Panama Canal Zone, March 1958March 1958

During March 1958, radar operators in the Panama Canal Zone tracked several unidentified objects over the course of a few days. The sightings sparked significant investigation and debate among military personnel about what the objects might have been.

On the night of March 9 to 10, radar operators at Flamenco Island detected two objects hovering near Fort Kobbe, approximately one hundred yards apart. The radar showed the objects could climb from two thousand feet to ten thousand feet in five to ten seconds, a rate of ascent that caused the tracking radar to lose lock on the targets. Personnel at the radar site reported seeing red and green lights for a brief time, though visibility was good. A commercial aircraft was vectored to the area, but its pilot reported no visual sighting. The objects eventually faded from radar around 2:08 a.m. on March 10.

About two hours later, on the morning of March 10, search radar picked up another target west of the canal. A T-33 jet from Howard Field was dispatched to investigate. The aircraft came within approximately one hundred yards of the target but reported seeing nothing. Radar operators noted the object moved away rapidly when the jet approached, then stopped and hovered, giving the impression of evasive action. The radar showed the object could accelerate to approximately one thousand miles per hour. Contact was lost at around 2:12 p.m.

On March 10, a radar site on Taboga Island also tracked an object with erratic movement and a triangular flight pattern. The object's speed varied from hovering to roughly one thousand miles per hour, and it again appeared to move away from approaching military jets.

On March 11, a Pan American Airlines pilot reported seeing an unidentified flying object larger than his aircraft traveling southeast. Hawk radar picked up tracks in the same area.

In analyzing the first incidents, the Air Force noted that the radar operators could distinguish the objects from weather formations and clouds. However, military analysts considered several explanations. One report suggested the possibility of one or more weather balloons, since the objects were generally stationary except for altitude changes. Radar could have lost and then regained lock on different balloons at different altitudes, creating the impression of rapid ascent. When the Air Force was asked about weather balloons in the area, they stated that none had been released at that time.

A second report attributed the second radar contact to a false radar target, caused by atmospheric and weather conditions or signal interference, since visual efforts to locate the object failed despite clear daylight conditions.

The third incident, involving a Pan American Airlines DC-4 on March 11, received separate analysis. The radar return was described as about three times the size of a freighter and oblong in shape. At a range of fifty miles, the return appeared exactly like a strong cumulus cloud with a definite cellular structure. At twenty miles, with excellent visibility, the return dissipated and nothing was sighted visually. One analyst concluded that the radar return likely resulted from anomalous propagation, a weather-related phenomenon that can create false radar signals. The analyst noted that the size and visibility characteristics made it unlikely the object was material.

The Air Force's formal evaluation of the Panama Canal Zone sightings is not clearly stated in the file. However, the internal analysis suggests the Air Force favored natural explanations: possible weather balloons for the first incidents and false radar returns caused by atmospheric effects for the others.

The full case file, consisting of 17 pages, is reproduced below as held by the National Archives.