Compass, Aperiodic, US Navy Aviation, 88-C-845 (Type D-12)- 2 Seagull This knob is to be

This knob is to be set to the same footage that is indicated in the "unexposed footage" window of the film cartridge

The knob in the lower left corner adjusts the altimeter for the barometric pressure

and maintenance of the PBY flying boat

The clock runs

The threads that would capture the retaining ring may require filing for a smooth fit

Compass, Aperiodic, US Navy Aviation, 88-C-845 (Type D-12)- 2 Seagull This knob is to beThe US Navy 88 C 845 (USAAF Type D 12) Direct Reading Aperiodic Navigational Compass was used at the navigators station across many US Navy WWII aircraft, including patrol bombers PBY Catalina, PB2Y Coronado, PB4 Privateer, PV 1 Ventura and PV 2 Harpoon. Made by Bendix, part number 1828 1 A. The navigators' direct reading compass is known as an aperiodic (without a period) compass, since the needle returns to rest quickly and without appreciable