Aircraft Instrument Course 1939: The Air Corps Technical School M-41-4 Sally Bomber It has a detector unit

It has a detector unit

The manual is in very good condition despite some discoloration on the cover and some minor deterioration on the upper corner of the last 4 pages

The AAU 19A/A altimeter is a standard 3 inch counter-drum-pointer altimeter which provides two modes of operation -- servoed (reset) mode and standby mode

The floating ball indicator no longer contains damping fluid

Then the gunner may greet the uninvited guest with 50 cal potpourri

Aircraft Instrument Course 1939: The Air Corps Technical School M-41-4 Sally Bomber It has a detector unitDated 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