WALTHAM CDIA (Civil Date Indicator Aernautical)
At the beginning of the Second World War, the clock provisions for the United States Army coming from Switzerland couldn´t be guaranteed in the moment when they were mostly needed. The clocks were ordered from different factories such as Waltham, Elgin, and Witnauer.
Waltham designed this machine in 1910. The production for this clock took place between 1941 and 1944. The movement has 15 jewels, double spring barrel with power for eight days. It was the last 37 caliber clock built buy Walthman.
The winding and setting knob is situated in the fifteenth hour of the dial, and in its normal position it winds up clockwise, it can be winded up in the opposite way without any consequences. Pulling the knob we can adjust the time. The date is to be adjusted by clicking a small button placed beside the knob and it has a small label saying DATE.
WALTHAM XA
The Waltham XA incorporates a movement with a 37 caliber and 7 jewels.
This movement was submitted to extreme temperature and vibration controls during its certification. Built in the twenties, it was the most reliable clock of its time.
Lindberg chose it for the historical flight, because he preferred accuracy than reliability.
See RYAN NYP, Charles Lindberg famous plane
WALTHAM AN 5743
The AN 5743 was designed for navigation and its purpose was to determine the time on an airplane with great endurance. Walthman built this machine up to 1945. Some had 9 jewels and others had 11. Both could be winded up for eight days.
The green numbers were not visible during the night, while the hands and the small marks between the numbers are painted in a fluorescent color.
This clock equipped the B-24 LIBERATOR and the P-51 MUSTANG.
WALTHAM TYPE A-13A
This is the airplane clock from the Cold War age, the military specifications led to the creation of only one timer clock for the whole Department of Defense, all the US airplanes in this period were equipped with this clock.
All this clocks made under this specifications and requirements, such as having independent chronograph, having a minimum of 15 jewels, at least power for 8 days, or for example, having a variation of 75 seconds in 6 hours at 35 degrees Celsius and many more specifications, are known after the name of A-13.
The waltham A-13A has 22 jewels, and could be found in all US cold war planes from U-2 to C-130 Hercules, and of course in the emblematic F-4 PANTHOM
