Thanks, Konrad!

Martin and Bruce. Thank you both for your excellent additions and hypotheses!

I think the ideas about the dating of the series have good logic, but I am one of those people who want to see copies of records before saying yes. The manufacturer serial numbers for the Omegas are a good start, but without manufacturer serial numbers or RFC/RAF records of some kind for all or most of the other manufacturers I would urge that we consider the proposed timeline as provisional rather than definitive. The war was a hectic time and I am not sure that pure logic will always work in deciphering what happened when.

As for the numbers of these timepieces, I think that the suggested number of 58,000 is more likely to be a reasonable estimate than 9,000. My thinking is based on the number of aircraft the UK built during the war - 58,144 aircraft. If only one watch was purchased for each aircraft and no thought was made for spares and replacements due to wartime losses, that would make the number 58,000 or something on that order of magnitude or likely than a number in the 9,000 range. It could even be a bit higher to provide replacements for expected combat, accident, or other losses.

Hi Jim - have just found this excellent forum and would like to offer an Omega Mk 5, with case, for your list:

On the black dial, BB 929, 30hrs, non luminous, Mk 5.
On the back, WD arrow and A.
Movement No. 5857722, case 5857722.
The watch is in good condition, working, but needing a clean.

Omega Archives say the movement was produced July 18th. 1917 and supplied to the British Royal Flying Corps.

The watch has a bow, was this as supplied or has it been added later? The bow would not have prevented the pilot detatching the watch if clipped to the instrument panel.

Thanks for adding the information on your Mark V, Christopher! The bow on your watch is a later addition. These were not made with bows since they were made to be used as cockpit instruments installed in a holder on the panel and not pocket watches. The bow would have been in the way of a smooth fit into the panel holder, and it would have had no point even if it was able to be forced into the holder with the bow. Typically bows were added in the 1930s and later by either the War Department if the timepiece was still in military stocks and was being recycled as a pocket watch for a soldier, or they were added by private watchmakers if the timepiece had made it out of military hands (legally or illegally) and was being repurposed by a civilian who wanted to save money by having a used pocket watch. The examples of Mark V watches with bows are unfortunately all too common. My guess is that you see something like 3 to 5 examples with added bows to every one that is in its original configuration - that is a very rough and unscientific estimate. The original configuration ones are by no means rare, it is just that they are not quite as common as the ones with this later modification.

A few of these Mark V watches are seen with back markings that include the letters Sth and a serial number. In every case these markings have been added at some point later in the watch's life and I have been researching what they mean. Some people have expressed the hopeful thought that it stands for Sopwith but that does not make much sense since no other aircraft type has ever been seen on these watches. Recently I have seen a couple of references to the Sth being the standard marking for the Southern Railway Company. This makes a lot of sense to me in that the supplemental serial number would make sense for some other organization's owning these. My thought at this point is the Southerrn Railway Company bought a large number of these nice quality watches that were surplussed after the war and repurposed them for their own use by their employees.

Here is a new Mark IV A for the list:

Non-Luminous
H. Williamson Ltd.
London
8 days
Mark IV A No. 4018 AC

Black dial with A and Broad arrow on rear case (obvious case repair along the way)
Movement serial number of 2158639.

Per request of Greg Crockett more photos for this thread.

Close up of rear case markings. I think there was a repair along the way as this case does not have the usual War Dept mark. Is this common Greg?

Another view of rear case

Last one of movement

Hi Michael,

Seems like you have a very scarce and desirable watch. I'm curious, what does the "A" above the broad arrow signify?

John III

Hello John,

I am not the military markings expert but I can tell you that my watch is anything but scarce. There seems to be two or more different RFC watches featured in this posting started by Mr. Greg Crockett in 2004. The Mark IV A and the Mark V cockpit watches and so many members have been donating their time to achieve an impressive collection of numbers and information not really collected this way anywhere before. I can tell you that I think the Mark V watches tend to be in more numbers than the Mark IV A type. Another example of my watch is on page "7" of this same thread posted by Konrad Knirim. Now as for the meaning of the "A" over the broad arrow I feel quite ignorant on the subject as I am sure another member can give more specific information. I believe it means "Aviation" or "Air Corps" or "Air Ministry" of some kind to distinguish that this type watch (Mark IV A or Mark V, just these two in this type thread I believe so far) to belong to that particular division in the armed flying forces of Great Britain. These watch were used in aircraft during the WWI period and went through several changes and variations along the way during war time and after. That is the simplified version as I am sure someone with more experience can ellaborate. I am a new member here (even though I do post a lot..ha ha) and I am sure another member is more knowledgable so please can someone help me out here.....please!

Thank you John for your reply to my postings, I believe this is our first interaction and I see you have an interest in R.R. Grade watches. I am a military watch collector and have only one, a WW2 Hamilton 992b with all the markings. All my best.

Hi John. If you go to the first page of this thread you will see that I started it. I know that it is quite long by now, but there is a great deal of information if you read through it. I started it as a research project to try to develop an understanding of the markings initially on the Mark V, but then it grew to include the Mark IV A models as well. The 'A' stands for 'Aviation' and as Michael mentioned this refers to how the Air Ministry used these - they were cockpit watches in aircraft during the Great war. They were mounted typically in friction holders on the instrument panel of an aircraft, but over time the holders became a little more substantial. This is why the stems do not have bows on them - at least on the ones that have not been converted at a later date to repurpose them as pocket watches.

While 'scarce' is a relative term and you are correct they are not found in the back of every underwear drawer or jewelry box, on the other hand Michael is spot on when he says they are not at all hard to find. Also he is correct that the Mark V is more common than the Mark IV A but neither is a challenge to find and a collection can be started with only a few minutes searching on Ebay where you will normally find one or two for sale almost every week, or if you rummage about in dealers and watchmakers inventories. The prices they attain are all over the place and some sellers think they have the crown jewels if you look at their starting or reserve prices, but if you are patient and let those go by they can be had for a fairly modest prices compared to ordinary pocket watches and even more so compared to rare or the most popular military timepieces such as chronometers. The reason is the Air Ministry bought a very large number of them - something over 50,000 or as many as 60,000 is my guess at this point, and then they kept repairing them instead of throwing them away. Many were even still in use by the second world war and some have auxilliary markings from that time. And then they were surplussed off for many years rather than tossed in the rubbish bin.

Hi Michael,

Thanks for the nice reply. I know very little about Mark V watches obviously, so thanks for being patient with my questions. However, I am an avid collector of military watches made by American companies like Hamilton, Elgin, and Waltham. I inherited a nice collection of them and have added some pieces over last five years.

The reason for my question is that I just picked up a military Omega with the exact same A over broadarrow markings on the back. The serial number is in the 4 millions so it is probably WWI vintage.

I was thinking the A meant either Army or Air Corp, but I wasn't sure if there were many fighter planes in WWI. Since I live in Canada which has the C around the broad arrow (on my 3992B ), I also throught the A could stand for Australia.

Lets hear what the real experts have to say.

John III

Jim,

I see we were typing at the same time. Thanks for the clarification about the "A". I tried searching, but an "A" is hard to search for in a query.

I will keep my eye out for these Mark IV and V cockpit watches now that I've gotten a good introduction thanks to you and others.

John III

Hello,

FWIW, my opinions on various recent queries:

Regarding the 'A' arrow mark:

Personally, I think it significant that, in April 1917, the responsibility for the design and supply of material for the Royal Flying Corps was transferred from the War Office (which used the 'WD' mark for watches, although it was obsolescent by WWI) to the Air Board (established in February 1917). I think this explains the appearance of the ‘A’ marking to Mark V case backs. If so, it most likely stands for 'Air' and dates from 1917 onwards.

Regarding the broad arrow:

The procurement of British war supplies has a very convoluted history (and, some would say, an equally convoluted present). RFC/RAF equipment carried the broad arrow mark (associated with the 'WD' mark and then the 'A' mark) until the inter-war period when the A.M. mark (for Air Ministry) was introduced. This lasted until 1943/44 when the A.M. mark was replaced by the broad arrow mark again (although its earliest reappearance on RAF timepieces is dated to 1942 if I remember - on ref 14A/1102 marked instrument watches). Again, this change was precipitated by a change in the procurement and supply arrangements for RAF equipment.

Regarding markings on the Williamson Mk IVA watch:

The Williamson Mk IVA is an interesting watch but anomalous for two reasons: (1) the Williamson movement is unique (generic movements are used for the two other flavours of Mark IVA, regardless of supplier); and (2) the black dialled Williamson Mark IVA is often seen with the A arrow mark to the case back, whereas almost all other Mark IVAs properly have a WD mark. (The black dialled 'A.G.' marked Mark IVAs are another exception but I personally think these are all redials with new case backs). There is no standard style for the A arrow marking (which seems to vary according to manufacturer) but there was a specified size so maybe the black dialled Williamson Mark IVA was the last Mark IVA watch issued, just after the Air Board took over supply duties and immediately before the Mark Vs were issued and the specified sizes took effect?

By the way, the Williamson Mark IVAs all have cases with serial numbers in a limited range - if you can publish the case number that might confirm whether you have a Williamson case or not.

Hope this is interesting and/or useful.

Regards,

Martin

Thank you Jim and Martin for the further explanation on the “A” and case markings to John III, myself and all others. I knew I was in the general ballpark but it’s always nice to be confirmed. Sorry for the mistype that Mr. Greg Crockett started this topic. I tend to get names mixed up in my head, espeacialy when there are not faces to go with them! Jim, Greg and you Martin are tremendous assets to this forum.

In regards to my watch that I just posted: It is away being serviced but I do know that both the inner dust cover and rear case back have matching serial numbers and will post those numbers when it is returned to me. It will be interesting to see what results we get from those numbers. I am curious to see if my rear case happends to be a repair or replacement. I do notice that when I hold and look at the watch from the side angle the front bezel that holds the crystal does not have the same shape and form for the rear, the rear is more flat. Was that something partular to the design needed for the harness as this was not the case with my Mark V?

Martin, what is the serial number range for the H. Williamson Mk IV A cases? I will cross reference the numbers if I can get the case serial number information early from my watchmaker. Is there a movement serial number range as well?

John III, I will contact you via private email as I have several American made military timepieces as well. I would love know about your collection further but this particular topic is reserved for the Marks. Speak with you soon. M.

Michael,

Apologies for the delay in replying - I was waiting for a black dialled Williamson Mark IVA to be delivered (and it still hasn't arrived) because I have no reliable case information for these (but the distinctive 'A' marking is probably signature enough?)

I have observed the following serial ranges for Williamson Mark IVA watches:

White dialled Mark IVAs (observed issue nos 641AC-2486AC):
movement numbers: 2043673-2113192
case serials (case marked 'W^D'): 2028052-2042416

Black dialled Mark IVAs (observed issue nos 3160AC-4188AC):
movement numbers: 2140301-2165310
case serials (case marked 'A'): [presumably 2xxxxxx]

Out of interest, the movement numbers carried on the other gilt-finished movement that was used for Mark IVA watches show an interesting grouping:

13x xxx: Davenport & Co (‘C’ monograph; white dial only)

142 xxx-143 xxx: Etienne & Cie (‘A’ monograph; white dial only)

144 xxx-145 xxx: Smiths & Son Ltd (‘F’ monograph; perhaps black dials only)

147 xxx: W Ehrhardt (‘AF’ digraph; black dial only)

Regards,

Martin

Thank you Martin,

I am also awaiting mine from repair and have not yet obtained the case number. For what you can tell from the photos, are our watches similar? Would you happen to know the thickness of yours? I ask this as my rear case does not appear to have the same symmetry as the front bezel from a side view. It is more flat. I am wondering if this a common trait in these watches. Thank you Martin, speak with you soon.

Martin and all interested others,

Case serial number for the black dialed H. Williamson Mark IV A is 2074393. Both inner dust cover and rear lid have this same number. Hopefully we can see enough examples to gather more numbers for this database.

Michael,

My black dialled Williamson Mark IVA was waiting for me when I returned from a recent break (which also explains the further delay). The details of my Williamson are:

Issue number: No 3876 A.C.
Movement number: 2157951
Case number: 2072241/6

These data added to yours imply a satisfying progression in the case and movement serial numbers, in line with the issue number. It would be interesting to see if other examples confirm this apparent pattern.

Now I have a black dialled Williamson Mark IVA to hand, another interesting fact emerges: the dimensions of the ‘A’ arrow are indeed small in comparison with the Mark Vs but the Williamson mark matches exactly the specifications reproduced in Konrad Knirim’s book (p 395), which appear to be dated 1917 (possibly October 1917). A quick comparison with an Omega Mark V case back shows an overall dimension for the mark of about 17/32 of an inch rather than the Williamson’s 9/32. This adds fuel to my theory that the black dialled Williamson is a missing link which appeared c. 1917 as the last of the Mark IVAs and before the Mark Vs were issued (which I have previously surmised actually date only from the final 12 months of WWI and are as much a watch of the interwar period as they are of WWI). Presumably, the Mark V markings conform to a later (possibly c. 1918) spec.

Regarding the bezel: I have found that very few Mark IVA cases seem to have interchangeable parts so if the fit is tight that is a good start. The odd thing about the bezels of the Williamsons I have seen is that they have Roman numerals scratched to the edge which you would expect to match the case serial but I have seen none which match so I don’t know what these scratched numbers signify in the Williamson case (unless they are all mismatched, which seems unlikely). The hinged case back does indeed feel a bit flatter on the black dialled Williamson than other examples but the bezel doesn’t look particularly odd to me. I can photograph my examples in profile for comparison if that would be helpful.

Hope this is helpful.

regards,

Martin

Hello Martin,
My example is still out being serviced. My watchmaker was kind enough to get the serial numbers for me. When it is returned to me I will photograph a side view and post the image. Thank you for your reply and information. Hopefully we can see more examples for comparison.

Martin and all interested others:
The Mark IV A was returned to me from my watchmaker and I did take a photo of my watch with a side view to compare with yours. I also took a close up of the rear hinge as well for compare. I hope this helps. Mike