The LM Sequential EVO, released in 2022, was MB&Fs’ first chronograph and 20th calibre; it featured significant technical innovations and an unprecedented combination of timing modes thanks to its “Twinverter” binary switch: independent timing, split-second, cumulative and lap-timer modes. It won the GPHG ‘Aiguille d’Or’, the most coveted prize in watchmaking.
The new Flyback edition goes further than the previous EVO editions: on top of the previous timing modes typically associated with motor racing, it adds the flyback function originally conceived for pilots, bringing the Sequential into the world of aviation.
The new Flyback edition with sky blue dial plate comes in the more classic Legacy Machine styling, in a platinum case with screwed lugs and white lacquered dials – including a tilted hours and minutes dial – on a leather strap.
The Sequential and Sequential Flyback movements were conceived and developed by Stephen McDonnell, who previously created for MB&F the award-winning LM Perpetual.
The concept of this ground-breaking mechanism
In 2022, MB&F unveiled its Legacy Machine Sequential EVO, a twin chronograph that opened up a world of timing possibilities. This ground-breaking chronograph redefined the chronograph as we knew it, winning the hearts of collectors and the coveted GPHG ‘Aiguille d’Or’ award the same year.
Conceived by Stephen McDonnell, one of the original MB&F Friends and the mastermind behind the 2015 LM Perpetual, the LM Sequential EVO was one of those timepieces that was so profoundly useful that it made you wonder why no one had thought of it before. Multiple timing modes allowed you to time everything from two athletes at the same time to consecutive lap times around a track, and even two different dishes in the oven, to name a few of its extremely practical applications.
But if the LM Sequential EVO wasn’t mind-blowing enough, there was another feature that Stephen and MB&F were keen to include: the flyback function. Stephen’s original prototype movement was actually designed with a flyback system on the left-hand chronograph and provisions for it were built into the LM Sequential EVO. But it was extremely complicated to perfect with the watch taking nine months of prototyping, four of which were dedicated to the flyback function alone. Add to this six different re-designs, and all the work and components that went with them, and McDonnell felt that it would be unwise – reckless even – to release the watch with a flyback when there were so many unproven elements in play.
But the dream was there, right from the very beginning, and everything was designed to be able to incorporate it at a later date. The chronographs could have been conceived in several different ways, but only one of these configurations would allow the inclusion of a flyback, changing the fundamental way the chronographs were designed.
The internal jewelling of the vertical clutches is the key to the whole Sequential chronograph, and the new flyback system also requires jewelling, without which it would not work. The system is very subtle, and a great deal of work went into reducing all the friction to a minimum so that the flyback did not cause the return-to-zero to block. To achieve this, McDonnell incorporated a special jewelled roller into the flyback mechanism. Such a component is unavailable directly from any supplier of jewels, so for the first prototype, McDonnell made the jewel himself in order to prove the concept of this ground-breaking mechanism (one of five patented elements).
Two years of secret-keeping and testing were required so that the system would be robust enough in the long term, and now the LM Sequential Flyback Platinum is ready, steady, go!
So, what can it do?
The LM Sequential Flyback Platinum features the same layout as the LM Sequential EVO with two chronograph displays. One has its seconds display at 9 o’clock and minutes display at 11 o’clock. The other has its seconds display at 3 o’clock and minutes display at 1 o’clock. Each of these chronographs can be started, stopped, and reset completely independently of the other, using the start/stop and reset pushers on their respective sides of the case. With the new flyback function, the reset pushers also trigger the flyback if the corresponding chronograph is running. These pushers make up the four chronograph pushers you would usually associate with having two chronograph mechanisms in one watch.
However, there is a fifth pusher, called the Twinverter, located at the 9 o’clock position. This “magic button” as Stephen likes to call it, is the secret that elevates the functionality of the LM Sequential timepieces beyond any existing chronograph wristwatch. It controls both chronograph systems, operating as a binary switch that inverts the current start/stop status of each chronograph. This means that if both chronographs are stopped, pressing the Twinverter causes both of them to start simultaneously. If they are both running, the Twinverter makes them stop. And, if one is running and the other is stopped, the Twinverter stops the one that is running and starts the one that is stopped.
Powering such an engine
The design of the LM Sequential is completely unique. It encompasses two independent chronographs within a single movement, both of which are linked to a common escapement and oscillator. The energy losses associated with a conventional chronograph are well known, so imagine what can happen with two chronographs in a single movement? The losses would be doubled, resulting in unacceptably poor performance. All this functionality within a single watch required the invention of a fundamentally new type of chronograph system, one which would not be susceptible to any sort of energy losses. This is exactly what the LM Sequential does, thanks to the use of its innovative internally-jewelled vertical clutches and their associated control system. The new flyback mechanisms also incorporate jewelled rollers. Thanks to these patented solutions, the Sequential calibre outperforms conventional chronographs in terms of energy efficiency and precision.
Legacy Machine Sequential Flyback launches in a platinum edition with sky blue dial plate limited to 33 pieces.