Free Air Temperature Indicator, Type C-8 US Army Air Corps Weston 728 T-20 Korean War or transport aircraft such as

or transport aircraft such as the C-46 or C-47

Type 98 Otu

The periscope would be positioned to view the terrain directly below the fuselage while in flight

Used across many versions of US Army Air Force aircraft during the era

the flight engineer controlled the degree to which each engine's intercooler flaps were open and thus managed the carburetor air temperature

Free Air Temperature Indicator, Type C-8 US Army Air Corps Weston 728 T-20 Korean War or transport aircraft such asThis is an exceptional example of the WWII era electrical Free (i. e., ambient) Air Temperature Indicator, US Army Air Corps Type C 8, as used in versions of the heavy bomber B 24 (see photo of instrument panel from a B 24 Flight Manual showing the location of the indicator), also medium bombers B 25 C D Mitchell and B 26 B C Marauder, transports C 87 and C 45, and trainers AT 7 and AT 11, according to the Maintenance Interchangeability Cross