Thule Site J

Last updated
Thule Site J
Thule BMEWS.jpg
Thule AN/FPS-50 detection reflectors (1959–1987)--concrete foundations included a large refrigeration system to prevent the curing concrete's heat from melting Permafrost.[ citation needed ]
Thule Site J
General information
Typeradar structures
Location10 miles from Thule AB (13 road miles)
Coordinates 76°34′13″N68°17′56″W / 76.570258°N 68.298998°W / 76.570258; -68.298998 Coordinates: 76°34′13″N68°17′56″W / 76.570258°N 68.298998°W / 76.570258; -68.298998   Early Warning Radar 76°34′04″N68°17′03″W / 76.56785°N 68.284214°W / 76.56785; -68.284214 AN/FPS-49A bldg [2]
Opened1958-60 (AN/FPS-50)
1963 (AN/FPS-49A)
1987 (AN/FPS-120)

Thule Site J (J-Site) is a United States Air Force (USAF) radar station in Greenland near Thule Air Base for missile warning and spacecraft tracking. The northernmost station of the Solid State Phased Array Radar System, the military installation was built as the 1st site of the RCA 474L Ballistic Missile Early Warning System and had 5 of 12 BMEWS radars. The station has the following structures:


BMEWS tracking monitors in the Thule Tactical Operations Room BMEWS Tac Ops Room.jpg
BMEWS tracking monitors in the Thule Tactical Operations Room


PAVE PAWS (blue) and BMEWS (red) sites and coverage PAVE PAWS&BMEWS.svg
PAVE PAWS (blue) and BMEWS (red) sites and coverage

BMEWS General Operational Requirement 156 was issued on November 7, 1957 (BMEWS had originally been "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 was "...being placed on the Department of Defense master urgency list." [8] On January 14, 1958, the US announced its "decision to establish a Ballistic Missile Early Warning System" [9] with Thule to be operational in 1959—total Thule and Clear Air Force Station costs in a May 1958 estimate were ~$800 million (an October 13, 1958, plan for both estimated completion in September 1960.) [10]

A World War II ship (freighter) operated by the Burns & Roe company [11] originally provided the Site J electrical and heating supplies until a powerplant was constructed years later, [12] and water was from Thule AB via a branch to the site. [13]


Kiewit was contracted for heavy construction (e.g., the AN/FPS-50 reflector foundations [14] and tunnels between transmitter buildings), [15] and construction began in May 1958 [16] (a trial reflector installation failed due to ordinary carbon steel bolts instead of 1.5% chrome steel.) [15] The maintenance building with electric heat was the first building complete; and the four AN/FPS-50 reflectors with 25-ton foundations were complete by August 8, 1959 [15] ("two pedestals for trackers" were built for deferred radars.) [17] After the July 13, 1959, treaty No. 5045 with Canada regarding intermediate sites, the Western Electric BMEWS Rearward Communications System (BRCS) was established between the "switchboard[ where? ] at Thule and the BMEWS Project Office in New York City"—a similar line between Thule and Massachusetts used a summer 1959 "submarine cable... between Thule and Cape Dyer" [18] ("BMEWS Rearward Long-Lines System" [19] stations were at CFS Resolution Island [20] & CFS Saglek.) [21] President Dwight D. Eisenhower was notified on April 23, 1960 of "construction work at Thule on schedule [and that] all technical buildings have been accepted and emplacement of the electronic components is underway [and] erection of the four radar antennas was completed", [22] and radar testing began on May 16, 1960 [23] —a simplex vacuum tube IBM 709 used as the prototype Missile Impact Predictor (MIP) occupied 2 floors (duplex IBM-709-TX solid-state computers of the AN/FSQ-28 Missile Impact Predictor Set were later installed in Building 2.) [24] To predict when parts "might break down", [25] the contractor also installed a "Checkout Data Processor"--RCA 501 computers with 32k "high speed memory", 5-76KC 556 bpi 3/4" tape drives, & 200 track random access LFE drums.[ citation needed ] The initial radar transmission from one of the scanner buildings was in August 1960.

RCA operations

On the same date as the BMEWS Central Computer and Display Facility in the continental United States, "at midnight on 30 September 1960 ["BMEWS Site I"] achieved initial operational capability", and a "shakedown" period followed which used the simplex MIP and voice transmission of data to the Colorado Springs' CC&DF. [26]

False alarms
On October 5, 1960, when Nikita Khrushchev, the Soviet Premier, was in New York, [27] radar returns during Thule moonrise [28] produced a false alarm (on January 20, 1961, CINCNORAD approved 2-second FPS-50 frequency hoping to eliminate reception of echoes beyond artificial satellite orbits.) [29] On November 24, 1961, an AT&T operator error at their Black Forest Microwave Station northeast of Colorado Springs [30] caused a BMEWS communications outage to the Ent AFB CC&DF and its output to Strategic Air Command (a nearby B-52's overflight confirmed Site J had not been attacked.) [31]

The BRCS undersea cable from Greenland had been cut "presumably by fishing trawlers" in September, October, and November 1961 (the BMEWS teletype and backup SSB substituted) [32] --Hard Head missions for continual monitoring commenced in 1961 (the Bomb Alarm System had been installed at the Thule and Clear BMEWS sites by 10 February 1961. [10] After local interference (e.g., "cranes and floor waxers") and equipment problems were mitigated and a 72-hour test verified "the automatic rearward data transmission" (BRCS), the 1961 "authorization to begin fully automatic operation; effective 2400 hours GMT 31 January, was issued" [26] "Lt. Col. Harry J. Wills [was the] senior air force officer on the project at Thule" on January 3, 1961 [33] ("BMEWS deputy program director" by 1964—he was reassigned from the BMEWS SPO to the "Space Track SPO" on February 14, 1964.) [34]

Air Defense Command

Thule operations transferred from civilian contractors (RCA Government Services) [35] to Air Defense Command on January 5, 1962; [36] and 1962 sinkholes formed in the drainage ditch at "Scanner 6". By mid-1962, BMEWS "quick fixes" for ECCM had been installed for Thule "to recognize when it was being jammed." [32]

An RCA AN/FPS-49A Radar Set with specialized radome for Thule weather [37] was installed by December 1963, [38] and Thule multipath testing was completed by May 1964. [39] In 1967 when the system cost totalled $1.259 billion, BMEWS modification testing ended on May 15 ("completion of the BMEWS"); [34] and the Bomb Alarm System caused a false alarm during the 1968 Thule Air Base B-52 crash (the system was deactivated in 1970.) [10] In June 1980, Thule's FPS-49A radome by Goodyear [11] "burnt to the ground" and was rebuilt, and a late 1960s satellite communications terminal was moved from the Thule P-Mountain site to Site J in 1983. [40] To replace AN/FSQ-28 predictors, a late 1970s plan for processing returns from MIRVs [41] installed new Missile Impact Predictor computers and was complete by September 1984. [34] [42] After being contracted for Thule on July 29, 1983; construction of an AN/FPS-120 Early Warning Radar was started on November 7, 1984, the "array plate" was complete on June 26, 1985, and the 1st satellite track was on June 8, 1986. [34]

Solid State Phased Array Radar

External media
Searchtool.svg site construction
Searchtool.svg 1961 Thule sketch, FPS-50 wave guides, & "memory and logic unit"
Searchtool.svg 1961 BMEWS Rearward communications "billboard type" antenna
Nuvola apps kaboodle.svg Eyes of the North

Thule's BMEWS radars were deactivated in June 1987. [43] [44] The BMEWS system at Thule had been "replaced" [45] by the SSPARS AN/FPS-120 with "two-faced…phased array radar [completed] in 2QFY87" (January–March). [46] with 240 degree detection arc [47] The AN/FPS-49A was intact and in disrepair in 1996, [16] and the antenna and radome were removed by 2014. After the Danish parliament approved, Raytheon was contracted in 2005 to upgrade Thule's "Early Warning Radar" as part of the larger Ground-Based Midcourse Defense program. [3] Intended to be ready in 2008, the installation was actually completed on June 24, 2009. Thule's AN/FPS-132 Upgraded Early Warning Radar (UEWR) completes about 10% of the United States' observations of Earth orbiting satellites. [48]

Related Research Articles

PAVE PAWS early warning radar

PAVE PAWS is an elaborate Cold War early warning radar and computer system developed in 1980 to "detect and characterize a sea-launched ballistic missile attack against the United States". With the first solid-state phased array deployed, the system at the perimeter of the contiguous United States used a pair of Raytheon AN/FPS-115 radar sets at each site as part of the United States Space Surveillance Network. One system was sold to Taiwan and is still in service with that island nation.

Ballistic Missile Early Warning System

The RCA 474L Ballistic Missile Early Warning System was a United States Air Force Cold War early warning radar, computer, and communications system, for ballistic missile detection. The network of twelve radars, which was constructed beginning in 1958 and became operational in 1961, was built to detect a "mass ballistic missile attack launched on northern approaches [for] 15 to 25 minutes' warning time" also provided Project Space Track satellite data.

Thule Air Base US air base in Greenland

Thule Air Base, or Thule Air Base/Pituffik Airport, is the United States Air Force's northernmost base, located 1,207 km (750 mi) north of the Arctic Circle and 1,524 km (947 mi) from the North Pole on the northwest coast of the island of Greenland.

RAF Fylingdales Royal Air Force base in Yorkshire, England

Royal Air Force Fylingdales or more simply RAF Fylingdales is a Royal Air Force station on Snod Hill in the North York Moors, England. Its motto is "Vigilamus". It is a radar base and is also part of the Ballistic Missile Early Warning System (BMEWS). As part of intelligence-sharing arrangements between the United States and United Kingdom, data collected at RAF Fylingdales are shared between the two countries. Its primary purpose is to give the British and US governments warning of an impending ballistic missile attack. A secondary role is the detection and tracking of orbiting objects; Fylingdales is part of the United States Space Surveillance Network. As well as its early-warning and space-tracking roles, Fylingdales has a third function - the Satellite Warning Service for the UK. It keeps track of spy satellites used by other countries, so that secret activities in the UK can be carried out when they are not overhead. The armed services, defence manufacturers and research organisations, including universities, take advantage of this facility.

Clear Air Force Station

Clear Air Force Station is a United States Air Force Station radar station for detecting incoming ICBMs and submarine-launched ballistic missiles to NORAD's command center and to provide Space Surveillance data to Air Force Space Command's Space Control Center (SCC). Clear's AN/FPS-123 Upgraded Early Warning Radar is part of the Solid State Phased Array Radar System (SSPARS) which also includes those at Beale AFB, Cape Cod AFS, RAF Fylingdales and Thule Site J. The "historic property" was one of the Alaska World War II Army Airfields and later a Cold War BMEWS site providing NORAD data to Colorado's BMEWS Central Computer and Display Facility (CC&DF).

Cobra Dane

The AN/FPS-108 COBRA DANE is a PESA phased array radar installation operated by Raytheon for the United States Air Force at Eareckson Air Station on the island of Shemya, Aleutian Islands, Alaska. This radar system was built in 1976 and brought on-line in 1977 for the primary mission of gathering intelligence about Russia's ICBM program in support of verification of the SALT II arms limitation treaty. Its single face 29 m (95 ft) diameter phased array radar antenna 52.7373°N 174.0914°E faces the Kamchatka Peninsula and Russia's Kura Test Range. COBRA DANE operates in the 1215–1400 MHz band.

Aerospace Defense Command 1946-1980 United States Air Force major command responsible for air defense of the United States

Aerospace Defense Command was a major command of the United States Air Force, responsible for continental air defense. It was activated in 1968 and disbanded in 1980. Its predecessor, Air Defense Command, was established in 1946, briefly inactivated in 1950, reactivated in 1951, and then redesignated Aerospace rather than Air in 1968. Its mission was to provide air defense of the Continental United States (CONUS). It directly controlled all active measures, and was tasked to coordinate all passive means of air defense.

Ground Equipment Facility J-33

Ground Equipment Facility J-33 was a Federal Aviation Administration (FAA) radar station of the Joint Surveillance System's Western Air Defense Sector (WADS) with an Air Route Surveillance Radar (ARSR-4). The facility was previously a USAF general surveillance radar station during the Cold War.

12th Space Warning Squadron

The 12th Space Warning Squadron is a United States Air Force ground-based radar used for missile warning, missile defense, and space situation awareness, stationed at Thule Air Base, Greenland.

4683d Air Defense Wing

The 4683d Air Defense Wing is a discontinued United States Air Force (USAF) organization. Its last assignment was with Aerospace Defense Command (ADC)'s Goose Air Defense Sector at Thule Air Base, Greenland, where it was discontinued in 1965.

Ground Equipment Facility QRC

Ground Equipment Facility QRC is an FAA radar station that was part of a Cold War SAGE radar station for aircraft control and warning "from Massachusetts to southern Virginia, and as far out to sea as possible." Benton AFS was also the first operational "regional data processing center" for the GE 477L Nuclear Detection and Reporting System.

North Atlantic Radio System system

The North Atlantic Radio System (NARS) was a chain of 5 tropospheric scatter communication sites. It was an expansion of the former Distant Early Warning Line. NARS has been built for the United States Air Force (USAF) by Western Electric (AT&T) and its sites were maintained under contract by ITT Federal Electric Corporation. All NARS stations were supervised and controlled by the USAF, by agreement with the Canadian and Danish Governments.

Havre Air Force Station

Havre Air Force Station is a Formerly Used Defense Site that was used as a Cold War general surveillance radar station. In addition to radar facilities and a NORAD Control Center the site had support services: NCO club, bowling alley, hobby shops, library, movie theater, barber shop, exchange, commissary, grade school, and housing for officers and senior NCOs.

213th Space Warning Squadron

The 213th Space Warning Squadron of the Alaska Air National Guard provides early warning of Intercontinental ballistic missiles and Submarine-launched ballistic missiles to the Missile Correlation Center of North American Aerospace Defense Command. The squadron is a geographically separated unit assigned to the 168th Wing at Eielson Air Force Base.

Solid State Phased Array Radar System

The Solid State Phased Array Radar System is a USAF radar, computer, and communications system for missile warning and space surveillance "at five (5) geographically separated units worldwide including Beale AFB, CA, Cape Cod, AFS, MA, Clear AFS, AK, RAF Fylingdales, UK, and Thule AB, Greenland." SSPARS completed replacement of the RCA 474L Ballistic Missile Early Warning System when the last SSPAR was operational at Clear in 2001, the year SSPARS equipment included:

AN/FPQ-16 PARCS phased-array radar system located in North Dakota, United States

The AN/FPQ-16 Perimeter Acquisition Radar Attack Characterization System is a powerful phased-array radar system located in North Dakota. It is the second most powerful phased array radar system in the US Air Force's fleet of missile warning and space surveillance systems.

Falling Leaves was the improvised ballistic missile early warning system during the 1962 Cuban Missile Crisis that networked 3 existing CONUS radars—2 Space Detection and Tracking System (SPADATS) radars and an Aircraft Control and Warning general surveillance radar which was modified by Sperry Corporation to 1,500 mi (2,400 km) range, allowing detection in space near Cuba. The "Cuban Missile Early Warning System (CMEWS)" radars were "realigned" to monitor for nuclear missile launches from the new Soviet launch sites after Soviet R-12 Dvina IRBMs arrived on September 8, intelligence sources in Cuba had reported lengthy missiles transported through towns, and three R-12 sites were photographed by Lockheed U-2s by October 19.

The National Military Command System (NMCS) was the federal government of the United States' Cold War command and control system that consisted of the National Military Command Center (NMCC) at The Pentagon, the Alternate National Military Command Center (NMCC) at Pennsylvania Raven Rock Mountain, 3 National Emergency Airborne Command Post (NEACP) aircraft on 24-hour ground alert, 2 National Emergency Command Post Afloat (NECPA) ships, "and interconnecting communications".

Missile Warning Center

The Missile Warning Center (MWC) is a center that provides missile warning and defense for United States Space Command's Combined Force Space Component Command, incorporating both space-based and terrestrial sensors. The MWC is located at Cheyenne Mountain Air Force Station.

Eglin AFB Site C-6

Eglin AFB Site C-6 is an Air Force Space Command radar station which houses the AN/FPS-85 phased array radar, associated computer processing system(s), and radar control equipment. Commencing operations in 1969, the AN/FPS-85 was the first large phased array radar. The entire radar/computer system is located at a receiver/transmitter building and is supported by the site's power plant, fire station, 2 water wells, and other infrastructure for the system. As part of the US Air Force's Space Surveillance Network its mission is to detect and track spacecraft and other manmade objects in Earth orbit for "the Joint Space Operations Center satellite catalogue". With a peak radiated power of 32 megawatts the Air Force claims it is the most powerful radar in the world, and can track a basketball-sized object up to 22,000 nautical miles from Earth.


  1. "Missile Sites". Retrieved 2015-05-18.
  2. 1 2 "Google Maps". Google Maps.
  3. 1 2 Upgrade to the Thule Air Base Early Warning Radar Site (FBO webpage) (Report). October 8, 2005. Retrieved 2014-03-19.
  4. "The Center for Land Use Interpretation". Retrieved 2015-05-18.
  5. "Thule J Site".
  6. "The Milwaukee Journal - Google News Archive Search" . Retrieved 2015-05-18.
  7. "Broken Arrow -- The B-52 Accident.................. - Thuleforum". Archived from the original on 2015-05-19. Retrieved 2015-05-18.
  8. USAF memo to Air Defense Command cited in 1958 NORAD/CONAD Historical Summary, Jan–Jun
  9. "NORAD Selected Chronology". Federation of American Scientists. Retrieved 2014-03-05. 14 Jan 58 -- United States announced decision to establish a Ballistic Missile Early Warning System (list also at Archived 2012-09-15 at the Wayback Machine & in 2008 book
  10. 1 2 3 Wainstein, L. (June 1975). The Evolution of U.S. Strategic Command and Control and Warning: Part One (1945-1953) (PDF) (Report). Study S-467. Institute for Defense Analyses. pp. 1–138. Retrieved 2014-03-09.
  11. 1 2 "news article title tbd". January 5, 1961. Retrieved 2014-03-17. Sylvania Electric Products for the data take-off unit and the missile impact predictor, and Goodyear Aircraft for the tracking radar antenna, pedestal and domes. Thule power ship was "Hull No. 2150, Froeming Bros Inc., Milwaukee, 1945…built as a 5,000 ton freighter, 338 feet long, 50 broad and 21 deep. … 34,500 kilowatt steam generating plant. The floating power plant performed emergency service after hurricanes in Florida and Puerto Rico before its sides were sprayed with four inches of insulation and it was towed to Thule [for] most of the electricity [and it] feeds three miles of steam heating lines as well. …earth embankment [for] its private lagoon … roller brackets…welded to the side…run on steel pilings driven into the bottom of the bay. … A private contractor, Burns & Roe, Inc., of New York, runs the ship for RCA.
  12. "Yahoo! Groups". Retrieved 2015-05-18.
  13. Desktop Corrosion Control Study for Thule Afr Base, Greenland (Report). Retrieved 2014-03-17. Chlorinated water is piped 10 miles to the distribution storage tanks the [Thule Tracking Station] base. … The water distribution branch that goes to the J-Site (BMEWS)
  14. "Kiewit :: Cold War Construction". Retrieved 2015-05-18.
  15. 1 2 3 "BMEWS Site 1, Under Construction - 1958-1960". Retrieved 2015-05-18.
  16. 1 2 Hoffecker, Whorton, & Buechler. Cold War Historic Properties of the 21st Space Wing (Report). Retrieved 2014-03-20. ADC assumed control ofThule [AB] in 1960 ... The original radar screens were dismantled in 1987 when the site was upgraded to phased-array radar. The scanner buildings and tracking radar remain intact but are not used and have fallen into disrepair. ... Cavalier AS...approximately 67 miles north of Grand Forks, and 15 miles south of the Canada–US border, near the community of Concrete. The 278-acre installation... In 1977, the operation of the PAR Site was transferred to the Air Force ADC... After the elimination of ADC in 1979, PARCS was transferred to SAC. In 1983, the site became a part of AFSPC (and was officially redesignated Cavalier AS). The land at Cavalier is leased from the Army. ...Missile Site Radar (MSR) at Grand ForksCS1 maint: multiple names: authors list (link)
  17. Rogers, Warren Jr. (June 2, 1960). "Summit Failure Speeds Up Development of BMEWS". Herald Tribune News Service. Retrieved 2014-03-09.
  18. "ABMWSP Summary - 23 April 1960". Retrieved 2015-05-18.
  19. "Telecommunications (Domestic Satellite) (2 of 3 folders)" (PDF). October–December 1969. Retrieved 2015-05-18.
  20. Mitchell, Walt. "Memories of Troposcatter at Resolution Island". Archived from the original on 2014-03-11. Retrieved 2014-03-09. the BMEWS Rearward link came from Thule to Dye to ResX1 to ResX on Resolution and then on to Goose Bay. I suspect that was the link maintained by Canadian Marconi under contract in the 1961 to 1974 period. (see also "DEWDROP Tropospheric Scatter AM Communications Link between Thule BMEWS and Cape Dyer ")
  21. "BMEWS". Archived from the original on 2010-10-05. Retrieved 2015-05-18.
  22. Report No. 8, Progress of Anti-Ballistic Missile Weapon System Program (Summary) (Summary with Deputy Secretary of Defense cover letter) (Report). available at Eisenhower Presidential Library . Retrieved 2014-03-21.
  23. "The Spokesman-Review - Google News Archive Search" . Retrieved 2015-05-18.
  24. "Yahoo! Groups". Retrieved 2015-05-18.
  25. "Watchful eye of BMEWS turns toward Soviets" (Google news archive). Ellensburg Daily Record. June 18, 1961. Retrieved 2014-03-09.
  26. 1 2 North American Air Defense Command Historical Summary (Report).[ specify ]
  27. Pearson, Drew (May 16, 1961). "A Day In The War Room At NORAD" (Google news archive). The Palm Beach Post. Retrieved 2014-03-09.
  28. Sampson, Curt (2010-01-25). "The Moon as a Soviet Missile Attack" . Retrieved 2014-03-05.
  29. Stone & Banner. Radars for the Detection and Tracking of Ballistic Missiles, Satellites, and Planets (PDF) (Report). Retrieved 2020-06-11. The Millstone radar served as a development model for RCA's AN/FPS-49, AN/FPS-49A, and AN/FPS-92 radars, all of which were used in the BMEWS. … Millstone was used to develop a fundamental understanding of several important environmental challenges facing the BMEWS. These challenges included the measurement of UHF propagation effects in the ionosphere, the impact of refraction close to the horizon, the effect of Faraday rotation on polarization, and the impact of backscatter from meteors and the aurora on the detection performance of the radar and its false-alarm rate [15–17]. … In the early 1960s, the Millstone radar was converted from a UHF to an L-band system. …the Air Force in the 1960s sponsored the development of Haystack, a versatile facility in Tyngsboro, Massachusetts, that supports radar- and radio-astronomy research and the national need for deep-space surveillance.
  30. "AT&T caused NORAD blackout…" (web post of newspaper column). EVER WONDER?. Colorado Springs Gazette. 2011-08-26. Retrieved 2014-03-10. an engineer we'll call "Q" didn't follow instructions "for routining a TD2 transmitter and receiver." He enclosed diagrams showing what went wrong. There was no "500A termination on the Channel Dropping Network when he was running the Radio Frequency (RF) Sweep Generator to adjust the equipment." That generator leaked RF into the Channel Separating Filter "interfering with all the other transmitters in the Black Forest Microwave Station, causing a complete failure of all channels going to Ent. SAC scrambled all aircraft. Later SAC billed AT&T for all the fuel used."
  31. Philips, Alan F. "20 Mishaps That Might Have Started Accidental Nuclear War". Retrieved 2014-03-05.
  32. 1 2 North American Air Defense Command Historical Summary (Report).[ specify ] " CONAD Control Center (Thule AB, Greenland) ... During Desk Top V, an operational evaluation of the Combat Operations Center was conducted. ... At the start of the Cuban crisis, a Soviet trawler was sighted directly over the [BMEWS undersea] cable. ... BMEWS rearward communications could be substantially affected only by the simultaneous cutting of all cables."
  33. "The Milwaukee Journal - Google News Archive Search" . Retrieved 2015-05-18.
  34. 1 2 3 4 Del Papa, Dr. E. Michael; Warner, Mary P (October 1987). A Historical Chronology of the Electronic Systems Division 1947-1986 (PDF) (Report). Retrieved 2014-03-08. 7 November [1984] Installation of [SSPARS] radar hardware at Site I, Thule, Greenland, for the Ballistic Missile Early Warning System (BMEWS) was begun.
  35. Shore, Bruce (Spring 1963). "the fourth state of matter". Electronics Age. RCA: 29.
  36. "Ballistic Warning Is Aim of BMEWS" (Google news archive). The Evening News. Newburgh, New York. June 19, 1964. Retrieved 2014-03-09. high-speed scanning switches and a massive array of feedhorns… Federal Electric Corp., Paramus, N.J., is the prime contractor for manning and maintaining the Thule BMEWS site.
  37. "AN/FPS-49, 49A" . Retrieved 2014-03-05. The prototype unit operated at Moorestown, New Jersey
  38. "Annual Report of the Secretary of Defense, The Armed Forces, pp. 14-15 ("Continental Air Defense" section)". Department of Defense Annual Report, FY 1960 ( excerpt) (Report). Retrieved 2014-03-06.
  39. Wall, R. B. Test Plan for BMEWS Multipath Tests at Thule Air Base Greenland for 496 System Project Office, TM-4001, The MITRE Corp., May 1964
  40. "Newcomer's Welcome Package: Thule Air Base, Greenland: Home of the 821st Air Base Group" (PDF). Retrieved 2015-05-18.
  41. Robert C. Aldridge (1983). First Strike!: The Pentagon's Strategy for Nuclear War. South End Press. p. 197. ISBN   9780896081543.
  42. "Document Detail for IRISNUM= 01073102". Retrieved 2015-05-18.
  43. Trip Report[s]… (abstract regarding a collection of trip reports) (Report). "VOL I OF II". 1987. IRIS 01098592. Retrieved 2014-03-19.
  44. "12th Space Warning Squadron" . Retrieved 2014-03-19. The radar beam is electronically steered to a programmed location. This process, accomplished in milliseconds, increases capabilities and decreases response time. Each radar face provides 120 degrees azimuth coverage, for a total of 240 degrees coverage. The antenna is inclined +20 degrees for scan coverage of +3.5 to +85 degrees elevation. Each array face contains 3,589 antenna elements; 2,560 are active and 1,029 are inactive.
  45. Duke, S.; Stockholm International Peace Research Institute (1989). United States Military Forces and Installations in Europe. Oxford University Press. p. 47. ISBN   9780198291329 . Retrieved 2015-05-18.
  46. "Clear Upgrade (U)". Archived from the original on 2008-10-11. Retrieved 2015-05-18.
  47. Hanley, Charles J--Associated Press (August 17, 1987). "Soviets, Eskimos protest Thule radar" (Google news archive). Star-News. Retrieved 2014-03-09. The radar, a Phased Array Warning System…can "see" 3,200 miles, 200 miles farther than the old system, and has a 240-degree arc…40 degrees more than the old.