Radar over Oak Ridge

What the file holds

The FBI’s file on flying discs, 62-HQ-83894, holds about fifty pages on Oak Ridge, Tennessee, where the Atomic Energy Commission ran its plants: Army messages, FBI memoranda and teletypes, reports of the Army’s Counter Intelligence Corps (CIC) and signed statements. They cover a photograph from July 1947 and a run of radar and visual reports from March 1950 to January 1951. The FBI itself did not investigate; it watched, “in the capacity of an observer” (Section 5, p. 91), and passed on what the Army, the Air Force and the AEC found.

The pin stands on the town of Oak Ridge, because the reports put the object “directly over Oak Ridge”. The sighting of 18 December 1950 was made from the turnpike towards the S-50 Area, about a mile from the White Wing entrance. The documents give no coordinates.

A photograph from July 1947 and a drop of water

A memorandum from the FBI office in Knoxville of 10 January 1949 (Section 4, pp. 84–88) says that “the attached photographs were taken by W. R. PRESLEY in July of 1947”, in front of his house at 218 Illinois Avenue: the first shows “the vapor trail”, the second “the ball of fire”. It records that Colonel C. D. Gasser asked Mr. George Rathman of the AEC’s Security Division to recover the copies in circulation, and that “Mr. RATHMAN advises that he succeeded in rounding up twenty-four copies of these photographs, and that, according to the statements of PRESLEY, no more copies were made or distributed” (p. 84). “It was the opinion of Mr. RATHMAN that the photographs were, without doubt, authentic” (p. 86).

A month later Colonel Gasser forwarded the evaluation from Wright-Patterson Air Force Base (letter of 10 February 1949, pp. 112–113):

“When the negative, containing the sphere, is examined by strong incident light, it is noted that the emulsion is raised at that point above the normal level of the remaining emulsion. This indicates that either a drop of warm water or a drop of developer struck the film at this point and rolled down this negative and the succeeding negative.”

The Knoxville office concluded on 18 February 1949 that the photographs “are the result of accident or purposeful hoax and are not actually photographs of a “flying saucer”” (p. 109). The two prints and a clipping from the Knoxville News-Sentinel are in the release as Serial 153.

An amateur radar in Knoxville

On 2 March 1950 the Third Army reported to the Director of Intelligence (Section 5, p. 57):

“On 1 March at 2135 hours the station picked up an object 340 degrees and 18 miles from Knoxville altitude 40,000 feet. Direction and distance put the object directly over Oak Ridge.”

The station was that of Stuart E. Adcock, “owner and operator of Radio Station WROL, Knoxville”, who “is a radio ham operator and has set up in his home in Knoxville an Army Surplus APN-7 radar set” (p. 80). By our conversion, 340 degrees and 18 miles from Knoxville (35.96°N 83.92°W) gives about 36.20°N 84.03°W, north of Knoxville, not over Oak Ridge. The document does not say from where the bearing was measured.

The documents disagree with one another, and we leave the disagreements as they are:

• The time. The Army has “2135 hours” on 1 March (p. 57); the FBI memorandum of 3 March says Adcock “had called the Knoxville Office at 11:15 P.M. on March 1” (p. 80), and the Director’s letter of 14 March puts the detection itself “at 11:15 p. m.” (p. 86).
• The height. For 2 March the Army has “at 1105 … 335 degrees and 18 miles from Knoxville altitude 40,000 feet” (p. 57); the FBI memorandum has “at 11:15 A.M. on March 2 about 100,000 feet up and about 18 miles from his home” (p. 80).

The Army’s message of 3 March adds that at 21:30 on 2 March the station “picked up 2 objects 310 degrees, altitude 80000 feet … moving in circular motion but in opposite directions”, with a “Density of object similar to DC-3 airplane, speed not established but report as “terrific”” (p. 70).

“Not verified”: who checked what

On 6 March 1950 the FBI in Knoxville wired the Director (p. 84):

“EXISTENCE OF OBJECT REPORTED BY ADCOCK AS BEING DIRECTLY OVER OAK RIDGE AT ONE HUNDRED THOUSAND FEET ALTITUDE NOT VERIFIED. ADCOCK REPUTEDLY CAPABLE RADIO TECHNICIAN. ADCOCK CLAIMS TO HAVE DETECTED OBJECT WITH HIS RADAR EQUIPMENT ON FIVE OCCASIONS OVER THREE DAYS. NAVAL RESERVE RADAR EQUIPMENT AT KNOXVILLE DID NOT DETECT OBJECT ON ANY OCCASION, BUT TECHNICIANS STATE IT IS NOT CONSIDERED EFFICIENT FOR AIRCRAFT AT EXTREME ALTITUDES.”

The Knoxville office’s report, of which pages 2 to 7 are in the release (pp. 91–96), sets out the checks:

• 2 March, evening. Special Agent E. L. Seagraves of the CIC and Special Agent W. M. Price of the OSI, neither with radar experience, watched Adcock’s screen and saw “some “pips” which, according to ADCOCK, indicated an object with the same general elevation and azimuth”; “they were unable to make any authoritative statement … but they had seen sufficient to give them reason to believe it warranted investigation” (p. 91).
• 3 March, morning. The Naval Reserve’s radar on Alcoa Highway was run in continuous search, and “no object whatsoever could be detected”, while Adcock was reporting the object (p. 92).
• 3 March, afternoon. Colonel Gasser: “while it was highly improbable that aircraft could sustain flight at an altitude of 100,000 feet, it was absolutely possible from a scientific and engineering standpoint” (p. 93).
• 3 March, evening. Captain Robert Cross, “a radar expert”, sat at Adcock’s set: “No object was reported by ADCOCK during this evening.” He “had very grave doubts as to the capabilities of the surplus APN-7 radar set”, but had had no opportunity to see it at work (p. 94).
• 4 to 6 March. Gasser and Cross found the equipment “haphazard at best”; checking Adcock’s readings of known aircraft, they “found him to be off to a considerable extent regarding speed, elevation and azimuth”. From 6 to 8 March Adcock “could not be located” (pp. 94–95).

The report sums up: “the actual existence of an object at such an exceptional altitude is quite improbable and no explanation is yet known as to just what was detected by ADCOCK on his screen or, in fact, whether anything was detected” (p. 95). On 9 March the Army reported that the “radar operator inexperienced and radar set has been modified so as to cast doubt on reliability of reading” (p. 88).

Eleven echoes in October

On 13 October 1950 the Knoxville office wired the Director (Section 6, p. 92):

“USAF RADAR INSTALLATION AT KNOXVILLE AT ELEVEN TWENTYFIVE PM, EST, OCTOBER TWELVE, PICKED UP INDICATIONS OF ELEVEN OBJECTS AND PERHAPS MORE TRAVELING ACROSS CONTROLLED AREA OF ATOMIC ENERGY INSTALLATION AT OAK RIDGE.”

Heights of 1,000 to 5,000 feet, speeds of 100 to 125 miles an hour. A fighter “REPORTED NO OBJECT COULD BE SEEN EITHER VISUALLY OR ON PLANES RADAR SCREEN”, and the AEC patrol saw nothing. The teletype ends: “NO REASONABLE EXPLANATION FOR RADAR READINGS YET DEVELOPED ALTHOUGH OPERATORS ARE EXPERIENCED RELIABLE PERSONNEL AND RADAR SET IS IN PERFECT OPERATING CONDITION.” A letter of 4 November forwards CIC reports on further detections on 20, 23, 24 and 26 October (p. 96); the reports themselves are not in the release.

“Radar jamming”

On 5 December 1950 the Director wired Knoxville (Section 6, p. 93):

“REURTEL DECEMBER FOUR LAST REGARDING POSSIBLE RADAR JAMMING AT OAK RIDGE. ARRANGEMENTS SHOULD BE MADE TO OBTAIN ALL FACTS CONCERNING POSSIBLE RADAR JAMMING BY IONIZATION OF PARTICLES IN ATMOSPHERE. CONDUCT APPROPRIATE INVESTIGATION TO DETERMINE WHETHER INCIDENT OCCURRING NORTHEAST OF OLIVER SPRINGS, TENNESSEE, COULD HAVE HAD ANY CONNECTION WITH ALLEGED RADAR JAMMING.”

Neither the Knoxville teletype of 4 December it answers, nor any account of the incident near Oliver Springs, nor any answer to the order is in the release.

A light over the turnpike, 18 December 1950

Two groups on their way to work saw a light that morning, and each wrote a statement.

The first, signed by John R. Hood, Jr., Lt. Col. USAF, Edward W. Hribar, Commander USN, and Walter L. Carss, Jr., Major USAF (Section 6, p. 103), says they “were riding to their work at NEPA Division, Fairchild Engine and Airplane Corp., in the S-50 Area at Oak Ridge” with three others, and that “At approximately 0827, while riding southwest on the turnpike just outside the restricted area”, Hood, Carss and Hribar saw it; the other three did not:

“The object appeared only as the bright reflection of the sun from an apparently metal surface, much as might be expected from an aircraft at a great distance. No accurate estimate of the objects size or range could be made from the observation. It appeared to be west-southwest of Oak Ridge Townsite at an angle of elevation of about 25 degrees from the level.”

The second, a letter from Gene A. Goedjen of NEPA dated 28 December 1950 (pp. 104–105), names Dr. A. J. Miller, Dr. V. P. Calkins, Mr. J. Frank Coneybear, Mr. A. O. Mooneyham and Mr. F. T. Bly, riding “between 0820 and 0830 … approximately one mile short of the “Y” cutoff to White Wing entrance and Y-12”. All but Dr. Calkins saw “a light emanating in the shape of a circle, of an intensity much greater than that of a bright moon”, 15 to 30 degrees above the horizon between west and north-west, shrinking over about thirty seconds until it was “somewhat similar to a large star”. “The observers were unable to estimate approximate size, speed, or vertical elevation.” The letter’s subject line gives the date as “December 19, 1950”; its text gives 18 December.

By our calculation, at 08:27 local time on 18 December 1950 the sun stood about 7 degrees above the horizon at Oak Ridge, at an azimuth of about 126 degrees, in the south-east. The light was in the west: the sun was behind the watchers. That is all the calculation shows.

The CIC’s summary quotes the log of the Air Force radar at McGhee Tyson for the same morning: “0832 hours - Atomic Energy Commission reported aircraft over Northeast end of area - no paint”, “0839 hours - Small paint near Southeast corner of area on 190 degree”, “0845 hours - Lost contact. Fighter interception was attempted with negative results” (pp. 101–102).

A smoke cloud and a star

The CIC’s summaries of 20 January 1951 add three more entries (Section 6, pp. 106–110):

• 14 December. “A group of targets blanketed the Radar Scopes in the area directly over the government Atomic Energy Commission projects at Oak Ridge”; a fighter intercept “met with negative results”. Photographs of the screen were taken, and the targets “can readily identified from the permanent radar echos by comparing the photographs” (p. 107). The summary’s first paragraph dates the event “14 December 1951”, its second “14 December 1950”.
• 20 December. “Small paint in area (Oak Ridge Controlled Area). Very, very slow. Made perfect intercept (with F-82 Fighter aircraft) and orbit surrounding small smoke cloud.” (p. 106)
• 16 January 1951. Two bright objects; through a spotting scope one of them “took on many peculiar forms … thus generally fitting the description of all “flying saucers” ever described to him”, in the words of Captain Clevenger. From the radar log: “AF 7177 sighted subject object and reported it to be a star”, and “Oak Ridge Patrol Headquarters reports that observed object determined (to be a star)” (pp. 106, 108). The page carrying the log is headed “20 January 1950”; the others are dated 1951.

“An impressive lack of any agency”

The Knoxville report of March 1950 ends with a judgement on the handling, not on the object (Section 5, p. 96):

“there nevertheless seemed to be an impressive lack of any agency actually taking the responsibility for the situation and taking any action to verify or disprove the threat.”

It adds that “it is now felt that this entire matter was in a manner of speaking “dry run”“. The AEC said it had “neither the facilities nor the equipment” to defend itself, and the Army, the Air Force and the FBI each acted as observers. The report also notes that “It was erroneously reported that a CIA technician would come to Oak Ridge” (p. 93).

What the file does not contain

In the released parts of the file we found none of these:

• the first page of the Knoxville report of March 1950, and with it its author;
• anything recorded by Adcock’s set itself;
• the CIC reports on 20 to 26 October 1950;
• the Knoxville teletype of 4 December 1950 on radar jamming, and any account of the incident near Oliver Springs;
• any answer to the Director’s order of 5 December;
• the photographs of the radar screen of 14 December;
• Colonel Gasser’s letters to Wright Field about the handling in March.

Why this scores where it does

Witnesses score 3: officers and engineers named in statements signed within ten days, but a sighting of seconds from a moving car, which half of each carload did not see. Radar scores 2: an Air Force radar “in perfect operating condition” in October and the McGhee Tyson log, but Adcock’s set was unreliable, and no return was confirmed by a fighter or a second radar. Optics scores 0: the only photographs, from 1947, were a drop on the negative, and the screen photographs of December are not in the release. Physical trace scores 0.

Multi-channel scores 2: on 18 December two carloads and a radar return, but the return came after the sighting and in another part of the area; in March a single channel, Adcock’s set. Documentation scores 4: records of those days with times, names and radar logs, though with the disagreements set out above and with pages missing. Anomaly scores 2: 100,000 feet from an unreliable set; the rest resolves into a star, a reflection or echoes that nothing else saw. Data today scores 2: the file is public, but the logs, the screen photographs and the CIC reports are outside the release.

That puts the case at 1.8 overall, class D, with the status insufficient data.

What would settle it

The CIC reports on October 1950 and the Air Force radar logs for 12 October: the one report whose operators and set were called reliable.

The photographs of the radar screen of 14 December 1950, which the summary says identify the targets.

The Knoxville teletype of 4 December 1950 and whatever answered the order on radar jamming.

The first page of the Knoxville report of March 1950.