In article , john Szalay
says...

Miloch wrote in
news
In article , Mitchell
Holman says...




Anyone know what the 'doo-hickey' on top of the wing is?





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its a Fairchild Aerial US Navy BuOrd Machine Gun Camera Mark VI


Thanks!...wasn't aware they went back that far.

https://en.wikipedia.org/wiki/Gun_camera

"Gun cameras are cameras used primarily in aircraft to help measure tactical
effectiveness. These cameras are triggered by the firing of a weapon, hence the
name.

"The use of gun cameras first became common for gunnery training in the 1920s
though examples were used during World War I by the British Royal Flying Corps.
A special version of the standard Lewis Machine Gun was manufactured as a Camera
Gun. During World War II, gun cameras were commonly used on operational aircraft
to record kills of enemy aircraft. Some of this footage survives to this day and
is often the source for stock footage in World War II movies, TV shows or video
games.




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