AN/FSQ-31 SAC Data Processing System
US Air Force command, control, and coordination system
The IBM AN/FSQ-31 SAC Data Processing System (FSQ-31, Q-31, colloq.) was a USAF command, control, and coordination system for the Cold War Strategic Air Command (SAC). IBM's Federal Systems Division was the prime contractor for the AN/FSQ-31s, which were part of the TBD 465L SAC Automated Command and Control System (SACCS), a "Big L" system of systems (cf. 416L SAGE & 474L BMEWS) which had numerous sites throughout the Continental United States: "all SAC command posts and missile Launch Control Centers" (e.g., The Notch), a communication network, etc.; and the several FSQ-31 sites including:
Offutt AFB's "Headquarters SAC Command Center" (DPC 1 & DPC 2 units)
Combat Operations Center, Fifteenth Air Force, at March AFB (DPC 3),
Barksdale AFB by March 1983.
The FSQ-31 provided data to a site's Data Display Central (DDC) "a wall display" (e.g., Iconorama), and it arrived at Offutt in 1960. On 20 February 1987, "SAC declared initial operational capability for the SAC Digital Network [which] upgraded the SAC Automated Command and Control system "
In accordance with the Joint Electronics Type Designation System (JETDS), the "AN/FSQ-31" designation represents the 31st design of an Army-Navy electronic device for fixed special combination system. The JETDS system also now is used to name all Department of Defense electronic systems.
Description
The FSQ-31 included:
IBM 4020 Military Computer with Programming and Numerical System and "Arithmetic Unit including storage access", liquid-cooled Ferrite Core storage (65,536 words), High-Speed Input/Output to the Drum Memory system, and the Low-Speed Input/Output section to interface with several different devices:
Electronic Data Transmission Communications Central (EDTCC) at 4 "zone-of-interior headquarters bases" for EDT with "outlying" Remote Communications Centrals (e.g., routing "to RCC's, computer (DPC's), or the display devices.")
Tape Controllers 1 and 2, connected to 16 IBM 729-V Tape Drives
Disk File Controller, which was a modified Tape Controller, connected to the
Bryant PH 2000 Disk File, which had 24 disks that were 39 inches in diameter, 125 read/write heads that were hydraulically actuated, and had a total capacity of 26 MB
IBM 1401, which controlled data transfers from unit-record equipment:
IBM 1402 Card Reader/Punch
IBM 1403 Line Printer
2 IBM 729-V Tape Drives
2 IBM Selectric Typewriters, (I/O Typewriters) one of which was used for operational messages and the other for diagnostic messages and maintenance activities.
Advanced Display Console
Drum memory system with controller and two vertical drum memory devices. Each drum read and wrote 50 bits at a time in parallel so transferring data could be done quickly. The drums were organized as 17 fields with 8192 words per field for a total capacity of 139264 words.
The public source identifies “AN/FSQ-31 SAC Data Processing System” as uS Air Force command, control, and coordination system. This brief keeps that definition visible, then builds a research path around FSQ-31, Data and Processing.
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This entry incorporates text from “AN/FSQ-31 SAC Data Processing System” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.