PROJECT 10073 RECORD CARD — St. Louis, Missouri, 17 September 1957

This document is a Project 10073 record card and accompanying OSI report regarding an unidentified flying object sighting in St. Louis, Missouri, on 17 September 1957. The witness, a 23-year-old chemistry student at Northwestern University, reported observing a metallic, disc-shaped object approximately 100 yards in diameter. The observer, who was standing on a ladder at the time, described the object as traveling nearly parallel to the horizon before making a circle and disappearing toward the south. The observer noted the sound of the object resembled a 100-cylinder diesel engine heard from a great distance. The report explicitly states that the object did not possess the design of any conventional aircraft and left no vapor trail. The investigation, conducted by Special Agent Charles F. Crutchfield of the 12th District OSI, included consultation with a meteorologist from the St. Louis Weather Bureau. The meteorologist indicated that, given the prevailing wind conditions at the time, a weather balloon could not have drifted over the city. While the report suggests the possibility that the object was a jet aircraft taking off from Lambert Field, the short duration of the sighting—approximately seven seconds—led officials to conclude there was insufficient data for a definitive evaluation. No physical evidence, photographs, or radar contacts were associated with the incident.