Guys, Wound For Life has yet another cool history lesson on watches, and this time it's about the A-8
Ground Speed Stop Watch. The watches were manufactured during wartime under the Army Air Corps
Specification 94-27749 by Elgin, and Waltham. Later on post-war, Aristo, Leonidas, and Federal Television
Corp made more watches under the specification MIL-W-6510. All in all the watches were built for about a
decade starting in 1940.
The A-8 was used by navigators in making all kinds of different calculations while in the air. From time, to
speed, using everything from landmarks, and shadows, to averaging sextant readings. Inside the watch
was a 9 or 15 jewel hand wound movement, as well as tiny balance that ticked loudly giving the watch a
cool nickname, the 'jitterbug'. It was also fast, beating a 144,000 bph.
Here is the article with more everyone...http://www.woundforlife.com/2015/03/02/lessons-in-wristory-a-8-ground-speed-stopwatch-2/
A picture of the A-8...