M1: This was used by seacoast artillery for major-caliber seacoast guns. It computed continuous firing data for a battery of two guns that were separated by not more than. It utilised the same type of input data furnished by a range section with the then-current types of position-finding and fire-control equipment.
M3: This was used in conjunction with the M9 and M10 directors to compute all required firing data, i.e. azimuth, elevation and fuze time. The computations were made continuously, so that the gun was at all times correctly pointed and the fuze correctly timed for firing at any instant. The computer was mounted in the M13 or M14 director trailer.
M4: This was identical to the M3 except for some mechanisms and parts which were altered to allow for different ammunition being used.
M8: This was an electronic computer built by Bell Labs and used by coast artillery with medium-caliber guns. It made the following corrections: wind, drift, earth's rotation, muzzle velocity, air density, height of site and spot corrections.
M9: This was identical to the M8 except for some mechanisms and parts which were altered to accommodate anti-aircraft ammunition and guns.
M18: FADAC, an all-transistorized general-purpose digital computer manufactured by Amelco and North American—Autonetics. FADAC was first fielded in 1960, and was the first semiconductor-baseddigital electronics field-artillery computer.
The Battery Computer System AN/GYK-29 was a computer used by the United States Army for computing artillery fire mission data. It replaced the Field Artillery Digital Automatic Computer and was small enough to fit aboard the HMMWV combat platform.
The AN/GSG-10 TACFIRE system automated Field Artillery command and control functions. It was composed of computers and remote devices such as the Variable Format Message Entry Device, the Digital Message Device and the Firefinder Field Artillery target acquisition radar system linked by digital communications using existing radio and wire communications equipment. Later in its service life, it also linked with the Battery Computer System which had more advanced targeting algorithms.
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 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 AFATDS is the "Fires XXI" computer system for both tactical and technical fire control. It replaced both BCS and IFSAS/L-TACFIRE systems in U.S. Field Artillery organizations, as well as in maneuver fire support elements at the battalion level and higher. As of 2009, the U.S. Army was transitioning from a version based on a Sun MicrosystemsSPARC computer running the Linux kernel to a version based on laptop computers running the Microsoft Windows operating system.
Surviving examples
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.
