Type: Military Radar Records
Source: United States Air Force Air Defense Radar Stations
During the RB-47 electronic intelligence encounter of July 17, 1957, several United States Air Force ground radar installations independently tracked unidentified targets corresponding with observations made aboard the RB-47H aircraft. These radar contacts provided an important layer of corroboration beyond the aircraft's onboard electronic intelligence equipment and visual observations.
As the RB-47 crossed the southern United States, radar operators monitored unidentified returns that appeared to maneuver in relation to the aircraft's position. Communications between radar facilities and the RB-47 crew assisted controllers in comparing airborne observations with independently acquired radar data.
According to the official investigation, radar operators observed targets displaying unusual flight behavior, including rapid acceleration, abrupt changes in heading, and movement inconsistent with conventional aircraft operating within the region. During portions of the encounter, the radar contacts corresponded closely with the unidentified electromagnetic emissions detected by the RB-47's Electronic Warfare Officers and with visual observations reported by members of the flight crew.
Project Blue Book investigators examined the radar information alongside crew testimony, ELINT observations, weather records, and operational data. Although investigators evaluated potential explanations including anomalous propagation, radar malfunction, and known aircraft, they were unable to identify a conventional explanation capable of accounting for the combined radar, electronic, and visual evidence.
The ground radar observations remain a significant component of the RB-47 case because they were recorded independently of the aircraft itself. Together with the ELINT records and eyewitness testimony, the radar tracking data helped establish one of the strongest multi-sensor military UAP cases investigated during the Project Blue Book era.