Introducing: The Audemars Piguet Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph RD#5 Is The Most Jumbo Of Them All

What We Know

Audemars Piguet’s RD series has always been an exercise in pushing modern watchmaking to its limits. It functions purely as an exercise in saying “why not” to seemingly simple yet challenging ideas in watchmaking; the past four entries in the series have sought to dramatically improve various areas in movement development, from minute repeaters to perpetual calendars, among others. When the launch of the Code 11.59 Universelle RD#4 in 2023 tied all of the discoveries from the first three RD projects together in the brand’s most complicated wristwatch, and the dust had settled, I was dying to know what direction Audemars Piguet would take for the next creation in this experimental series.

Now, in possibly the worst-kept secret in the watch community, we have the answer in the new RD#5: a Royal Oak “Jumbo” equipped with both a flying tourbillon and a brand new flyback chronograph movement. Released to commemorate the brand’s milestone 150th anniversary, this new watch features the dimensions of a Jumbo case, with a diameter of 39mm, a thickness of 8.1mm, and a whole lot of complications.

The big focus with the new watch, AP’s Chief Industrial Officer Lucas Raggi tells me, is on the actual innovation in user experience that comes with the RD#5. “Of course it’s a chronograph. But it’s really the exploration of the feeling of the chrono pushers,” he says. The inspiration for the new short-travel, low-force pushers comes from the buttons on smartphones, so the story goes. However, in parallel with the shift towards modern digital devices, the team also explored the chronographs of the past.

“It might surprise you, but a lot of innovation comes from frustration,” he says. “And in this case, frustration came from vintage chronographs in which the sensation on the pusher was wonderfully soft. Maybe they were not so waterproof, with many gaskets, and needed to be adjusted one by one, but we wanted to get that feeling back. So, it all started with what we should do in a chronograph movement to select and control the sensation and force of the pushers, rather than have it be a result of the mechanical construction. So we had to rebuild the whole thing from zero.”

And rebuild they did, as the RD#5 features the brand-new self-winding Calibre 8100, with a radically different architecture to any chronograph movement seen before, all in a compact package of 31.4mm by 4mm. Its most significant change comes in the reimagining of the chronograph zero-reset system, replacing the conventional hammer-and-heart-cam design with a rack-and-pinion system. Each chronograph hand is tied to a particular rack, and when the chronograph runs, the racks store the energy that typically would be lost through friction in a normal caliber. 

For example, when the chronograph’s seconds hand completes a full revolution, the rack disengages with its pinion, releasing the stored energy (like a rubber band) and then starts over again to propel the hand forward. Simultaneously, the stored energy is used to increment the minute counter forward, which is geared to and also drives the hour counter.

This design also enables the flyback and reset to occur with a light press of the pusher, requiring virtually no force. When the pusher is pressed, the racks disengage and return to zero using the energy that was already stored. The reset takes less than 0.15 seconds, partially thanks to chronograph hands and movement components made out of titanium, one of the more challenging materials to machine for parts in a caliber.

Derived from the RD#3 project is the ultra-thin flying tourbillon in the new caliber, which utilizes the same design features, including a titanium cage, flat hairspring, stepped balance arms, and internal timing weights on the balance. Additionally, the crown has been redesigned to enhance its interaction with the keyless system. Rather than physically pulling out the crown to set the time, a push piece in the center of the crown can be depressed, revealing a red indicator that means the crown now adjusts the hours and minutes rather than winding the caliber. Topping this off is the use of a peripheral rotor, the first in a Jumbo, to showcase the new architecture in all its rack-and-pinion glory.

Executed in titanium and Bulk Metallic Glass (BMG), the case retains that seemingly perfect sizing that collectors have come to love. Also sticking with a classic is the dial, in that classic “Bleu Nuit, Nuage 50” color, but the logo is swapped for a generously sized version of the script logo that has graced all of the 150th anniversary limited editions this year. Two chronograph counters are sunken into the dial, with a snailed finish for better legibility. The hour and minute hands are made of white gold, and, as mentioned above, the chronograph hands are made of titanium. Palladium-based Bulk Metallic Glass graces the bezel, bracelet link studs, pushers, and the new crown function-selector. Finally, the caseback features a “1 of 150” engraving to mark the edition.

Made in a run of 150 pieces, the Audemars Piguet Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph RD#5 is priced at CHF 260,000 (excluding VAT).

What We Think

I was lucky enough to see and handle the RD#5 back in February, when I attended Le Brassus for AP’s 150th Anniversary kickoff, although (unfortunately) no photos were allowed. And wow, it has been hard to keep this a secret. In person, as expected, this thing is jaw-dropping, especially through the caseback. Chronograph movements, when done right, are often some of the most visually captivating views to see through an exhibition caseback, and it’s not every day that you get to see a brand new approach to an automatic chronograph. Seeing how flat yet intricate the caliber 8100 appears was something entirely novel.

Although it may be hard to imagine anyone throwing shade at the caliber, the dial side might be a bit more polarizing, especially with the large “Audemars Piguet” in script printed on the petite tapisserie dial. On one hand, the script certainly makes this edition special as a reminder of the milestone year from the brand, but on the other, the script does clash a little bit with this example of Audemars Piguet at its most modern and industrial.

Regardless, the biggest impact of the RD#5 is the cognitive dissonance of it all. It just felt strange in person, like an illusion on the wrist. It was the most bizarre feeling handling the lightness of titanium in a classic Jumbo silhouette, only to look down and see not just the flying tourbillon but two chronograph subdials — not to mention a seconds hand on a Jumbo! The pushers add to that dissonance, with the extremely light force required, as well as not much travel. While some people may find this less reassuring than the tactility of a conventional chronograph, I appreciate the novelty and the technical execution. Visually, the pushers look so well streamlined against the Jumbo case that it’s hard to imagine a chronograph on a Jumbo done any other way. In ultra-thin watchmaking, oftentimes as a caliber gets thinner, it has to get wider. But the RD#5 hits a great balance here. If you can wear a 16202, you can wear this as well.

The RD series is Audemars Piguet at its modern peak, and entries like the RD#5 are a great reminder that the R&D labs at AP Le Brassus and Le Locle (with names like Lucas Raggi, Giulio Papi, and Anne-Gaëlle Quinet involved) are constantly up to really incredible feats of engineering. 

But at the same time, AP just dropped a bombshell fact: the RD#5 will be the last for this line of watches. The announcement marks the end of a decade of ambitious concepts. They will instead focus their efforts on what the brand sees as more practical innovations, targeting the main line with a greater emphasis on serving the majority of its customer base. With the newly announced Fabrication Laboratories, a chapter has concluded for Audemars Piguet, while a new, perhaps less crazy one has just begun. 

The Basics

Brand: Audemars Piguet
Model: Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph
Reference Number: 26545XT.OO.1240XT.01

Diameter: 39mm
Thickness: 8.1mm
Case Material: Titanium and bulk metallic glass (BMG)
Dial Color: “Bleu Nuit, Nuage 50”
Indexes: Applied
Lume: Yes
Water Resistance: 20m
Strap/Bracelet: Titanium and BMG bracelet

The Movement

Caliber: 8100
Functions: Hours, minutes, flyback chronograph, flying tourbillon, crown function-selector
Diameter: 31.4mm
Thickness: 4mm
Power Reserve: 72 hours
Winding: Automatic (peripheral rotor)
Frequency: 21,600 VpH (3 Hz)
Jewels: 44
Additional Features: Column wheel, redesigned vertical clutch system

Pricing & Availability

Price: CHF 260,000
Availability: AP Boutiques
Limited Edition: Yes, 150

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