Moses Lake Air Force Base, WashingtonMay 1949

On the afternoon of May 21, 1949, radar operators at Hanford Atomic Plant in eastern Washington spotted what they believed was a flying saucer and called Moses Lake Air Force Base for help. The operator reported a disc-shaped object standing still, then suddenly accelerating southeastward at a speed faster than any jet fighter then in service. The base scrambled an F-82 twin-engine fighter (call sign Gertrude 20, piloted by Gardner) to intercept it.

Ground crews and the fighter pilot all reported seeing a round, white or silver object moving through the sky at roughly 10,000 to 15,000 feet altitude, traveling northeast. Radar operators tried to track the target, but the signal was weak and spotty, making it hard to follow the aircraft. The fighter managed only two course corrections before losing radar contact about five minutes after takeoff. Meanwhile, the Hanford operator reported bits of paper falling in the area near the Rattlesnake Mountains, approximately 6 inches square, colored red on one side and green on the other.

The F-82 was directed to investigate the paper drop while also searching for signs of the object. The search continued with poor radar coverage and found nothing. Within an hour, the Hanford operator called back with the answer: the papers were advertisements for an air show at Richland, dropped by a PT-19 aircraft (a training plane) piloted by Don Wise as part of an air rodeo. The papers had indeed fallen into the restricted military zone.

In its analysis, the Air Force concluded that two separate events had occurred on the afternoon of May 21. The first was the actual sighting of an unidentified object by Hanford personnel using a telescope and by the base's operations crew. The second was the accidental pamphlet drop by a civilian aircraft, likely causing some confusion during the alert. The file notes it is believed these two incidents were unrelated. No weather balloons were in the air at the time, and the weather section confirmed they did not launch such balloons from Moses Lake. The complete case file of 14 pages is reproduced below as held by the National Archives.