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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.

to
60
Total Less Unknown
Per Cent
50 40 30 20 10 0
Sunlight on
mirror or
aluminum
Sunlight on
plaster,
stone or soil
Brighter
than moon
Like moon
Duller
than moon
Not stated
10 20
Unknown
Per Cent
30 40 50 60
I
FIGURE 23 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY LIGHT BRIGHTNESS,
1947-1952
A-75 01

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.