Aircraft Instrument Course 1939: The Air Corps Technical School M-41-4

Dated 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 aircraft of the Air Corps US Army and Air Force US Army during WWII. Included are:

• Pressure Gages
• Engine Gage Units
• Tachometers
• Thermometers
• Fuel-Air Ratio Indicators
• Compasses
• Airspeed Indicators
• Altimeters
• Rate of Climb Indicators
• Turn and Bank Indicators
• Directional Gyros
• Gyro Horizons
• Automatic Pilots
• and others

It is clearly experienced, but all of the pages are included.  It is missing its rear cover, and the front cover is loose but present.   It is a wonderful reference document from that era.