Project 10073 Record Card — Minneapolis, Minnesota, 21 October 1955

This document details a sighting of an Unidentified Aerial Phenomenon (UAP) reported on 21 October 1955, near the Minneapolis-St. Paul International Airport. The primary witness, 1st Lt. William F. Steck of the 432nd Fighter Interceptor Squadron, reported observing an oblong, glowing white object while performing a practice intercept. The object was described as having no tail and executing a sharp 90-degree turn. The sighting lasted approximately two seconds visually, while radar observers, including 1st Lt. Donald E. Chavanu, tracked the object for 15 to 20 seconds. The radar contact was also reported to the KIDSKIN GCI station controller, 2nd Lt. Fredric W. Busch. The pilot estimated the object's speed between 1,000 and 1,500 m.p.h. at an altitude of 25,000 feet. Following the report, the Air Technical Intelligence Center (ATIC) requested additional information via standardized forms, which were completed by the witnesses. After a comprehensive analysis of the weather conditions in the Minneapolis area, ATIC concluded that the sighting was a probable optical and electronic reflection caused by an unusually strong temperature inversion existing between 35,000 and 39,200 feet. The report notes that the alleged 90-degree turn was likely an illusion caused by the observer's aircraft being in a bank during the brief encounter. The documentation includes the original record card, technical information sheets, radar data sheets, and official correspondence between the 31st Air Division and ATIC regarding the final evaluation of the incident.