For those unfamiliar with the Seiko ‘Pogue’ story, Colonel William Pogue, a NASA astronaut, bought a Seiko 6139-6005 on layaway at the Army and Air Force Exchange of Ellington AFB in September 1972 for $64. He then took that same watch on the Skylab 4 mission from November 16, 1973, to February 8, 1974 inadvertently making history and and turning the Seiko 6139 a space icon.
Now, if you are thinking that all NASA astronauts have Omega Speedmasters in the 1970s, you’d be right but Colonel Pogue did not receive his until after his Skylab training. With no Omega in hand, Colonel Pogue completed his training using the Seiko as his primary timing device. When deciding which watch to take on the mission, the one he had trained with for over 6 months or the official mission watch, he made the pragmatic decision and took both. To honor that fateful decision, November 16th has become known grandly – though totally unofficially – as ‘International Pogue Day’.
Colonel Pogue was not the only member of the crew to sneak his personal watch on board on that mission though. Remarkably, Commander Gerald P. Carr took aboard his own Movado Datachron HS 360 watch, and it too, was an automatic chronograph, containing an El Primero movement jointly developed between Zenith and Movado in 1969.
The Pragmatic Pilot
William Pogue become an astronaut in 1966 and was assigned to the Apollo 7, 11 and 14 missions as a member of the support crew. He was appointed pilot of the fourth and last mission to the Skylab space station in 1973. As pilot, the responsiblity of the engine burns and their timing was his. This level of responsibility perhaps explains why he preferred to trust a watch with which he had performed many simulations reliably back on Earth rather than trust a new watch with which he had no experience once in space.
In his recollections of using the 6139, Colonel Pogue mentions the usefulness of the rotating inner bezel to time thruster burns. Famous, now for taking a Seiko into space, William Pogue was better known at the time of the mission for being the first astronaut to go on strike while in space, demanding less work and more free time in which to contemplate the universe and his place within it!
This entire story only came to light in 2006 when an avid watch enthusiast David Bruno from New Jersey read that Colonel Pogue had used a Seiko Chronograph on the Skylab mission to time thruster burns. If this was true it would mean that the Seiko was the first automatic chronograph in space since Skylab 4 was ten years before the NASA-sanctioned Sinn 142 chronograph flew. The realization that the Movado automatic chronograph also flew on that mission would not happen until 2020, then making the Seiko joint-first.
Mr Bruno wrote to Colonel Pogue to confirm the story, which he did along with providing additional details. For example, the Seiko was not officially sanctioned by NASA, nor did they even know William Pogue was planning to take his personal watch on the mission tucked into his spacesuit pocket. Once onboard Skylab he wore the Speedmaster on his right wrist and the Seiko on his left. He chose to use only the Speedmaster for EVAs (spacewalks) since it was certified for that purpose. He also confirmed that the Seiko’s magic lever winding mechanism worked perfectly in zero-G.
The Seiko performed flawlessly on the mission and Pogue continued to wear the watch until 2003, often in preference to the Rolex he also owned. The watch was auctioned on October 7th, 2008 by Heritage Auctions to raise funds for the Astronaut Scholarship Foundation, hammering for $5975 including buyers premium. Colonel Pogue passed away March 3, 2014, at the age of 84, at his home in Cocoa Beach Florida.
What is a true Pogue?
There has been some dispute over the exact model Colonel Pogue bought from the Air Force exchange in 1972. The exact model number was not recorded on the receipt nor was it confirmed by Colonel Pogue’s testimony. Unfortunately a number of Internet articles, for example, here, here and here claimed that his watch was a 6139-6002 model but this is not correct.
To understand the errror, we need to make a brief excursion into Seiko case codes. Vintage Seiko models of this era can be identified by an eight-digit case code. The eight digits are formed from two groups of four with the following structure:
Where ‘aaaa’ is the caliber code, also known as the movement code, ‘bbb’ is the case design code and ‘c’ is either a regional sales code and/or a case design version number.
The seven digit ‘aaaa-bbb’ sequence uniquely identifies the watch model, so in our case, Colonel Pogue’s model is a 6139-600X since 6139 is the caliber code, the case design code is 600 and Seiko used an X in the eighth position to mean ‘all regions and versions’.
The regional codes Seiko used were:
0 - Japan/domestic 1 - Japan/domestic (usually a case design revision e.g. monocoque to screwback case) 2 - Rest of the world, sometimes abbreviated to RoW 5 - US/North America 9 - US/North America
Since the the watch was bought in the US, it would have been either a 6139-6005 or 6139-6009 as those were the model codes for the North American market. The 6139-6002 model code was strictly for the rest of the world. There is no case back photo of Pogue’s watch to prove this but we don’t need one. The dials were also different for the different regions. Only the 6005 had the word ‘AUTOMATIC’ below the Seiko logo on the dial. All of the 6002 variants have the words ‘AUTOMATIC CHRONOGRAPH’ below the Seiko logo. This difference is also apparent in the dial codes: 6139-6009 for the USA model and 6139-6030 for the RoW model. Colonel Pogue’s watch only has ‘AUTOMATIC’ text under the Seiko logo.
So clearly the claim that the Pogue’s model was 6139-6002 is wrong, but was Pogue’s watch a 6139-6005 or a 6139-6009? The -6009 model was only used in in 1969 into 1970, with the 6005 model used from 1970 through to the end of the range in 1978. So to answer that, we need to work out the manufacturing date of Pogue’s watch. This is possible using the water rating text printed on the dial. Seiko used the following ratings:
1. Water 70m Proof from 1969 to mid-1970 2. Water 70m Resist from mid-1970 - late 1972 3. No markings from late 1972 onwards
Colonel Pogue’s watch had ‘Water 70m Resist’ printed on the dial which confirms the watch was manufactured in 1970, 1971 or 1972 means it must have been a 6139-6005. If you have heard the term ‘True Pogue’ tossed around, it is this model that term refers to: a yellow-dialed 6139-6005 with ‘Water 70m Resist’ printed on the dial.
The movement at the heart of Colonel Pogue’s chronograph is the Suwa Seiko 6139. The world’s first automatic chronograph (regardless of what Zenith and Movado claimed with the El Primero). 6139 production started in October 1968, with Japan sales starting in May 1969 with exports starting in August 1969. Zenith presented the El Primero in January 1969, three months after 6139 production started in Japan.
The 6139 was a developed from the existing caliber 61 being used in the Seiko 5 sports range and a number of diver watches, such as the 6106-8110 ‘Captain Willard’ diver. Caliber 61 went on to spawn the 61GS series of Grand Seiko watches and even the 6117 world timers. The main engineer on the 6139 project was Toshihiko Ohki who was also the engineer behind the 1964 Olympic Games chronographs and had developed the base 61 movement, so he was well-placed to to develop a more advanced chronograph, based, unsurprisingly on his own 61.
The 6139 featured the world’s first vertical clutch in a chronograph. Up until the 6139, all chronographs had horizontal clutches with their known disadvantages when engaging and disengaging. Basing the new chronograph on caliber 61 with its integrated automatic winding mechanism necessitated a different approach for the chronograph complication. With no space to swing a horizontal clutch, Toshihiko Ohki had to design a clutch that engages and disengages the fourth wheel from the center seconds pinion. The clutch uses a unique type of spring that is very stiff horizontally to grip the fourth wheel without slipping but soft enough vertically to be moved by the chronograph levers to disengage from the fourth wheel when needed.
All manufacturers that feature a vertical clutch today for instant chronograph engagement have taken inspiration from the 6139’s ground-breaking mechanism. These achievements were all the more impressive when, according to Toshihiko Ohki, everyone except himself and one other member of the engineering department at Suwa were working on the upcoming Quartz Astron movement that would debut on Christmas Day 1969.
As well as having the first vertical clutch, the 6139 has quick set for both day and date wheels – quite the feat for an already complicated movement. The only feature missing was manual winding which often was not a priority at Seiko since they had such faith and pride in their magic lever automatic winding system. Manual winding was later added to the related and more complex 6138 movement, released in 1970.
Two versions of the 6139 movement can be found in the 6139-600X. Watches manufactured up until mid-1971 used the 6139A with Ohki’s original design of chronograph wheel incorporating the vertical clutch. This design was revised in 1971 to form the 6139B which also featured different bridges and levers and so many of the chronograph parts are not compatible between the A and B movements.
Seventeen- and 21-jewel variants of both A and B were produced with the 21-jewel movements only available in the 6139-6000 Japanese versions. The rest of the world got the more basic 17-jewel version with steel bearings in three places instead of jewels and no lower cap jewel on the escape wheel.
Overall the movements are reliable and robust. The clutches in the chronograph wheels do eventually fail at which point the chronograph wheel will start slipping compared to the fourth wheel and the central seconds will start taking longer than 60 seconds to rotate. New, old stock chronograph wheels are still available but are getting hard to find. A number of watchmakers have been able to rebuild and fix bad wheels, but it is not an easy task.
Characteristics and Variations
By now it is probably apparent that there are many variants of the 6139-600X which we will describe in the following sections.
The Case, Crown and Pushers
All models have the same tonneau-shaped case with polished sides and circular brushing on top. Edges should be sharp but given the age of these watches, many have been polished. For the first year of production cases were ‘notched’ at the crown, so every ‘proof’ dial should be in a case with a notch. Early ‘resist’ dials might also come in notched cases, but in that case the serial number should indicate 1970 production.
The pushers and crown were consistent throughout production. The pushers are cylindrical with no markings and should always have a 45-degree bevel on top but this can soften with heavy use. The crown is finely knurled and slightly concave with a distinct dimple in the center.
T and R Dials
While Seiko is known for vertical integration, back when the 6139 was being made, Seiko used external companies to produce dials. The letter at the end of the dial code indicates which subcontractor made the dial:
- T dials were made by Hamazawa Kogyo Co Ltd (became part of Seiko Epson in 1986)
- R dials were made by Shokosha Co Ltd (still independent)
Many Seiko models were produced uniquely with either T or R dials but for the 6139-600X we see examples of both, and they are slightly different when examined closely.
Most early watches have T dials with none appearing after about 1975. Most later watches have R dials which started appearing in 1972 and became the only dial used in the last three years of production until 1978. Therefore, all ‘Proof’ dials and most ‘Resist’ dials you see are T dials, while the dials without a water rating are split pretty evenly between the two types. There does not seem to be a geographical split between the two dial types; all regions seem to have received both types.
The two types of dials are a typically seen with different shades of yellow. The T dial tends to fade from their original darker yellow to a distinctly lighter and more translucent shade. The R dials tend to keep their original shade with age. I suspect the layer of yellow dye is thinner on the T dials than the R dials; a theory supported by how the T dials tend to age. Most T dials have corrosion around the edge of the minute totalizer sub-dial caused by the very thin lacquer in that area.
All dials bear the Suwa logo just above the top of the minutes sub-dial indicating that the 6139-600X was a product of the Suwa Seikosha factory in Nagano, rather than the Daini Seikosha factory in Tokyo. North American models (that is all -6009 and -6005 models) also have the jewel count printed just above the logo. Seventeen-jewel models produced for other markets do not have the jewel count mentioned.
Which dial looks better is pure a matter of personal taste. If you prefer the faded yellow of the Colonel Pogue’s own watch, then look for a patinated T dial, if you prefer a richer, deeper yellow, then look for an R dial.
And then there are the reverse-lume dials. The regular 6139-600X dials have a very distinct marker with two levels, a lower level closer to the center where the lume sits, and a higher polished ‘step’ with no lume. The overwhelming majority of dials have these markers, but there are some dials that have their lume applied the wrong way around with it on the smaller outer step and none on the lower level. While very rare, there seem to be too many occurrences of these dials for them to be accidental or due to incorrect restorations.
Lume on all dial types starts white and then ages to a pale grey with slight puffiness in dry conditions. The lume gives off a pale green glow and while original lume still glows after 50+ years, it doesn’t last long. In the presence of moisture, black spots can appear along with a general darkening of the grey. In the presence of significant moisture, the lume can turn an unpleasant black.
The 6139 chronographs were branded Speed-Timers in Japan and have different dial designs compared to the rest of the world. These dials have the red Speed-Timer logo below the Seiko logo where we would normally expect either ‘AUTOMATIC’ or ‘AUTOMATIC CHRONOGRAPH’ text. On the left-hand side the Seiko 5 logo and blue ‘SPORTS’ label are printed above the water depth rating of 70m. Yellow-dialed Speed-Timers are relatively rare, with production stopping after around 6 months apparently due to the unpopularity of this dial compared to the blue version in Japan.
All Seiko 6139-600X models feature a fixed tachymeter outer bezel. The tachymeter scale can be used to calculate the speed of something over a fixed distance of 1 mile or 1 km The tachymeter scale starts with blue section at 250 which is the fastest time that can be calculated. The tachymeter continues around the blue section until it gets to 12 o’clock (where 1 mile in 1 minute = 60 mph / 1 km in 1 minute = 60 kmh) at which point the tachymeter continues in the red section, measuring down to 50 mph/kph.
The outer bezels of early watches use a lighter blue than the later versions. Compare Colonel Pogue’s 1972 watch compared to the photos of my later 1976 and 1974 models. Up until mid-1976 there is no white block at the 60 mark. After mid-1976, a white block appears at the 60 mark.
The ring that forms the inner bezel sits loosely between the crystal and the case. On its underside are small teeth that mesh with a small gear on the stem so that the bezel rotates when the crown is turned. All inner bezels start out the same shade but the yellow fades to white in the presence of UV. Colonel Pogue’s example faded to an off-white over the years that he wore the watch. The black markings are printed on and with time, the ink can separate from the underlying plastic. The 12 o’clock lume triangle is really a quadrilateral with a flattened tip. It has a thin, printed black border.
The standard hands have a tapered stick shape, with a ridge in the middle and a lume plot running approximately half of the length of the hand. The hand lume ages in exactly the same way, and at the same rate as the dial lume, so one expects the hand and dial lume to match when everything is original. French and UK markets got completely different black hands painted white for some production years. The same hands are more normally seen on 6138 models.
The central seconds chronograph sweep hand came in two designs. Early watches, 1969 through to late 1970 examples came with a two-part hand, with a central steel collet and a separate red sweep section. These are actually superior in design and allow the resting position of the sweep hand to be adjusted on the keyed center-wheel pinion. The one-piece hand has redesigned sweep section permanently joined to the collet. Seiko routinely replaced the two-part hand with the later one-piece hand during service so the two part hands are now rarely seen. These hands are supposed to be replaced every service, but since the supply of original hands has long since dried up, nowadays watchmakers will try to re-use the existing hand, tightening as necessary.
The minute totalizer hand has a distinct tear-drop shop with a visible steel collet in the center. It’s color should match the red seconds hand. If either has a more orange-colored hand, it has been fitted with a hand from the blue-dialed 6139-600X, a model you can read about here. Note that in Colonel Pogue’s own watch, the minute totalizer hand had been replaced at service with a generic black hand of the wrong shape.
All 6139-600X watches came on stainless steel bracelets. The designs varied by region. The most common bracelet outside of Japan was an H-link bracelet but a jubilee-style bracelet was also used. Up until 1975, the H-link bracelet was straight where it meets the case but after 1975, the bracelet is wider where it meets the case and transitions smoothly to the main part of the bracelet. The lug width is 18mm.
Thong-Sa were the Hong Kong-based importer of Seiko watches for SE Asia and Australia in the 1970s. The 6139-6002 models that Thong-Sa imported were sold with black rather than yellow inner bezels. It’s not clear why these watches had black inner bezels but there are sales brochures from Seiko and Thong-Sa showing the watches officially in this configuration. Since Thong-Sa also owned the Stelux bracelet manufacturer, all Aussie Pogues came on Stelux rather than Seiko bracelets.