1st Aerospace Control Squadron
The 1st Aerospace Surveillance and Control Squadron, a unit of the USAF Air Defense Command, was activated on 6 February 1961, organized on 14 February 1961,[1] and became operational on 1 July 1961[2] as the SPACETRACK[3]:38 component of NORAD Space Detection and Tracking System (SPADATS). It was the operational version of research and development Project Space Track. Effective 1 October 1961, the Squadron was assigned to the 9th Aerospace Defense Division, which had been activated on 15 July 1961.[4]
The Squadron name was changed to 1st Aerospace Control Squadron on 1 July 1962, but it was still informally called just 1st Aero. The unit was inactivated on 21 April 1976.
Until April 1966, when operations were moved to the NORAD Cheyenne Mountain Complex, 1st Aero was located on the bottom two floors of Ent AFB building P4 Annex, a former hospital building, adjacent to the NORAD command center. [5] The Space Defense Command's 1st Aerospace Control Squadron moved from Ent AFB to Cheyenne Mountain in April 1966.[6]
Contents
Mission
1st Aero was responsible for tracking all artificial earth satellites, space probes, carrier rockets, and debris, US and foreign. The mission included detecting additional objects previously unknown and maintaining a complete catalogue.
The mission is now performed by the 614th Air & Space Operations Center, part of the Joint Space Operations Center at Vandenberg AFB, California. An important additional mission is forecasting possible collisions in space.
Awards
Supporting unit, 4608th Support Squadron, ADC, 1 February 1960 – 30 April 1962[7]
Air Force Outstanding Unit Award, 1 June 1961 – 15 September 1963[1]
Outstanding Air Defense Unit of the Air Defense Command, Air Force Association, September 1963[8]
Air Force Outstanding Unit Award, 1 July 1973 – 30 June 1974[1]
Official Emblem[9]
The 1st Aero emblem was approved on 6 February 1962.
Description
On an Air Force blue rectangular area a stylized computer above a semicircular geometrical pattern all surmounted by a stylized satellite, its four antennae saltirewise, all Air Force golden yellow; the satellite charged with an Air Force blue star; issuing from dexter chief a portion of the sun in splendor, and in sinister chief a formation of stars, Air Force golden yellow.
Motto
On an Air Force golden yellow scroll, edged and inscribed Air Force blue, PRIMARII AETHERIS DEFENSORES, Space Defenders of the First Rank.
Significance
The emblem is symbolic of the squadron and its mission. Against a background resembling in shape the fan-like radar of the Ballistic Missile Early Warning System, deep blue in color to represent the sky, and supplemented with the sun and stars to indicate day and night operations, a stylized satellite of the Vanguard class symbolizes the squadron as the Vanguard of Aerospace Defense. The satellite surmounts two symbols representing a computer for analyses and computations and a detection system with the capability of the MIDAS system and world-wide sensors. The solitary star on the satellite indicates that this is the first organization of this type.
Unofficial emblem
In 1961, 1st Aero had a competition to select the squadron emblem, with ideas to be posted on the bulletin board. One anonymous suggestion, surreptitiously posted in the middle of the night, proved so popular that Colonel Miller, the Squadron Commander, had copies made for all squadron members and other people who supported the squadron.
Here is the text posted with the submission:
Blazoning (Symbology)
Central in our noble emblem is a crystal ball, rampant on a field of confusion, depicted floating in a sea of coffee.
The yellow streak, or batton sinister (heraldic mark of illegitimation, commonly called the bastards' barr) maintains balance between the traditional ADC Azure (Shade 84)[the official color of USAF uniforms] and NORAD purpure [NORAD was sometimes considered purple, the staff being a combination of Army red and Air Force and Navy blue]. Unfortunately, this line of demarcation is not quite long enough to keep things from getting confused. [This is a reference to the ongoing tension between NORAD and ADC, at times even involving CINCNORAD General Lawrence S. Kuter, and the ADC Commander, Lt Gen Robert M. Lee; both sometimes appearing distinctly unfriendly.]
Emblazoned, dexter chief and sinister base, are the symbols of the accuracy within which we attempt to maintain our orbital ephemerides [plus and minus infinity].
Beneath the shield, the heroic name of our noble organization will be forever proclaimed on a roll of six-ply carbon paper.
The crest, above the shield, is a crying towel, presented with the compliments of the 496L SPO [the SPO responsible for the development of Project Space Track]. It is supported by two wings, depicting the hopeful thought that, if things get too tough, you can always go fly.
Sensors
1st Aero had essentially the same set of sensors used by Project Space Track, described in detail in that article, with the addition of two additional Baker-Nunn cameras, one of which was used by the Royal Canadian Air Force at Cold Lake, Alberta, Canada. In March 1961, the Laredo sensor was transferred from the Air Research and Development Command to the Air Defense Command. It was designated Detachment 1, 1st Aerospace Surveillance and Control Squadron, on 1 July 1961, Major Lloyd C. Hill, Commander.[10] In January 1968, the System 440L Over-the-Horizon radar became initially operational.[5] In 1968, SPACETRACK was also supported by the Royal Radar Establishment, Great Malvern, Worcestershire, England.[5] By mid-1969, three USAF Baker-Nunn cameras were operated in support of SPACETRACK under the 18th Surveillance Squadron at Edwards AFB CA (Jupiter, Florida; Johnston Island, central Pacific; and Mt. John, New Zealand) despite serious questions in 1968 about their on-going utility in view of increasing radar tracking accuracies.[11] An FPS-85 phased array radar became operational at Eglin AFB, Florida, in May 1970.
Orbital computations
1st Aero used the methods of orbital prediction developed by Dr. Eberhart W. Wahl at Project Space Track in 1957, which computed ephemerides based on standard Keplerian orbits. This excellent technique became less and less useful as a satellite got lower into the atmosphere, encountering drag, which made it difficult to forecast the ephemeris of the satellite accurately. Because of this, in 1959, Lt Cotter at Space Track had the questionable pleasure of being the first person to lose track of an artificial earth satellite, Explorer IV, for which he was the Department of Defense orbital analyst. The Smithsonian Astrophysical Observatory lost it a day or two later and only Mr. Arthur S. Leonard, of the Sacramento Moonwatch Team, was able to continue tracking somewhat longer, using his own special observational methods.[12]:3
By 1962, the situation was somewhat better. The Soviet satellite Sputnik 4 was slowly entering lower orbits because of the atmospheric drag. Using a new program, Satellite General Perturbations Differential Corrections (SGPDC), and observations from the Shemya radar, 2d Lt Vander Stucken, the orbital analyst for the decay, plotted the changing orbital period and was able to predict the exact revolution on which the satellite reentered. A 20-pound piece of it landed on a street in downtown Manitowoc, Wisconsin on the western shore of Lake Michigan.
Not all 1st Aero satellite tracking was done by looking at computer printouts. In January 1964, 1st Lt Ivan Thomas was the DOA for the launch of Echo 2 (1964-04A). He alerted his co-workers to go to the third-floor balcony of the 1st Aero building and said "Look up – NOW" so they could watch the satellite pass overhead.[13]
To make progress in automating ephemeris forecasts, Aeronutronic and TRW developed sophisticated new programs. 1st Aero orbital analysts evaluated the two programs:
Lt Vander Stucken (now 1st Lt) studied the Aeronutronic submission, Spiral Decay, designed by Geoff Hilton and programmed and validated by Patricia Crossin. Dr. Louis G. Walters was the Manager and Systems Engineer. Spiral Decay was funded to support the USAF space program, which had been experiencing trouble with satellites, such as incorrect orientation at propulsion events, some of which reentered carrying sensitive equipment. It was desired to know more accurately where the reentry would occur in case salvage was possible.[14]
Captains Craig and Strub and Lt Clark worked with Aeronutronic on the project. Detailed astrodynamics reports of this and other Aeronutronic support of Project Space Track and 1st Aero are on file at the offices of Lockheed Martin (formerly Loral Corporation) in Colorado Springs, Colorado. An index of the reports is at the National Museum of the Air Force.[15]
Lt Clark studied the TRW submission, Electronic Systems Precision Orbit Determination (ESPOD). ESPOD had been developed for Program 437 to enable computation of trajectories for satellite intercept.
As a demonstration of the effectiveness of Spiral Decay, the program was used to forecast the reentry of Soviet Cosmos 23 (1963-050A) on Good Friday 1964. Public media had been alerted to the impending decay and many people in Canada saw the fiery reentry. One racetrack even dimmed the lights to enhance the show.
Spiral Decay was considered a more sophisticated program than ESPOD and it used much less computer time to attain more accurate results. It was selected as the 1st Aero standard for analysis, significantly helping predict future decay trajectories. It was also adopted as the primary computer capability for weapon engagement and was very useful in more precisely locating sensors, such at the radar at Diyarbakır, Turkey.[14]
On 1 March 1965, the rocket body of Cosmos 61 exploded between revolutions 1 and 2, giving 1st Aero another challenge to catalog the many fragments. Because the orbital period was 106 minutes, the fragments would not decay quickly. Special techniques were needed to overcome the extensive manual operations needed in the 1961 breakup of the Transit 4A carrier rocket. Two computer programs, SPACESWEEP and ALTEC, the latter written for the IBM 1620 computer by the Special Projects Division, aided automation of the task [but, when Cosmos 200 broke up on 23 January 1968, the breakup created severe problems to the Space Defense Center because of the amount of manual work needed].[11]
Also in March 1965, the Special Projects Division was supporting evaluation of the upgraded Shemya radar and the associated computer, in a project nicknamed BLUE FOX. .BLUE FOX used Spiral Decay and ESPOD to determine the accuracy of the new Shemya system, tracking satellites Transit 2A and ANNA 1B, an SAFSP satellite, since declassified. The BLUE FOX results, showing radar range biases of 129 meters or less, proved that the Shemya FPS-80M was now the most accurate tracking radar in the system.[11]
Another major progress was increasing automation of the correlation of observations with known satellites.
Some problems that developed required effort by 1st Aero personnel to overcome: for example, contractors' software sometimes used different values for important mathematical constants, making the orbital computation results different, depending on which program was used. 1st Lt Rodney M. Larson played an important role in these efforts.
1st Aero orbital elements, along with those computed by the Smithsonian Astrophysical Observatory and the NASA Goddard Space Flight Center, were included in the Satellite Situation Reports regularly published by Goddard. The element sets were passed in a standardized two-line format (which Lt Katz enjoyed referring to as "elephant sets."[16])
In 1963 and 1964, Dr. Wackernagel presented two short courses in celestial mechanics to officers newly assigned to 1st Aero. These assignments replaced some of the original squadron complement who were being reassigned or left the service.[17] `
Operations
In April 1961 a Philco 2000 computer had been installed in Building P4 Annex at Ent AFB for dedicated 1st Aero use. The Phlco 2000 was considered the fastest computer in the world at the time of installation.[18]:1 1st Aero still used IBM punch cards for data, as did Project Space Track. The Philco 2000 was infamous for devouring the cards. The computer was programmed using FORTRAN for batch processing and the TAC assembly language for other work.[19] However, Orbital Analysts still had Friden Square Root Calculators on their desks, a necessary tool.
Project Space Track at Laurence G. Hanscom Field MA was the backup facility for 1st Aero operations. About 49 hours before 1st Aero became operational, the Navy's Transit 4A carrier rocket exploded. Orbital analysts at 1st Aero and at the Hanscom backup achieved a landmark in satellite tracking by identifying 296 of the fragments. Details of this event and the subsequent development of tools for analysis of breakups are at Project Space Track.
From 25 March to 6 April 1962, the 1st Aero orbital computations were transferred to Project Space Track while the Ent AFB computer was being modified.
Effective 5 June 1962, several 1st Aero officers were reassigned to L.G. Hanscom Field to activate the SPACETRACK Center Alternate Facility (SCAF) as a backup for the Colorado Springs center.[11]
In mid-1962, the NORAD DCS/Intelligence (J-2) expressed his appreciation to 1st Aero for the information and expert technical assistance provided in support of NORAD analysis of the Soviet VOSTOK III and VOSTOK IV operations.[20]
In the third quarter of calendar 1962, 1st Aero's operations center was renamed SPACETRACK Operations Center instead of the former SPADAT Operations Center.[11]
In the third quarter of calendar 1963, the 1st Aero organization was changed to include a Central Computer & Display Facility (CC&DF) separate from the SPACETRACK Center.[11] By this time, the SPACETRACK Center had six Divisions: Operations, Space Object Identification, Analysis, Research, Programming, and Intelligence.[11]
In early November 1963, 1st Lt Phillips R. Granberry was the orbital analyst for a new Soviet launch, which had occurred on 1 November. In plotting the observations made by the BMEWS radar at Flylingdales Moor, England, and other sensors he noticed that the data showed an apparent change in the satellite's orbital period. Puzzled, he showed his data to Capt Frederick C. Eaton, who realized that the Soviets had boosted the satellite, changing the orbit. The two officers alerted the NORAD Space Intelligence Division, which passed the information to the intelligence community, where it was received with much interest. This confirmed a boast by Soviet Premier Khruschev that the Russians had a maneuverable satellite, something that had been treated with some disbelief.[21]
It is now known that the satellite, called Polyot, was in fact a prototype orbital carrier rocket for an antisatellite system. Only one other Polyot was launched (in April 1964); the system never became operational.
In mid-1965, there was concern that two Soviet satellites had attempted a rendezvous in space. Thanks to a seemingly overnight miracle, Ralph Schinnerer of Aeronutronic combined the existing XROADS and GROUNDTRACK programs into a new program that could compare the relative positions of two satellites. This enabled the Duty Orbital Analyst to prove that a rendezvous had not taken place. [In fact, Ralph had been developing the program while at Hanscom Field in support of Project Space Track but it had not previously been available for use. He called his program COMBO, which was appropriate, but later gave it the formal name, Computation of Miss Between Orbits.]
COMBO, with some modifications, continues to be a major program in the Space Track arsenal at Vandenberg AFB, as it enables forecasts of possible collisions in space, a major concern for all satellite programs, manned and unmanned.
One major improvement in operations was the creation of a new career field, Space Object Identification Analyst (DSOIA)(AFSC 2025B). This was made possible by some improvement in radar imaging, still primitive, but enabling better assessment of which objects were satellite payloads, which carrier rockets, and which debris. The DSOIAs exchanged information with the NORAD Space Intelligence Division. Intelligence information about the mission of foreign satellites was also primitive. Public announcements by launching agencies and comparison with past launches were both useful. At one point in time, DSOIA duties were also performed by officers at remote sites, including Diyarbakır, Turkey. By the early 1970s, the work was consolidated at Colorado Springs, so that DSOIAs did not have to have remote duty tours.[22] In later years, special telescopes were deployed to assist in identification.[23]
In 1966, although he was not formally a DSOIA, Ralph Schinnerer achieved an interesting object identification: The Gemini IV astronauts saw what appeared to be a nearby space object. Ralph used the COMBO program, but it did not identify any nearby satellites. Shortly thereafter, he was furnished a short movie clip of the mystery object taken by the astronauts. Analysing its motion, he determined that it was probably something associated with the spacecraft, perhaps dangling from a tether.[24]
1st Aero personnel supported the NORAD exhibit in the United States Pavilion at the New York World's Fair in 1964.[25]
Operational details
1st Aero operations were based on the techniques developed at Project Space Track. By 1962,[26] initial observations were processed by the Report Association Program (RASSN) which ran automatically twice a day plus twice for BMEWS data. The program associated observations with known orbits. The output of the program, plus data from the Checker Program (SRCHEK), was sent to the Duty Space Surveillance Officer and Technician (DSSO/DSST) for review with some assistance from the Duty Orbital Analyst (DOA) as needed.
After the daily RASSN runs had been checked, one element correction run was made using the Satellite General Perturbations Differential Corrections (SGPDC) program. This automation was a definite improvement on the manual data plotting done at Project Space Track in 1960.[27] In those days, the DOA would plot data points showing the difference in the time the satellite crossed the equator versus the current ephemeris prediction (on the ordinate) against the time of observation (on the abscissa). He would manually sketch a line as a best estimate of the fit to the data and choose a few points on either side of the line. He then filled out a form with these data points. The form was used to input the data at the IBM 709 computer (earlier the IBM 610), which ran a least squares fit and produced improved orbital elements.
None of this manual procedure was normally necessary by 1962 and the DSSO was able to handle the operation and produce the necessary Bulletin and Look Angles, which sent ephemerides to sensors and other interested parties (bulletin and look angle details at Project Space Track). Information from the latest Bulletins for unclassified satellites (now over 200) was posted on the Satellite Situation Board in the DSSO/DSST area.
About 600 to 800 observations remained unassociated daily. The unassociated observations were passed to the DOA for consideration. Many of these observations in 1962 were of the several hundred pieces from the explosion of the carrier rocket of 1961 Omicron in June 1961, not all yet in known orbits.
If the DOA thought the uncorrelated observations were from pieces associated with a known satellite, he could run the REDUCTION program with the elements of the known satellite and plot the resulting information to distinguish the remaining pieces. So manual plotting was still an important operation for the DOA.
Other special DOA activity occurred when a satellite neared decay. When the orbital period fell below 90 minutes, the DSSO notified the DOA and a special analyst was normally assigned to monitor the decay. In the unusual case of the decay of a Discoverer recovery vehicle that had not come down where programmed, the DOA had access to a special computer program, GRNTRK, which provided a sub-satellite trace for one revolution, to assist in specifying the track.
New friendly launches were handled by a DOA dedicated to the task but, in the case of new Soviet launches, an Analyst for Intelligence was assigned. There were two of these in 1962 (Lt Eric B. Nelson and Lt Gordon E. Markham).
Around 1970, two TSgts, experienced Space Surveillance Technicians, were selected to be Orbital Analysts. They performed very well but, not having college education, they did not get into the astrodynamic details and, not being officers, they could not be awarded AFSC 2025.[16]
Analysis of interplanetary and lunar probe launches were handled by Special Project Analysts, who had several special astrodynamic programs to assist in computations. The Encke program (MUNENDC) was used when the vehicle was within 125 earth radii and the Interplanetary program (IPPD), adjusting for planetary perturbations, for vehicles beyond that distance. The Special Project Analysts also handled special requests for such things as very accurate orbital elements or decay information for a satellite (as might be required by research or educational groups). These analysts also monitored incoming technical papers, attended technical meetings to obtain information which was of use to the mission, and monitored improvements in decay forecasts. Special Project Analysts included Maj Cassidy, Capt Craig, and Lts Clark, Larson, and Rivero.
Personnel
The first Commander of the operational squadron was Col Robert Miller, of Albion, Illinois, former Commander of the 94th Fighter Interceptor Squadron.[1] Colonel Miller retired in August 1965.
The initial cadre of the squadron, trained at Project Space Track in Massachusetts, was:[28][29]
Lt Col William H. Gibson (primary duty Director, SPADATS[30])
Lt Col Dalton F. Newton (primary duty Chief, SPADATS Operations Division, also Director, Spacetrack Center and later Director, SPADATS)[31][32]
Maj James L. Rynning (Administrative Officer[33])
Capt William P. Bingham (primary duty Space Surveillance Officer[30])
Capt Frederick Carl Eaton
Capt Orville L. Greynolds
Capt James W. Head
Capt Billy M. Jackson
Capt Thomas C. Marsters (primary duty Chief, SPADATS Control Center[30])
Capt Donald D. McComb
1st Lt Eric B. Nelson (primary duty Analyst for Intelligence,[30] the first officer in that duty assignment). As such, Lt Nelson was responsible for computing the orbits of all new Soviet launches and for liaison with the Space Intelligence Division, NORAD J-2, located on the top two floors of the same building.
SMSgt Harold E. Barton
For lists of other known 1st Aero personnel (1961–1972) see the talk page of this article.
References
Except as noted, all documents referenced are in the archives of the National Museum of the United States Air Force, Wright-Patterson AFB, Ohio.
- ↑ 1.0 1.1 1.2 1.3 AFSPC/HO. Memorandum, "1st Aerospace Control Squadron". Ent AFB CO: 30 October 2006
- ↑ Miller, [Robert]. Signed draft AF Form 77a. [Ent AFB CO]: 31 August 1961
- ↑ Headquarters USAF. The History of Air Defense Command, Jan – Jun 1964. Showing the official usage as all caps SPACETRACK. Washington DC: 19665?
- ↑ Headquarters Air Defesne Command Special Orders G-69, 19 July 1961
- ↑ 5.0 5.1 5.2 1961–1969 Historical reports from the Squadron on file at the Air Force Historical Research Agency, Maxwell AFB AL, AFHRA Microfilm reel KO363
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Miller, Robert. 1 Aerospace Control Squadron (ADC) letter to Capt Eric B. Nelson. Ent AFB CO: 23 August 1963
- ↑ Miller, Robert. 1 Aerospace Control Squadron (ADC) letter to Capt Eric B. Nelson. Ent AFB CO: 14 August 1963
- ↑ [Department of Defense]. Emblem approval 166185 USAF – K-12986. [Washington DC:] 6 February 1962
- ↑ Air Defense Command. Historical Record of the 1st Aerospace Surveillance and Control Squadron for the period ending 30 June 1961. [Ent AFB CO: 1961]
- ↑ 11.0 11.1 11.2 11.3 11.4 11.5 11.6 1969 Historical reports from the Squadron and its Detachments on file at the Air Force Historical Research Agency, Maxwell AFB AL, AFHRA Microfilm reels KO363 and KO364. From 30 June 1964 to 30 June 1970, twelve 1st Aero historical reports are missing and there are none after that. There are also no 1st Aero Detachment historical reports after 30 June 1970.
- ↑ Cotter, Lawrence R.. Reminiscences About Space Track History. Privately published. [Berkeley CA]: 20 November 2006.
- ↑ Clark, John B. E-mail correspondence. [Colorado Springs CO:] 11 January 2011 and USAF biography Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 14.0 14.1 Walters, Dr. Louis G.. Historical Perspective, Ford/Philco/Loral Aerospace Astrodynamics Role in Space Command Evolution. Zephyr Cove NV: 15 August 1993 in Mansfield, Roger L. et al.(q.v.)
- ↑ [Mansfield, Roger L. et al.]. Index/History for the Aeronutronic Astrodynamics Collection. Loral Corporation. Colorado Springs CO: September 1993
- ↑ 16.0 16.1 Schwartz, Daniel O.. E-mail communications. [Highlands Ranch CO]: 8 November 2010
- ↑ Miller, Terry D.. E-mail correspondence. [Colorado Springs CO]: 7 November 2010
- ↑ Philco Western Region Public Relations Office. "'Asynchronous' Design Concept Permits Heretofore Unobtained Computer Speeds." Philco News Release (S-6). Palo Alto CA: 7 July 1961
- ↑ Mansfield, Roger L.. NOTES ON NORAD'S DELTA SYSTEM, THE SCC, AND SPADOC. [Colorado Springs CO]: 5 November 2010
- ↑ Hull, Harris B.. Headquarters North American Air Defense Command. Letter of Appreciation to Commander, USAF Air Defense Command. Ent AFB CO: 29 August 1962
- ↑ Donaldson, E.M.. "Russian Satellite Seen to Change Orbit," Daily Telegraph. London: 28 November 1963
- ↑ Minear, Leslie H.. Jr.. E-mail correspondence. [Aledo TX:] 25 January 2011
- ↑ Rodriguez, Mary. Kirtland AFB NM: 16 June 2010 "New Focus on Space Object Identification". Archived 15 March 2012 at the Wayback Machine
- ↑ Schinnerer, Ralph. E-mail correspondence, 20 February 2011
- ↑ Newton, Dorr E., Jr.. Memorandum for All Personnel Assigned to NORAD Exhibit. North American Air Defense Command. Ent AFB CO: [May? 1964]
- ↑ Ferguson, Mary E.. TASK SPECIFICATIONS OF THE SPADATS DUTY ORBITAL ANALYST (DOA). Field Note FN=CN-101/000/00. System Development Corporation. Santa Monica CA: 17 September 1962
- ↑ Fitzpatrick, F.M. And Findley, G.B.. The Tracking Operation at the National Space Surveillance Control Center (NSSCC), Eglin AFB, FL: 2 September 1960.
- ↑ Headquarters Air Defense Command. Special Orders Number AAH-56. Ent AFB CO: 6 March 1961
- ↑ Headquarters 4600th Air Base Wing (ADC) and Ent Air Force Base. Special Orders Number P-216. Ent AFB CO: 13 April 1961
- ↑ 30.0 30.1 30.2 30.3 Headquarters 4600th Air Base Wing (ADC) and Ent Air Force Base. Special Orders Number P-379. Ent AFB CO: 6 June 1961
- ↑ Headquarters 4600th Air Base Wing (ADC) and Ent Air Force Base. Special Orders Number P-7. Ent AFB CO: 19 February 1962
- ↑ NORAD 1OOP-S. AF Form 626. Travel Orders. [Ent AFB CO]: 26 June 1962
- ↑ 1st Aerospace Surveillance and Control Squadron. AF Form 626. Travel Orders. [Ent AFB CO]: 20 April 1962
