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 1,000 feet (300 m). It utilised the same type of input data furnished by a range section with the then-current (1940) 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 (using vacuum tube technology) built byBell Labs and used by coast artillery with medium-caliber guns (up to 8 inches or 200 millimetres). 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.
M10: A ballistics computer, part of the M38 fire control system, forSkysweeper anti-aircraft guns.
The Battery Computer System (BCS)AN/GYK-29 was a computer used by theUnited States Army for computingartillery fire mission data. It replaced the FADAC and was small enough to fit into theHMMWV combat vehicle.
TheAN/GSG-10 TACFIRE (Tactical Fire) direction system automatedfield artillery command and control functions.[8] It was composed of computers and remote devices such as the Variable Format Message Entry Device (VFMED), the AN/PSG-2 Digital Message Device (DMD) and theAN/TPQ-36 Firefinder field artillery target acquisitionradar system linked by digital communications using existing radio and wire communications equipment. Later it also linked with the BCS which had more advanced targeting algorithms.
The last TACFIRE fielding was completed during 1987. Replacement of TACFIRE equipment began during 1994.[citation needed]
TACFIRE used theAN/GYK-12, a second-generation mainframe computer developed primarily byLitton 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 theAdvanced Field Artillery Tactical Data System (AFATDS). The AFATDS is the "Fires XXI" computer system for both tactical and technical fire control. It replaced both BCS (for technical fire solutions) and IFSAS/L-TACFIRE (for tactical fire control) 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 aSun MicrosystemsSPARC computer running theLinux kernel to a version based on laptop computers running theMicrosoft Windows operating system.
One reason for a lack of surviving examples of early units was the use ofradium on the dials. As a result they were classified ashazardous waste and were disposed of by theUnited States Department of Energy. Currently there is one surviving example of FADAC at theFort Sill artillery museum.[9]
^Lieutenant Albert R. Milavec."On FADAC Maintenance"Archived 2013-02-26 at theWayback Machine.p. 32 of"Artillery Trends" May 1968."The FADAC is an all-transistorized, stored-program, general purpose digital computer ...Weighing approximately 200 pounds ...the FADAC components utilize approximately 1,600transistors, 9,000 diodes, 6,000 resistors, 500 capacitors, and many other switches, transformers, and neon lamps."
