Korea, October 1952October 1952

On the morning of October 16, 1952, two U.S. Air Force pilots flying a T-6 training aircraft over Korea spotted something unusual. First Lieutenant William H. Hooper was in the front cockpit and First Lieutenant Thomas A. O'Neill was in the back, conducting a combat mission near the front lines. At 0550 (5:50 a.m.), O'Neill noticed what he thought was a strange aircraft flying at about 6,000 feet, heading east at roughly 200 mph. The object was perfectly round and metallic silver in color, about 25 feet across.

When Hooper got a look at it, the object seemed to slow down and then stop, hovering over an area identified as grid square DT2942. The pilots disagreed on how long it hovered, with Hooper estimating 15 seconds and O'Neill saying only 1 to 2 seconds. As soon as Hooper dipped the right wing to get a better view, the object sprang to life, accelerating sharply to the east-northeast at an estimated 800 mph and disappearing into the haze over the coastline. The entire sighting lasted about three minutes. Both pilots noted the object had no visible means of propulsion, made no sound, and showed no moving parts or protrusions of any kind.

Intelligence officers investigating the case noted that enemy forces in the area had been known to use captive balloons, tethered by cable. A report from June 1952 described a large enemy balloon that had been spotted in roughly the same area, sometimes rising and falling on its cable, sometimes appearing round and sometimes egg-shaped. The investigators concluded the October sighting was probably the same captive balloon being released or rising on its tether, with its movement misinterpreted as powered flight. Wind and changes in elevation on the tether, they reasoned, could explain the hovering and the apparent acceleration. The Air Force's final evaluation listed the sighting as "probably balloon," though a note in the file said the evidence was insufficient to rule out other possibilities.

The complete case file, held by the National Archives, spans 10 pages.