Project 10073 Record: UFO Radar Returns, 6 Aug 65, Louisville, Ky & Chicago, Ill

This document is a collection of correspondence and reports regarding a radar sighting of two unidentified objects on August 6, 1965, in the Chicago, Illinois area. The initial report, filed by the Chicago Air Defense Sector, indicated that two objects were detected by ground radar at approximately 100,000 feet. The objects were described as having slow movement and no constant heading, appearing and disappearing sporadically on the radar scope. The observation lasted for 45 minutes. The Foreign Technology Division (FTD) requested a formal radar analysis of the incident. In the subsequent evaluation, Lt. Colonel John W. Vega of the Electronics Directorate stated that the information provided was insufficient for a creditable analysis. He noted a significant discrepancy in the reported movement, calculating that the objects traveled 620 nautical miles in 45 minutes, which contradicted the description of 'slow movement.' He suggested that the objects were likely balloons, as certain materials can be detected by radar, and recommended that the possibility of a temperature inversion be investigated. Further correspondence from the Chicago Air Defense Sector clarified that the two radar sites involved were not tracking the same objects and that there were no known temperature inversions in the area at the time of the detections. The final conclusion maintained that balloons remained the best explanation for the observation given the lack of further information regarding the objects' speed and movement.