Project 10073 Record Card and Air Intelligence Information Report — Phoenix, Arizona, 5 April 1952

This document consists of a Project 10073 Record Card and an Air Intelligence Information Report (IR-1-52) detailing a sighting of three unidentified flying objects over Phoenix, Arizona, on 5 April 1952. The report was compiled by Captain Frederick R. Roeper Jr. of the 127th Pilot Training Wing following a telephone report to Major William H. Casterline, the Base Operations Officer at Luke Air Force Base. According to the four civilian witnesses, three large, circular, dull grey objects—described as resembling unpolished aluminum—were observed performing straight and level maneuvers. The objects were reported to have no wings, flames, smoke, or vapor trails. One witness noted that one object disappeared and then reappeared, after which it was joined by two other objects to form a V-formation. The objects were estimated to be at an altitude of 40,000 feet and traveling north at a speed described as 'half the rate of a falling comet.' Weather conditions at the time were reported as clear with 45-mile visibility and calm winds. The report notes that two F-86 aircraft landed at Luke AFB from Winslow shortly after the sighting, and three F-51 aircraft were en route from Phoenix to Winslow at the time, but none of these military pilots reported seeing the objects. The official conclusion of the Air Intelligence report is that no significance is attached to the sighting, though it suggests that if substantiated by other reports, the information could be reconsidered. The document is marked as unclassified and was subject to periodic downgrading under DOD Directive 5200.10.