Blancpain Fifty Fathoms Aqualung

This, I could fairly argue, is perhaps one of the most attractive vintage dive watches to ever exist. The Navies of France, Germany, and the United States all used the now-legendary Fifty Fathoms at some point in time and in so doing made it a relatively famous and desirable tool. Blancpain produced about twenty versions of the Fifty Fathoms between introduction and the 70s. Of these, those sold under the Aqualung name, a diving equipment shop, name went to civilians. The most famed of these are probably the ‘No Rad‘, with a giant radiactive symbol and X at 6 to indicate tritium. However, before that, Fifty Fathoms were still sold with the Aqualung name in the era of radium. This example hails from that early civilian radium run, and it’s rather well-preserved.


The first Fifty Fathoms were truly the first ‘modern’ dive watches. By modern, I mean a uni-directional rotating bezel with substantial water resistance. Captain Robert Maloubier and Lieutenant Claude Riffaud of the French Combat Diving School required a watch for their most elite divers to measure elapsed time at depth. The market didn’t seem very wide to most of the Swiss watchmaking houses. Only Jean-Jacques Fiechter of Blancpain, a diver himself, saw the practical commercial appeal of a water-resistant watch. Fiechter managed to design a dive watch with Fifty Fathoms, or ~90m, of depth rating. As you may be aware, the formula caught on. The watch they created together was a massive 41mm to accommodate is rotating bezel, a first. The luminuous dial had to be visible with an easily-distinguished 12 marker. Water resistance was accomplished through a screw down case back and reliability of timing was ensured through an automatic caliber. The crown would not have to be adjusted or wound to keep time. This was crucial, because Blancpain could not include a screw-down crown. The technology existed, but Rolex held its patent. The result was a free crown with gaskets, not to be adjusted whilst diving. The model proved wildly popular, particularly after Jacques Cousteau wore his in ‘Silent World’.

The Fifty Fathoms was de rigueur amongst a certain set of hardcore divers, and it was only a matter of time until the public got involved. Aqualung was first the name of a diving regulator invented by Cousteau and engineer Émile Gagnan, which later evolved to also be the name of their retail presence. The Fifty Fathoms had already impressed one of that pair, and the path to retail went through Aqualung.


The case on this example is lovely, ultra-sharp. The dial shows a slight bit of spotting and the lightest bit of radium burn. These are almost unnoticeable unless inspecting closely, and stand today as proud signs of it having not been refinished. The bakelite bezel has the smallest crack in its triangle but is otherwise perfect. It comes from a well-regarded Miami retailer.

Find this Fifty Fathoms here from Menta Watches for 32800 USD.

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