Intercept Officers Equipment Kit, Type I (Navigation Computer) 1943 Martin or patrol observer

or patrol observer

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

at USAF SBAMA (San Bernadino CA Air Materiel Area)

with an interesting history

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

Intercept Officers Equipment Kit, Type I (Navigation Computer) 1943 Martin or patrol observerThis 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