1943 WW2 Hamilton 4992B open-faced U. Military Issue (Air Force) Navigational Hack pocket watch.
16-size watch - measures approximately 52mm (2) diameter. Case - Chrome plated brass screw-back and bezel case. Usual scratches and wear found on a military case along with patches of brass showing through along the edge where the carrying case arms have rubbed. Case back is engraved with An 5740, MFRS PART NO 33106, SERIAL AF 43- 23030 CONTRACT NO. W535 ac-40783, Hamilton Watch Co.
Dial - Black 24-hour dial, full set of hands, marked GCT. Crystal - Appears to be plastic/acrylic and discolored/scratched from use. Movement - nickel ¾ plate movement has a lever escapement with a micrometer regulator, a raised centre seconds wheel on the top plate and capped jewel settings.
The movement features a hacking function when you pull out the winder to set the hands, the balance will stop enabling you to synchronize with other timepieces. The movement is signed Hamilton Watch Co, 22 Jewels, 4992B, Adj. & 6 Positions # 4079308. Stem wind / stem set. Carrying Case - comes in a heavy two part steel case with an inner section for the watch suspended by 4 springs.
The watch is mounted on a felt lined platform attached to the springs to absorb the vibration of the aircraft. The lid of the case has a revolving cover and glass.
The cover has 2 locking slots and clasp. The case has an affixed plaque Case, Carrying Watch Navigation UA Army AC, Geo. Adamson, Tecumseh, Michigan, USA The case is in original unrestored condition.It has some paint loss and a crack above one notch but still holds firmly in place. The 4992B from Hamilton was a modification of the standard and highly accurate 992B that was being used for the rail systems of the time. The movement had been modified to run a 24hr dial and added a larger centralized second hand, rather than the smaller sub dial that accompanied most pocket watches. The next added feature that would set this watch apart from other pocket watches, and watches of the day, is the hacking feature. Hacking in a watch is when the second hand is paused when the balance is touched by a small spring inside the movement. This allowed the servicemen using the watch for their missions during WW2 to all synchronize their watches to a central command time to plan their attacks, especially for the U. That were using these watches to time their bombing runs, and ensure their proper geographic positioning.
The GCT on the dial is in reference to Greenwich Civil Time, with which all Allied actions were based. Beautiful pocket watch with fascinating history - a treasure. The item "1943 HAMILTON WW2 US ARMY Air Force Military 4992B Pocket Watch 22 Jewels + Case" is in sale since Tuesday, December 1, 2020. This item is in the category "Jewelry & Watches\Watches, Parts & Accessories\Watches\Pocket Watches".
The seller is "rugsaddict" and is located in Oakland, California. This item can be shipped to United States.