Aircraft Instruments Technical Instructions, Air Corps Technical School, 1939 C-130 unscrew the collar (I) and

unscrew the collar (I) and pull the lamp support assembly straight out

The fluid is discolored and about 2/3rds level

See photo of Tony instrument panel showing the location of this compass from a book by WWII Japanese Aircraft researcher Robert Mikesh

See the windshield parts diagram from its parts list dated December 1955

and paired with one more dual tachometer for engines 3 & 4 in heavy bombers such as B-17 Flying Fortress

Aircraft Instruments Technical Instructions, Air Corps Technical School, 1939 C-130 unscrew the collar (I) andHere is a pre WWII era Technical Instruction reference manual for students of the Air Corps Technical School, published in October 1939, for use in training aircraft instrument technicians of the US Army Air Corps. This 258 page, 8. 5 by 11 inch technical manual covers all of the most commonly used instruments used in aircraft of the era, including pressure, temperature, and quantity gauges, compasses, turn, climb, and airspeed indicators, gyro