Ballistic Missile Early Warning System

From Infogalactic: the planetary knowledge core
(Redirected from BMEWS)
Jump to: navigation, search

<templatestyles src="Module:Hatnote/styles.css"></templatestyles>

For preceding northern radar networks for detecting Soviet bombers, see Pinetree Line, Mid-Canada Line, and DEW Line.

Lua error in package.lua at line 80: module 'strict' not found.

Ballistic Missile Early Warning System
radar network
Ballistic Missile Early Warning System at Clear AFS (diagram).png
Sketch of Clear Air Force Station BMEWS radars which were replaced by a SSPARS[1] constructed April 16, 1998-February 1, 2001.[1]
System Originator United States
Location BMEWS Central Computer and Display Facility
 - coordinates Lua error in package.lua at line 80: module 'strict' not found. 'in Colorado

Site I*: Lua error in package.lua at line 80: module 'strict' not found. in Greenland
Site II*:Lua error in package.lua at line 80: module 'strict' not found. in Alaska (71st Det 2[2]) Site III: Lua error in package.lua at line 80: module 'strict' not found. in Yorkshire (71st Det 1[3])
Lua error in package.lua at line 80: module 'strict' not found. on Trinidad
    -- site for FPS-50 prototype[4]:{{{3}}} (AN/FPS-43)[5]:{{{3}}}
Lua error in package.lua at line 80: module 'strict' not found. in New Jersey (9th Det 3[6]:{{{3}}})
    -- site for 1959-76[7] FPS-49 prototype[5]:{{{3}}} and test/training[8]:{{{3}}}
tbd BMEWS test facility in New York
System
Prime
Contractor		 RCA Defense Electronics Products[8]:{{{3}}}:29 was contracted in
January 1958[9]:{{{3}}} and "employed 485 large companies and
2415 smaller firms spread over 29 states"[10]
($474,831,000 contract in February 1960)[2]
Constructed 1958-61[11] (complete FOC was January 15, 1964)[12]:{{{3}}}
*Air Defense Command radar stations (cf. ADC general surveillance stations)

The RCA 474L Ballistic Missile Early Warning System (BMEWS, "474L System",[13]:{{{3}}} Project 474L) was a USAF "Big L"[14] Cold War system of radar, computer, and communications systems that included the first operational ballistic missile detection radar.[citation needed] The network of 12 radars[4]:{{{3}}} for detecting "a mass ballistic missile attack launched on northern approaches [for] 15 to 25 minutes warning time"[15] also provided Project Space Track[16] satellite data (e.g., about 1/4 of SPADATS observations).[17]

Equipment

BMEWS consisted of two types of radars and various computer and reporting systems to support them. The first type of radar consisted of very large, fixed rectangular partial-parabolic reflectors with two primary feed points. They produced two fan-like signals that allowed them to detect targets across a very wide horizontal front at two narrow vertical angles. These were used to provide wide-front coverage of missiles rising into their radar horizon, and by tracking them at two points as they climbed, enough information to determine their rough trajectory. The second type of radar was used for fine tracking of selected targets, and consisted of a very large steerable parabolic reflector under a large radome. These radars provided high-resolution angular and ranging information that was fed to a computer for rapid calculation of the probable impact points of the missile warheads. The systems were upgraded several times over their lifetime, replacing the mechanically scanned systems with phased-array radar that could perform both roles at the same time.

Three of the huge AN/FPS-50 radars, BMEWS Site 2, near Anderson, Alaska, in 1962.

BMEWS equipment included:[18]

  • General Electric AN/FPS-50 Radar Set, a UHF (440 MHz) detector with transmitter having an organ-pipe-scanner feed, fixed 1,500 ton [3] parabolic-torus reflector, and receiver with Doppler filter bank to scan with 2 horizontally-sweeping fan[4]:{{{3}}} for as many as ~12,000 observations per day[5]:{{{3}}} for surveillance (determining range, position, and range rate) of space objects[19]
  • RCA AN/FPS-49 Radar Set, a five-horn monopulse tracker (e.g., 3 at Site III) and FPS-49A variant (different radome) at Thule[20] ("vacuum tubes 10 feet tall [in] transmitter buildings [are] used to warm" the site.)[21]
  • RCA AN/FPS-92 Radar Set, an upgraded FPS-49 "featuring more elaborate receiver circuits and hydrostatic bearings"[5]:{{{3}}} at Clear [4]
  • Sylvania AN/FSQ-53 Radar Monitoring Set, with console and Signal Data Converter Group [5] ("data take-off unit")[6]
  • Sylvania AN/FSQ-28 Missile Impact Predictor Set, with duplex IBM-709-TX solid-state computers e.g., in Building 2 at Thule [7] and part of the AN/FPA-21's [8] Radar Central Computer at Site III[22]—Satellite Information Processor (SIP) software was later added at Site III for use on the backup IBM 7090.[9][23]
  • RCA Communications Data Processor (CDP),[24] as used in the Western Electric Air Force Communications Network (AF DATACOM) of AUTODIN[8]:21
  • Western Electric[25]:{{{3}}} BMEWS Rearward Communications System, a "network to link the separate elements"[18]:{{{3}}}[26] and 1 of 6 ADC comm systems: "BMEWS Rearward Long-Lines System"[27] at CFS Resolution Island[28] & CFS Saglek,[29] (cf. Pole Vault Line, White Alice in Alaska,[8]:{{{3}}} and to Fylingdales, NARS)
  • BMEWS Central Computer and Display Facility (CC&DF)[30]:{{{3}}} at Ent AFB (ZI portion of BMEWS),[9]:{{{3}}} with RCA Display Information Processor (DIP)[24]:{{{3}}}—DIPS displays were also at the Offutt AFB war room floor and balcony,[31] as well as at the Pentagon[12]:{{{3}}}

To predict when parts "might break down",[32]:{{{3}}} the contractor also installed RCA 501 computers [10] with 32k "high speed memory", 5-76KC 556 bpi 3/4" tape drives, & 200 track random access LFE drums.[citation needed] The initially-replaced portions of BMEWS included the Ent CC&DF by the Burroughs 425L Missile Warning System at the Cheyenne Mountain Complex[33] (FOC July 1, 1966.)[12]:{{{3}}} The original Missile Impact Predictors were replaced (IOC on August 31, 1984),[12]:{{{3}}} and BMEWS systems were entirely replaced by 2001 (e.g., radars were replaced with AN/FPS-120 SSPARS) after Satellite Early Warning Systems had been deployed (e.g., 1961 MIDAS, 1968 Project 949, and 1970 DSP satellites).

4 AN/FPS-50 detection reflectors at Thule J-site (replacement by an AN/FPS-120 with "two-faced…phased array radar…in 2QFY87.")[34] The concrete foundation included a large refrigeration system to prevent the curing concrete's heat from melting Permafrost.
The Thule J-site BMEWS station's detection arcs of 200°[35] were a missile warning "fence" created by 4 radars' separate arcs: each AN/FPS-50 created 2 arcs (shown) centered at 3.5° and 7° elevation[5]:{{{3}}} (exaggerated in illustration.) Each arc was created by a smaller radar beam ~1° wide x 3.5° high at a "horizontal sweep rate…fast enough that a missile or satellite cannot pass through…undetected".[5]:{{{3}}} Concerns in 1962 of "ERBM's (Extended Range Ballistic Missiles)" were that missile speeds after burnout would be higher than the initially-deployed Soviet ICBMs[36]:{{{3}}} and prevent the sweeping "Lower Fan" and then the "Upper Fan" (with "revisit time of 2 sec")[37]:{{{3}}} from detecting the missiles. A missile within the lower arc (~1.75-5.25° elevation) would be detected at a "Lower Fan Q Point" (black dot) and then by the upper fan (black dot with jagged outline), which allowed the impact area to be estimated from "where the object crossed the two fans and the elapsed time interval between fan crossings"[5]:{{{3}}} (displays showed the uncertain impact point as an elliptical area.) The free flight range of the missile outside the atmosphere (burnout to reentry) depends on the flight path angle and on the missile's parametric value of Q calculated from altitude and speed—additional ballistic range within the atmosphere to an estimated burst altitude was determined from computerized look-up tables in the Missile Impact Predictor.[5]:{{{3}}}
BMEWS tracking monitors in the Thule Tactical Operations Room, which were upgraded in 1987[38]:{{{3}}} (renamed "Missile Warning Operations Center"[39]).
Fylingdales AN/FPS-49 radomes in 1986 (2 of 3 radars were "constantly swinging back and forth in preset arcs to the east and north, looking 4,800 kilometeres into space, from just above the horizon to nearly straight overhead".)[40] Fylingdales radars were replaced by Raytheon/Cossor AeroSpace and Control Data Corporation, at a cost of US $100M (3-faced phased array antenna and embedded CDC-Cyber computer)[citation needed] and later changed to an Upgraded Early Warning Radar by Boeing Integrated Defense Systems[41] with 3 faces built August 1989-October 1992.[42]

Background

On June 2, 1955, a General Electric AN/FPS-17 "XW-1" radar at Site IX[43] in Turkey that had been expedited was completed by the US in "proximity to the ballistic missile launch test site at Kapustin Yar in the Soviet Union"[4]:{{{3}}} for tracking Soviet rockets[37] and "to demonstrate the feasibility of advanced Doppler processing, high-power system components, and computerized tracking needed for BMEWS [sic]".[4]:{{{3}}} The first missile tracked was on June 15, and the radar's parabolic reflector was replaced in 1958,[43]:{{{3}}} and its range was "extended from 1000 to 2000 nautical miles"[44] after the 1957 Gaither Commission identified that because of expected Soviet ICBM development, there would be "little likelihood of SAC's bombers surviving since there was no way to detect an incoming attack until the first warhead landed".[45] BMEWS' General Operational Requirement 156 was issued on November 7, 1957 (BMEWS was "designed to go with the active portion of the WIZARD system") and on February 4, 1958; the USAF informed Air Defense Command (ADC) that BMEWS was an "all-out program" and the "system has been directed by the President, has the same national priority as the ballistic missile and satellite programs and is being placed on the Department of Defense master urgency list."[46] By July 1958 after NORAD manning began, ADC's 1954 blockhouse for the Ent AFB command center had inadequate floor space; and Ent's "requirement for a ballistic missile defense system display tacility...brought renewed action...for a new command post"[9]:{{{3}}} (the JCS approved the nuclear bunker on February 11, 1959.).

Planning and development

On January 14, 1958, the US announced its "decision to establish a Ballistic Missile Early Warning System"[47]:{{{3}}} with Thule to be operational in 1959—total Thule/Clear costs in a May 1958 estimate were ~$800 million (an October 13, 1958, plan for both estimated completion in September 1960.)[48]:{{{3}}} The Lincoln Laboratory's radar at Millstone Hill, Massachusetts, was built and provided data to a 1958 CG-24 computer for "trajectory estimates", e.g., Cape Canaveral missiles, and an "adjunct high-power UHF test facility employed the Millstone transmitter to stress-test the components that were candidates for the operational BMEWS."[4]:{{{3}}} (A twin of the Millstone Hill radar was dedicated at Saskatchewan's Prince Albert Radar Laboratory on 6 June 1959.)[4]:{{{3}}} A prototype AN/FPS-43 BMEWS radar[5]:{{{3}}} completed at Trinidad in 1958 went operational on February 4, 1959, the date of an Atlas IIB firing from Cape Canaveral Launch Complex 11[11] (lunar reflection was tested January–June 1960.)[12] On June 30, 1958, "NORAD emphasized that the BMEWS could not be considered as a self-contained entity separate from the Nike-Zeus, or vice versa."[49]

On March 18, 1959, the USAF told the BMEWS Project Office[where?] to proceed with an interim facility[50]:{{{3}}}:93 for the "AICBM control center" with an anti-ICBM C3 computer[36]:148 (e.g., for when the USAF Wizard[36]:{{{3}}}:157 and/or Army Nike Zeus[51]:{{{3}}} ABMs became operational), and the basement of the 1954 ADC blockhouse was considered for the interim center.[36]:{{{3}}}:158 A "satellite prediction computer" could be added to the planned missile warning center if Cheyenne Mountain's "hardened COC slipped considerably beyond January 1962"[50]:{{{3}}}:93 (tunneling began in June 1961.) In early 1959 for use at Ent in September 1960, a BMEWS display facility with "austere and economical construction with minimum equipment" was planned in an "annex to the current COC building".[50]:{{{3}}} In late 1959, ARPA opened[where?] the 474L System Program Office,[13] and BMEWS' "12th Missile Warning Squadron at Thule…began operating in January 1960."[52] Following a Nike ABM intercept of a test missile, the planned Cheyenne Mountain mission was expanded in August 1960 to "a hardened center from which CINCNORAD would supervise and direct operations against space attack as well as air attack"[53] (NORAD assumed "operational control of all space assets with the formation of" SPADATS in October 1960.)[45]:{{{3}}} The 1st Aerospace Surveillance and Control Squadron (1st Aero) was activated at Ent AFB on February 14, 1961; and Ent's Federal Building was completed c. 1960-1.

Deployment

Clear AFS construction began in August 1958 [13] with 700 workers[32]:{{{3}}} (completed July 1, 1961),[32] and Thule J-site construction began by May 18, 1960,[54][55] with radar pedestals complete by June 2.[51] Thule testing began on May 16, 1960,[14] IOC was on September 30,[48]:{{{3}}} and the initial operational radar transmission was in October 1960[56]:{{{3}}} (initially duplex vacuum tube IBM 709s occupied 2 floors).[15]

False alarm
On October 5, 1960, when Khrushchev was in New York,[57]:{{{3}}} radar returns during moonrise at Thule[58] produced a false alarm (on January 20, 1961, CINCNORAD approved 2-second FPS-50 frequency hopping to eliminate reception of echoes beyond artificial satellite orbits.)[4]:{{{3}}} On November 24, 1961, an AT&T operator failure at their Black Forest Microwave Station northeast of Colorado Springs[59] caused a BMEWS communications outage to Ent and Offutt (a B-52 near Thule confirmed the site still remained.)[60]

Training for civilian technicians included a February 1961 RCA class in New Jersey for a Tracking Radar Automatic Monitoring class.[61] The "Clear Msl Early Warning Stn, Nenana, AK" was assigned to Hanscom Field, Massachusetts, by the JCA on April 1, 1961.[62]:{{{3}}} By May 16, 1961, Ent's "War Room at NORAD" had a glass map for plotting aircraft and had a "map [that] lights up" to show multiple impact ellipses and times "before the huge missile[s] would burst"[57] (separate from Ent's BMEWS CC&DF building, the 2 story blockhouse had a war room with, left of the main NORAD region display, a BMEWS display map and "threat summary display" with a count of incoming missiles.)[63] The Trinidad Test Site transferred from Rome AFB to Patrick AFB on July 1, 1961 (closed as "Trinidad Air Station" in 1971)[62]:{{{3}}} and the same month, the 1st Aero began using Ent's Space Detection and Tracking System (SPADATS) operation center in building P4's annex[64] (Cheyenne Mtn's Space Defense Center became fully operational in 1967.)[47]:{{{3}}} The BRCS undersea cable was cut "presumably by fishing trawlers" in September, October, and November 1961 (the BMEWS teletype and backup SSB substituted);[30]:{{{3}}} and in December 1961, Capt. Joseph P. Kaufman was charged "with giving [BMEWS] defense data to…East German Communists."[16]

BMEWS surveillance wing

The 71st Surveillance Wing, Ballistic Missile Early Warning System, was activated on 6 December 1961 at Ent AFB (renamed 71st Missile Warning Wing on 1 January 1967, at McGuire AFB July 21, 1969 – April 30, 1971).[62]:{{{3}}} Syracuse's BMEWS Test Facility at GE's High-Power Radar Laboratory[65] became the responsibility of Rome Air Development Center on April 11, 1962[66] (Syracuse's Eagle Hill Test Annex closed in 1970)[62]:{{{3}}} and on July 31, 1962, NORAD recommended a tracking radar station at Cape Clear to close the BMEWS gap with Thule for low-angle missiles (vice those with the 15-65 degree angle for which BMEWS was designed.)[30] By mid-1962, BMEWS "quick fixes" for ECCM had been installed at Fylingdales Moor, Thule and Cape Clear AK[30]:{{{3}}} and by June 30, integration of BMEWS and SPADATS at Ent AFB was completed.[12]:{{{3}}} During the Cuban Missile Crisis, the Moorestown AN/FPS-49 radar on October 24 was "withdrawn from SPADATS and realigned to provide missile surveillance over Cuba."[30]:{{{3}}} 1962 "strikes and walkouts" delayed Fylingdales' planned completion from March until September 1963 and on November 7, the Pentagon BMEWS display subsytem installation was complete.[12]:{{{3}}} At the end of 1962, NORAD was "concerned over BMEWS' virtual inability to detect objects beyond a range of 1500 nautical miles."[30]:{{{3}}} The Moorestown FPS-49 completed a BMEWS "signature analysis program" on scale models by January 1963.[6]

Air Defense Command

Operations transferred from civilian contractors (RCA Government Services)[8]:{{{3}}}:29 to ADC on January 5, 1962[56] (renamed Aerospace Defense Command in 1968.) Fylingdales became operational on September 17, 1963,[17] and Site III transferred to RAF Fighter Command on January 15, 1964[67] (after becoming operational on September 17, 1963.)[56]:{{{3}}} Remaining BMEWS development responsibilities transferred to the "Space Track SPO (496L)" when the BMEWS SPO closed on February 14, 1964[12]:{{{3}}}—e.g., the AN/FPS-92 with "66-inch panels" (hexagonal)[68] was added to Clear in 1966[69] (last of the 5 tracking radars),[70] and in 1967, BMEWS modification testing was complete on May 15, when the system cost totalled $1.259 billion.[12]:{{{3}}} In 1968, Ent's 9th Division HQ had a Spacetrack/BMEWS Maintenance Section.[18]

BMEWS used two types of radars, the UHF range/425 MHz AN/FPS-50, with four (at Site 1) or three (at Site 2) fence antennas for initial detection, each 165 feet (50 m) tall and 400 feet (120 m) wide, and UHF range/425 MHz AN/FPS-49. One fence antenna covered a 40-degree sector of the horizon, for a total site coverage of 120 degrees.[citation needed] The Soviet Union developed[when?] a Fractional Orbital Bombardment System (FOBS) in part to counteract the network of sensors covering the northern hemisphere, including BMEWS, which was only able to point in a fixed direction. FOBS placed a warhead in low earth orbit, reducing the line-of-sight ranges tremendously compared to the traditional lofted trajectories of a conventional ICBM. Additionally, the FOBS could be launched southward, overflying most of the globe and then approaching the U.S. from the south, where it would be invisible to BMEWS. Submarine-launched ballistic missiles also avoided detection by BMEWS, developing into a credible threat in the 1970s. The Defense Support Program (DSP) early warning satellites were developed in part to counter this threat, detecting the infrared "bloom" from the launch rockets no matter where they occurred.[citation needed] In 1975, SECDEF told Congress that Clear would be closed when Cobra Dane and the Beale AFB PAVE PAWS became operational.[19] By 1976, BMEWS included IBM 7094, CDC 6000, and Honeywell 800 computers.[71]

USAF Space Command

On October 1, 1979, Thule and Clear transferred to Strategic Air Command when ADCOM was broken up[72] then to Space Command in 1982. By 1981 Cheyenne Mountain had been averaging 6,700 messages per hour[73] compiled via sensor inputs from BMEWS, the JSS, the 416N SLBM "Detection and Warning System, COBRA DANE, and PARCS as well as SEWS and PAVE PAWS" for transmission to the NCA.[74] To replace AN/FSQ-28 predictors, a late 1970s plan for processing returns from MIRVs [20] installed in new Missile Impact Predictor computers was complete by September 1984.[12]:{{{3}}}[38]

External media
Images
image icon Both Trinidad test radars & 1957 FPS-50 reflector scale model
image icon 1961 Thule sketch, FPS-50 wave guides, & "memory and logic unit"
image icon 1961 BMEWS Rearward communications "billboard type" antenna
image icon construction of a Fylingdale's radome
image icon "Moorestown's Giant Golf Ball
image icon Scan newsletter of Site III
image icon SAC DIP screen with impact ellipses (Reel 2, minute 4:40)
Video
video icon Eyes of the North
video icon Flyingdales Rearward Data Room

References

  1. ↑ Lua error in package.lua at line 80: module 'strict' not found.
    Lua error in package.lua at line 80: module 'strict' not found.
  2. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  3. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Lua error in package.lua at line 80: module 'strict' not found.
  5. ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 Lua error in package.lua at line 80: module 'strict' not found.
  6. ↑ 6.0 6.1 Lua error in package.lua at line 80: module 'strict' not found.
  7. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  8. ↑ 8.0 8.1 8.2 8.3 8.4 Lua error in package.lua at line 80: module 'strict' not found.
  9. ↑ 9.0 9.1 9.2 Preface by Lua error in package.lua at line 80: module 'strict' not found. "NORAD looked at the Zl portion ot the BMEWS not oal.y as an integral portion ot the system, but as the heart ot the entire ballistic m1asUe detense system."
  10. ↑ http://www.ieeeghn.org/wiki/images/b/b5/100_Years_with_IEEE_in_the_Delaware_Valley_1984,_Part_1.pdf
  11. ↑ http://www.loc.gov/pictures/item/ak0486/
  12. ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 Lua error in package.lua at line 80: module 'strict' not found.
  13. ↑ 13.0 13.1 Lua error in package.lua at line 80: module 'strict' not found.
  14. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  15. ↑ http://www2.gwu.edu/~nsarchiv/NSAEBB/NSAEBB43/doc5.pdf
  16. ↑ http://history.defense.gov/resources/1984_DoD_AR.pdf
  17. ↑ https://books.google.com/books?id=cMgdYypcPc8C&pg=PA39&lpg=PA39&dq=spadats+bmews&source=bl&ots=twnQbFj52X&sig=Ri9laEXr5rylCYXuGoK23MUqKSQ&hl=en&sa=X&ei=ML0XU4LZHqPK0wH9iYE4&ved=0CD0Q6AEwBA#v=onepage&q=spadats%20bmews&f=false
  18. ↑ 18.0 18.1 Lua error in package.lua at line 80: module 'strict' not found.
  19. ↑ http://www.radomes.org/museum/equip/fps-50.html
  20. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  21. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  22. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  23. ↑ https://www.esrc.ac.uk/my-esrc/grants/R000238555/outputs/Download/623cc844-6b4d-4d58-a0da-2ef70b6cc202 the USA and UK agreed to be separately responsible for their own rearward data handling systems.’ [46] The UK systems were to meet Air Staff Requirement 2208 and called for ‘display of processed IRBM data at the Air Defence Operations Centre (ADOC), the Bomber Command Operations Centre (BCOC), the Air Ministry Operations Centre and, for standby purposes, at the Air Defence Main Control Centre and Headquarters No. 1 Group. The processed data will also be passed to NORAD over the USA rearward data handling system and this system
  24. ↑ 24.0 24.1 https://books.google.com/books?id=viDGg4_NvPQC&pg=PA342&lpg=PA342&dq=FSQ-28+BMEWS&source=bl&ots=dIDooLZTzK&sig=dAciebESRd7p3_kzdvslDzwOpU0&hl=en&sa=X&ei=678ZU4XZE4TAkQfvlYHQBA&ved=0CEYQ6AEwBQ#v=onepage&q=FSQ-28%20BMEWS&f=false
  25. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  26. ↑ http://www.alternatewars.com/WW3/WW3_Documents/Fortifications/ABMWSP_Summary_23_Apr_1960.htm Progress is satisfactory on the establishment of rearward communications from the forward sites to the Zone of the Interior display facilities at Colorado Springs, Colorado. On 1 December, through communication was established between the switchboard at Thule and the BMEWS Project Office in New York City. This tie line, together with a similar one between Thule and Westover Air Force Base, Massachusetts, represents the first use to be made of the submarine cable completed this last summer between Thule and Cape Dyer.
  27. ↑ http://claytwhitehead.com/ctwlibrary/Box%20018/001_Telecommunications%20(Domestic%20Satellite)%20October-December%201969%20(2%20of%203%20folders).pdf
  28. ↑ Lua error in package.lua at line 80: module 'strict' not found. (see also "DEWDROP Troposheric Scatter AM Communications Link between Thule BMEWS and Cape Dyer")
  29. ↑ http://www.members.shaw.ca/johnbubb/index_files/bmews.htm
  30. ↑ 30.0 30.1 30.2 30.3 30.4 30.5 1962 NORAD/CONAD Historical Summary, July-December
  31. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  32. ↑ 32.0 32.1 32.2 Lua error in package.lua at line 80: module 'strict' not found.
  33. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  34. ↑ https://fas.org/spp/military/program/nssrm/initiatives/clearu.htm)
  35. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  36. ↑ 36.0 36.1 36.2 36.3 Preface by Lua error in package.lua at line 80: module 'strict' not found.
  37. ↑ 37.0 37.1 Lua error in package.lua at line 80: module 'strict' not found.
  38. ↑ 38.0 38.1 http://airforcehistoryindex.org/data/001/073/102.xml
  39. ↑ http://www.globalsecurity.org/space/facility/clear-mwoc.htm
  40. ↑ https://news.google.com/newspapers?nid=1301&dat=19880615&id=q3NWAAAAIBAJ&sjid=WOQDAAAAIBAJ&pg=5477,3917703
  41. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  42. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  43. ↑ 43.0 43.1 Lua error in package.lua at line 80: module 'strict' not found. (also available as Fall 1964 version)
  44. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  45. ↑ 45.0 45.1 Lua error in package.lua at line 80: module 'strict' not found.
  46. ↑ USAF memo to Air Defense Command cited in 1958 NORAD/CONAD Historical Summry, Jan-Jun
  47. ↑ 47.0 47.1 Lua error in package.lua at line 80: module 'strict' not found. (list also at NORAD.mil & in 2008 book
  48. ↑ 48.0 48.1 Lua error in package.lua at line 80: module 'strict' not found.
  49. ↑ Lua error in package.lua at line 80: module 'strict' not found. (cited by 1958 NORAD/CONAD Historical Summary, Jan-Jun)
  50. ↑ 50.0 50.1 50.2 Preface by Lua error in package.lua at line 80: module 'strict' not found.
  51. ↑ 51.0 51.1 Lua error in package.lua at line 80: module 'strict' not found.
  52. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  53. ↑ Lua error in package.lua at line 80: module 'strict' not found. (cited by Schaffel, p. 262)
  54. ↑ https://news.google.com/newspapers?nid=1906&dat=19600518&id=qckfAAAAIBAJ&sjid=tdgEAAAAIBAJ&pg=1035,684283
  55. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  56. ↑ 56.0 56.1 56.2 Lua error in package.lua at line 80: module 'strict' not found.
  57. ↑ 57.0 57.1 Lua error in package.lua at line 80: module 'strict' not found.
  58. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  59. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  60. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  61. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  62. ↑ 62.0 62.1 62.2 62.3 Lua error in package.lua at line 80: module 'strict' not found.
  63. ↑ Lua error in package.lua at line 80: module 'strict' not found. (NOTE: The p. 4 command post photo caption does not identify if it is in the Ent blockhouse (1954-1963) or in the Chidlaw Building, where war room operations moved to the NORAD/CONAD Combined Operations Center in 1963.)
  64. ↑ [full citation needed]1961–1969 Historical reports from the Squadron on file at the Air Force Historical Research Agency, Maxwell AFB AL, AFHRA Microfilm reel KO363
  65. ↑ http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=06432626
  66. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  67. ↑ Lua error in package.lua at line 80: module 'strict' not found.)
  68. ↑ https://news.google.com/newspapers?nid=1955&dat=19620329&id=VJAuAAAAIBAJ&sjid=A5wFAAAAIBAJ&pg=2794,715597
  69. ↑ https://news.google.com/newspapers?nid=2512&dat=19660708&id=ZadIAAAAIBAJ&sjid=NwENAAAAIBAJ&pg=1025,753004
  70. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  71. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  72. ↑ compiled by Lua error in package.lua at line 80: module 'strict' not found.
  73. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  74. ↑ Lua error in package.lua at line 80: module 'strict' not found.
Retrieved from "https://infogalactic.com/w/index.php?title=Ballistic_Missile_Early_Warning_System&oldid=1426669"