Free Air Temperature Indicator, Direct Reading, Type C-13B WWII C-118 where headphones would likely have

where headphones would likely have been the preferred method of rendering audio to the crew)

indicative of a year of manufacture of 1943

It was a late war innovation that used the aircraft altitude and speed with the direct correlation of where the weapon was pointed to calculate the reticle

B-47 Stratojet

HAYES G-3-217

Free Air Temperature Indicator, Direct Reading, Type C-13B WWII C-118 where headphones would likely haveThis is an authentic vintage Direct Reading Free Air Temperature Indicator Type C 13B, 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 70dC 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