Intercept Officers Equipment Kit, Type I (Navigation Computer) 1943 Martin This is an Altimeter used

This is an Altimeter used in military aircraft of the US Navy either during or post WW1

and of the axis nations

It has a service stamp SMAMA (USAF Sacramento Air Materiel Area at McClellan AFB

25 inches diameter and ~2

or patrol observer

Intercept Officers Equipment Kit, Type I (Navigation Computer) 1943 Martin This is an Altimeter usedThis is a WWII era navigation computer in a kit "Intercept Officers Equipment Type I. This example includes two 2 piece USAAF Ground Speed Timer Calculators (for map scales 1: 250,000 and 1: 500,000) and 2 USAAF Rulers. The bottom of the metal case contains a mechanical computer to solve the wind problem. It has a locking mechanism and a movable arm for drift, adjusted for air speed, interconnected to the heading tracker. The lid contains tables and a