Altimeter, Type MA-1 P-51 It measured the fuel quantity

It measured the fuel quantity in the two front center tanks and two rear center tanks

as well as a hand-written electrical diagram

This is a triple Trim Tab Position Indicator

It covers the development and basic principles of instruments used in the era

It has a serial number prefix of AF43

Altimeter, Type MA-1 P-51 It measured the fuel quantityThis is a Cold War Vietnam War era Altimeter, Type MA 1, made by Aerosonic, part number A 80 MA, used in aircraft of the US Air Force such as fighters F 86 Sabrejet, F 100 Super Sabre, and F 104 Starfighter. MA 1's were also used in UH 1 Huey Helicopters. This example has a serial number prefix of AF 58, likely made for an Air Force order in 1958. The knob in the lower left corner adjusts the altimeter for the barometric pressure, as indicated in the