US Army Air Force
General Interchangeability of Aircraft Instruments TO 5-1-3 Sept 1947
This 140-page Technical Order 5-3-1 provides cross-reference interchangeability information for aircraft instruments in use in aircraft of the US Army Air Force and US Navy by its publication in 1945 (revised 1947).
It is a wealth of information for interchangeability of aircraft instruments as the part numbering of instruments evolved with the use of manufacturer's part numbers and type number, over time. Even small changes in instrument design, such as lettering color, changed the manufacturer's part number and the ability for the technician to determine its appropriate use.
Note that this document does not link instruments to specific aircraft. For that purpose, refer to TO 00-45-1 Accessories for Aircraft-Engines Interchangeability Cross Reference Charts, which can be found and downloaded from our Library.
The manual is in exceptional condition given its age.