Free Air Temperature Indicator, Direct Reading, Type C-13A WWII AT-6 The E-13 Tachometer was used

The E-13 Tachometer was used in various US fighter aircraft

The crown symbol of the Air Ministry is imprinted on its rear case with its stores reference number

the bellow causes a pen scribe to rise along the strip chart

and the other for Outside pressure/altitude

The markings are clear and the glass and case are intact

Free Air Temperature Indicator, Direct Reading, Type C-13A WWII AT-6 The E-13 Tachometer was usedThis is an authentic vintage Direct Reading Free Air Temperature Indicator Type C 13A, as used in Bombers Boeing B 17 Flying Fortress and Consolidated B 24 Liberator, plus Transport Douglas C 47 Skytrain and others. The instrument indicated to the pilot the aircraft's external air temperature from 60dC to +50dC in aircraft of the Air Force US Army, and would have its stem installed from the cockpit or the bombardier's compartment thru the skin or the