Ferdinand Berthoud Chronomètre FB 2TV.1: Engineering the Inverted Movement and Flying Tourbillon

Ferdinand Berthoud’s Chronomètre FB 2TV.1, introduced at Watches & Wonders 2026, is the first reference in the brand’s new Mesure du Temps 1787 collection. It marks the opening of FB’s second decade under Chopard Co-President Karl-Friedrich Scheufele, and it does so by inverting the movement — placing the fusee-and-chain, the flying tourbillon, and the power reserve cone on the dial side rather than concealing them beneath a conventional plate. That single architectural decision cascades into a set of finishing and tolerance demands that differ substantially from anything in FB’s previous output.

The Chain: 465 Links, 311 Pins, 279 mm

The fusee chain in the FB 2TV.1 runs to 279 mm in length, assembled from 465 stamped links and 311 pins. To put that in context, that is nearly double the chain length used in A. Lange & Söhne’s Pour le Mérite watches. Every link must be stamped to consistent geometry and every pin must seat without play, because any dimensional variance in a chain this long accumulates into positional error at the fusee cone. The tolerances involved are not theoretical — a chain that binds or skips under load defeats the entire purpose of the fusee, which is to deliver constant torque to the escapement regardless of mainspring state.

Like Lange’s fusee-equipped calibres, the FB 2TV.1 uses a differential system for its maintaining power rather than a Harrison-style arrangement. The practical effect at the winding crown is a tactile, progressive feel that practitioners familiar with Lange’s Pour le Mérite will recognise. FB has also improved winding efficiency relative to its earlier chain-and-fusee references: the FB 2TV.1 requires ten fewer turns of the crown to reach full wind. That reduction implies either a revised cone geometry, a change in the mainspring specification, or both — the source of the gain matters less than the fact that it was engineered deliberately rather than accepted as a fixed constraint.

The Flying Tourbillon: First for the Brand

The flying tourbillon in the FB 2TV.1 is the first FB has produced. Its placement on the dial side is commercially logical — a tourbillon visible without removing the caseback reaches a wider audience — but it also imposes stricter finishing requirements on every surface of the cage, since all of it is permanently in view. The three-armed cage carries an 11.2 mm free-sprung balance wheel oscillating on an overcoil hairspring. That balance diameter is large by any standard for a wristwatch tourbillon, and the cage itself is terraced in profile to accommodate the height of the overcoil. Machining a terraced cage to the tolerances required for a flying tourbillon — one that runs without an upper bearing, relying on the lower pivot alone — demands that the cage’s mass distribution and pivot geometry be held to extremely tight limits. Any imbalance that would be masked by an upper jewel in a conventional tourbillon is fully exposed in a flying configuration.

The overcoil hairspring compounds the difficulty. An overcoil’s terminal curve must be formed and adjusted so that the spring breathes concentrically, and in a cage this size the adjustment window is narrow. The terraced cage architecture is a direct engineering response to that geometry: rather than compressing the overcoil into a flat plane, the cage steps up to give the terminal curve the vertical clearance it needs without increasing the overall movement height unnecessarily.

Dial Architecture and the Power Reserve Indicator

With the movement inverted, the dial side of the FB 2TV.1 reads less like a conventional watch face and more like a functional display of the movement’s principal subsystems. The power reserve indicator uses an oversized cone-and-feeler arrangement; at full wind, the cone approaches the surrounding bridge closely enough that the clearance is visible to the naked eye. The scale and hand for the power reserve indicator are set into a sliver of German silver adjacent to the flying tourbillon — a layout that prioritises mechanical legibility over compositional balance.

This approach connects directly to Ferdinand Berthoud’s own working method. The historical Berthoud treated dial layout as a consequence of mechanism arrangement, not an independent design problem. The FB 2TV.1 inherits that logic, which means the dial will read as crowded or expressive depending on the viewer’s tolerance for functional density. From a manufacturing standpoint, the German silver components visible on the dial side must be finished to the same standard as the movement’s internal bridges — because they are, in effect, the same thing.

Decoration and Assembly Hours

Each FB 2TV.1 receives more than 300 hours of decoration. That figure encompasses the hand-finishing of bridges, cocks, and cage components that are now permanently visible from the front of the watch. Anglage on components that will face the wearer must be executed to a consistency that survives close inspection under magnification, and the transition between polished and brushed surfaces on a terraced cage presents the kind of edge geometry that resists automation.

For brands and movement suppliers evaluating what the FB 2TV.1 represents as a manufacturing benchmark, the relevant question is not whether the inverted layout is novel — it is not — but whether the chain specification, the flying tourbillon cage geometry, and the decoration standard can be sustained across a production series. FB’s track record over the past decade suggests the infrastructure exists. Whether the Mesure du Temps 1787 collection expands that infrastructure further will become clear as subsequent references in the line are announced.