IWC Mk 11 (1952)
This is a rare and desirable International Watch Company Mark 11 navigator’s wrist watch, to quote the original Ministry of Defence specification, “The wrist watch mark 11 is a highly accurate time piece suitable for astro-navigation purposes”. This watch was used by the navigator in an RAF plane in conjunction with a bubble-sextant to calculate the exact latitude and longitude of the aircraft. This method was in principal the same as that used by sailors to calculate their position ever since the development of the marine chronometer by John Harrison in the mid eighteenth century.
The Mark 11 is probably the most iconic British Military watch there is, it was produced in relatively small numbers and only ever supplied by two firms: International Watch Company and Jaeger Le-Coultre. The watch was designed to withstand the harsh environment of a military airplane - it was constructed in such a way as to shield the mechanism from the strong magnetic fields which were present: the dial is made of iron and considerably thicker than that found on a regular watch, an iron dust cover wraps around the back of the movement and joins with the dial to completely enclose the movement and so prevent the influence of magnetism on the time keeping.
The Mk 11 watches were considered such valuable military property that the case and dial and even the movement itself was marked with the military pheon. The watches were subject to an exacting maintenance schedule, indeed initially they were returned to the manufacturer annually for service and for testing to to ensure they conformed to the original time keeping specification. No other military watch was ever subjected to such a rigorous testing and maintenance schedule.
There is an excellent article about the Mark 11 watches which gives fascinating context and insight into them here
This watch is a good, honest example - it shows some sign of it's active service life: The case has some scratches and dings as is to be expected. The seconds hand has lost a little paint and the '6' numeral has been touched up at some point in the watches life. None of these detract from what is a very handsome, wearable watch and a model which has been steadily increasing in value over the past few years. Curiously the crown appears to have a crucifix marked into it, something I've never seen before.
The movement has been fully serviced and the timekeeping is excellent, the watch has a hacking function - that is the seconds are stopped while the time is being set, so it can be set to the exact second. The case has been cleaned, but as with all out vintage watches we have left it unpolished. The crystal has been polished and the watch has been fitted with a nato one-piece strap which complements the watch wonderfully. The watch comes with our standard 12 month guarantee.
One of the things that makes the Mk 11 so special is the combination of exacting, chronometer-grade performance and a pure, minimal design of the visible parts of the watch. To my mind they are the very essence of horological understatement.
Case diameter: 36mm
Case material: stainless steel
Strap width: 18mm
time keeping: grade A+ (on my wrist it runs to within a few seconds per day)