Project 10073 Record Card: Michigan-Wisconsin Sighting, 18 September 1951

On 18 September 1951, radar stations within the Great Lakes region, specifically P-31 (Elkhorn) and P-34 (Empire), tracked multiple unidentified targets over Michigan and Wisconsin. The observations, which lasted approximately three hours, consisted of intermittent radar blips described as oblong in shape and slightly larger than a standard large aircraft. The targets exhibited high speeds, with estimates reaching 6,000 mph, though altitude could not be determined due to the speed of the objects. The flight path of these targets was noted as progressing to the East and North. In response to the radar activity, two F-86 aircraft were scrambled to intercept the targets, but the mission resulted in negative findings. Adjacent radar stations also reported encountering similar plots during the same timeframe. An investigation into the incident, documented in an Air Intelligence Information Report (IR-44-51E) dated 23 March 1952, concluded that the radar returns were likely the result of atmospheric ducting. This conclusion was supported by meteorological data indicating heavy ground fog and high moisture content in the area at the time of the sighting. The report notes that similar phenomena had occurred in the region previously under comparable weather conditions. The document includes a map of the subject area and was distributed to the Air Defense Command and the Air Materiel Command.