If you ask any seasoned Rolex or Tudor collector which area of this crazy hobby is the most secretive and shrouded in mystery, they will inevitably reply with the murky world of military watches and in particular Submariners; know as MilSubs. The four most knowledgeable and influential Rolex MilSub collectors in the world are good personal friends of mine and I have literally seen dozens of their watches over the years… and I still am a little baffled by the details. I am, however, very familiar with Tudor MilSubs, which are in many ways a broader subject than their Rolex cousins as they were much more widely issued to a range of military forces around the world.

So where do we start with the Tudor MilSubs? Well, the most important place is the caseback — that’s the key to the Tudors. The British MOD asked Rolex to produce watches that met very detailed specifications and Rolex responded with the military-only versions of Submariner refs. 5513, 5517 and the double reference 5513/17. These watches had to have a specified hand shape (for visibility), 60-minute bezel markers (for accuracy), fixed lug bars (for security) and a circled T on the dial to denote the use of tritium lume on the hands and hour markers.

The casebacks were also fully engraved, but from the front the watches were clearly different to a civilian Rolex Submariner 5513. The military departments that decided to issue their troops Tudor Submariners were a lot less specific in their requirements and were happy to issue their troops standard Tudor Submariners, but they tended to engrave the casebacks to keep track or show ownership of the watches. And so the fun begins…

French connection
Up until a few years ago, the majority of collectors were only really aware of the French Tudor MilSubs — the watches issued by the French National Navy the Marine Nationale (MN) to its divers, vessels and diving school. The most famous of the French MilSubs are the Snowflake Submariners with the “MN” engraving on the caseback — always MN followed by the short form version of the year issued; for example a watch issued in 1976 would be engraved “MN 76”. This format was first used used in 1974, but the story began a long time before that.

The French Navy actually played a key role in the development of the Submariner and was Tudor’s “in the field” research and development partner. It gave detailed feedback on what worked well and what could be improved, which was invaluable to Tudor and shaped not just what was produced for the Navy but also the commercial output of the brand globally.

The first batches of watches delivered to the MN were reference 7922 Submariners. These watches were quite diminutive by modern standards at 37mm and had cases without shoulders either side of the 6mm winding crown – today known as “no crown guard Subs”. Depth rated to 100m they were the birth of the Tudor diving watches and are very collectible today. The immediate feedback from divers was that the winding crown was too small and so a version of the 7922 was created with a new, bigger 8mm winding crown. This new bigger crown made setting the time a lot easier for the divers as back in the 1950s diving gloves were still very thick and cumbersome.

The watches were put through their paces as part of the daily rigour of military service and Tudor was constantly striving to make the watches more robust and able to operate at deeper depths. Reasonably quickly, an updated watch was issued to the MN for testing – the ref. 7924. Visually very similar to the Big Crown version of the 7922, the 7924 was a technological advance due to it being depth rated to 200m. The next challenge revolved around ensuring the watch was as waterproof as possible.

The most obviously vulnerable point of the 7924 was the winding crown and the extra bulk of the 8mm crown was susceptible to getting knocked while underwater, thus causing the watch’s waterproof properties to be compromised. To address this issue Tudor developed the 7928 – the first Tudor Submariner with shoulders either side of the crown, ensuring that the crown was more protected. The 7928 also had a larger and more robust case that helped the watch stand up better to the demands of military life.

The ref. 7928 was produced for almost 10 years, and during this time underwent a number of subtle changes to the case design and dial layout. Again, feedback from field-testing by the Marine Nationale gave invaluable insights into how to best “tweak” the features to make the watch more user friendly. The first run of 7928s featured what we now refer to as “square crown guards”. The French divers, however, gave the feedback that in a similar way to the first small crown 7922, the winding crown was difficult to unscrew and use due to the restricting nature of the crown guards. What followed were pointed crown guards – or PCGs to use collectors’ parlance – which eventually evolved into the final type of crown guards seen on the 7928, rounded crown guards.

Used Tudor Pelagos

Tudor’s blue period
These early (pre-caseback engraving) Marine Nationale watches are becoming a lot more desirable. Whilst the “classic” MN is the blue snowflake on grey NATO strap, discerning collectors are looking to uncover new Tudor MilSubs and find the less obvious pieces with interesting histories. But if they don’t have caseback engravings and so are impossible to differentiate from regular watches, how do we know it’s a MilSub? Well, this is where it can get complicated. But we will come back to that shortly.

In the late-1960s Tudor unveiled a totally new dial and hand layout that became one of the enduring symbols of Tudor dive watches. The often-murky waters in which the navy divers worked made it difficult to make out the positions of the hands. In a bid to make the watch face more legible, Tudor devised what we now know as the “Snowflake” watches, primarily due to the shape of the hour hands. The watches were first formally issued to divers in 1974 and continued to be used officially until 1983.

As mentioned earlier, the watches are easily identified due to the markings on the caseback. The first batch of watches issued in 1974 had black dials and hands. There was, however, an issue with the surface of the dials and many proved to be very susceptible to moisture ingress and developed dial rot. This was obviously a big issue for professional diving watches and so, in the MN 75 watches, a new blue dial was used. These blue dials were much more robust in their composition and stood up well to a life under water. The 1975 watches are actually an interesting watch to highlight. It was this year and this year only that the watches had the full form version of the year engraved on the caseback i.e “MN 1975” as opposed to “MN 75” as per all previous years. Around 1980 Tudor ceased issuing the signature snowflake hands in the watches and reverted to the more Rolex-esque Mercedes pattern hands.

The real deal
So back to the question of authenticating these military timepieces. There are really only two ways to identify a Marine Nationale watch. The first is via a series of service logs known as the Ledger Books. A team of MN approved watchmakers serviced and maintained the watches that were issued by the navy. As a way of keeping a log of the work carried out they kept detailed records in ledger books where the serial number, brand of the watch and which ship or unit the it was issued to were recorded. These books are, therefore, a definitive record of watches that were used by the French Navy in active service. The two most famous ledger books pertain to watches that were issued from Toulon, which are currently owned by a French collector, based in Paris. When endeavouring to authenticate an MN watch, the serial number can be cross-referenced with the ledger books and, if it appears on the records, then it can be safely assumed that the watch is an authentic French MilSub. This is often the only way to check watches without caseback engravings.

The second way that these watches are generally authenticated is the presence of decommissioning auction cards, known to collectors as decom papers. When a watch was retired from active service it were generally decommissioned in two different ways. The unlucky watches were taken by a Stores Master to the harbour, where they were unceremoniously smashed with a hammer and thrown into the sea. The lucky watches were sold at a government auction, where each lot was accompanied by a small card stating its serial number, model reference, NATO stock number and any service history.

Collectors have viewed these papers as almost a certificate of authenticity – the issue being the relative ease with which they can be counterfeited. Over the years it hasn’t been uncommon to witness unscrupulous dealers selling blank fake decom papers at watch fairs. What we do know is that there were certain batches of watches set aside by Tudor for issuing to the French Navy, which are identifiable by the serial numbers on the cases. When buying a watch with decom papers, it is important to ensure that the serial number of the watch falls within an accepted range of numbers.

So the French Navy’s use of these watches was key not only to the importance of the Tudor Submariner as a military watch, but to the actual development of the Submariner throughout the first 30 years of its existence.

In Part II we will look at the other countries that opted to issue the Tudor and why.

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