Documents / Case file
This CIA archives copy, released in 2026, holds Project Blue Book Special Report No. 14 (Analysis of Reports of Unidentified Aerial Objects). The Air Technical Intelligence Center at Wright-Patterson Air Force Base issued it on 5 May 1955. The study reduced about 4,000 sighting reports from 1947 to 1952 to IBM punched cards, with 3,201 cases charted, and applied chi square tests to compare known and unknown sightings. It concludes that it is highly improbable the reports represent technological developments beyond present-day scientific knowledge.
From the source:Release of 2026-06-12 This is the USAF Project Blue Book with a CIA cover sheet stating the document is "Official Record Copy." With the exception of the handwritten note on the first page, the content of this document has been available on CIA's public website.
I Imeteorological phenomena like small tornadoes, were collected into a category called OTHER. A separate category for the uncommon natural phenomena associated with light reflections or refractions, such as mirages, Isun dogs, inversion-layer images, and distortions caused by airborne ic.e, was established with the title of LIGHT PHENOMENON. Categories for INSUFFICIENT INFORMATION, PSYCHOLOGICAL MANIFESTATIONS, and IUNKNOWN were provided for the sightings that could not be fitted into the preceding identifications. An explanation of their use follows: I INSUFFICIENT INFORMATION - This identification category was assigned to a report when, upon final con Isideration, there was some essential item of information missing, or there was enough doubt abou._t what data were available to disallow I• identification as a common object or some natural phenomenon. It is emphasized that this Icategory of identification was not used as a convenient way to dispose of what might be called "poor unknowns", but as a category for Ireports that, perhaps, could have been one of several known objects or natural phenomena. No reports identified as INSUFFICIENT INFORMA ITION contain authenticated facts or impressions concerning the sighting that would prevent its Ibeing identified as a known object or phenomenon; PSYCHOLOGICAL MANIFESTATIONS - This identification Icategory was assigned to a report when, although it was well established that the ob Iserver had seen something, it was also obvious that the description of the sighting had been overdrawn. Religious fanaticism, a Idesire for publicity, or an over-active imagi nation were the most common mental aber rations causing this type of report; I UNKNOWN - This designation in the identification code was Iassigned to those reports of sightings wherein the description of the object and its maneuvers could not be fitted to the pattern of any known Iobject or phenomenon. IFor the purposes of this study, two groups of identifications were recognized, the KNOWNS (including all identification categories except the UNKNOWNS) and the UNKNOWNS. I All possible identifications provided in the code system, except INSUFFICIENT INFORMATION and UNKNOWN, could be assigned accord Iing to two degrees of certainty, designated "Certain" and "Doubtful". I I 12
Case file, from the pursue collection. The PDF is mirrored here; the original link is above. 312 pages are in the text index: search them above, or from the library's search.