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.
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
CODE 50 SHAPE PARAMETER a/b
X - Variable
y
0 - o.o
l - 0.05
2 - 0.1
3 - 0.2
4 - 0 • .3
5 - 0.5
6 - 0.75
7 - 0.9
8 - 1.0
9 - Other
CODE 51 SUBTENDED VISUAL ANGLE
{Referred to sun diameter)
X - Decreased in size
y
0 - 0.1
l - 0.2
2 - 0.5
.3 - o.75
4 ... 1.0
5 - 1.5
6 - 2.0
7 - 4.0
8 - 4.0 to 10.0
9 - Other
CODE 52 LIGHT BRIGHTNESS (Intens.llzl
X Decreased
CODE 53 ANGULAR VELOCITY
X Variable
yy
0 Sunlight on mirror
l Sunlight on aluminum
2 Sunlight on plaster
3 Sunlight on stone
4 Sunlight on soil
5 Brighter than moon
6 Like moon
7 Duller than moon
8 Barely visible
9 Other
CODE 54 ANGULAR ACCELERATION
(Change in Angular Velocity)
X Variable
y
O Zero, v=constant
l Increasing slowly
2 Decreasing slowly
3 Increasing fast
4 Decreasing fast
5 Increasing very fast
6 Decreasing very fast
7
8
9
293
0 Zero
1 Very slow, 1° per second
2 Slow, .3° per second
.3 Moderate, 60 per second
4 Rapid, 12° per second
5 Very fast, 30° per second
6 Extremely fast, 900 per second
7 More than 900 per second
8
9 Other
CODE 55 APPEARANCE BEARING
X
y
0 - N
1 - NE
2 - E
3 - SE
4 - s
5 - SW
6-W
7 - NW
8
9 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.