Bomb Release Interval Control Panel Type B-2A PZL See diagram of A4D-1 instrument

See diagram of A4D-1 instrument panel from its flight manual dated 1962

the copper

as used in various aircraft of the Air Service US Army

and C-7A Caribou

spaced equally on either side of the N and S markings

Bomb Release Interval Control Panel Type B-2A PZL See diagram of A4D-1 instrumentThis is an original WWII era Bomb Release Interval Control, Type B 2A, as used across nearly all US bomber aircraft, including B 17, B 24, B 25, B 26, and B 29 and any US Navy counterparts. The Bomb Release Interval Control permitted a bombardier to control the number of bombs dropped per release and their impact spacing. This would be used to set up a carpet bombing run, for example, over a large railroad marshalling yard, vs a more concentrated drop