Report of Unusual Radar Indications — Chicago, Illinois, September 1952

This document compiles reports and correspondence regarding a series of unidentified radar targets observed by air traffic controllers at the Midway Airport in Chicago, Illinois, during the early morning hours of September 2, 1952. Controllers reported that approximately 40 unidentified targets appeared on their ASR and PAR radar scopes between midnight and 0700 hours. These targets were described as being comparable in size to a light aircraft and were tracked at speeds of approximately 175 MPH at altitudes between 2,000 and 6,000 feet. Despite the radar returns, none of the objects were visible to the naked eye from the control tower, nor were they seen by pilots of two F-86 interceptor aircraft scrambled from the 4706th Interceptor Wing at O'Hare International Airport to investigate. The pilots reported flying through the coordinates where the targets appeared on the radar, but observed nothing, not even clouds. The document includes detailed weather data for the period, noting that while there was no inversion layer, the air was unstable. The official conclusion recorded on the Project 10073 record card for this incident is 'Insufficient Data for Evaluation,' with an investigator's note stating that 'Radar would be useful here.' The file also contains a personal account from an individual in Chicago regarding sightings of star-like objects between July 28 and August 1, 1968, which appears to be a separate, unrelated report included in the same file.