ROYAL OAK CALENDAR WATCHES 1983–1996

Astronomical indications appeared right from the very first mechanical timepieces. One need only mention the fabulous Antikythera mechanism created in Greece around 140 BCE, which according to some reconstructions was capable of displaying not only the date of the Egyptian calendar, but also the Greek Olympiads and their correspondence with the calendar years. Other examples include the extraordinary water clock invented by Chinese polymath Su Sung in the 11th century and the Prague astronomical clock, which has been admired since 1410.

The history of so-called "astronomical" complications encompasses countless creations and specialities, including sunrise and sunset times, the equation of time (solar time), and even Easter date indication. However, since the 19th century, the most classic calendar complication in watchmaking is the perpetual calendar. This additional mechanism (or dial) indicates the day, date, month and often the moon phase across a four-year cycle. The mechanism must be set once a century, i.e. in 2100, 2200, 2300, etc. 

In the mid-1970s, three young watchmakers employed by Audemars Piguet – Michel Rochat, a complications watchmaker; Wilfred Berney, founder of the After-Sales Service; and Jean-Daniel Golay, founder of the Technical Office – got together secretly to launch an ambitious project. Concerned by the quartz crisis that was crushing the Swiss watch industry, they suggested reinventing the perpetual calendar to incorporate it within contemporary wristwatches. After months of research, they presented their project to Georges Golay, then General Manager of Audemars Piguet. Surprised, impressed and convinced, he asked for 159 of these timepieces to be produced even before the model was launched, a figure unheard of for an Audemars Piguet complication.

Launched in 1978, Model 5548 is equipped with Calibre 2120/2800, the world's thinnest selfwinding perpetual calendar at the time (3.95 mm). The mechanism consists of two main parts: the 2120 base movement (2.45 mm), whose history is told in a dedicated article, and the 2800 perpetual calendar underdial work (1.5 mm). Designed to be concealed beneath the watch face, this additional mechanism is hand-decorated: brushed and bevelled steel parts, circular-grained baseplate, along with gilded and enamelled moon.

The success exceeded all expectations (see table below). In 15 years, Calibre 2120/2800 was to equip more than 7,000 Audemars Piguet watches, available in more than 110 different models. Nearly 800 of them were even openworked! In its own way, this calibre paved the way for the revival of traditional complications throughout the Swiss watch industry.

On April 5, 1984, the opening day of the Basel Fair, Audemars Piguet announced the launch of the first Royal Oak Perpetual Calendar, Model 25554. The press release was accompanied by a photograph of a steel model with a very refined dial, featuring shiny-rimmed day, date and month indicators. However, the examination of the Production Registers showed that only one 25554 watch was sold in 1984, in December, and that it was in yellow gold. For the historian, such discrepancies between an announcement and its effects stir tremendous curiosity. What happened?

First of all, it should be recalled that in the 1980s, new products were presented only once a year, at the Basel Fair in April. Audemars Piguet's distributors, agents and retailers evaluated the new models, commented on them, and expressed their customers' likely opinion. It was on the basis of the orders received at the show that the Manufacture fine-tuned its production strategy.

It often happened that the new models unveiled at Basel only existed in the form of prototypes, or even mock-ups. Some were never produced. There is good reason to believe that the water-resistance of the 25554 model still required some adjustments. Indeed, on May 23, 1984, Kurt Meis, the brand's German agent, sent an alarmed Telex to Le Brassus: "This watch is sporty and if it is not water-resistant, we can really 'drop it’.” Message received and approved. The case was reworked and the watchmakers did their utmost to solve the difficult equation of its water resistance, whose weak points remained the calendar correctors and the crown.

Meanwhile, Georges Golay was preparing the future of the brand in Italy. 

As the steel variant of Model 25554 was reserved for the future Italian agent (whose contract began in January 1985), a yellow gold version was introduced in the Audemars Piguet catalogue in July 1984.

The illustration of the watch is accompanied by the following sentence: "At Audemars Piguet, we believe this represents the last word in watchmaking". Advertising executive Heinz Heimann was not wrong when he stated that the Royal Oak Perpetual Calendar embodies excellence in watchmaking miniaturisation, contemporary design, decoration and undoubtedly also elegance. Nonetheless, the future would show that this was clearly not the last word from the collection...

Following the emergence of wristwatches in the early 20th century, devotees of fine watchmaking had to come to terms with the fact that they could no longer admire the mechanical movements fitted inside their watches. Hidden under a dial, protected by a case that was increasingly water-resistant, these technical and decorative marvels could only be seen by the watchmakers who opened the watches.

However, with the arrival of quartz watches, the presentation of the mechanism became a major issue. Revealing the movement not only highlighted the intrinsic value of the watch, but also celebrated the work of the artisans and placed the timepiece firmly within the lineage of the grand watchmaking tradition. The article dedicated to the birth of Calibre 2120 tells how a few watchmakers decided to reintroduce the art of openworking at Audemars Piguet during the winter of 1972–1973.

It was not until 1986 that the very first Royal Oak with a fully openworked calibre appeared. Model 25636 with perpetual calendar then embodied the quintessence of traditional expertise. It combined openworking, engraving, the art of complications and miniaturisation with the contemporary design of the Royal Oak.

More than 200 hours were required for the finest artisans to openwork and engrave a Calibre 2120/2800. When one considers that no less than 313 Model 25636 watches were produced in ten years, alongside other openworked watches, it is easy to understand that Régis Meylan's workshop had plenty to keep it busy.

The enthusiast will particularly admire the extreme refinement of the oscillating weight, the openworking and engraving of the bridges, or the perfect chamfering of all the steel parts. To make these elements visible, the caseback is transparent for the first time and the dial is in sapphire. As for the hands, following the example of the other perpetual calendar models, they are mostly devoid of luminescent material and distinguish the calendar functions (blued steel) from those of the hours (polished gold).

In the Audemars Piguet distribution archives, the description of the dial of each watch was gradually introduced from 1995 onwards and was definitively imposed in 2005. For earlier periods, it is sometimes difficult, if not impossible, to know for sure which dial equipped which watch on the day it left Le Brassus.

Royal Oak Perpetual Calendar watches offer fine examples of the artisanal practices of the time. The same dial plate could be finished in many different ways: colour, finishes, transfers... Moreover, the same dial reference could vary significantly according to the inspiration and skill of the artisan in charge. Moreover, a dial could be used on several different models, sometimes belonging to different collections. For example, the opaline gold dial can be found on the Royal Oak 25554BA, on the round watches 25550BA or 25557BA, as well as on the Royal Oak 25654BA and even 25686BA.

Let's take another example: the chased "Tuscany Blue" dial. To create this little masterpiece, the engraver finely chased a brass plate identical to the one used for many other models. With the help of scorpers and other dedicated tools, he hollowed out and pushed back the material to create a decoration which appears chaotic when viewed under a microscope, yet forms a refined and harmonious whole. The plate was then immersed in galvanic baths to coat the "Tuscany Blue", or "Blue No. 7".

“Tuscany Blue" chased dials for perpetual calendar models were produced from the early 1980s for round watches, including the 5561PT and 5568. It was not until the early 1990s that they were included in the Royal Oak collection, in Model 25654PT, then 25686SP in 1994. From 1995 onwards, certain platinum examples of the Royal Oak Jubilee 14802 were fitted with "Tuscany Blue" dials, but this time without the perpetual calendar.

In 1978, in order to reduce the thickness of the mechanism, the designers of Calibre 2120/2800 chose not to equip it with a leap-year indicator, even though Audemars Piguet had played a pioneering role in this field in 1955. Gradually, however, the need for an annual marker to set the watch became more pressing. Audemars Piguet took the plunge in 1996 with Calibre 2120/2802. The story written since 1996 is a substantial field of interest that will require further lengthy and fascinating research. However, to give you a taste of it, let us recall a few milestones that have marked this eventful history.

Two models dominate the first period: the Royal Oak 25820 and its openworked variant Model 25829, of which more than 2,000 were produced and sold between 1996 and 2013. Other creations deserve a mention, notably the Royal Oak Jubilee 20th Anniversary 25810OR and its peripheral 52-week indication; the ladies’ Royal Oak Perpetual Calendar 33 mm Model 25800 (1996), then Model 25932. Other specialities include the annual calendar introduced in 1999 (25920), and the equation of time in 2010 in the Royal Oak Model 26603.

Despite this creativity and the last-minute rescue of Calibre 2120 at the dawn of the new millennium, customer interest in Royal Oak calendar watches was slowly waning. In the course of 2012, the Royal Oak’s 40th anniversary year, only 13 openworked Model 25829 timepieces were sold. No openworked Model 25820 variant had left Le Brassus for three years! The Royal Oak Perpetual Calendar was running out of steam. The teams remember with nostalgia the heyday during which Audemars Piguet 500 perpetual calendars per year! For many, the page had been definitively turned.

Nonetheless, François-Henry Bennahmias, who took the reins of the company in 2012, strongly believed that it still had a future. In 2015, the watchmakers presented a new-generation calibre, still based on the 2120, named 5134. It was used to equip the Royal Oak 26574, which featured a revisited, dynamic aesthetic. The markets were abuzz and to mark this launch, a brochure entitled Audemars Piguet Calendar Watches told the story of the brand's calendars. It was followed in 2018 by the book titled Audemars Piguet 20th Century Complicated Wristwatches. While these publications fuelled collectors’ interest, the highlight of this revival took place in 2017, with the launch of the Royal Oak Perpetual Calendar 26579CE in black ceramic. From then on, there could be no doubt that the renaissance was going to happen – and its success would surpass anything previous.

At the same time, the perpetual calendar mechanism was thoroughly revisited, leading in 2018 to the Royal Oak Selfwinding Perpetual Ultra-Thin RD#2 (6.3 mm). At just 2.89 mm thick, its Calibre 5133 broke the thinness record previously held for 40 years by Calibre 2120/2800 (3.95 mm). This was more than just a record and revealed a newly emerging approach to mechanical architecture.