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.
“Harder”1 page
I I I These 12 sightings can be classed into four categories on the basis of their shapes, as follows: ( l} Propeller shape - Case I I (2) Aircraft shape - Cases II and III I (3) Cigar shape - Cases IV and V I (4) Elliptical or disc shape - Cases VI to XII The criterion for choosing the above sightings was that their descrip I tions were given in enough detail to permit diagrams of the objects to be I drawn. It might be noted here that in all but one of these cases (Case XI) the observer had already drawn a diagram of what he had seen. The objective of this section of the study was the conceiving of a I model, or models. The requirement that the description be detailed is an I important one, and was the easiest to determine in the re-evaluation pro gram. However, a good model ought to satisfy the following conditions as well: I ( 1) The general shape of the object and the maneuvers it performed should fit the reports of many of the UNKNOWNS and thus explain them. I (2) The observer and the report should be reliable. I (3} The report should contain elements which should have been observed with accuracy, and which eliminate the I possibility that the sighting could be ascribed to a familiar object or to a known natural phenomenon. I ( 4} The model should be derived from two or more good UNKNOWNS between which there is no essential conflict. I It can be shown that it is not possible to deduce a model from the 12 cases that will satisfy all of these conditions. The following case-by-case I discussion of the 12 good UNKNOWNS will illustrate this point: I ( 1) Case I does not satisfy Conditions 1 and 4. The reported shape of this object is not duplicated in any of the other UNKNOWNS. I I • (2) Case II does not satisfy Conditions 1 and 3. There are very few UNKNOWNS in the aircraft shape classification. In addition, the unusual characteristic of this sighting I (i.e., the red glow) could have been reflection of the lights of Flint from the objects if they were either birds or aircraft. 91 I
Case file, from the pursue collection. The PDF is mirrored here; the original link is under it. 312 pages are in the text index: search them above, or from the library's search.