Blancpain : Fifty Fathoms Bathyscaphe Flyback Chronograph

It’s been several years since Blancpain breathed new life into its iconic collection of “Fifty Fathoms” diver’s watches. By reinterpreting the appealing aesthetic of the original references, while equipping them with the latest technologies, the contemporary models have earned themselves a well-respected place within the competitive world of diver’s watches. The Bathyscaphe Flyback Chronograph with a ceramic case was the model entrusted to us for a test bench in deep waters.


Exterior :

There are no surprises when it comes to the design, since the key lines clearly stem from the splendid 1950s original, appearing in a contemporary interpretation that the current collection has already introduced and established as a pleasing aesthetic. Our attention therefore focused on the materials and the way in which they are presented. The brushed black ceramic case is both discreet and elegant, while the ceramic rotating bezel is of course unidirectional and moves with a perfect click in the author’s opinion. That is of course a personal view, but the handling of this bezel is accurate and smooth, yet sufficiently resistant to avoid any accidental rotation. The push-button head is neither screwed nor locked, but Blancpain guarantees their functionality to 300m, a figure that could not be tested within the framework of this set of trials. However, the crown is screw-locked and and its adjustment as well as its pump-spring make it extremely pleasant to use and give it a definite sense of reliability. The dial and hands are directly inspired by the 1950s models. The color of the silky dial makes an elegant match with the polished and brushed black shades of the 43mm-diameter case. One notes the clever use of Superluminova applied to the hours, minutes and seconds functions, as well as the rotating bezel while bypassing the chronograph indications. A clear-cut will to ensure functionality that will satisfy all those who dive with such a watch.


Movement :

The new Blancpain F389 caliber is a self-winding flyback chronograph movement delivering tenth of a second precision, since its regulating organ oscillates at a rate of 36,000 vph. It is particularly the latter feature that earns it the title of ‘new’ caliber, since most of this chronograph comes from a caliber formerly manufactured under the name Frédéric Piguet. The functions are controlled by a column wheel and transmission to the chronograph is handled via a vertical clutch. This mechanism shows no loss of precision due to the angular displacement of the chronograph third wheel or of the oscillating pinion and ensures reduced mechanical latency. The friction of the vertical clutch calls for absolute mastery of the production of its components, and one well remembers that the first versions produced back in the day for many brands underwent a number of modifications in the chronograph wheels, thereby casting certain doubts on their reliability. The tests will show whether the Blancpain technicians have successfully resolved the conundrum faced by their colleagues.


The flyback function has two major advantages here. Firstly, its functionality. Initially designed to facilitate airborne maneuvers and navigation, it proves extremely useful when undertaking successive underwater measurements such as decompression stops. In addition, this function indirectly enhances mechanical security, since it avoids any risk of breaking the chronograph lever by inopportune zero-resetting.


On this occasion, a special escapement and a regulating organ oscillating at a rate of 36,000 vph were developed, The size and the inertia of the balance-wheel are lower, but tests revealed that this was a correctly calculated compromise. The winding of this automatic movement is handled via an 18K gold oscillating weight guaranteeing 50 hours of running autonomy


The finishes are those one would expect from a good-quality series-made sports watch. One might perhaps have appreciated a little more effort in this respect, but the quality-price ratio displayed by this watch fully justifies such an approach.


Tests :

The most appealing part of this new interpretation of the flyback chronograph is that the constructors have made clear-cut choices. By opting for a 5Hz frequency, they have chosen to minimize the size and inertia of the balance-wheel, while nonetheless maintaining a 50-hour power reserve. In this efficient automatic movement, the balance wheel receives a constant supply of maximum energy. The high frequency of the sprung balance amply compensates for the compromise on size and inertia, as well as the narrower than usual amplitudes.


Rate tests were performed with the chronograph in activated mode. The vertical coupling clutch means that less energy is used when the chronograph is in operation. The amplitudes measured between 0 and 24 hours never exceeded 282°, albeit with logically smaller differences between horizontal and vertical positions. The rates all corresponded to good precision-timing results (0-5 seconds/day at 0H ; 0-6 seconds/day at 24H).


The silicon balance-spring also prevents any magnetic disturbances. Finally, we took a special interest in the vertical clutch. The loss of amplitude is minimal when the chronograph is activated and immediately stabilizes thereafter. The operation was performed many times and yielded the same results, thereby confirming that the Blancpain R&D department has successfully mastered the tricky issue of the vertical clutch. The Bathyscaphe Flyback is supremely comfortable to wear and the additional canvas strap further enhances its ergonomics.


Conclusion :

With this Flyback Chronograph, Blancpain undoubtedly brings us one of the finest and most legitimate models in the collection. The choice of its regulating organ is ideally suited to the context and fully mastered. Its tried and tested reliability clearly reveals the praiseworthy efforts undertaken in this respect. The style of this diver’s watch is appealing and perfectly executed. Nonetheless, the very fact that the craze for these models has brought such a plethora of them in recent years might almost lead one to think that this superb Bathyscaphe Flyback Chronograph is excessively modest and discreet. Especially since it is home to a benevolent siren seen with my very own eyes…


Cet horloger chevronné analyse une montre qu'il porte pendant toute une semaine et en livre son bilan technique et esthétique

Review overview