Unknown Aircraft Clock

[Plant#4]

Here is an unknown to me, aircraft clock. Odd in its placement, dial, and function. Those little hands would be hard to see in a busy cockpit, but its design is unmistakeable. It runs fine, aquried from a long time aircraft engineer and airbird restorer's estate. Any help would be greatly welcomed. 2 inch face Dave

[Plant#4]

and the back. As you can see there is no data tag or markings. I will not open this running clock, even though it would solve several issues, such as who and when. I preferre not to "open" stuff up just to look around. I did notice that I hadnt cleaned it from when I got it, so I dusted it and put it back on the shelf. Dave