M18 FADAC

The gun data computer was a series of artillery computers used by the U.S. Army for coastal artillery, field artillery and antiaircraft artillery applications. In antiaircraft applications they were used in conjunction with a director.

The last TACFIRE fielding was completed in 1987. Replacement of TACFIRE equipment began in 1994.

TACFIRE used the AN/GYK-12, a second-generation mainframe computer developed primarily by Litton Industries for Army Divisional Field Artillery (DIVARTY) units. It had two configurations, division and battalion level, housed in mobile command shelters. Field Artillery Brigades also use the division configuration.

Components of the system were identified using acronyms:

The successor to the TACFIRE system is the Advanced Field Artillery Tactical Data System (AFATDS).

One reason for a lack of surviving examples of early units was the use of radium on the dials, which officially made them hazardous waste, and as such were disposed of by the United States Department of Energy. Currently there is one surviving example of FADAC at the Fort Sill artillery museum.

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