Project 10073 Record Card — Sighting over Sea of Japan, 23 December 1957

On December 23, 1957, at 1243Z, an aircraft commander from the 67th Tactical Reconnaissance Wing reported a sighting over the Sea of Japan, east of Vladivostok. The witness observed a projectile passing over the tail of the aircraft. The object was described as having a long trail and traveling in an arcing course before disappearing in a very bright explosion, likened to a flash bomb. During the incident, the aircraft's radar was jammed and could not be tuned out. The aircraft was flying at an altitude of 35,000 feet with an airspeed of 485 knots. The incident was documented via a Project 10073 record card and a subsequent disposition form dated February 13, 1958. Official evaluation by AFCIN-4E1 concluded that there was insufficient data on the radar return to make a definitive assessment. Furthermore, the disposition form noted that a large number of unusual electronic signals and evidence of jamming activity had been observed in the Far East region during that period. The report was originally classified as Secret and was later declassified in 1969.