Description
Technical Manual Change 2 (TM 9-1220-221-20P) for M18 Gun Direction Computer October 1965
This Technical Manual Change 2 for TM 9-1220-221-20P covers the M18 Gun Direction Computer and is dated October 18, 1965.
The publication is an official update to the Organizational Maintenance Repair Parts and Special Tool Lists manual issued on November 14, 1962. Change 2 supersedes Change 1 dated July 7, 1964 and is not the complete base manual.
Historical Significance
The M18 Gun Direction Computer, commonly known as FADAC, was one of the U.S. Army’s early field-deployable digital computers. FADAC stands for Field Artillery Digital Automatic Computer.
The M18 calculated cannon and rocket artillery firing data using battery, target, ammunition, meteorological, and other ballistic information. Its modular electronic construction incorporated replaceable plug-in circuit boards that authorized maintenance organizations could stock and exchange to support the computer.
What This Manual Covers
Change 2 revises the organizational-maintenance repair-parts information for the M18 Gun Direction Computer.
The notice specifically:
- Supersedes Change 1 dated July 7, 1964
- Replaces the footnote governing plug-in circuit boards
- Specifies that plug-in circuit boards are authorized solely for supporting the M18
- Revises repair-parts table headings
- Updates the 15-day maintenance-allowance columns
- Deletes the air cleaner identified by FSN 1290-970-8664
- Revises the amplifier entry identified by FSN 1220-861-7102
- Revises the capacitor entry identified by FSN 1220-620-0142
- Revises the clock entry identified by FSN 1220-862-0019
- Adds updated instructions for submitting errors and recommendations
The notice contains only the October 1965 revisions and supplements rather than replaces the complete TM 9-1220-221-20P base publication.
Key Features
- Official publication number: Change 2 to TM 9-1220-221-20P
- Change publication date: October 18, 1965
- Original manual date: November 14, 1962
- Superseded change: Change 1 dated July 7, 1964
- Equipment covered: M18 Gun Direction Computer
- Common designation: FADAC
- Publication type: official technical manual change notice
- Maintenance scope: organizational repair parts and special tools
- Published by: Headquarters, Department of the Army
Why This Manual Matters
Change 2 documents revised parts allowances and supply information for the M18 FADAC. It provides a focused record of how the Army updated organizational maintenance support for replaceable electronic assemblies in an early digital field computer.
The notice is also useful for bringing an original November 1962 TM 9-1220-221-20P manual up to the October 1965 revision level.
About This Manual
Published by Headquarters, Department of the Army in Washington, D.C., on October 18, 1965, this is Change 2 to TM 9-1220-221-20P.
It updates the Organizational Maintenance Repair Parts and Special Tool Lists manual for the M18 Gun Direction Computer issued on November 14, 1962. This item is the official Change 2 notice, supersedes Change 1, and is not the complete base publication.
Ideal For
This technical manual change is a strong fit for:
- U.S. Army technical-manual collectors
- M18 FADAC restoration projects
- Field artillery and fire-direction researchers
- Military-computer historians
- Vietnam-era artillery collections
- Collectors completing a TM 9-1220-221-20P manual set
- Military museums and reference libraries
Approx length 8", Approx width 10", Approx height .1", Approx weight .2lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item's general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
Please visit our page about order lead times here: Order Lead Times