RB-47 Electronic Countermeasures — Multi-Sensor UFO

On July 17, 1957, a USAF RB-47 electronic reconnaissance bomber and its six-man crew encountered an unknown object that was simultaneously detected by three independent sensor systems over a 90-minute period crossing multiple states. The event began at approximately 10:30 PM over Mississippi. The object was first detected by the RB-47's electronic intelligence system as an emission source; the source then became visible to the pilot as a bright blue-white light alongside the aircraft; and simultaneously appeared on the aircraft's own radarscope. The object repeatedly appeared and disappeared on all three systems simultaneously — ruling out sensor error. On multiple occasions the object accelerated away and then reappeared ahead of the aircraft. The encounter was also tracked by ground radar at Duncanville, Texas, and Carswell AFB. The full case was documented by Professor James McDonald, who obtained the classified Blue Book file and crew debriefs through FOIA and testified to Congress in 1968, calling the RB-47 case 'one of the most puzzling in the whole Blue Book collection.' The 2026 NARA archive release includes the NSA signals intelligence records generated from the RB-47's electronic emissions intercept on the night of the event.