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Project Blue Book Special Report No. 14: Analysis of Reports of Unidentified Aerial Objects

United States Air Force, Air Technical Intelligence Center · 1955-05-05 · 309 pages · text from the file's own layer

Special Report No. 14 was issued by the U.S. Air Force's Air Technical Intelligence Center on 5 May 1955. It is a statistical study of about 4,000 reports of unidentified aerial objects from June 1947 to December 1952. The reports were reduced to IBM punched cards and analyzed with methods including chi square tests. The report concludes that the reports it examined are very unlikely to represent technology beyond present scientific knowledge, and it notes that no case produced valid physical evidence.

physical matter in any case of a reported unidentified aerial object, this
was not assumed to be prima facie evidence that "flying saucers" did not
exist. I
In those cases in which an attempt to reduce the information to a
factual level failed completely, the report was eliminated from further con-
sideration, and thus not included in the statistical analysis. About 800
reports of sightings were eliminated or rejected in this manner. Most of
these reports were rejected because they were extxexoely nej^uljous; the
rest were rejected because they contained highly conflj^cjting statements.
The second step in evaluation, the rating of the observer and his
report, logically followed the first step, the reduction of the data to usable
form. Ratings were assigned on the basis of the following factors of in-
formation, 'considered in relation to one another:
(1) The exp_e_xience of the observer, deduced from his
occupation, age, and training;
(2) The consistency among the separate portions of the
description of the sighting;
(3) The general quality and compljeteness of the report;
(4) Consideration of the observer' s fact-reporting ability
and attitude, as disclosed by his manner of describing
the sighting. '
In cases in which insufficient information was available to make a judgment
of the observer or report, none was made, but the report was accepted for
the statistical study. •
The third step in the process of evaluation, the attempted identifica-
tion of the object or objects sighted, was done twice, fi^gj^by the individual
who made the transcription of the data (the preliminary identification), and
later (the final identification) by a conference of four persons, two repre-
sentatives from ATIC and two from the parcel of consultants. Although
representatives of ATIC participated in making the final identifications, it
must be emphasized that any previous identification of a sighting made by
ATIC was not introduced or referred to in any way.
In the coding system, the choices provided for final identifications
were based on ATIC s previous experience in analysis of the data. They
had found that the majority of sightings could be classified as misinterpre-
tatiorxs of common objects or natural phenomena. Accordingly, categories
for objects most frequently present in the air were provided. Balloons,
aircraft, astronomical bodies (such as meteors), birds, and clouds or dust
were recognized as major categories. The less frequent, but common
objects, such as kites, fireworks, flares, rockets, contrails, and
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Cases discussed

About this file

Analysis, from the classic collection. 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.