Blancpain Fifty Fathoms: Mil Spec Watches

Blancpain Fifty Fathoms: Mil Spec Watches


The year 1953 saw innovations in the dive watch industry that would resound and set the standards for future generations. This was the year when Blancpain released the Fifty Fathoms dive watch intended for the use of combat divers. To this day, the name Fifty Fathoms is synonymous with prestige in the dive watch industry. “Fifty Fathoms” comes from the unit of marine depth measurement and a fathom is equivalent to 1.829 meters. So, 50 fathoms is equivalent to 91.45 meters, which is the maximum depth that divers could achieve at the time given their equipment.

The 1953 Blancpain Fifty Fathoms

The 1953 Blancpain Fifty Fathoms

Originally intended for French combat divers, Blancpain went on to produce other pieces for different countries and their navy branches for the next few decades. Production of the Fifty Fathoms temporarily stopped in the late 1970s but was revived in 1997 when the series was reintroduced by Blancpain as part of a land, sea, and air trilogy of watches. Since then, Blancpain has released many new editions, such as the “Tribute to Fifty Fathoms” and the new Fifty Fathoms Bathyscape.

New Generation Blancpain Fifty Fathoms Trilogy

New generation of Fifty Fathoms: Fifty Fathoms Trilogy, Tribute to Fifty Fathoms No Rad and Aqualung, Fifty Fathoms Bathyscape


The concept for the Fifty Fathoms was conceived in 1952 due to members of the Free French Forces needing a dive watch for their elite team of combat divers called the “Frogmen”. Initially, after testing several dive watches at the time, officers Captain Robert “Bob” Maloubier and Lieutenant Claude Riffaud, could not find one suitable for the needs of their team. The team was tasked with intelligence gathering, sabotaging seaports and ships, often done at night.  The team needed a watch that was highly water-resistant and still visible underwater even at night. Capt. Maloubier drew up the specifications needed and shopped them around watchmakers, but there were no takers. Most of the watchmaking companies at the time were focused on making aviation watches. Finally, Capt. Maloubier (photo below) and Lt. Riffaud met with Jean-Jacques Fiechter, who was Blancpain’s CEO from 1950 to 1980.

Being a diver himself, Fiechter took to the idea and agreed to develop the timepiece for “Les Nageurs de Combat” or “the combat divers”. Fiechter not only agreed to produce the pieces but did them one better and added to the design features. The resulting product adhered to the specifications set by the French Navy and featured innovations for the dive watch industry.

Aside from being known as a navy dive watch, the Fifty Fathoms also had its share of the spotlight as it was used by Jacques Cousteau during his sea explorations which were documented in the Oscar-winning film “Le monde du silence” or “The Silent World” in 1956. The piece was also utilized in the 1964 Gouffre Berger cave exploration in France. Taking part in these conquests only further cemented the fame of the Fifty Fathoms in the dive watch industry.

Blancpain Fifty Fathoms in The Silent World, 1956

A 50 Fathoms worn by André Laban in the film The Silent World 1956


The innovations found in the initial piece intended for the French Navy seemed to entice the military in several other countries. Blancpain received orders from other militaries, such as the German, Israeli, British, Spanish, and the US Navy. The resulting pieces came to be known as Mil Spec watches as it followed certain military specifications. For this guide, these are the incarnations that we will focus on, namely the 1953 model and the Tornek-Rayville model from the 1960s. The vintage Mil Spec incarnations of the series have developed a cult following and are the most sought after pieces.


One of the most sought after versions of the vintage Mil Spec Fifty Fathoms would be the initial model intended for the French combat divers, born out of the partnership between the French Forces officers, Riffaud and Maloubier, and Fiechter. The 1953 model featured innovations such as the unidirectional rotating bezel (URB), the double “O” ring system, and protection from magnetic fields. It’s most telling characteristics though are seen on its dial which featured the markings “Rotomatic Incabloc”. Due to its history, it one of the most wanted pieces for dive watch collectors. Other versions were also produced for the French Navy during the latter part of the 1950s, but the 1953 version will always have a special place and came to be termed as “the initial” or “the original” Fifty Fathom.

Maloubier wearing an early Fifty Fathoms watch

Bob Maloubier wearing a Blancpain Fifty Fathoms


In the 1960s, the US Navy was looking for a watch for their Navy trained divers who would be part of the “Explosive Ordinance Disposal Units”. There were several companies that competed for the contract but eventually all but one dropped out due to the complex requirements.  Allen Tornek, who was then importing pieces from the Rayville Watch Company and manufacturing watches under the Blancpain name, took over the contract.

There were some challenges that Tornek faced, such as making the piece anti-magnetic to follow the MIL-W-22176A specifications for the US Navy. The contract also required that the jewels used be from a company in Missouri. To overcome these challenges, Tornek decided to buy the jewels from the US but did not use them in the actual piece. He instead bought Swiss jewels to be used in the development of the watch. A special steel and hardened brass was also used to replace parts in the cases and movement to achieve the requirements of the contract.

Tornek Rayville diagram and instructions

Diagram included in MIL-W-22176A requirements and Tornek-Rayville instruction manual

The pieces developed are commonly referred to as “Tornek-Rayville”, “TR-900” or sometimes just as “Tornek”, as these are the markings seen on the dial and on the movement. The initial order delivered to the US Navy was for 780 pieces in 1964 and another in 1965 for 300 pieces giving a total of just over a thousand for this model. Unfortunately, these were the only ones ever produced as no more orders were placed. Due to its rarity and history, the Tornek-Rayville is one of the most collectible pieces today.

President Kennedy with the US Navy

Pres. Kennedy with US Navy personnel wearing Tornek-Rayville watches

The initial/original 1953 model and the Tornek-Rayville are a decade apart, but one can still see the similarities between the two.


TR-900 above, and case back below.

TR-900 case back




One innovation in the initial 1953 Fifty Fathom design is the URB which was still present a decade later in the Tornek-Rayville. The unidirectional rotating bezel is one of the innovations added by Fiechter to the original specifications by Maloubier.  The bezel is intended to help time the dive. For safety reasons, it is designed to rotate only in a single direction, so that any mistakes made or accidental turning of the bezel would result in the diver shortening the dive rather than lengthening it.

It is accepted that the 1953 Fifty Fathoms watch was the first dive watch with a unidirectional rotating bezel, barely beating the Rolex Submariner.

The initial model of the Fifty Fathoms had a black lumed bezel with indices and numerical markers. There were two types of bezels used for this model. The first one has a lozenge for the 12 o’clock mark and is typically partnered with the dial with numerical markers. The second one has a triangle for the 12 o’clock mark instead of a lozenge. Both types of bezels have numerical markers for every fifteen minutes and indices for every five minutes.

Initial model’s bezels with the losange marker and triangle marker

Initial model’s bezels with the losange marker and triangle marker

The TR-900 also has a black lumed bezel with a triangle for the 12 o’clock mark. The bezel also has numerical markers for every fifteen minutes and indices for every five minutes. Only a single variant was released for the Tornek-Rayville watches.

Blancpain Fifty Fathoms Tornek-Rayville TR 900 dial

The Tornek-Rayville TR 900


Most of the dials for the vintage Fifty Fathoms are quite similar in that they all have black faces and lumed hands and indices. However, this is where the similarities end. For the initial 1953 model, there are several variations that can be seen with regard to the style of the hands used and the markings.

The first type of dial has numerical markers for every fifteen minutes or what is termed as the 3/6/9/12 dial.  This type of dial has the markings “Blancpain Fifty Fathoms” on its upper half. Aside from these, if one looks closely, there are also tiny numeric markers every five minutes just underneath the indices on the dial. The dial also has radium lumed triangles beside the numerical fifteen-minute markers.

Radium triangle markers

Radium triangle markers

On the bottom half of the dial, above the 6 o’clock mark, there is also the marking “Rotomatic Incabloc”. There are several variations that surfaced with regard to these markings on the bottom half of the dial. More commonly seen is the version of the dial wherein the markings “Rotomatic Incabloc” are not aligned, with the word “Rotomatic” being wider.

1953 Fifty Fathoms Rotomatic Incabloc numerical dial

1953 Fifty Fathoms Rotomatic Incabloc numerical dial

However, there are also some pieces that surfaced with a different format for the markings “Rotomatic Incabloc”. There are those that surfaced where the words are aligned.

1953 numerical dial with aligned “Rotomatic Incabloc” markings

1953 numerical dial with aligned “Rotomatic Incabloc” markings

There is also a version of the dial wherein the words are not aligned, but this time, it is the word “Incabloc” that’s wider.

Blancpain Fifty Fathoms 1953 RI dial with small Rotomatic font and vintage ad

1953 Rotomatic Incabloc dial with small “Rotomatic” font and vintage ad featuring the same version
Image by reficul_x via

The second type of dial does not have any numerical markers but has big rectangular indices as fifteen-minute markers. It would also have circle markers for every five minutes instead of numbers. This type of dial also has the shape of an arrow for the 12 o’clock mark.

1953 Blancpain Fifty Fathoms with non-numerical dial

Rotomatic Incabloc non-numerical dial

For the Tornek-Rayville, there is only one variation for the dial. There are no numerical markers. An inverted triangle is on the 12 o’clock mark and rectangular indices are used for the 15 minute marks. The markings “Tornek-Rayville US” dominate the upper half of the dial. The lower half of the dial has the humidity indicator for the piece. Most of the pieces today have faded indicators with a pinkish hue. Originally, the indicators had a blue part that would change to pink once moisture seeped into the watch. On the bottom part of the dial, there are also  the markings “Swiss” and “PM 147” indicating the type of material used for the lume.

Blancpain Fifty Fathoms TR 900 dial

TR 900 dial with humidity indicator and “PM 147” markings


Even though there are similarities in their aesthetic features, one of the major differences between the initial Fifty Fathom and the Tornek-Rayville is the lume. In the 1950s, it was commonplace for watchmakers to use radium for the luminescent markers on the dial of the piece. This was the radioactive material used in the initial 1953 model. Radium has a half-life that is measured in centuries. Basically, it would take a long, long while before the glow on its lume would diminish. In the 1960s, the dangers of the use of radium were discovered and it was replaced with tritium. This is another reason why the Tornek-Rayville was different, since it did not follow this change. Instead, the piece uses Promethium 147, which would glow brighter and longer underwater but only has a half-life of about 2.5 years compared to radium which would last for centuries.


Both of the models have three-piece case backs. The three pieces are composed of the screw down ring, the case back itself, and the dust cover. The cases for the two models also both measure 41mm, but this is where the similarities end. The markings on the back of the 1953 models are very different from the TR-900 models.

For the 1953 model, the case back itself has the markings “Waterproof Shock Protected Automatic AntiMagnetic” forming a circle on its outer edge. On the upper half of the inside of the circle, it has the “Blancpain” signature. On the lower half, it features the serial number, the markings “Stainless Steel”, and the words “Swiss made”. Aside from the case back, the piece also has a dust cover. The dust cover has the markings in French “En cas d’ouverture de cette boite faire controler l’étanchéité par un dépositaire BLANCPAIN FIFTY FATHOMS” which in the English version reads “In case of opening the watertightness of this watch must be re-checked by an official Blancpain Fifty Fathoms Dealer”.

Blancpain Fifty Fathoms 1953 case back

1953 model case back and dust cover

There are several markings on the case back of the Tornek-Rayville. On the top edge of the case back are the markings “IF FOUND RETURN TO NEAREST MILITARY FACILITY”. Below these words, there are the markings “Rec License” number and then the word “DANGER”. On the bottom part of the case back are the markings “NON MAGNETIC”. At the bottom edge of the case back are the military specifications reference “MIL-W-22176” and “SERIAL XXXX” to signify the serial number for the piece. In the middle of the case back, the markings “RADIOACTIVE MATERIAL 2mc Pm 147 11/64” form a tiny circle. These indicate the material used for the lume, Promethium 147, and the date of production. In the middle of these markings, a tiny trefoil/ radiation warning symbol is placed. The Tornek-Rayville also comes with a dust cover but does not have any markings.

Blancpain Fifty Fathoms TR 900 case back and dust cover

The case back of a Tornek-Rayville with dust cover


Both the straps for the two models were chosen to withstand frequent use underwater. The 1953 models were said to use a black Apollo Tropic strap, which is made of rubber. The Tornek-Rayville, on the other hand, uses a black nylon band. The nylon band may discolor through time and may turn a lighter color due to frequent wear.

Blancpain Fifty Fathoms 1953 and Tornek strap

Apollo Tropic strap used in the early 1950s versions and black nylon band used in the TR 900
Image on left by reficul_x via and watchuseek


The movements used for both of the pieces are by Anton Schild. The one used for the 1953 model was the 1361 whereas the one used for the Tornek-Rayville is the 1361N. The main difference lies with the materials used to satisfy the requirements of the contract with the US Navy.

Movement AS 1361 AS 1361 N
AS 1363 movement
AS 1361N movement for TR 900
Model used 1953 Fifty Fathoms Tornek-Rayville TR 900
Markings Blancpain
Seventeen 17 Jewels
Unadjusted Swiss
No TR-900
No. of functional jewels 17 17
Movement diameter 26mm 26mm
Mainspring dimensions Breadth 1.45mm
Length 265mm
Thickness .10mm
Breadth 1.45mm
Length 265mm
Thickness .10mm
Hacking No Yes
Shock Protection Yes Yes


The escapement for the 1361N is made from hardened brass and has a hacking second. Aside from these, there are no major differences with the two movements.


There are still some pieces of these two models that can be acquired. However, it takes quite a while before one goes up for sale. There are very few of these pieces that still exist with original parts and many collectors seek them. The key is to always be on the lookout and ensure that you have the cash at hand as they come with a hefty price tag.


It is hard to find a piece with all original parts. Due to this, prices for the initial Fifty Fathoms have gone up in recent years. There are some pieces that were sold for around $15,000, but one that was recently put up for sale had a price tag of around $30,000.

Blancpain 1953 Rotomatic Incabloc sold at an auction

Many of the pieces that are for sale have certificates sold with them. These certificates are acquired through sending the piece to Blancpain to be authenticated. However, this is not foolproof as these certificates can be faked. It is best if you can also acquire pictures of the piece and correlate it to the known features of the initial 1953 model. Another way would be to have it checked by a watchmaker or another collector for authenticity. There are several forums dedicated to the Fifty Fathoms and members are usually more than happy to help when it comes to authenticating vintage pieces.


The Tornek-Rayville is definitely hard to come by. Aside from there being only over a thousand ever produced, there were only a few pieces that survived after it was withdrawn from service in the 1970s. Being labelled as containing radioactive material, they were treated as atomic wastes and were sent to be buried in containers deep underground. Most that can be acquired today are from retired military personnel or were pieces passed on as heirlooms.

Tornek Rayville sold at an auction

When looking for a Tornek-Rayville, a good place to start would be auction sites that sell antique or vintage watches. Another avenue that you could try would be watch forums where private collectors sometimes post their vintage timepieces for sale. With its history and rarity, pieces that were sold a few years back cost around $35,000.

It may take a while to acquire these pieces, but patience is the key. A vintage Fifty Fathoms is worth the wait.

From The Spring Bar Store:


  1. Blancpain, History, Website article, n.d.
  2. Brian Dumais, com, Website, n.d.
  3. Christian Dannemann, Technical Instructions / service manuals, Blog post, 2012
  4. David Bredan, The History Of Dive Watches, Blog post, 2014
  5. Eric Wind, Found: An Original Blancpain Fifty Fathoms Box on eBay, Online magazine article, 2011
  6. EverySpec, MIL-W-22176A, Downloadable document, 1961
  7. Hans Friedrich, Watches & Wine – Blancpain/english, Website, n.d.
  8. Hodinkee, A Historical Look At The Blancpain Fifty Fathoms + Live Photos Of Some Early Classics, Online magazine article, 2011
  9. Jeffrey S. Kingston, Blancpain One Man’s Navy, Online magazine article, 2011
  10. Jeffrey S. Kingston, The History and the Legend of the Fifty Fathoms, Magazine article, 2013
  11. Jeffrey S. Kingston, The History of the Fifty Fathoms, Magazine article, 2007
  12. Joe Thompson, The Hunt for the Fifty Fathoms from WatchTime Spotlight: Blancpain – A Test & History Of The Fifty Fathoms, Magazine article, 2013
  13. Meehna Goldsmith, Tornek-Rayville: The Military Dive Watch Bulova was Supposed to Make, Blog post, 2012
  14. Mike Disher, The Birth of the Modern Dive Watch A Conversation with Cpt. Robert Maloubier, Online magazine article, 2011
  15. Montre24 Watch Portal, Religion of Time and watch idols. Cult watch “Fifty Fathoms” – Blancpain (Part 2), Online magazine article, n.d.
  16. MWR user Billy, Reply to Blancpain FF questions thread, Forum post, 2008
  17. MWR user Johnny B, Question about Blancpain 50 fathoms Movements, Forum post, 2007
  18. MWR user reficul_x, Possibly the first gen Blancpain Fifty Fathoms with very rare small ROTOMATIC dial, Forum post, 2013
  19. PuristSPro user amanico, Blancpain collector and PuristSPro moderator , PuristSPro Message Interview, 2014
  20. PuristSPro user amanico, Autopsy of a Cult Watch: The Tornek Rayville., Forum post, 2010
  21. PuristSPro user amanico, Vintage Fifty Fathoms: The difficult quest for information, Forum post, 2010
  22. PuristSPro user amanico, Blancpain Fifty Fathoms 2010 Exhibition., Forum post, 2010
  23. PuristSPro user amanico, The FF Mil Spec, A Quick View and Thoughts , Forum post, 2008
  24. PuristSPro user f, My vintage BP collection. Part 1: Fifty Fathoms, Forum post, 2010
  25. PuristSPro user small-luxury-world, 1953-2013: Blancpain Fifty Fathoms 60th anniversary – Bathyscaphe, Forum post, 2013
  26. Stephen J. Pulvirent, A Week On The Wrist: The Blancpain Fifty Fathoms Bathyscaphe, Online magazine article, 2013
  27. com user billy, A bit of Blancpain history … interview w/ Allen Tornek ! >>, Forum post, 2007
  28. com user James Dowling (MrRolex), The history of the Military Dive Watch, Forum post, 2010
  29. com user Jessica, Blancpain’s Fifty Fathoms Collectors Exhibition, Forum post, 2011
  30. TZ-UK user Andyg, ITS ARRIVED, Forum post, 2011
  31. Vintage Time Collectors author rockster, DIVE WATCHES A HISTORY, Blog post, 2014
  32. Watch World, Diver’s Mate, Online magazine article, 2013
  33. Watch Freeks admin TVDinner, What is a hacking vs non-hacking movement?, Forum post, 2010
  34. Watch Collecting Lifestyle, BASELWORLD: BLANCPAIN. THE ICONIC FIFTY FATHOMS ON DISPLAY, Online magazine article, 2013
  35. watchuseek user Altair, Blancpain Fifty Fathoms Pictorial Review, Forum post, 2010
  36. Watchtime, Watchtime Wednesday: the history of the Blancpain Fifty Fathoms, Online magazine article, 2014
  37. Watchtime, FIFTY-FATHOMS-TO-RICHES, Blog Post, 2013