USAF RB-47 Electronic Warfare Intercept

What Happened

In the early morning hours of July 17, 1957, a multi-sensor military encounter occurred over the south-central United States that remains one of the most technically documented events in the history of aerial phenomena. The incident involved an Air Force RB-47H Stratofortress reconnaissance aircraft attached to the 55th Strategic Reconnaissance Wing, operating out of Forbes Air Force Base in Topeka, Kansas.

The RB-47H was an electronic reconnaissance and electronic countermeasures (ECM) aircraft carrying a specialized six-man crew: three flight officers in the forward pressurized cockpit (pilot Major Lewis D. Chase, co-pilot Captain James H. McCoid, and navigator) and three electronic warfare officers (EWOs) stationed in the pressurized lower bay (Captains Frank B. McClure, John J. Barnes, and an EWO operating passive electronic search receivers). The aircraft was equipped with advanced direction-finding pulse analyzers and radar monitors specifically designed to detect, track, and analyze radar emissions from Soviet air defense installations.

While conducting a simulated radar-bombing calibration mission over the Gulf of Mexico off the coast of Mississippi and Louisiana, Captain Frank McClure, operating the #2 electronic monitor (an ALA-6 direction-finder tuned to approximately 2,800 megahertz, standard S-band radar frequency), detected an intense radar signal matching a conventional ground radar pulse. However, the signal originated not from the ground, but from an airborne position off the aircraft's starboard wing. The signal paced the aircraft, moved rapidly around it, and subsequently crossed the jet's nose to the port side.

Moments later, near Meridian, Mississippi, pilot Major Chase established visual contact through the cockpit windscreen: he observed a blinding, blue-white light, the size of a large airliner, approaching the jet at high speed. The object executed a series of incredible maneuvers across four states—Mississippi, Louisiana, Texas, and Oklahoma—before concluding near Fort Worth, Texas. Over an 800-mile flight path spanning more than an hour and a half, the object repeatedly circled the aircraft, matched its speed, disappeared, and reappeared, while being tracked simultaneously by the onboard electronic warfare receivers, the flight crew's eyes, and civilian ground radar.

Witnesses and Sensor Evidence

The RB-47 encounter is recognized by scientific analysts as an extraordinarily high-grade case because the physical presence of the object was confirmed across three separate, independent sensory modes:

• Electronic Countermeasures (ECM) Monitors: The ALA-6 receiver on board the RB-47 locked onto a powerful microwave radar signal emitting at approximately 2,800 MHz with a pulse repetition frequency (PRF) of 600 pulses per second and a pulse width of 2.0 microseconds. The signal was verified by Captain McClure and Captain Barnes on separate directional monitors, confirming a solid physical transmitter emitting microwave radiation in real time.
• Visual Cockpit Confirmation: Major Chase and Captain McCoid visually observed the source of the emission as an intensely luminous, steady blue-white light. When Chase pushed the jet into maximum afterburners to close distance, the object instantly accelerated away at hypersonic speed. At one point, the light plummeted vertically from 30,000 feet to 15,000 feet in seconds, while the electronic monitor tracked the signal descending at the exact same rate and vector.
• Ground Radar Tracking (Carswell AFB / GCI): As the RB-47 crossed into Texas airspace, Major Chase contacted the ground-controlled interception (GCI) radar station at Duncanville (Fort Worth). The ground radar operator confirmed on scope that he was tracking both the RB-47 and a second, separate unidentified target pacing the bomber. When the object suddenly stopped its motion and hovered stationary over Texas, both ground radar and the airborne ECM system tracked the target in the identical spatial coordinate.

Official Investigations

Strategic Air Command (SAC) command staff debriefed the crew immediately upon landing at Forbes AFB. Project Blue Book received preliminary reports but never conducted a thorough on-site investigation, ultimately categorizing the file as "unidentified" with notes suggesting atmospheric refraction.

The case received its most rigorous academic re-investigation during the late 1960s from Dr. James E. McDonald, professor of atmospheric sciences and senior physicist at the University of Arizona. McDonald tracked down the original crew members, secured declassified ECM maintenance logs, and obtained complete flight trajectories. In July 1971, McDonald published a comprehensive technical paper in the Journal of the American Institute of Aeronautics and Astronautics (AIAA), presenting the RB-47 case as an undeniable demonstration of an anomalous physical object emitting structured electromagnetic radiation.

The University of Colorado Condon Committee also analyzed the encounter as Case 56. The committee's lead radar analyst, physicist Dr. Gordon Thayer, conceded that if the ECM telemetry and ground radar tracking were synchronized with the visual observations, the event was inexplicable. However, the final Condon Report speculated that the ground radar, visual lights, and ECM signals might have been independent coincidences, a conclusion McDonald vigorously criticized as statistically absurd.

Proposed Explanations

Ground Radar Reflection / Second Aircraft: Skeptics, including aviation journalist Philip J. Klass, argued that the ECM system picked up reflections from a surface radar station (such as an FAA airport surveillance radar) and that the visual light was a civilian airliner or bright star. However, an airliner cannot drop 15,000 feet in three seconds, cannot outrun an RB-47 in full afterburner, and ground radar confirmed a single target operating in synchronized proximity to the bomber across four state lines.

Meteor or Bolide: Some initial Air Force commentary suggested a shooting star. However, meteors burn out within two to five seconds; they do not maintain sustained formation flights with a strategic bomber for an hour and a half, circle behind an aircraft, or emit 2,800 MHz electromagnetic radar pulses.

Atmospheric Temperature Inversion: The hypothesis that temperature inversions generated false radar reflections was examined and rejected by atmospheric physicist James McDonald. Weather balloon soundings along the flight corridor revealed no sharp thermal inversions capable of ducting radar beams, and atmospheric ducting cannot produce a localized 2,800 MHz transmitter that matches flight maneuvers verified visually by combat aviators.

Current Status

The 1957 RB-47 incident remains completely unexplained by official military or scientific bodies. It stands in the historical literature as a gold-standard military electronic intelligence (ELINT) encounter.

The case demonstrated beyond reasonable doubt that the unidentified phenomenon was capable of interacting with and emitting the exact electromagnetic frequencies utilized by modern radar systems, reinforcing the view of defense scientists that the phenomenon represents a physical, technological reality requiring rigorous electronic surveillance.