Project 10073 Record Card — Sighting Report, 3 May 1958, Flagstaff, Arizona

This document is a Project 10073 record card and associated report detailing an Unidentified Aerial Phenomena sighting that occurred on May 3, 1958, near Flagstaff, Arizona. The sighting was reported by a Marine Corps pilot, identified as Marine-3072, who was flying at an altitude of 35,000 feet. The pilot observed a single, white, elongated object that appeared to be the size of a basketball when held at arm's length. The object was described as motionless and stationary. The sighting lasted for approximately 15 minutes. The object was also detected by radar, specifically verified by S-163 radar. The report includes a preliminary analysis prepared by 1/Lt. Thomas D. R. Park, Chief Director, and information collected by 2/Lt. Gary D. Cool, the Senior Director on duty. The investigators noted that the reporting GCI director was considered highly reliable, and the witness possessed a background in pilot and aircraft engineering. Despite the radar contact, the final conclusion reached in the record card was that the object was 'Probably Balloon.' The document includes handwritten notes and sketches, including a diagram showing the relative positions of the observer, the object, and the town of Prescott, Arizona. The report emphasizes that there were no appendages, such as an instrument package, visible on the object. The weather conditions at the time of the sighting were reported as unknown by the observer, though wind data was provided by the 34th Air Division. The document is classified as unclassified and follows standard reporting procedures for the Air Technical Intelligence Center.