NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Eitan A
Date: 2017 Sep 21, 10:11 -0700
Thank you Brad,
that is a very informative article. If I understand it right, the term "Hack" watch is a slang or colloquial term for the "comparing watch". In terms of the A-7, which was for use on aircraft, it was to be set against the master timepiece, in this case the aeronautical equivalent of a marine chronometer.
The confusion I have for the term, is that in military watch parlance a hack or hacking watch is normally defined by the function of the mechanism (as outlined in the article), that when the stem is pulled out the second hand stops. The A-7 is a chronograph in which the second hand does not stop when the stem is pulled out, so I was confused as to why it was defined as a "hack" watch. Your article neatly explains this discrepency, as many types of watches can be "hack" watches, the one required function of the watch being that it can be synchronised accurately to the second. Is that your understanding?