ITT 465L Strategic Air Command Control System


At the Offutt AFB nuclear bunker and at March AFB; SACCS had 3 AN/FSQ-31 systems each with a Data Processing Central (DPC), Data Display System (DDS), and Data Transmission Subsystem (DTS)[1] (Barksdale AFB didn't have a DPC.) The DCS consisted of an Encryption/Decryption Subsystem, High Speed Data Transmission Equipment (Modems), and an Electronic Data Transmission Control Center (EDTCC) with secure voice units and Technical Control Consoles (TCCs)--SACCS "voice transmission [was] by patching 4-wire telephone terminating equipment on the circuit at each end.[1] NORAD's 1963 Chidlaw Building Combined Operations Center, then Cheyenne Mountain Complex in 1966 (top left), received SAC data (e.g., to allow relay of messages through northern NORAD radar stations for recalling SAC bombers.)

In 1965, RCCs were at 13 "operational base command posts" (duplexed from different EDTCCs except for 4 RCCs with "short order sites"), and SRCCs were at 2 "missile site alternate command posts"—RCCs/SRCCs had a "Fault and Facility Control Panel.". One Offutt EDTCC communicated with 1 SRCC and 6 RCCs (with 2 circuits to the 1 local RCC), while the other Offutt EDTCC only had circuits to 4 RCCs (2 bomber, 2 ICBM). At the Numbered Air Force bases, circuits from one EDTCC were to 7 RCCs, and the other connected to 5 RCCs and 1 missile SRCC.[1]

System Development Corporation (SDC) also built a Simulation Facility (SIMFAC) in Paramus, New Jersey to model the SAC Command Post using "Command/Control personnel stations, capabilities to produce simulated SACCS hardware printouts…wall displays [and] a soundproof observation deck [booth] in which SIMFAC personnel perform actions necessary to simulate all external occurrences starting from an Intelligence buildup to changes in threat responses"[2]--the 50 ft × 35 ft (15 m × 11 m) "isolation booth" was completed in 1962 by International Electric Corporation.[3]

The ITT 465L Strategic Air Command Control System (SACCS, SAC Control System, 465L Project,[1] 465L Program) was a Cold War "Big L"[4] network of computer and communication systems for command and control of Strategic Air Command "combat aircraft, refueling tankers, [and] ballistic missiles".[3] International Telephone and Telegraph was the prime contractor for Project 465,[5] and SACCS had "Cross Tell Links" between command posts at Offutt AFB, March AFB, & Barksdale AFB (SACCS also communicated with the Cheyenne Mountain Complex and Air Force command posts. The 465L System included IBM AN/FSQ-31 SAC Data Processing Systems, Remote (RCC) and Simplex Remote Communication Systems (SRCC), SAC Network Control Office, "4-wire, Schedule 4, Type 4B alternate voice-data operation", and one-way communication with "ICBM launch control centers"[1] (the SAC Digital Network upgraded to two-way communications.) In addition to IBM for the "Super SAGE type computers", another of the 6 direct subcontractors[5] was AT&T ("end-to-end control" of the communications circuits),[1]


Strategic Air Command began using the telephonic Army Command and Administrative Net (ACAN) in 1946 until switching to the 1949 USAF AIRCOMNET "command teletype network" (the independent Strategic Operational Control System or SOCS with telephones and teletype was "fully installed by 1 May 1950".)[6]: 77  SACE deployed a worldwide communications network in 1958 with a day-to-day telephone system, a teletype system, an SSB HF system, and the Primary Alert System[7]--"a direct line telephone system between the SAC underground command post and all its subordinate command and control centers (numbered air force and wing command posts)."[8]

1st IBM "Big L" system
In 1955 the Experimental SAGE Subsector was completed with a simplex IBM XD-1 prototype of the AN/FSQ-7 planned for the SAGE computer network,[9] and IBM Federal Systems subsequently built dozens of vacuum tube computers for the AN/FSQ-8 and AN/FSQ-7 centrals of Support System 416L (SS-416L),[10] the 1st "Big L" system. SAGE radar stations used AN/FST-2 sets for transferring data, and GATR sites and BOMARC Ground-to-Air Transmitter Facilities provided radio control for ground-controlled interception. An IBM AN/FSQ-32 transistorized SAGE central was announced in June 1958[11] and was to planned for in several NORAD nuclear bunkers, but the Super Combat Centers were cancelled in 196x. The transistorized central "was given to SDC to be used for the ARPA command-control R&D program", and the USAF "later[when?] took back [the Q-32] from SDC to SAC HQ at Omaha" for the "ADEPT…status reporting system".[12]

In 1956, CINCSAC[13] determined SAC's leased teleprinter (teletype) circuits and radio links were too slow,[14][failed verification] and SAC began using a computer in 1957.[15] A SAC Liaison Team was located at the NORAD command post beginning 1 February 1958, and the 2 commands agreed direct land lines should connect SAC bases and Air Defense Direction Centers.[16] After CONAD designated 3 "SAC Base Complexes" (geographical areas) by 1956--Northwestern United States, Montana-through-North Dakota area, and the largest: a nearly-triangular "South Central Area" from Minnesota to New Mexico to Northern Florida[17]—NORAD's Alert Network Number 1 became operational on July 1, 1958, with the 1957 SAC nuclear bunker as 1 of the network's 29 transmit/receive stations.[18]


On February 11, 1958, Headquarters USAF published General Operational Requirement or GOR 168 for SACCS[19] (the Westover AFB command post was to get a computer system)[5] and on April 1, HQ USAF changed the SACCS designator from Program 133L to 465L.[20] SAC's QOR for the National Survivable Communications System (NSCS) was issued September 13, 1958,[7]: 175  and in October 1959 the systems cost had increased from $139.7 million to $339.8 million in 12 months: the Office of the Secretary of Defense—with "doubts regarding the validity of the entire 465L concept"—cut the program by December 1.[7] In September 1960 the "installation of a SAC display warning system" included 3 consoles (e.g., BMEWS Display Information Processor (DIP) in the Offutt bunker[7]: 218  and on 7 December I960, the 465L Program was cut to ""a most austere approach"[7] (an austere air defense sector was also established for NORAD, which soon planned a smaller BUIC control system.) "In July 1961, the Department of Defense redirected SACCS 465L to a pre-strike system and established a separate [airborne] post-attack command control system with air and ground elements.[7]

by 1962, "SAC installations, inclusive of those overseas and of tenant bases, peaked at 85".[21] "Project 465L, the SAC Control System (SACCS) [with] over a million lines, reached four times the size of the SAGE code and consumed 1,400 man-years of programming; SDC invented a major computer language, JOVIAL, specifically for this project."[4]

SACCS "was delivered to Strategic Air Command by the contractor in March 1965"[15] and was designed to survive nuclear attack and to provide rapid transmission, processing, and display of information to support command and control of SAC's geographically separated forces.[14] On January 1, 1968, the SACCS attained operational capability[22] (maintenance at Offutt and March were by the respective 55th Strategic and 33rd[23] Communications Squadrons.) During construction of NORAD's nuclear bunker, SAC's 1963 plan for construction of a Deep Underground Command Center in Colorado beginning in 1965 was cancelled.

In 1968, "after SAC completed its tests during March, AFSC arranged for modification of the SAC terminals for use with LES-6" for satellite communications.[24] A SACCS remote communications van[specify] completed on 12 July 1968 was shipped to Andersen AFB, Guam,[25] e.g., for supporting the SACADVON (30 SAC B-52s had deployed on 17 February 1965 to Guam for the Vietnam War.)[26]

Gradual replacement

On October 6, 1975, SACCS officially integrated with the Worldwide Military Command and Control System when the original IBM 4020 Military Computers were replaced by Honeywell 6080 computers (remaining FSQ-31 components were entirely decommissioned in November.)[citation needed] Offutt became part of the WWMCCS Intercomputer Network as one of "six initial WIN sites in 1977" (20 sites by 1981).[27] A 1977 plan was for SACCS to be replaced by the ITT[28] SAC Automated Total Information Network (SATIN IV), "a totally new command and control system "[29] (ITT had won the initial SATIN IV contract over Sylvania.)[30]

Replaced DTS

Instead of SATIN IV, a restructured plan deployed the Strategic Air Command Digital Information Network to replace SACCS "Data Transmission Subsystem and part of the Data Display Subsystem",[31] e.g., on November 5, 1986, "Martin Marietta Corporation technicians began installing SAC Digital Network (SACDIN) equipment in 91st Strategic Missile Wing missile launch control centers[32] (i.e., either a HUTE rack or MBCP rack).[33] On February 20, 1987, "SAC declared initial operational capability for the SAC Digital Network when [it] operated successfully between the Headquarters SAC Command Center and the 55th Strategic Reconnaissance Wing Command Post, both located at Offutt AFB, Nebraska, and the 351st Strategic Missile Wing Command Post at Whiteman AFB, Missouri."[32] SACDIN eventually "linked 135 locations and permitted two-way message communications with ICBM launch control centers for the first time,"[32] and the Ground Wave Emergency Network communication system had a Final Environmental Impact Statement issued in September 1987.[34]

On May 6, 1988, "software became operational on three Post Attack Command and Control aircraft making the common Airborne Launch Control Center fully capable of launching Peacekeeper and Minuteman missiles."[32]

SAC Automated Command and Control System

In 1990 when the 465L System had been entirely replaced by the "SAC Auto Cmd/Ctl Sys"[35] for several years, the SAC C2 system continued using that name as part (except for the SACCS Data Processing System) of "USSTRATCOM Command and Control" (PE 0101316F).[36] By 1995, the "emergency war order (EWO) communication systems consist[ed] of the primary alert system (PAS), SAC digital network (SACDIN), survivable low frequency communication system (SLFCS), Air Force satellite communications system (AFSATCOM), [ICBM] Super High Frequency Satellite Terminal (ISST) and [UHF] voice radio communication systems"[33] The USSTRATCOM SACCS was redesignated[when?] Strategic Automated Command and Control System with the same acronym on tbd\[specify] and by 2011, the Minimum Essential Emergency Communications Network was being modernized in the Nuclear Command and Control System.[37] By February 2012, USSTRATCOM was using the Integrated Strategic Planning and Analysis Network (ISPAN), and the USSTRATCOM Replacement Facility Fit-Out (PE 0303255F) was to "include secure HEMP-Shielded Command and Control Center, mainframe computer data centers, multiple 24/7 mission operations centers, storage and maintenance areas, labs/workrooms, back-up generators, Uninterruptible Power Source, Technical Control Facility, Fiber Ring, [with funding] beginning in FY13."[38]

External media
image icon 465L communication diagram (Fig. 1)
image icon prototype EDTCC at ITT test site
video icon SAC Command Post (at minute 5:25)


  1. ^ a b c d e f "Strategic Air Command Control System (SACCS): Description and Service Maintenance", Private Line Data Systems: Special Data Networks, Plant Series, American Telephone and Telegraph Company, July 1965, Section 314-411-504 (SACCS Description and Service Maintenance section), retrieved 2014-05-12, This section covers description, administrative procedures and maintenance requirements for the Strategic Air Command Control System (SACCS). This system was initially known as the 465L Project. … The customer may use the circuits for voice transmission when desired by patching 4-wire telephone terminating equipment on the circuit at each end. Signaling equipment is added with the telephone set at EDTCCS. Circuits from EDTCCS terminating at RCCS and SRCCS are provided with signal receiving equipment A 1600 cps tone is used for signaling from an EDTCC. No means of signaling is provided from an RCC or SRCC to an EDTCC. … Circuits which interconnect headquarters locations with operational bases and missile complexes or other headquarters locations… Over-all administration of these circuits is handled by the SAC Network Control Office. [cf. SAC Communications Control] … An RCC is the customer’s data equipment location at an operational base command post. RCCS are normally connected by data circuits to two different EDTCCS.
  2. ^ Antaccs Project (Midway Report) (Report). July 1964. Retrieved 2014-04-02. "In support of its design and development responsibilities in the Strategic Air Command Control System (SACCS) project, SOC established a Simulation Facility (SIMFAC) in Paramus, New Jersey. The SIMFAC is a physical model of the SAC Underground Command Post complete with Command/Control personnel stations, capabil ities to produce simulated SACCS hardware printouts and wall displays. There is a soundproof observation deck in which SIMFAC personnel perform actions necessary to simulate all external occurrences starting from an Intell igence buildup to changes in threat responses. (text-only copy available at
  3. ^ a b "tbd" ( character recognition text). European Stars and Stripes. March 3, 1962. Retrieved 2014-05-09. Nearly $413,000 was contribute.*:by military and civilian personnel!!in the European area. … Data Displays Being Tested In SAC Booth PARAMUS, N.J. (Special) — On«rof the world's largest "isolation*booths" is being used here toequipment and man's mentalers in handling the forecast,lem of keeping track of the Strate*gic Air Comd battle forcevarious simulated combattions. •'•'?.Built by International Electric;?Corp., a subsidiary of International;Telephone and Telegraph Cbrp.^;the booth incorporates two-way;mirrors, hidden microphones and,tape recorders. '-jFifty-feet long and 35-feet wlde,-^the booth is called Simfac (for":simulation facility) and is to J>eused in connection with a proposedworking model of a new SAC com-mand control system developedhere by IEC.Known as SACCS, the command,control system will be a fully auto-mated, electronic computer net-work which will keep tab on SAC'*combat aircraft, refueling tankers,ballistic missiles and 270,000 memAlso, It will display up-to-the-'minute, force status on 16 wall-sizeprojection screens at commandheadquarters.StatisticsThe problem is one of matingman's capability to that of a ma-chine.That is, how much visually-dis-played information can SAC con-trollers absorb at one time; howfast can they find a specific num-ber of 20, 40. or 50; do colored dis-plays help or hinder them, andwill the staff operate less efficient-ly if given too much data at onetime?These and other questions arebeing studied by IEC psychologists* rhuman engineers and researchers^in the closely controlled laboratoryconditions of Simfac.(subscription required)
  4. ^ a b Edwards, Paul N (1997). "SAGE". The Closed World: Computers and the Politics of Discourse in Cold War America. ISBN 9780262550284. Retrieved 2014-05-14. SAGE--Air Force project 416L--became the pattern for at least twenty-five other major military command-control systems… These were the so-called "Big L" systems [and] included 425L, the NORAD system; 438L, the Air Force Intelligence Data Handling System; and 474L, the Ballistic Missile Early Warning System (BMEWS).
  5. ^ a b c "New Applications: Command Control System -- Project 465L" (PDF). Computers and Automation. 10 -- No. 12. August 1964. Retrieved 2020-09-05. The system makes a 70mm positive film of the information. Three images of each message appear on the film, and a powerful beam of light carries them about 30 feet to the screen. Before striking the film, however, the light beam is split into the three primary colors by special mirrors. Combining these colors, gives the display system a color code of seven distinct colors for easy recognition of various types of information. The complete cycle, from display request to projected image, requires less than 15 seconds. … Data Processing Central (DPC) , Project 465L, Prototype Equipment located at the ITT Data and Information Systems Division test facility. … Display equipment will be installed at Offutt AFB; March AFB, Calif.; Westover AFB, Mass.; and Barksdale AFB, La.; any of the four will be able to serve as a fully equipped SAC central headquarters at any time. … As late as 1957, the first widely accepted programming system, FORTRAN, was released for the IBM 704.
  6. ^ Wainstein, L. (June 1975). The Evolution of U.S. Strategic Command and Control and Warning: Part One (1945-1953) (Report). Study S-467. Institute for Defense Analyses. pp. 1–138.
  7. ^ a b c d e f Moriarty, J. K. (June 1975). The Evolution of U.S. Strategic Command and Control and Warning: Part Two (1954-1960) (Report). Study S-467. Institute for Defense Analyses. pp. 139–266.
  8. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2014-05-18. Retrieved 2014-10-02.CS1 maint: archived copy as title (link) "One of the first is the SAC Communications System, [sic] now the Strategic Automated Command and Control System (SACCS)… The 279L system, originally with Blue Scout missiles based in Nebraska, and later with modified Minuteman II missiles, used UHF transmitters in the missile payload sections. It became known as the Emergency Rocket Communications System (ERCS). …responsibility to be the Missile Radio Communications System (MRCS) station for the wing or squadron was passed between LCCs periodically"
  9. ^ "Vigilance and Vacuum Tubes: The SAGE System 1956-63" (SAGE Talk Transcript). 1998. Retrieved 2013-02-16. the Whirlwind computer, which was a digital version of the ASCA, was about five million dollars, in 1950’s [sic] dollars … For the 1949 fiscal year, MIT requested 1.5 million dollars for the Whirlwind project. … one [SAGE computer] was at Lincoln Lab, …the XD-1, and the other one was at Kingston, the XD-2. So we used both those sites for development. … The XD-1 was a simplex system…not duplex … the original vacuum-tube computers—the last one was finally taken down in 1983, still operating. … IBM got…about 500 million dollars…to build the 56 computers.
  10. ^ "Designations Of U.S. Air Force Projects".
  11. ^ Schaffel, Kenneth (1991). Emerging Shield: The Air Force and the Evolution of Continental Air Defense 1945-1960 (45MB pdf). General Histories (Report). Office of Air Force History. ISBN 0-912799-60-9. Retrieved 2011-09-26.
  12. ^ "ADEPT, which accepted nearly natural-language computer commands and which could be operated initially on the time-sharing IBM 360/67's and later on other computers. ADEPT incorporated special provisions for security, and beginning in 1968 was used for some time at the National Command Center (NCC) and the Air Force Command Center. SAC also used ADEPT for its status reporting system, for which it later took back the Q-32 computer from SDC to SAC HQ at Omaha.39"
  13. ^ "Strategic Automated Command Control System". Global Retrieved 2014-05-13. In 1956, Gen. Curtis LeMay, commander-in-chief of SAC, saw a need for improving SAC's command and control system. A coordinated effort was undertaken by government and industry to provide this system. The project was designated 465L, and was the predecessor to the current Strategic Automated Command Control System network. In the mid-1960s, SAC procured the 465L system
  14. ^ a b "Strategic Automated Command Control System". Federation of American Scientists. 1999. Retrieved 2006-06-20.
  15. ^ a b Wohlman, John (1968). "Computer-Generated Map Data: An Aid to Command and Control" (webpage transcript). Air University Review. Retrieved June 20, 2006. Cite journal requires |journal= (help)
  16. ^ Preface by Buss, L. H. (Director) (1 November 1959). North American Air Defense Command and Continental Air Defense Command Historical Summary: January–June 1959 (Report). Directorate of Command History: Office of Information Services.
  17. ^ Maloney, Sean M. (1 January 2007). Learning to Love the Bomb: Canada's Nuclear Weapons During the Cold War. Potomac Books, Inc. ISBN 9781574886160 – via Google Books.
  18. ^ Preface by Buss, L. H. (Director) (1 October 1958). North American Air Defense Command Historical Summary: January–June 1958 (Report). Directorate of Command History: Office of Information Services.
  19. ^ Strategic Air Command: "Study of SAC Communications System", 6 February 1958
  20. ^ This was cited using "Ibid"[where?] under the citation for Study of SAC Communications System
  21. ^ Weitze, Karen J. (November 1999). Cold War Infrastructure for Strategic Air Command: The Bomber Mission (PDF) (Report). United States Army Corps of Engineers. Retrieved 2013-08-15.
  22. ^ "History of Strategic Air Command: January–June 1968"[full citation needed]
  23. ^
  24. ^ The Air Force in Space Fiscal Year 1968, Part I (PDF) (Report). October 1970.
  25. ^ Air Force Historical Research Agency: "History of the 3902d Air Base Wing, July - September 1968", pg 40[full citation needed]
  26. ^ Worden, Col Mike (July 2000) [March 1998]. Rise of the Fighter Generals: The Problem of Air Force Leadership 1945–1982 (Report). Air University Press. p. 174. ISBN 1-58566-048-5. Retrieved 2013-08-30.
  27. ^ "ALERT" (PDF).
  28. ^ Archived 2016-11-28 at the Wayback Machine
  29. ^ Currie, Dr. Malcolm R (18 January 1977). The Department of Defense Program of Research, Development, Test and Evaluation, FY 1978 (Report to the Congress). p. V-5 (pdf 239).
  30. ^ United States General Accounting Office (1979). Decisions of the Comptroller General of the United States, Volume 57. Washington, DC: U.S. Government Printing Office. p. 737.
  31. ^ "Histories of Subordinate Units Reporting Directly to the Strategic Communications Division", 1 January - 31 December 1982, Vol 4 of 41
  32. ^ a b c d Clark, Major Rita F (1 May 1990). SAC Missile Chronology 1939–1988 (PDF) (Report). Office of the Historian, HQ. SAC, Offutt AFB. Retrieved 2013-09-26. 1958…1 January Headquarters SAC established the Office of Assistant CINCSAC (SAC MIKE) at Inglewood, California. This position was designated to serve as an extenstion of Headquarters SAC and was responsible for working closely with the Air Force Ballistic Missile Division … 1966…17 April The first attempted launch of a Minuteman II ICBM by means of the Airborne Launch Control System (ALCS)
  33. ^ a b Technical Manual, Operation Instructions, Communication and Ancillary Equipment, USAF ICBM Systems, 21 Nov 1995, Section 1 (PDF) (Technical Order), Change 14 identifies SLFCS, AFSAT II, etc., retrieved 2014-05-12, The single SACDIN cabinet at PLCCs is the communications processor set (HUTE rack). … SAC Digital Network System
  34. ^ Council, National Research; Studies, Division on Earth Life; Sciences, Commission on Life; Research, Board on Radiation Effects; (Gwen), Committee on Assessment of the Possible Health Effects of Ground Wave Emergency Network (1993). Introduction - Assessment of the Possible Health Effects of Ground Wave Emergency Network - The National Academies Press. doi:10.17226/2046. ISBN 978-0-309-04777-7. PMID 24967486.
  35. ^ Hutzler, Patricia L. (April 1990). Defense Planning and Programming Categories: A Special Tool for Special Needs (PDF) (Report). Volume 3. Appendix E, Proposed Expanded DPPC Structure. Logistics Management Institute. Retrieved 2014-05-18. |volume= has extra text (help)
  36. ^
  37. ^
  38. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2014-11-27. Retrieved 2014-05-18.CS1 maint: archived copy as title (link)