North Korea, May 1952May 1952

On May 15, 1952, two F-86 fighter pilots flying a sweep over North Korea spotted a bright, silver object moving at high speed through the sky. The lead pilot, a 51st Fighter-Interceptor Group officer with 56 combat missions, saw it first. His wingman, Lieutenant McCarthy with 27 combat missions, called out the object at the 9 o'clock position (to the left) and below them. It was roughly the size of a B-29 bomber as viewed from their altitude of 30,000 feet.

The object was oval in shape and appeared to be rolling as it passed beneath the two F-86s. It traveled on a straight path from left to right, leaving behind white puffs of what looked like a contrail at irregular intervals. The pilots estimated its speed at between 1,200 and 1,500 miles per hour. The entire sighting lasted only 3 to 5 seconds before the object disappeared from view. The Air Force investigators who interviewed the pilots considered both men highly reliable and credible witnesses.

The intelligence officers reviewing the case noted a major weakness in the evidence. Without fixed reference points on the ground, the pilots could not be certain of the object's actual distance, altitude, or speed. Physiological limits on human perception made precise estimates of size and distance unreliable when observing a bright flash in the sky. The file states there was "no indication as to what might have caused the light."

Later reports from the Korea theater described sightings of lighted balloons in the same general area during this period. Intelligence officers suggested these balloon sightings might explain many of the unidentified objects reported over North Korea, though no definitive link to this particular May 15 sighting was established. The case file does not state a final Air Force conclusion on what the pilots saw. The complete case file, consisting of 9 pages, is reproduced below as held by the National Archives.