Aircraft Instrument Course 1939: The Air Corps Technical School M-41-4 Sally Bomber Requires the correct electrical input

Requires the correct electrical input to operate

It has a detector unit

or film spools

"AC US ARMY" is embossed on the face of the instrument (black on black)

Aircraft Instrument Course 1939: The Air Corps Technical School M-41-4 Sally Bomber Requires the correct electrical inputDated September 1, 1939, this pre WWII instructional manual is for the Aircraft Instruments course of The Department of Mechanics in The Air Corps Technical School, M 41 1. Consisting of 258 pages and dozens of illustrations and diagrams, this compendium describes the purposes, uses, descriptions, operations, installation, service, inspection, and maintenance of more than 30 instrument types. The manual covers instruments that were eventually used in