RB-47 UFO Pursuit

On the morning of July 17, 1957, a United States Air Force RB-47H electronic reconnaissance aircraft — a six-crew, radar-equipped variant of the B-47 Stratojet assigned to the 55th Strategic Reconnaissance Wing — was flying a training mission in the southern United States when it was intercepted and followed by an unidentified object for approximately one hour and forty minutes across a ground track of over 700 miles, from Mississippi through Louisiana and Texas into Kansas. What made the RB-47 case uniquely significant was its multi-sensor corroboration structure. The object was simultaneously and independently detected through four separate observation channels: the aircraft's electronic countermeasures (ECM) equipment registered a signal on a frequency associated with fire control radar, emanating from the object's direction; the aircraft's own airborne radar acquired and tracked the contact; multiple crew members obtained direct visual sightings of a brilliantly lit blue-white light matching the radar and ECM contacts; and United States Air Force ground radar installations at multiple sites across the southern United States independently tracked the same contact throughout portions of its flight. The convergence of ECM data, airborne radar, visual observation, and ground radar on the same track at the same time eliminated the possibility that any single sensor system or individual perception was producing a false return. The object repeatedly closed to within approximately five miles of the aircraft — well within weapons engagement range — before retreating, executing this approach-and-withdrawal cycle multiple times over the duration of the encounter. The RB-47's crew were trained electronic warfare and reconnaissance professionals whose professional function was the precise characterization of radar emissions and aerial contacts. When the contact finally vanished, it disappeared simultaneously from all four detection systems at the same instant — an organized, total departure rather than the sequential signal degradation of a conventional aircraft flying out of range. Physicist and atmospheric scientist James McDonald, in his formal testimony before the United States House of Representatives Committee on Science and Astronautics in July 1970, described the RB-47 case as 'one of the most scientifically significant UFO cases on record.' Project Blue Book classified the case as unidentified. It remains one of the most extensively analyzed and least resolved multiple-sensor UAP cases in US military aviation history.