Prototype radar track
The first contact came from Gyatt’s AN/SPS-49 (XN-1), then under Operational Test and Evaluation Force trials. The ship held the contact intermittently and photographed its own radar scope.

USS Gyatt’s experimental long-range radar detected an unknown contact north of Puerto Rico. Lieutenant Commander Kyle H. Woodbury was vectored toward it in a Crusader and reported a dark delta-shaped object, roughly fighter-sized, capable of extreme acceleration and climb. The Air Force later called it an unidentified aircraft. CIA analysts then obtained the original radar film, ruled out their own OXCART/YF-12A family, and still could not identify the type or operator.
The first contact came from Gyatt’s AN/SPS-49 (XN-1), then under Operational Test and Evaluation Force trials. The ship held the contact intermittently and photographed its own radar scope.
Lt Cdr Kyle H. Woodbury visually described a dark delta about the size of a fighter, with a single tail light or afterburner-like source appearing during acceleration.
Navy messages, Blue Book routing, nineteen scope-photo prints, the original radar film transfer and later CIA memoranda preserve the investigation chain far better than most 1960s UFO cases.
By November 1964 USS Gyatt was no longer the Terrier-equipped DDG-1 shown in many older photographs. Her missile installation had been removed in 1962, she had reverted to DD-712, and she was being used by the Navy’s Operational Test and Evaluation Force for experimental work.
That matters because the radar itself was unusual: the AN/SPS-49 carried the suffix XN-1, marking an experimental prototype. A radar-scope recording system was installed, which is why the contact produced a rare physical sensor record rather than only operator recollection.
The 19 November intercept began at about 21:12 local time. Woodbury reported clear weather, good visibility and a full moon. The Gyatt was roughly 220 miles northwest of the aircraft and UHF communications were poor at that range, but the ship repeatedly advised him when the contact reappeared.
The initial Navy message reported a track in excess of 3,800 knots. That headline figure became the most famous number in the case — and later the most contested.
SENSOR LAYER · AN/SPS-49 (XN-1) PROTOTYPE · USS GYATT DD-712The destroyer warns Woodbury of the unknown while he is flying over Puerto Rico at about 30,000 feet.
Woodbury reports a black or dark-gray delta, approximately fighter-sized, with no normal navigation lights and a single light source at the tail during acceleration.
The target reportedly slowed and matched the Crusader’s general altitude, heading and speed, taking up a position about eight to nine miles off the pilot’s nine o’clock.
Woodbury turns to close. The object accelerates away in a climbing turn, reportedly passing above 50,000 feet.
During Woodbury’s return toward Roosevelt Roads, the contact reportedly closes again from behind to within several miles before the engagement ends.
Woodbury’s assessment was deliberately narrow: he wrote that there was no reasonable explanation of the target, yet still evaluated it as an aircraft — “very high performance” — because it maneuvered like one. He singled out extreme acceleration, deceleration at will and the steep climb beyond 50,000 feet. That restraint matters more than later UFO wording.
On 3 December 1964 the Norfolk Test and Evaluation Detachment forwarded two enclosures to the Air Force: a detailed chronology and nineteen prints made from the AN/SPS-49 radar presentation. The recording camera existed because the prototype radar was under an evaluation programme.
The evidence chain did not end with those prints. CIA OXCART correspondence from February 1965 says the Navy provided the Agency with the original radar film and accompanying prints so its scientific-intelligence specialists could perform a fresh technical analysis.
That is unusually strong provenance for a historical radar-UFO case: the raw recording was known to exist, was transferred between agencies and was specifically analysed. The modern limitation is that the complete original film/print set is not presently available publicly for independent remeasurement.
RAW SENSOR MATERIAL · ORIGINAL FILM + 19 PRINTS · OFFICIAL CUSTODY DOCUMENTED · PUBLIC ACCESS INCOMPLETEGyatt’s first operational reporting gave the spectacular figure that made the case famous. CIA memoranda later repeated it as the ship’s reported value.
The Foreign Technology Division’s December 1964 scope-photo analysis said the target was subsonic for much of the track, then accelerated without exceeding about 1,515 knots; average speed during the accelerated segment was about 1,200 knots.
CIA’s later analysis of the radar photography reported a good track exceeding 300 nautical miles on a course of about 165° relative to Gyatt, at roughly 485 knots relative speed.
Those are not minor differences. They fundamentally change the case. The 3,800-knot figure is an initial operational estimate, not a secure speed measurement established by later analysis.
The CIA’s February memorandum went further than the Air Force: it concluded that there was no high-altitude ultra-high-speed UFO north of Puerto Rico during the 18–24 November period. Yet it simultaneously said there were apparently valid tracks and/or observations of unidentified aircraft near the Atlantic Fleet Weapons Range on five dates.
So the technical downgrading of the speed does not erase the event. It changes the question from “what flew at impossible speed?” to “what aircraft-like target generated the radar and visual observations, and who operated it?”
TECHNICAL RESOLUTION · INITIAL REPORT ≠ FTD ANALYSIS ≠ CIA SCIENTIFIC RE-ANALYSISMilitary correspondence records apparently valid contacts or observations near the Atlantic Fleet Weapons Range on 16, 17, 18, 19 and 24 November. The events differed in speed, altitude and behavior and should not be collapsed into one recurring “UFO.”
Captain Paul Y. Powell, combat intelligence officer at Ramey AFB, reported that during the November series there had been several IFF Mode 1 paints — but that they were smeared. If those replies came from the same unknown targets, they would strongly favor real transponder-equipped aircraft over an exotic phenomenon.
The limitation is attribution. The surviving message does not cleanly tie every IFF return to Woodbury’s 19 November delta, nor does it preserve a readable identity code. That is why the IFF evidence belongs in the case, but not as a retroactive identification.
The 24 November event was also distinct: CIA briefing notes describe another high-speed, high-altitude target pulling away from a Crusader flying about Mach 0.99 at 45,000 feet. The 18 November contact, by contrast, was low-speed and low-altitude.
FIVE-DAY CLUSTER · DISTINCT EVENTS · IFF EVIDENCE ATTRIBUTION UNCERTAINAfter the Air Force technical finding, the case did not simply disappear. On 8 December 1964 the Air Force Chief of Staff asked Air Defense Command for more information because “high level interest” required details.
By February 1965 the file had entered the CIA’s TOP SECRET BYEMAN/OXCART channel. A Navy cable had circulated a tentative identification of the object as a YF-12A — the Air Force interceptor relative of the CIA A-12. CIA’s Special Activities office explicitly rejected that identification and said it had persuaded the Office of Naval Intelligence that the object was not a YF-12A or similar Lockheed aircraft.
The Navy then supplied CIA with the original radar film and prints. Donald F. Chamberlain’s scientific-intelligence analysis concluded that the 19 November object was probably a delta-wing fighter with significantly better climb performance than the F-8C in the 50,000-foot regime.
The obvious intelligence question was foreign reconnaissance. The Atlantic Fleet Weapons Range was conducting missile activity worth observing, and a Soviet MiG-21 reconnaissance configuration was examined as a possible class of aircraft. But the same memorandum said there was no evidence of MiG-21 reconnaissance activity from Cuba by Soviet or Cuban pilots.
That is the actual endpoint of the intelligence record: not “CIA confirmed a UFO,” and not “CIA identified a MiG.” It is a probable high-performance delta-wing aircraft of unknown type and operator, after a U.S. black-program explanation had been excluded.
CIA SCIENTIFIC INTELLIGENCE · BYEMAN/OXCART · YF-12A EXCLUDED · PROBABLE DELTA-WING AIRCRAFTExcellent on Woodbury’s wording, the five-day sequence, the nineteen prints and chain of command. Its presentation of the CIA technical speed result is less clear than the newly readable D022 analysis.
Correctly separates the original 3,800-knot report from CIA’s later ~485-knot relative-speed result and highlights the original radar-film transfer under OXCART control.
This version keeps the Navy operational estimate, Air Force/FTD technical reading and CIA/OSI re-analysis separate, while still preserving the pilot’s independent visual evidence and the unresolved aircraft identity.
The USS Gyatt case is strongest when stripped of the headline number. A Navy destroyer detected a contact on an experimental air-search radar, a veteran Crusader pilot was vectored toward it, and that pilot visually reported a dark delta-shaped object whose performance exceeded the aircraft he knew.
The famous 3,800-knot figure did not survive technical review. Air Force analysts derived a much lower track; CIA’s later scientific analysis reduced it further to roughly 485 knots relative to Gyatt. That matters. But neither review supplied a type, tail number or operator. The official category narrowed to aircraft without reaching an identity.
That leaves a very Cold War kind of unresolved case: not evidence of a spacecraft, but a sensor-backed military encounter in which the United States appears to have seen an aircraft-like target and still failed to determine who was flying it.