CIA-미확인 이상 현상(UAP)-015, Project Blue Book 특별 보고서 No. 14(미확인 공중 물체 보고서 분석)

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SPECIAL REPORT N0.14
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(ANALYSIS OF REPORTS OF UNIDENTIFIED AERIAL OB1ECTS)
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PROJECT NO. 10073
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I 5 MAY 1955
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AIR TECHNICAL INTELLIGENCE CENTER
WRIGHT-PATTERSON AIR FORCE BASE
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OHIO
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Copy No.
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PROJECT BLUE BOOK
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SPECIAL REPORT NO. 14
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(ANALYSIS OF REPORTS OF UNIDENTIFIED AERIAL OBJECTS)
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PROJECT NO. 10073
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:1 5 MAY 1955
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ii FOR OffIC!Al USt ONlY
(AFR 190-16)
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I AIR TECHNICAL INTELLIGENCE GENTER
WRIGHT-PATTERSON AIR FORCE BASE
o:mo
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No copyright materiel ls contained In this publication,
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TABLE OF CONTENTS
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SUMMARY. vii
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INTRODUCTION
ORIGIN AND NATURE OF DATA 3
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REDUCTION OF DATA TO MECHANIZED COMPUTATION FORM 4
Questionnaire . 4
I Coding System and Work Sheet 6
Identification of Working Papers. 7
Evaluation of Individual Reports 10
I ANALYSIS OF THE DATA. 14
Frequency and Percentage Distributions by Characteristics 14
Graphical Presentation . 16
I Advanced Study of the Data 16
Position of the Sun Relative to the Observer 16
Statistical Chi Square Test 60
The "Flying Saucer" Model 76
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CONCLUSIONS 94
APPENDIX A. TABULATION OF FREQUENCY AND PERCENTAGE
I DISTRIBUTIONS BY CHARACTERISTICS 95
APPENDIX B. WORKING PAPER FORMS 255
I LIST OF ILLUSTRATIONS
Figure l Frequency of Sightings by Year for Object, Unit, and All Sightings 17
Figure 2 Distribution of Evaluations of Object, Unit, and All Sightings for All Years 18
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Figure 3 Distribution of Object Sightings by Evaluation for All Years With Comparisons
of Each Year for Each Evaluation Group • 19
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Figure 4 Distribution of Object Sightings by Evaluation for All Years and Each Year 20
Figure 5 Distribution of Object Sightings by Evaluation Within Months for All Years 21
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Figure 6 Distribution of Object Sightings by Certain and Doubtful Evaluations for
All Years and Each Year • 22
Figure 7 Frequency of Object Sightings and Unknown Object Evaluations by
I Months, 1947-1952. 23
Figure 8 Distribution of Object Sightings by Sighting Reliability Groups With
Evaluation Distributions for Each Group . 24
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Figure 9 Distribution of Object Sightings Among the Four Sighting Reliability
Groups for All Years and Each Year . 25
I Figure 10 Distribution of All Sightings by Sighting Reliability Groups, Segregated
by Military and Civilian Observers, With Evaluation Distribution
for Each Segregation 26
I Figure 11 Distribution of Object Sightings by Reported Colors of Object(s) With
Evaluation Distribution for Each Color Group • 27
Figure 12 Distribution of Object Sightings by Number of Objects Seen per Sighting
I With Evaluation Distribution for Each Group 28
Figure 13 Distribution of Object Sightings by Duration of Sighting With Evaluation
Distribution for Each Duration Group . 29
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LIST OF ILLUSTRATIONS
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Figure 14 Distribution of Object Sightings by Months Among the Eight Duration
Groups for All Years 30
Figure 15 Distribution of Object Sightings by Shape of Object(s) Reported With
Evaluation Distribution for Each Shape Group , 31 I
Figure 16 Distribution of Object Sightings by Reported Speed of Object(s) With
Evaluation Distribution for Each Speed Group . 32
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Figure 17 Distribution of All Sightings by Observer Location for All Years and Each Year 33
Figure 18 Comparison of Known and Unknown Object Sightings by Color, 1947-1952 34
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Figure 19 Comparison of Known and Unknown Object Sightings by Number of Objects
per Sighting, 1947-1952 35
Figure 20 Comparison of Known and Unknown Object Sightings by Speed, 1947-1952 36 I
Figure 21 Comparison of Known and Unknown Object Sightings by Duration, 1947-1952 37
Figure 22 Comparison of Known and Unknown Object Sightings by Shape, 1947-1952 38 I
Figure 23 Comparison of Known and Unknown Object Sightings by Light Brightness, 1947-1952 39
Figure 24 Comparison of Monthly Distribution of Object Sightings Evaluated as Astronomical
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Versus Total Object Sightings Less Astronomical. 40
Figure 25 Comparison of Monthly Distribution of Object Sightings Evaluated as Aircraft
Versus Total Object Sightings Less Aircraft 41
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Figure 26 Comparison of Monthly Distribution of Object Sightings Evaluated as Balloon
Versus Total Object Sightings Less Balloon, 42
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Figure 27 Comparison of Monthly Distribution of Object Sightings Evaluated as Insufficient
Information Versus Total Object Sightings Less Insufficient Information 43
Figure 28 Comparison of Monthly Distribution of Object Sightings Evaluated as Other
Versus Total Object Sightings Less Other 44 I
Figure 29 Comparison of Monthly Distribution of Object Sightings Evaluated as Unknown
Versus Total Object Sightings Less Unknown 45
Figure 30 Characteristics Profiles of Object Sightings by Total Sample, Known Evaluations, ,-
and Individual Known Evaluations, With Unknown Evaluations Superimposed , 46
Figure 31 Frequency of Object, Unit, and All Sightings Within the U. S., 1947-1952, by I
Subdivisions of One Degree of Latitude and Longitude 47
Figure 32 Distribution of Object Sightings by Evaluation for the Twelve Regional Areas of
the U. S., With the Strategic Areas Located 48 I
Figure 33 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
Central East Region 49
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Figure 34 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
Central Midwest Region 50
Figure 35 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
Central Farwest Region 51 I
Figure 36 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
South Midwest Region . 52
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Figure 37 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
South West Region
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LIST OF ILLUSTRATIONS
(Continued)
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Figure 38 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
South Farwest Region . 54
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Figure 39 Diagram of a Celestial Sphere. 56
Figure 40 Frequency of Object Sightings by Angle of Elevation of the Sun, Intervals
of 10 Degrees of Angle. 57
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Figure 41 Frequency of Object Sightings by Local Sun Time, Intervals of One Hour 59
Table Object Sightings 60
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Table II Chi Square Test of Knowns Versus Unknowns on the Basis of Color 62
Table III Chi Square Test of Knowns Versus Unknowns on the Basis of Number 63
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Table IV Chi Square Test of Knowns Versus Unknowns on the Basis of Shape 64
Table V Chi Square Test of Knowns Versus Unknowns on the Basis of Duration of Observation 65
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Table VI Chi Square Test of Knowns Versus Unknowns on the Basis of Speed ti6
Table VII Chi Square Test of Knowns Versus Unknowns on the Basis of Light Brightness 67
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Table VIII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Color 70
Table IX Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Number. 71
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Table X Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Shape 72
Table XI Chi Square Test of Revised Knowns Versus Unknowns on the Basis of
I Duration of Ob~ervation 73
Table XII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Speed 74
Table XIII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Light Brightness. 75
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SUMMARY
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Reports of unidentified aerial objects (popularly termed "flying
saucers" or "flying discs") have been received by the U.S. Air Force
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since mid-1947 from' many and diverse sources. Although there was no
evidence that the ·unexplained reports of unidentified objects constituted
a threat to the security of the U.S., the Air Force determined that all
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rep,orts of unidentified aerial objects should be fovestigated and evaluated
to d,etermine if "flying saucers". represented technological developments
not known to this country.
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In order to discover any pertinent trend or pattern inherent in the
data, and to evaluate or explain any trend or pattern found, appropriate
I methods of reducing these data from reports of unidentified aerial objects
to a form amenable to scientific' appraisal were employed. In general, the
original data upon which this study was based consisted of impressions and
I interpretations of apparently unexplainable events, and seldom contained
reliable measurements of physical attributes. This subjectivity of the data
presented a 'major limitation to the drawing of significant conclusions, but
I did not invalidate the application of scientific methods bf study.
The reports received by the U.S. Air Force on unidentified aerial
I objects were reduced to IBM punched-card abstracts of the data by means
of logically developed forms and standardized evaluation procedures.
Evaluation of sighting reports, a crucial step in the preparation of the data
I for statistical treatment, consisted of an appraisal of the reports and· the
subsequent categorization of the object or objects described in each report.
A detailed description of this phase of the study stresses the careful
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attempt to maintain complete objectivity and consistency.
Analysis of the refined and evaluated data derived from the original
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reports of sightings consisted of (I) a systematic attempt to ferret out any
distinguishing characteristics _inherent in the data of any of their segments,
(2) a concentrated study of any trend or pattern found, and (3) an attempt
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to determine the probability that any of the UNKNOWNS represent observa.:.
tions of technological' developments not known to this country.
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The first step in the 'analysis of the data revealed the existence of
certain apparent similarities between cases of objects definitely identified
.i.nd those not identified. Statistical methods of testing when applied indicated
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a low probability that these apparent similarities were significant. An
attempt to determine the probability that any of the UNKNOWNS represeri'ted
observations of technological developments not known to this country necessi­
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tated a thorough re-examination and re-evaluation of the cases of objects not
originally identified; this led to the conclusion that this probability was very
small.
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The special study which resulted in this report (Analysis of Reports
of Unidentified Aerial Objects, 5 May 1955) started in 1953. To provide the
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study group with a complete set of files, the informatio~ cut-off date was
established as of the end of 1952. It will accordingly be noted that the
statistics contained in all charts and tables in this report are terminated
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with the year 1952. In these charts, 3201 cases have been used. I
As the study progressed, a constant program was maintained for
the purpose of making comparisons between the current cases received I
after I January 1953, and those being used for the report. This was done
in order that any change or significant trend which might arise from
current developments could be incorporated in the summary of this report. I
The 1953 and 1954 cases show a general and expected trend of
increasing percentages in the finally identified categories. They also.show
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decreasing percentages in categories where there was insufficient informa­
tion and those where the phenomena could not be explained. This trend had
been:. anticipated in the light of improved reporting and investigating pro­ I
ceduJ;"es.
Official reports on hand at the end of 1954 totaled 4834. Of these, I
425 were produced in 1953 and 429 in 195'!. These 1953 and 1954 indi­
vidual reports (a total of 854), were evaluated on the same basis as were
those received before the end of 1952. The results are as follows:
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Balloons - 16%
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Aircraft - 20%
Astronomical - 25% I
Other - 13%
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Insufficient Info 1 7%
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Unknown 9% I
As the study of the current cases progressed, it became increasingly
obvious that if reporting and investigating procedures could be further improved, I
the percentages of those cases which contained insufficient information and
those remaining unexplained would be greatly reduced. The key to a higher
percentage of solutions appeared to be in rapid "on the spot" investigations
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by trained personnel. On the basis of this, a revised program was estab-
lished by AF Reg. 200-2 Subject: "Unidentified Flying Objects Reporting"
(Short Title: UFOB) dated 12 August 1954. I
This new program, which had begun to show marked results before
January 1955, provided primarily that the 4602d Air Intelligence Service'
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Squadron (Air Defense Command) would carry out all field investigations.
This squadron has sufficient units and is so deployed as to be able to arrive
"on the spot" within a very short time after a report is received. After
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treatment by the 4602d AISS, all information is supplied to the Air Technical
Intelligence Center for final evaluation. This cooperative program has re­
sulted, since 1 January 1955, in reducing the insufficient information cases
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to 7o/o and the unknown cases to 3%, of the totals.
The period l January 1955 to 5 May 1955 accounted for 131 unidentified
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aerial object reports received. Evaluation percentages of these are as follows:
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Balloons - 26%
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Aircraft - 21%
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I Astronomical - 23%
I Other 20%
Insufficient Info - 7%
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I Unknown - 3%
All available data were included in this study which was prepared by
I a panel of scientists both in and out of the Air Force. On the basis of this
study it is believed that all the unidentified aerial objects could have been
explained if more complete observational data had been available. Insofar
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as the reported aerial objects which still remain unexplained are concerned,
there exists little information other than the impressions and interpretations
of their observers. As these impressions and interpretations have been
I replaced by the use of improved methods of investigation and reporting, and
,by scientific analysis, the number of unexplained cases has decreased rapidly
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towards the vanishing point.
Therefore, on the b_asis of this evaluation of the information, it is
r· considered to be hi