Navigational Computer, Radar, Doppler, XN-1/APN-67 US Navy C-119 The instrument contains a bellows

The instrument contains a bellows for measuring change in altitude/barometric pressure and a rotating strip chart recorder drum

dated Oct 1943 revised July 1948

It typically was installed in the pedestal to the right of the pilot

The green & red tape markings on the glass indicate the max limits for the aircraft in which it had been installed

This Fuel Quantity Indicator displays fuel quantity from 0-600 lbs (~90 gal)

Navigational Computer, Radar, Doppler, XN-1/APN-67 US Navy C-119 The instrument contains a bellowsNow here's a very interesting instrument for our aeronautical navigation historians: The XN 1 APN 67 was a development stage (XN 1 = Experimental Navy, Series 1) navigational computer used in a Doppler radar system in the early 1950's, designed by Ryan Aeronautical, tested in the US Navy's P 2 Neptune, intended for the P6M 1 Seamaster, and eventually used during "Project Magnet" in the R5D Skymaster and the Lockheed NC 121. The computer measures ~8