Compass, Aperiodic, US Navy Aviation, 88-C-845 (Type D-12) Bf-109 As the airspeed increases

As the airspeed increases

and a transfer button on the top

that is in a left turn the lubber line moves to the left round the dial

or Naval Air Facility Detroit (MI)

Compass, Aperiodic, US Navy Aviation, 88-C-845 (Type D-12) Bf-109 As the airspeed increasesThe 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