Since it launched in 2015, Audemars Piguet’s RD (Research & Development) series has been a way for the luxury Swiss brand to go beyond expectations and even subvert watchmaking norms. In the past we’ve seen audacious models such as a 6.3mm Royal Oak with an automatic perpetual calendar (the world’s thinnest) and a Code 11.59 with a whopping 23 complications.
Falling in line with AP’s 150th anniversary, the 5th in the RD series revisits the Royal Oak “Jumbo” Extra-Thin and won’t be as headline-grabbing as some of its progenitors, but that doesn’t mean it’s not arguably the most noteworthy of the bunch.
Rethinking the Reset
While the classic Bleu Nuit dial with petite tapisserie pattern looks like your classic Royal Oak, the real story here is what’s happening under the hood. Chronographs have relied on the same hammer-and-heart-cam reset system for over a century — functional but requiring a lot of force. AP scrapped that entirely for the new in-house Calibre 8100, replacing it with a rack-and-pinion mechanism that stores energy while the chronograph runs. When you hit reset, that stored energy gets released, snapping the hands back to zero in under 0.15 seconds. It’s fast enough to feel instantaneous.
This redesign allowed AP to reduce pusher travel to about 0.3mm (from the typical 1mm-plus) and drop activation force to around 300g — roughly 10 to 25 times less than most chronographs. By design, the tactile feedback is closer to a smartphone button than a traditional watch pusher, which might take some getting used to but should eliminate the stiff, labor-intensive clicks we’ve come to accept as normal on some chronos.
The movement also features an instantaneous minute jump, meaning the minute counter advances in a single snap rather than dragging or semi-jumping.
Jumbo Proportions, Double Complications
Despite housing both a flyback chronograph and a flying tourbillon — a first for the Royal Oak “Jumbo” — the RD#5 maintains the iconic 39mm case size with 8.1mm thickness. AP achieved this partly through adroit use of “glass box” sapphire crystals that are flat on the outside but hollowed on the inside to clear the hand stack and rotor. The movement itself uses a peripheral rotor in platinum, which keeps the center open and showcases the chronograph architecture.
The case and bracelet combine titanium with AP’s proprietary Bulk Metallic Glass (BMG), a palladium-based alloy that’s scratch-resistant and lightweight. The bezel, pushers, and select bracelet elements use BMG, while the rest is brushed and polished titanium.
The End of an Era
Unfortunately, AP confirmed the RD#5 will be the last in the series. After a decade of moonshot projects, the brand is shifting focus toward more practical innovations aimed at its broader customer base. That makes this final RD release feel less like the swan song it should be.
Spec Sheet
Model: Royal Oak “Jumbo” Extra-Thin Selfwinding Flying Tourbillon Chronograph RD#5
Case Size: 39mm
Case Thickness: 8.1mm
Case Material: Titanium and BMG
Movement: In-house Calibre 8100 automatic
Functions: Flyback chronograph, flying tourbillon, hours, minutes
Water Resistance: 20m
Band: Titanium and BMG bracelet
Limited Edition: 150 pieces
Pricing & Availability
The Audemars Piguet Royal Oak “Jumbo” Extra-Thin Chronograph RD#5 is limited to 150 pieces and priced at CHF 260,000 (~$325,930). It’s available now through AP boutiques.
Recap
Audemars Piguet Royal Oak “Jumbo” Extra-Thin Chronograph RD#5
AP just dropped the final watch in their RD series—a Royal Oak “Jumbo” chronograph with pushers that require 10-25x less force than typical chronographs, thanks to a completely redesigned rack-and-pinion reset system that feels more like tapping a button on your phone.
