At 11:15 pm, a Captain whose name was withheld by the US Air Force was the navigator on a B-29 bomber, USAF 345th Bomber. He saw a bluish cylinder, three times long as wide, with a tail and rapid pulsations, that came in high and fast, made several turns and leveled out under B-29 which was evading mild antiaircraft fire. The sighting lasted 45 seconds.
Project Blue Book case number is 1061, and the encounter occurred in the area of Sinuiju, possibly near Antung, North Korea. It is not well established whether he sighting was on the 23 or the 24th of February 1952. The 345th Bomb Squadron was based in Yakota, Japan.
The case has been considered as the observation of an "unknown" by Project Blue Book, the official US Air Force investigation of the UFO phenomenon (in Blue Book's classification, an "unknown" is a UFO that remains unidentified after thorough investigation, but not because of lack of data or doubts on the witness.)
I would appreciate any additional information on that case at patrick.gross@inbox.com
