Airspeed Indicator, 300 MPH Kollsman 157-09-6223 F-105 Thunderchief See photo of the location

See photo of the location of the instrument on the air conditioning control panel from the C-121 flight manual dated 1965

but barely discernible in the photos

If he was too far to the left or right

Beam Approach Beacon System – BABS – was a homing device used to help pilots land in poor visibility

the numbers in the small window would rotate and indicate the RPM in 1000's

Airspeed Indicator, 300 MPH Kollsman 157-09-6223 F-105 Thunderchief See photo of the locationHere is an early WWII era Airspeed Indicator, Kollsman part number 157 09 6223 with a maximum airspeed of 300 MPH. It is, or very similar to, the airspeed indicator used in the Beechcraft C 43 Staggerwing of the US Army Air Force, see photo from its flight manual dated 1944 showing the indicator. It is in terrific condition given its age. Measures 3. 25 inches diameter by ~2. 5 inches deep.