies to openwork/skeletonized perpetual calendars. AP essentially gets the balance right here. The sapphire dial reveals the caliber 7139 and at the same time offers surprisingly good legibility. There is a visually pleasing depth; The sub-dials for the calendar displays, which have smoked edges, float above the movement without dissolving into it.
The layout follows a logical European order: day at 9 o'clock with an integrated 24-hour display, date at 12, month and leap year at 3 and moon phase at 6. The week numbers are printed on the inclined inner flange, which is a clever use of space. In practice, in addition to the hour and minutes indicated by the luminous-filled rose gold Royal Oak hands, the current week number is easiest to see as it is white on a black flange and indicated by the centrally located hand. On the rest of the QP displays, the small rose gold hands seem a little jumbled, but a slight twist of the wrist ensures that the light hits the surfaces at the right angle, and there you have it: all are readable at a glance. Overall, however, the dial appears calmer, still complex, but not visually disturbing.
The caliber 7139
The new Audemars Piguet Royal Oak Automatic Perpetual Calendar Openworked is powered by Caliber 7139, the openwork evolution of last year's Caliber 7138. Based on the ultra-thin automatic Caliber 7121 of the classic Royal Oak Jumbo, it integrates all perpetual calendar functions in a single layer, drawing on AP's RD#2 research and the RO Perpetual Calendar Ultra-Thin. The movement is 4.1 mm thick, beats at 28,800 vibrations per hour and offers a power reserve of 55 hours.
From a user perspective, the coolest feature is the all-in-one crown system for all functions. No recessed correctors, no tools, no fear, but studying the instructions is highly advisable. There are four crown positions: To enable winding (normal), the middle position is for calendar setting, turning clockwise sets the date, while turning counterclockwise sets the month and leap year. The full extension is used to set the time and correct the day and number of the week clockwise and the moon phase counterclockwise from the special correction position, which is achieved by pushing the crown back one step from the full extension.
Sounds complicated, but the reality is no stress. Additionally, the safety devices are in place and the non-correction zone is marked in red on the 24-hour display within the 9 o'clock subdial. This lightness of staging fundamentally changes the experience, transforming an often fragile ritual into something reassuringly simple, in the best way possible. The finish is classic Audemars Piguet: hand-chamfered bridges with sharp interior angles, satin brushing, circular grain and polished accents. The openwork rotor, barrel bridge and balance bridge take on a rose gold tone, adding a warm color to the otherwise monochromatic movement.
Availability and price
The Audemars Piguet Royal Oak Automatic Perpetual Calendar Openworked 26685XT is available exclusively at Audemars Piguet boutiques. The price is 180,200 CHF without taxes, and production will be severely limited. For more information, visit AudemarsPiguet.com.
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