Nogales, ArizonaDecember 1954

On the morning of December 24, 1954, an F-86D pilot was flying a routine combat air patrol near Nogales, Arizona when he spotted something unusual. At approximately 0519Z (5:19 a.m.), he reported seeing an unidentified object at his eleven o'clock position, roughly 10 to 20 nautical miles northeast of Nogales and about 5,000 to 10,000 feet above him. What he saw looked like a hazy glow of red and green flashes, with a stronger red flash occurring roughly every third pulse.

The pilot quickly locked his radar onto the object when it moved over Nogales, acquiring a strong radar blip. The lock lasted only about five seconds before he lost contact. Despite three separate chase attempts over the next 40 minutes, he could not close the distance. The object stayed 5 to 10,000 feet above him throughout the encounter, maintaining roughly 20 nautical miles distance. It appeared to maneuver deliberately to avoid interception and finally disappeared heading south toward Mexico.

Ground radar operators at Davis-Monthan Air Force Base near Tucson noted momentary interference on their scopes during the second intercept attempt. This interference resembled high voltage power surges. The pilot also reported seeing interference on his scope while manually controlling his radar. The investigators checked all known air traffic in the region. Several military flights were confirmed, but none matched the description of what the pilot encountered. Civil aviation records showed two American Airlines flights and a returning B-47 bomber in the general area, but none fit the timeline or behavior reported.

The Air Force's analysis noted that the pilot may have briefly acquired a genuine radar contact before the object moved beyond his search range. However, they could not confirm whether he had locked onto an actual radar return or ground clutter (radar reflections bouncing off terrain). The radar interference on both the pilot's scope and the ground station could have been coincidental electrical noise rather than caused by the object itself. The investigators also considered that the pilot's visual sighting might have been astronomical, specifically the bright star Canopus at 50 degrees elevation, though they offered no firm conclusion on this point. The final assessment emphasized the "obvious weakness of present detection and interception capabilities along the southern U.S. border" and raised the possibility that an unauthorized aircraft from Mexico had penetrated American airspace, though the evidence for this remained speculative.

The full case file is reproduced below as held by the National Archives, spanning 15 pages of microfilm.