Fifty Fathoms – the first diver’s watch
The story begins in 1952, when the French Ministry of Defence created a special combat unit known as ’The French Frogmen’ under the supervision of Captain Maloubier as Lieutenant Riffaud. The officers set out to commission a watch for their special unit with the requirements to be actually dive and combat proof, with clear luminescent markers as well as a rotating bezel.
As diving computers weren’t a thing of the 50’s so knowledge of accurate time under water served a critical function in calculating decompression, the lockable bezel to show elapsed time was created. Visibility and legibility are key factors when submerged – so enter black dial and luminescent hands and indexes.
The ’Fifty Fathoms MIL-SPEC’ watch was born in 1953 under the reign of, avid diver, Jean-Jaques Fiechter (then CEO of Blancpain). The name Fifty Fathoms originates from a British measurement unit of depth and the actual depth -divers could submerge safely with back-then-available equipment- 50 fathoms ~ 300ft ~ 91m. The watch got its shape in steel and rather large proportions (for the 50’s!) of 42mm diameter coupled with long lugs and a screwed caseback. As the leading innovation behind making the actual water proof watch was the patented double O-ring seal in the crown. Also a automatic movement was chosen from the beginning to avoid unnecessary opening of (winding via) the crown.
The modern Fifty Fathoms (pictured ref. 5015 1130 52A) houses the true to origin automatic caliber 1315, bi-directional winding with triple barrels (120h power reserve) and a free sprung balance – for better shock resistance. Over all a beautiful and highly finished movement in the robustness of a 45mm stainless steel diver’s watch.