TM 9-1575 Ordnance Maintenance: Wrist Watches 12-2-2024
https://archive.org/details/TM9-1575
https://ia801604.us.archive.org/3/items/TM9-1575/TM9-1575.pdf
https://wornandwound.com/military-watches-world-11-watch-won-war/
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England, 1945. A nighttime briefing of U.S. Army Air Forces personnel is in session, prepping the flight officers and enlisted men with details on target, weather conditions, aircraft, payload, and more. Just one thing remains.
“Gentlemen,” begins the briefing officer, “the time on my command will be exactly 21:00 hours.” The men wait for the seconds hands on their government-issued A-11 watches to line up exactly with 12, and then pull out the crowns and set the time to 21:00. They wait for the command to proceed.
“Hack!” says the briefing officer. The men simultaneously push in the crowns on their watches, all perfectly synchronized, to the second, to 21:00.
“Good luck!” he continues. “Now go bomb Berlin.”
Though numerous wristwatches were produced in the U.S. and issued to the military during World War II, the A-11 is perhaps the most iconic.
With its legible black dial, white indices, nickel or silver case and one-piece strap, the A-11 has become synonymous with American horological prowess and industry, with tens of thousands made during the war for Allied soldiers.
Early on during the conflict it was recognized that a modern military wristwatch that could stand up to the rigors of combat would be needed for issue to Allied personnel, which led to the development of the A-11 spec (the watch itself is generally also referred to as the A-11, though this is technically the name of the production standard.
The A-11 specification calls for the use of a minimum 15-jewel hacking movement, making the production guidelines more specific and stringent than those for the “Ordnance” watches outlined in the TM 9-1575 War Department Technical Manual for Wrist Watches, Pocket Watches, Stop Watches, And Clocks (these watches were produced for non-aviation personnel and can be found with many movement and dial variations produced by several American manufacturers).
Because the spec also called for a center-seconds movement, most manufacturers seem to have begun with a 15-jewel sub-second movement (such as those featured in many of the “Ordnance” watches) and simply added a second hand pinion and extra jewel, bringing the total jewel count on these movements up to 16.
All watches were also required to feature hacking (second hand stops completely upon pulling out the crown) for ease of synchronization and precise timing, and movements tended to be of high grade and quality, such as the Elgin 539 and the Bulova caliber 10AK CSH (the latter issued by the British as the Mark VIII).
All in all this made for a simple, accurate, high-grade wristwatch that could stand up to the rigors of use in the field and be easily maintained and serviced. Though a 32mm case is tiny by today’s standards for a men’s watch, in the mid-1940s the A-11 was meant for use as a navigation timepiece, and many thousands indeed saw service as such during the war by USAAF crews.
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This is the watch my dad reparied in WWII.
Its a great watch.