Compass, Aperiodic, US Army Air Force Type D-12 Victor according to their flight manuals

according to their flight manuals from the 1950's

made by Kollsman

This Cold War / Vietnam War era Course Indicator MN-97 Omi-Mag was made by Bendix for use in aircraft of the US military and commercial carriers

See diagram from the UH-1 Flight Manual

According to the US Army Air Force Maintenance Interchangeability Chart dated Feb 1945

Compass, Aperiodic, US Army Air Force Type D-12 Victor according to their flight manualsThe US Army Air Force Type D 12 Direct Reading Aperiodic Compass was used at the navigators station across many US WWII aircraft, including heavy bombers B 17, B 24, B 29, medium bombers B 25 and B 26, and transports C 46, C 47, and C 54. Made by Bendix, part number 1832 1 A, it has a serial number prefix of AF 45, indicative of a manufacturing year 1945. The navigators' direct reading compass is known as an aperiodic (without a period) compass, since