Richard Mille RM 21-01 Tourbillon Aerodyne


Richard Mille RM 21-01 Tourbillon Aerodyne

RM 21-01
Tourbillon Aerodyne

Just like armour, this exoskeleton in Carbon TPT® perfectly protects the case, and is firmly held in place by 20 spline screws
La Cote des Montres - April 22nd, 2021

  • Bringing together Carbon TPT® and 5N red gold
  • Baseplate made of Haynes® 214® with blue PVD coating
  • Limited edition of 50 watches

The superlative quality of a Richard Mille watch is in equal measure the architecture and materials it is made of. Naturally, it would be impossible to design watches capable of resisting extreme conditions without using constituents that were themselves created to handle punishing demands.

In capitalising on engineering materials—particularly from the fields of aeronautics and Formula 1—and testing their potential applications in a watch movement or its housing, Richard Mille brings into being watches whose precision, lightness and reliability are intimately bound to the materials employed.

The new RM 21-01 Tourbillon Aerodyne is entirely true to this lineage and draws on the influence of aeronautics.


Toughness to spare


With the RM 21-01, Richard Mille presents a new case design. The complex structure of the case in 5N red gold is reinforced with an exoskeleton in Carbon TPT®, used for the bezel and pillars. This extremely light and durable composite is made by stacking hundreds of layers of carbon fibres thanks to an automated process that rotates 45° between each layer, then heated to 120° in an autoclave before being machined to the nearest micron. Just like armour, these reinforcements perfectly protect the case, and are firmly held in place by 20 spline screws.

The striking appearance of Carbon TPT® layers perfectly complements the gleam of gold and the royal blue honeycombed motif of the baseplate.


A flightworthy instrument


Carbon TPT® is found at the heart of the baseplate, this time combined with an orthorhombic honeycomb structure embodying the concept of air itself and made of HAYNES® 214® with a blue PVD treatment, a first for the brand. This nickel-chromium-aluminium-iron alloy is primarily intended for use in thermal environments exceeding 955°. Optimal resistance to high-temperature oxidation makes this material—which can nonetheless be moulded and assembled by conventional methods—an especially suitable choice for combustion chambers. Consequently, the RM 21-01’s baseplate offers unsurpassed stiffness, an extre-mely low thermal expansion coefficient and exceptional torque resistance, all essential prerequisites for a Richard Mille watch.

For the bridges, Richard Mille’s movements team opted for grade 5 titanium, a biocompatible titanium- aluminium-vanadium alloy used in the aerospace industry that ensures superior rigidity and excellent corrosion resistance. The barrel and tourbillon bridges, consisting of four arms on an openwork circular base edged in gold, are seated in the central crucible of the plate lending them mechanical properties ideally suited to the rotation of these moving parts, while allowing the beauty of the tourbillon to shine through. This calibre is finished with a PVD treatment in 5N red gold to enhance the contrasts created by the case and the character of this flightworthy mechanism.


Mechanical subtleties


The sapphire glass dial provides a flawlessly transparent window into the manual-winding Calibre RM21-01. The power-reserve indicator is placed in lieu of the number at 11 o’clock, while the torque indicator occupies the 1 o’clock position. The latter makes it possible to immediately know the barrel- spring’s tension and thus optimise the movement’s functioning. At 4 o’clock sits the function selector, operated by a pusher integrated into the centre of the crown, which is crafted in Carbon TPT® and 5N red gold with a gasket in the same material as the white rubber bracelet. A simple press suffices to switch from the Neutral (N) position to Winding (W) to Hand-Setting (H).

From the thoroughly meticulous hand finishing of the movement that includes bevelling, polishing, burnishing and chamfering of the components, to the use of innovative and technical materials and the incorporation of a tourbillon to counter the effects of Earth’s gravity, the new RM 21-01 Tourbillon Aerodyne, issued in a limited edition of 50 watches, explores new horizons.


Richard Mille
RM 21-01 Tourbillon Aerodyne

Technical characteristics

Limited edition of 50 pieces.

Calibre RM21-01: manual winding tourbillon movement with hours, minutes, function selector, power-reserve and torque indicators.

Case dimensions: 42.68 x 50.12 x 14.30 mm

Main features


Power reserve: Circa 70 hours (±10%) indicated on the numeric scale at 11 o’clock.

Baseplate in honeycombed orthorhombic HAYNES® 214® with Carbon TPT® core
HAYNES® 214® is a nickel-chromium-aluminium-iron alloy, designed to provide the optimum in high-temperature oxidation resistance for a wrought austenitic material, while at the same time allowing conventional forming and joining. Intended principally for use at temperatures of 955°C and above, 214® alloy exhibits resistance to oxidation that far exceeds that of virtually all conventional heat-resistant wrought alloys at these temperatures.

Combined with a Carbon TPT® core, the honeycombed geometrical pattern of HAYNES® 214® offers unparalleled stiffness, a low thermal expansion coefficient and exceptional torsion resistance.

The orthorhombic baseplate is given a blue PVD treatment to highlight its original construction.

Bridges made of grade 5 titanium: Bridges are crafted of grade 5 titanium, a biocompatible, highly corrosion-resistant and remarkably rigid alloy, which enables the gear train to function effortlessly. The alloy is 90% grade 5 titanium, 6% aluminium and 4% vanadium. This combination further increases the material’s mechanical properties, which explains its frequent use in the aerospace, aeronautics and automotive industries. They are coated with a 5N gold PVD treatment.

The skeletonised baseplate and bridges were subjected to intensive and complete validation tests to optimise their resistance capacities.

Function selector
In a manner similar to a car’s gearbox, a push-button located at the centre of the crown allows one to select the winding, neutral and hand-setting functions with a simple push.
A hand at 4 o’clock displays the selected function.

Torque indicator
Utilising a numeric scale located between 12 and 1 o’clock, the indicator provides a visualisation of the mainspring’s internal tension, allowing optimisation of the movement’s timing. Below 5.3, the spring is too slack; at the other extreme, above 6.5, excessive tension can adversely affect the running of the movement and may even cause damage.

Free-sprung balance with variable inertia
The free-sprung balance offers greater reliability in the event of shocks or movement assembly and disassembly, and also guarantees better chronometric results over time.

Fast-rotating barrel (6 hours per revolution instead of 7.5 hours)
This type of barrel provides the following advantages:
  • The phenomenon of periodic internal mainspring adhesion is significantly diminished, thereby increasing performance.
  • Provision of an excellent mainspring delta curve with an ideal power reserve/performance and regularity ratio.
Barrel pawl with progressive recoil
This device permits an appreciable winding gain (circa 20%), especially during the start of winding. It also promotes the even distribution of the mainspring’s internal tension.

Modular time-setting mechanism on the caseback
Provides the following advantages for longevity and maintenance:
  • Since the component is mounted outside of the movement, the time-setting assembly can be changed without affecting the integrity of the baseplate in the event of a possible defect or during maintenance.
  • The mounting and dismantling of this module from the back does not require the removal of the hands or dial.
Wheel-based time-setting system (back of the movement)
Provides smooth time-setting functions by eliminating engaging friction and replacing it with rolling friction.

Winding-barrel teeth and third-wheel pinion with central involute profile
The central involute profile of the winding barrel teeth and pinion provides an optimal pressure angle of 20°. This promotes effective rotary motion and compensates for possible variations in the engagement of the going train, thus insuring excellent torque transmission with a distinct improvement in performance.

Spline screws in grade 5 titanium for the bridges and case
This permits better control of the torque applied to screws during assembly. These screws are unaffected by physical manipulation during assembly or disassembly and age well.

Other features


  • Movement dimensions: 30.20 x 29.20 mm
  • Thickness: 7.14 mm
  • Tourbillon diameter: 12.30 mm
  • Balance wheel diameter: 10.00 mm
  • Jewels: 27, set in white gold chatons
  • Balance: GLUCYDUR®, 2 arms, 4 setting screws, moment of inertia 10 mg•cm², angle of lift 53°
  • Frequency: 21,600 vph (3 Hz)
  • Balance spring: elinvar by Nivarox®
  • Torque indicator: with reference measurement in
  • Shock protection: KIF Elastor KE 160 B28
  • Barrel shaft: nickel-free Chronifer® (DIN x 46 Cr 13 + S) with the following characteristics:
    stainless – antimagnetic - suitable for tempering

Case made of 5n red gold and carbon TPT®
From the case and dial to each piece of the movement, the design and execution of the watch demonstrate a holistic approach to conception of the movement, case and dial. As a result, everything has been constructed according to extremely rigorous specifications. The casing ring is eliminated, and the movement is fixed to the chassis with four grade 5 titanium screws and silent blocks (ISO SW).

Carbon TPT® is a highly technical material made up of 600 layers of parallel filaments obtained by separating out carbon fibres. The layers, no more than 30 microns thick, are assembled on a dedicated machine, which stacks the layers, varying the orientation of the fibres by 45° between layers and saturated with a black matrix. The composite is then heated to 120°C at a pressure of 6 bars in a kiln similar to that used for the production of aeronautics parts, after which it is ready to be machined at Richard Mille. During this phase, the many layers of Carbon TPT® are revealed, creating random damascene patterns that make each piece unique.

The tripartite case is water resistant to 50 metres, ensured by 2 Nitrile O-ring seals. The case is assembled with 20 spline screws in grade 5 titanium and abrasion-resistant washers in 316L stainless steel.

Interior flange
In microblasted titanium.

In sapphire (thickness: 0.40 mm) with anti-glare treatment (both sides), protected by 8 silicon braces inserted in the upper and lower flanges grooves.

  • Bezel side: In sapphire (1,800 Vickers) with anti-glare treatment (both sides)
    Thickness: 1.50 mm
  • Caseback: In sapphire with anti-glare treatment (both sides)
    Thickness: 1.20 mm at the centre; outer edges 2.04 mm



  • Hand-polished anglage
  • Hand-polished locking sections
  • Sapphire-blasted milled sections
  • Lapped and polished contact points
  • Burnished pivots
Steel parts
  • Sapphire-blasted surfaces
  • Hand-polished anglage
  • Concave chamfering with a diamond tool
  • Circular-finished faces
  • Rhodium plating (before cutting the teeth)
  • Minimal corrections applied to the wheels in order to preserve geometry and performance