Documents / Report
This is Project Blue Book Special Report No. 14, "Analysis of Reports of Unidentified Aerial Objects," Project No. 10073, dated 5 May 1955. The study reduced about 4,000 sighting reports received by the U.S. Air Force between June 1947 and December 1952 to IBM punched cards and analyzed them statistically, including chi square tests comparing knowns with unknowns. It concludes that the reports very probably do not represent technological developments beyond present scientific knowledge, and it notes that no case produced physical evidence.
forgetting the subjectivity of the data at the time that conclusions are drawn from the analysis. It must be emphasized, again and again, that any conclusions contained in this report are based NOT on facts, but on what many observers thojight and estimated the_ true facts to be. Altogether, the data for this study consisted of approximately 4, 000 reports of sightings of unidentified aerial objects. The majority were re- ceived through military channels or in the form of observer-completed questionnaires; a few were accepted in the form of direct letters from un- questionably reliable sources. Sightings made between June, 1947, and December, 1952, were considered for this study. Sightings alleged to have occurred prior to 1947 were not considered, since they were not reported to official sources until after public interest in "flying saucers" had been stimulated by the popular press. REDUCTION OF DATA TO MECHANIZED COMPUTATION FORM As received by the Air Technical Intelligence Center, the sighting reports were not in a form suitable for even a quasi-scientific study. A preliminary review of the data indicated the need for standardized interro- gation procedures and supplemental forms for the reduction of currently held and subsequently acquired data to a form amenable to scientific appraisal. The plan for reduction of the data to usable form consisted of a pro- gram of development comprising four major steps: (1) a systematic listing of the factors necessary to evaluate the observer and his report, and to identify the unknown object observed; (2) a standard scheme for the trans- fer of data to a mechanized computation system; (3) an orderly means of relating the original data to all subsequent forms; and (4) a consistent pro- cedure for the identification of the phenomenon described by the original data. Questionnaire The first reports received by ATIC varied widely in completeness and quality. Air Force Letter 200-5vW and Air Force Form 112(1) w e r e attempts to fix responsibility for and improve the quality of the reports of sightings. To coordinate past efforts and to provide standardization for the (1) A modified Air Force Form 112 lists pertinent questions to be answered in regard to an unidentified-dbject sighting. (2) Air Force Letter 200-5 places responsibility with the Air Force for the investigation, reporting, and analysis of unidentified aerial objects. This letter is dated 29 April 1952.
Report, cited by the archive. The PDF is mirrored here; the original link is above. 309 pages are in the text index: search them above, or from the library's search.