Air Force sanitized UFO sightings for 22 years
By June Hargrove ·
Observers gave their names and addresses for a 22-year Air Force study, yet the reasons for withdrawn photographs and sanitized case files remain unexplained.
The National Archives catalog entry for "Project Blue Book Case Files on Sightings of Unidentified Flying Objects (UFOs)" describes a vast intake system for the unexplained. It is not the sightings themselves that are presented here, but the scope-and-content description of how the United States Air Force tracked those sightings from June 1947 through December 1969. For a radar officer, the interest is not in what was seen, but in how the data was logged, filed, and transferred across three different command structures over twenty-two years.
The file's catalogue entry records a shifting chain of custody. Between 1947 and 1951, the records were maintained by the USAF Air Material Command Intelligence Department Technical Intelligence Division. From 1951 through March 1952, they moved to the USAF Office of the Deputy Chief of Staff Operations Office of the Director of Intelligence Air Technical Intelligence Center. Finally, from March 1952 until the project's end in 1969, the files were held by the USAF Air Force Systems Command Foreign Technology Division Project Blue Book Office and its predecessors.
Control Sheets and Monthly Lists
The catalog describes a two-part organization. The first subseries consists of the sighting case files. These are the primary repositories for the information the Air Force gathered about specific sightings, with each file relating to a single event or a group of closely related events. The content of these files included reports from observers, correspondence between the Air Force and those observers, and clippings from newspapers and magazines. The records also include reports of analyses conducted on physical evidence and photographs.
While some reports arrived via telegram or letter, the file's description notes that most sightings were submitted via a standardized Air Force questionnaire. This form required the observer to provide their name and address, the date and hour of the sighting, and a description of what was seen.
To manage this volume of data, the Air Force utilized control sheets. According to the archival description, each case file contains a control sheet that summarizes the sighting report and lists the Air Force's specific "explanation and conclusions for the sighting." These summaries were augmented by monthly lists of sightings. For every entry, these lists recorded the date, location, and name of the observer, alongside an "evaluation of the sighting report."
Withdrawn Photographs
The second subseries contains photographs that were withdrawn from the primary case files. The archival record indicates that the case files utilize cross-reference sheets to point the reader toward these photographs.
This system of cross-referencing extended beyond the photographs in the second subseries. The catalog records that citations exist for other media and materials submitted with the reports. These materials are housed in separate series, including "Project 'BLUE BOOK', 1954-1966" (National Archives Identifier 542184), "Project Blue Book Motion Picture Films, 1950 - 1966" (National Archives Identifier 61934), and "Sound Recordings Relating to Project Blue Book Unidentified Flying Object (UFO) Investigations, 1953 - 1967" (National Archives Identifier 1142703). Physical objects are listed under "Project Bluebook Artifacts, 1952 - 1969" (National Archives Identifier 23857160).
Sanitized Versions
The archival description concludes by noting the existence of a parallel set of records. Redacted copies of the case files are maintained in a separate series titled "Sanitized Version of Project Blue Book Case Files on Sightings of Unidentified Flying Objects, 1947-1969" (National Archives Identifier 597821).
Public record establishes that Project Blue Book was headquartered at Wright-Patterson Air Force Base in Ohio and was designed to determine if UFOs posed a threat to national security and to analyze the data scientifically. The catalog entry shows the logistical side of that mission: a process of questionnaires, control sheets, and cross-referenced media.
The record leaves the nature of the "sanitization" in the second series unexplained. It does not state what was removed from the original files or why certain photographs were withdrawn into a separate subseries. The catalog simply notes that the sanitized version exists under a different identifier.