CIA-UAP-D022: The Analysis under BYEMAN Control and Project OXCART, Puerto Rico, February 1965

Source file: CIA-UAP-D022_Unidentified-Flying-Object-Reported-near-Puerto-Rico_1965.pdf Originating agency: Central Intelligence Agency (CIA), Office of Scientific Intelligence (OSI) Document type: Memorandum for the Assistant Director for Special Activities, BYE-3517/65, copy 7 of 8; with action sheet and control sheet Date: 11 February 1965 (incidents: 16 to 24 November 1964) Classification: TOP SECRET, BYEMAN control system, Project OXCART (declassified; Approved for Release 2026) Page count: 6 VIRIN: 260807-O-D0360-1139 PURSUE Release: 5

Summary

This is the CIA's formal analysis of the series of sightings near Puerto Rico in November 1964, written some three months after the events. It takes the form of a memorandum from Donald F. Chamberlain, Assistant Director for Scientific Intelligence, to the Assistant Director for Special Activities, and it refers back to an earlier document, BYE-2081/65 of 1 February 1965, and to three attachments.

The most striking feature of the document is not its content but its security wrapper. It is handled under the BYEMAN control system and restricted to those cleared for Project OXCART, that is, for the CIA's A-12 reconnaissance aircraft program. The implication is simple and important: when a report of a fast unidentified object over the Caribbean came in, one of the first questions asked inside the Agency was whether it was one of the Agency's own aircraft.

The conclusion of the analysis inverts the impression left by the briefing that preceded it: there was no high-altitude, ultra-high-speed UFO north of Puerto Rico in the period under review. But the memorandum does not close the file, because it explicitly confirms that there were apparently valid tracks and observations of unidentified aircraft on five separate dates.

Research Article

The control wrapper: why OXCART

The cover sheet of the file carries the legend "Handle Via Indicated Controls: BYEMAN", and beneath it: "Access to this document will be restricted to those persons cleared for the specific projects", with a large stamp below reading "OXCART". BYEMAN was the control system covering the most highly classified American aerial and space reconnaissance programs, and OXCART was the cover name for the A-12, the reconnaissance aircraft that flew above Mach 3 at altitudes over 80,000 feet.

That context is the key to understanding the document. In 1964 the United States possessed an aircraft capable of generating precisely the radar track under discussion, and very few people knew it existed. Placing the analysis under OXCART control meant that the question "is this ours?" was examined at the only classification level at which it could be examined. The official release summary notes that the AD/SA and the AD/SI ruled out domestic experimental aircraft, including the YF-12A of the OXCART program, as a possible attribution.

The cover sheet also bears a handwritten annotation marking the file's place in the Agency's records, containing the words "UFO's" and a range of years, evidence that the Agency maintained a subject file on the matter.

The first finding: no ultra-fast UFO

The first paragraph of the memorandum is the most consequential: "Detailed analysis of the radar photography of 19 November 1964 and review of associated correspondence indicate that there was, in fact, no high altitude ultra-high-speed UFO north of Puerto Rico during the 16-24 November 1964 period."

This is a direct negation of the central figure in the briefing prepared for Walter Elder, where a track in excess of 3,800 knots was reported. But the remainder of the sentence immediately qualifies it: "There were, however, apparently valid tracks and/or observations of unidentified aircraft in the vicinity of the Atlantic Fleet Weapon Range on 16, 17, 18, 19, and 24 November 1964."

The distinction is precise: what is ruled out is not that unidentified aircraft were observed, but that the object was moving at an impossible speed. In the Agency's terms, the problem moved out of the domain of anomalous phenomena and into the domain of foreign reconnaissance.

What the pilot saw and what the radar showed

The second paragraph presents the raw data from the two sensors. The pilot, identified here as a US Navy F-8C pilot, "was able to distinguish the object as a delta shape about the size of a jet fighter, reported it as having much higher performance, and estimated object speed to be in excess of Mach 3." Alongside that, "The USS Gyatt reported a radar track in excess of 3800 knots."

The first sub-paragraph sets out the examination of the photography: during the incident, radar photographs were taken of the PPI display of the SPS-49 radar. Analysis of the photographs shows a good track over more than 300 nautical miles for the object in question, and that "The object was flying a course of about 165 degrees relative to the Gyatt at a relative speed of about 485 knots."

Here lies the heart of the technical resolution: 485 knots, not 3,800. The gap between those two numbers is the explanation for the entire case. The second sub-paragraph adds the detail that explains why there were photographs at all: "At the time, the AN/SPS-49 radar aboard the Gyatt was undergoing an evaluation test program -- hence, the use of a recording camera."

The significance is twofold. On one hand, because of that test program there exists objective documentation that made later analysis possible. On the other, the fact that the radar was in an evaluation state rather than fully operational offers a possible explanation for the anomalous speed reading obtained in real time.

The conclusion: a delta fighter, not a phenomenon

The third paragraph states the conclusion: "In view of the radar photographs and pilot observation, it is concluded that the so-called UFO on 19 November was probably a delta-wing fighter of a type having a significantly higher climb performance than the F-8C at the 50,000 foot altitude regime."

The wording is measured. There is no positive identification of a type here, only an assessment of likelihood based on what was observed. The qualification follows immediately: "Based on the limited information provided in the associated correspondence, other objects reported during the period of 16 to 24 November would appear to be unidentified aircraft."

In other words: one event was explained, the rest remained open.

The Cuban reconnaissance hypothesis

The fourth paragraph offers the strategic explanation. First the motive: "Apparently, missile test firings were scheduled for the AFWR during this time period, and it is conceivable that the area in question could have been an attractive target for reconnaissance."

Then the geography: "The USS Gyatt was located 325 n.m. from the eastern tip of Cuba during the 19 November incident, well within MiG-21 range." Then the capability: "The USSR has a MiG-21 reconnaissance configuration with AFA-39 aerial camera and possibly SIGINT equipment."

And the concluding sentence, a textbook example of cautious intelligence drafting: "There is no evidence at hand to suggest or deny any MiG-21 reconnaissance activity based in Cuba, either with Soviet or Cuban pilots."

It is worth noting that this hypothesis is not free of difficulties. The MiG-21 in a reconnaissance configuration was not an aircraft with climb performance markedly superior to the F-8C at 50,000 feet, and its planform is not a pure delta either. The memorandum itself does not claim that this is what happened; it sets out the possible framework and admits that there is no evidence either way.

Distribution and Significance

The memorandum was distributed in eight copies only: two to the addressee, two to the Assistant Director for Scientific Intelligence, two to DSD/SI and two to ADB/DSD/SI. Distribution that narrow is characteristic of BYEMAN material.

The importance of the document is chiefly methodological, and it is twofold. First, this is a well-documented case in which an American intelligence agency took a dramatic UFO report, tested it against the objective evidence available, namely the radar scope photography, and found that the most impressive figure in the report did not survive scrutiny. Reading CIA-UAP-D023 and then CIA-UAP-D022 clearly illustrates the gap between real-time reporting and after-the-fact analysis.

Second, and precisely for that reason, the qualification that remains in paragraph 1 and paragraph 3 carries additional weight. The very same analysis that dismissed the 3,800-knot track determined that on five separate dates there were apparently valid tracks and observations of unidentified aircraft, and that the other objects remain unidentified. When a skeptical party arrives at a partial conclusion, the part left open weighs more.

The archive holds further CIA documents from the period, among them Senator Russell's "flying saucer" sighting file of 1955 and the report on the Soviet test range at Sary Shagan, released in earlier releases, and together they present a consistent pattern: the Agency examined such reports primarily through the lens of the technology gap with the Soviet Union.

Key People

Locations

Incidents

Notable Quotes

"Detailed analysis of the radar photography of 19 November 1964 and review of associated correspondence indicate that there was, in fact, no high altitude ultra-high-speed UFO north of Puerto Rico during the 16-24 November 1964 period." -- section 1

"There were, however, apparently valid tracks and/or observations of unidentified aircraft in the vicinity of the Atlantic Fleet Weapon Range on 16, 17, 18, 19, and 24 November 1964." -- section 1

"The US Navy F-8C pilot was able to distinguish the object as a delta shape about the size of a jet fighter, reported it as having much higher performance, and estimated object speed to be in excess of Mach 3." -- section 2

"The object was flying a course of about 165 degrees relative to the Gyatt at a relative speed of about 485 knots." -- section 2a

"At the time, the AN/SPS-49 radar aboard the Gyatt was undergoing an evaluation test program -- hence, the use of a recording camera." -- section 2b

"It is concluded that the so-called UFO on 19 November was probably a delta-wing fighter of a type having a significantly higher climb performance than the F-8C at the 50,000 foot altitude regime." -- section 3

"Based on the limited information provided in the associated correspondence, other objects reported during the period of 16 to 24 November would appear to be unidentified aircraft." -- section 3

"There is no evidence at hand to suggest or deny any MiG-21 reconnaissance activity based in Cuba, either with Soviet or Cuban pilots." -- section 4