Historical Case Studies: Three UFO Radar Cases _______________________________________ Selfridge Air Force Base, Michigan. March 9, 1950 p. 1 Bentwaters-Lakenheath RAF, Suffolk, UK. August 13-14, 1956 p. 5 Minot Air Force Base, North Dakota. October 24, 1968 p. 16 Thomas Tulien Sign Oral History Project 2018 Sign Oral History Project SELFRIDGE AIR FORCE BASE RADAR CASE March 9, 1950 On the evening of March 9, 1950, at Selfridge Air Force Base near Mount Clemens, Michigan, a crew of three radar controllers was busy monitoring the night flying units of the 56th Fighter-Interceptor Group at Selfridge Air Force Base. Shortly after sundown, Lt. Francis E. Parker arrived for duty in the radar station, relieving Lt. Frank Mattson on the AN/CPS-5 radarscope while establishing contact with the F-80 Shooting Star pilots that were already airborne. The crew, including Mattson, Sgt. McCarthy, and Cpl. Melton, mentioned to Parker that they had been observing an intermittent target on the height range indicator (HRI) scope of the AN/CPS-4 radar at 45,000 feet altitude and over. At this time, the target was not visible on either radarscope, and since the highest assigned altitude of the F-80s was limited to 24,000 feet, Parker attributed the reports to radio-frequency interference or crew inexperience. But over the next fifteen minutes the crew repeatedly reported a target rapidly changing altitudes on the HRI scope. Eventually, Parker was able to break from monitoring the F-80s long enough to observe the target, which presented “a very narrow and clear-cut presentation on the HRI scope” at 47,000 feet with a range of 70 miles. The Lockheed F-80 Shooting Star was the first turbojet-powered combat fighter to enter USAAF service in the final days of World War II. Sign Oral History Project Further indications of what Parker described as an “aircraft” were picked up with increasing regularity over the next 45 minutes to an hour. Curiously, during this time the target seemed to stay in the area where the fighter pilots were flying, occasionally appearing to approximate their courses—though at 20,000 feet above them. During the course of the events, Parker was able to speak to the Lockheed F-80 fighter pilots over the VHF radio to determine their exact altitude, bearing, and speed. This provided a means to calibrate the accuracy of the radar systems and eliminate the possibility of any internal malfunction during the actual observation period. In addition, the radar operators were monitoring two distinct radar systems—a CPS-5 radar operating in the L-band (“long” wave) frequencies, designed to provide a search to 60 miles (though effective to 210 miles) at 40,000 feet; in conjunction with a separate height finding radar set with a vertical antenna designated CPS-4 with a range of 90 miles operating in the S-band (“short” wave) of frequencies. The MIT AN/CPS-4 system was recently installed as part of a preliminary establishment of an early-warning radar system to guard against Soviet invasion. Because of the significant differences in frequencies of the two radar systems any temperature inversion or atmospheric anomalies, which are extremely sensitive to frequency, would not display correlating and consistent returns on both radarscopes as was observed. Further, according to Lt. Parker’s report, the target indication was definitely not that of a cloud or atmospheric phenomenon. I checked [with] pilots in the area by VHF and was assured by the F-80 pilot at the highest altitude that he was at 24,000 feet. The clarity, narrowness, and definition of the presentation were definitely that of an aircraft. The target gave a similar presentation to that given by an F-80, and if anything narrower. Furthermore, the crewmembers reported from indications on both radarscopes the target hovering in one position. During a four to five minute period it traversed from due west (270 degrees) at 78 miles, to north (358 degrees) at 53 miles, at an altitude of 45,000 feet— resulting in a speed approaching 1,500 mph for this run. For reference, the normal cruise speed of an F-80 was 410 mph; and Martin Shough has noted that even a factor-2 error in the calculation results in a speed well in excess of the fastest operational jet in 1950 (Shough, 2002). Though unable to substantiate the speed himself, Parker conceded, “I knew only that the target was very fast.” This seemed to heighten his interest, and by momentarily turning around and watching the HRI scope he was able to observe several extreme instances of gaining and losing altitude, remarkably at times up to 20,000 feet very rapidly. Finally, he was able to identify the “aircraft” on his radarscope, and simultaneously on the HRI scope as the target began to move away from the area to the southeast. With clear indications on both scopes, he began recording the range and azimuth on the minute, while McCarthy recorded the altitudes on the HRI over the next six minutes. The results are indicated in the following graph. Following this, the unidentified target began fading from the radarscope, though for short periods they were still able to observe it for durations of one and two minutes. Once more, at a distance of 110 miles it appeared to hover for two minutes, before fading from the scope at 120 miles for the last time. 2 Sign Oral History Project In reference to the recorded data, Parker noted, “These figures, although not as spectacular as some of the climbs and speeds I observed, show definitely the erratic speed and altitude changes,” clearly implying that the flight characteristics were not consistent with aircraft typically observed on his radarscopes. In fact, no aircraft known to be flying in 1950 could approach the performance envelope of the target, or remain stationary at high altitudes for up to two minutes. Time, speed, range, and altitude plotted over a six-minute period at Selfridge Air Force Base in Michigan on March 9, 1950 (Shough, 1987). For example, the one-minute plots logged by the controllers indicate a climb rate of up to 7,000 feet per minute (fpm), and speeds over 450 mph at altitudes above 35,000 feet. For comparison, the maximum rate of climb of a clean F-80 (with no external loading) was 4,950 fpm, and a calibrated airspeed of 310 mph at sea level. However, according to the F-80C flight manual, these specifications decrease proportionally with increase in altitude (and the consequent decrease in air density). At 25,000 feet, the standard rate of climb decreases by more than half, to 2,250 fpm at an airspeed of 260 mph, and more so as the plane approaches the service ceiling around 40,000 feet. As an experienced pilot and radar controller, Parker would have been cognizant of these standards. His report (Parker, 1950) of the incident reached Headquarters, Continental Air Command, Mitchell Air Force Base in New York, where it was reviewed by technical experts, resulting in a classified letter of recommendation forwarded to the Director of Intelligence, Headquarters, U.S. Air Force, in Washington, D.C. The letter corroborated Lt. Parker’s 3 Sign Oral History Project reporting, further emphasizing: The great difference in the frequencies of the L-Band CPS-5 and S-Band CPS-4 radar sets and the evident correlation of observations between these two sets almost rule out the possibility of anomalous propagation effects. Further, the magnitude of the velocity and accelerations of the three dimensional movements of the “object” reported are beyond the capability of known heavier or lighter than air vehicles in controlled flight (O’Brien, 1950). The experts also noted that field experience with the CPS-5 radar system at the ranges and altitudes reported indicate the reflection aspect ratio of the object as comparable to a B-29 Superfortress or greater. The letter concluded with this acknowledgment: “The frequency of reports of this nature has recently increased; instructions have therefore been directed to all radar installations within this command to report scope sightings of unusual objects,” with a further recommendation that all Air Force agencies be reconsidered for submission of unidentified object reports (O’Brien, 1950). Given the historical context in early 1950, at the advent of the Cold War—while lacking any early warning system to effectively guard against a Soviet invasion—Air Force officials had just cause to be concerned about unidentifiable aircraft operating in the vicinity of military facilities, particularly when they exhibited performance characteristics that could not be defended against with current technologies. The Selfridge observations clearly demonstrate the ability of radar to provide reliable, quantitative data in order to demonstrate, in unambiguous fashion, a range of performance characteristics of UFO reports. On two occasions the target appeared to hover in the low- density air found higher up in the atmosphere, an attribute of many UFO reports beyond any aerodynamic capability to this day. In addition, radar provides a means to track UFOs over ranges of hundreds of miles, and often in relation to known aircraft. Parker noted that during a 45-minute period of time “this target seemed to stay in the area in which our fighters were flying, sometimes approximating their courses but 20,000 feet above them,” which infers rational behavior, or an inquisitive nature directed by intelligence. This ability to infer intelligent behavior is an intriguing aspect of UFO radar reports. —Thomas Tulien Sources: Hynek, J. Allen. The Hynek UFO Report. New York: Dell, 1977. O’Brien, Neal. Classified letter from HQ, Continental Air Command, Mitchell AFB, NY to Director of Intelligence, Headquarters, U.S.