When Audemars Piguet introduced the Royal Oak in 1972, it didn’t just launch a new watch; it reshaped modern horology. Designed by Gérald Genta, who took the original “Jumbo” and challenged the idea of what a luxury watch could look like by blending design with high-end finishing, the watch gained a bold character. More than five decades later, that same silhouette still defines the brand, proving that true icons endure.

That spirit of evolution lives on in Audemars Piguet’s RD series, the brand’s research-driven platform for technical experimentation. These projects aren’t built around sales targets; they exist to improve movements, rethink architecture, and push performance. From reworking minute repeaters to creating one of the most complex wristwatches in the Code 11.59 Universelle RD#4, the RD line has become AP’s testing ground for what’s possible.

Now comes RD#5. Released to celebrate the brand’s 150th anniversary, the Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph compresses mechanical ambition into a 39mm titanium case just 8.1mm thick. Inside is the newly developed Calibre 8100, measuring only 4mm in height and combining a flying tourbillon with a flyback chronograph, a pairing never before seen in a true Jumbo. Built from 379 components and powered by a platinum peripheral oscillating weight, it delivers at least 72 hours of power reserve while maintaining the clean proportions that define the Royal Oak name.

• Brand: Audemars Piguet
• Model: Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph (RD#5) “150th Anniversary”
• Reference: 26545XT.OO.1240XT.01
• Diameter: 39mm
• Thickness: 8.1mm
• Case Material: Titanium
• Calibre: Calibre 8100
• Power Reserve: 72 Hours
• Water-Resistance: 2 Bars (20 metres, 65 feet)
• Price: Upon Request (Limited Edition – 150 Pieces)

With the Calibre 8100, Audemars Piguet didn’t just make the watch slimmer; it also changed how the chronograph functions. Instead of the usual hammer-and-heart reset system, the brand adopted a rack-and-pinion setup that stores energy as you operate it and releases it when you reset. When you press the pusher, everything returns to zero in one smooth motion. In other words, this method is more efficient, reducing energy loss and removing extra parts that would normally cause friction.

You won’t notice these changes just by looking at the watch, but you will feel them. The chronograph resets almost instantly, and the pushers require much less pressure than you might expect from such a complex watch. The action is crisp and precise, not heavy. It’s a small detail that really stands out when you wear it.

The flying tourbillon has been redesigned as well. It is now slimmer and features a titanium cage with a peripheral drive to manage energy more efficiently. In many complicated watches, the tourbillon can be fragile, but in this model, it is built to manage higher amplitudes and remain stable. From the start, the goal was clear: this watch is technically advanced, yet it is designed for everyday wear, not just for safekeeping. That combination of complexity and durability is what makes the RD#5 so interesting.

Despite everything happening around the industry, Audemars Piguet doesn’t appear to be slowing down. The brand reported a 12 per cent in results during the first eight months of the year compared to the same period last year, and it plans to return to Watches & Wonders in 2026 for the first time since 2019. RD#5 feels like part of that renewed energy — not just another complex watch, but a clear declaration of where the Royal Oak can go next.

Giulio Papi, Director of Watch Conception at Audemars Piguet, states, “The RD#5 brings together all the hallmarks of a refined chronograph: a world-first in the touch-sensitive push-pieces, an instantaneous jump minute counter, remarkable thinness, and meticulously designed ergonomics and legibility.”

And that really is the point. This isn’t complexity just for the sake of it. The lighter pushers, the crisp jump-minute display, and the slim case all make the watch feel practical rather than overwhelming. For something this technical, it’s surprisingly focused on comfort and clarity.

The Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph RD#5 “150th Anniversary” is limited to just 150 pieces worldwide, with pricing available by appointment only. Considering how rare it is — and how much mechanical innovation it packs into that 39mm case — it wouldn’t be surprising if most of them are already spoken for.