Project Blue Book Special Report (second copy)

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.

Ol
ingsSightject
XI
O
°
J5Numl
300
275
250
225
200
175
150
125
100
75
50
25
-90
All object sightings
Sun rise
Unknown object, sightings
Suniset
-60 -30 + 30 +60 +90 +60 +30
Angle of Elevation of The Sun
-30 -60 - 9 0
FIGURE 4 0 FREQUENCY OF OBJECT SIGHTINGS BY ANGLE OF ELEVATION OF THE SUN, INTERVALS
OF 10 DEGREES OF ANGLE
A-7336