Skip to content
UAP LEDGER
CIA

CIA-UAP-015: Project Blue Book Special Report No. 14 (Analysis of Reports of Unidentified Aerial Objects)

Released: June 12, 2026

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…

Full Document Text

Text extracted directly from the source PDF. Text extraction via abigailhaddad/ufo-releases; original file at war.gov.

Read the full text (200,000 characters)
--- PAGE 1 ---
----~.~ ..:_:._~,. /

          Approved fo..r: Release 2026 Under Section 1842 of the National Defen~5.e ,..,_      _ .,-<,y-; ~ -- --<-4H~
6 64 2250
FORM
                             1
 •        Authorizati6n Ac -e' for Fiscal Year 2024                       ~    5'f.J _:     ~- _,.,/
                                                                                1




                                          (PLACE FORM qgo HERE)




                           0 FFI C/IAL                             J




                           RECORD

                          The,
                          Agenc.
                          in accc.
                          additior,
                          Records

                                                   .,.----------


                       RETURN IMMEDIATELY AFTER USE TO THE
                        CIA ARCHIVES AND RECORDS CENTER

--- PAGE 2 ---
FORM
6-64
       2250




                               (PLACE FORM ~90 HERE}




                OFFICIAL                          J




                RECORD
                 COPY
                                     WARNING

               The attached document (s) must be safeguarded.   It is the
               Agency's Official Historical Record and must be preserved
               in accordance with the Federal Records Act of 1950.   For
               additional information, call the Chief, CIA Archives and
               Records Center, extension 2468.




              RETURN IMMEDIATELY AFTER USE TO THE
               CIA ARCHIVES AND RECORDS CENTER

--- PAGE 3 ---
,
         -:/).
I,._;· -C'.'.:'.:
           '
                    ,1/i
                       \
                               .. .        r   ..~..           ,=,. _._,_-
                                                               .-    _.," _ : . - - -   _J:
                                                                                              .
                                                                                              -~,,,,
                                                                                                             : ~ ~ ·,
                                                                                                        , -,_1: ...   -   ~-
                                                                                                                               ••,;-.,-·, C                                                                            /
                                                                                                                               ·~f·;•";,_,, ;: ~;..::;s.-..:.--:;_1-:,:,,•-'l(<..., - -... ~ · -....... --..._,,,!,.,,,,.,._
     ~              ~-                                                             I
                                                                                                       j/ )
                           'PROJECT BLLI ' B •
                  ?'e·--·('· ·~,--                                  ~~lt!L                                  ·•21u,c< ,.,.. #                                                   ·,               •                    .."""-

                                                                                                                                                                                                                1
 I                                                                                                                                                      d'"                    ;      ti?0
1---7                                                                               SJ
I '/~
I                                     SPECIAL REPORT N0.14
II




I                     (ANALYSIS OF REPORTS OF UNIDENTIFIED AERIAL OB1ECTS)

I
I                                               PROJECT NO. 10073

I
I                                                      5 MAY 1955

                                       \
I
I
I
I
.I
I              AIR TECHNICAL INTELLIGENCE CENTER
                                      WRIGHT-PATTERSON AIR FORCE BASE
I                                                  OHIO


I
                                                                                                                                                                                             35
I                                                                                                                              Copy No.
                                                                                                                                                                       --=----


,,




l

--- PAGE 4 ---
PROJECT BLUE BOOK


\I
'
                                    SPECIAL REPORT NO. 14


ii               (ANALYSIS OF REPORTS OF UNIDENTIFIED AERIAL OBJECTS)
1


il
            I
            I
            I                           PROJECT NO. 10073

            I
    :1                                        5 MAY 1955

    I
    1




    11
    !

    ii                               FOR OffIC!Al USt ONlY
                                               (AFR 190-16)
     I
    :I
    !1  I
        I

                         AIR TECHNICAL INTELLIGENCE GENTER
            I             WRIGHT-PATTERSON AIR FORCE BASE
                                                  o:mo

            I
            I               No copyright materiel ls contained In this publication,


            _I

--- PAGE 5 ---
I
I                                                    TABLE OF CONTENTS


I   SUMMARY.                                                                                   vii


I   INTRODUCTION

    ORIGIN AND NATURE OF DATA                                                                    3


I   REDUCTION OF DATA TO MECHANIZED COMPUTATION FORM

         Questionnaire .
                                                                                                 4

                                                                                                 4
         Coding System and Work Sheet                                                            6

I        Identification of Working Papers.
         Evaluation of Individual Reports
                                                                                                7
                                                                                               10

    ANALYSIS OF THE DATA.                                                                      14

I        Frequency and Percentage Distributions by Characteristics
              Graphical Presentation .
                                                                                               14
                                                                                               16
         Advanced Study of the Data                                                            16

I             Position of the Sun Relative to the Observer
              Statistical Chi Square Test
         The "Flying Saucer" Model
                                                                                               16
                                                                                               60
                                                                                               76


I   CONCLUSIONS

    APPENDIX A. TABULATION OF FREQUENCY AND PERCENTAGE
     DISTRIBUTIONS BY CHARACTERISTICS
                                                                                               94


                                                                                                95


I   APPENDIX B.     WORKING PAPER FORMS

                                                   LIST OF ILLUSTRATIONS
                                                                                               255




I   Figure l

    Figure 2
               Frequency of Sightings by Year for Object, Unit, and All Sightings

               Distribution of Evaluations of Object, Unit, and All Sightings for All Years
                                                                                                17

                                                                                                18


I   Figure 3   Distribution of Object Sightings by Evaluation for All Years With Comparisons
                of Each Year for Each Evaluation Group •                                        19



I   Figure 4

    Figure 5
               Distribution of Object Sightings by Evaluation for All Years and Each Year

               Distribution of Object Sightings by Evaluation Within Months for All Years
                                                                                                20

                                                                                                21



I
    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
                Months, 1947-1952.                                                              23

I   Figure 8   Distribution of Object Sightings by Sighting Reliability Groups With
                Evaluation Distributions for Each Group .                                       24



I   Figure 9   Distribution of Object Sightings Among the Four Sighting Reliability
                Groups for All Years and Each Year .

    Figure 10 Distribution of All Sightings by Sighting Reliability Groups, Segregated
                                                                                                25




I              by Military and Civilian Observers, With Evaluation Distribution
               for Each Segregation

    Figure 11 Distribution of Object Sightings by Reported Colors of Object(s) With
                                                                                                26




I              Evaluation Distribution for Each Color Group •

    Figure 12 Distribution of Object Sightings by Number of Objects Seen per Sighting
               With Evaluation Distribution for Each Group
                                                                                                27


                                                                                                28


I   Figure 13 Distribution of Object Sightings by Duration of Sighting With Evaluation
               Distribution for Each Duration Group .                                           29



I
I                                                             iii


I

--- PAGE 6 ---
I
                                               LIST OF ILLUSTRATIONS
                                                                                                    I
                                                                                                    I
                                                     (Continued)

                                                                                             Page



                                                                                                    I
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

Figure 16 Distribution of Object Sightings by Reported Speed of Object(s) With
           Evaluation Distribution for Each Speed Group .                                     32
                                                                                                    I
Figure 17 Distribution of All Sightings by Observer Location for All Years and Each Year

Figure 18 Comparison of Known and Unknown Object Sightings by Color, 1947-1952
                                                                                              33

                                                                                              34
                                                                                                    I
Figure 19 Comparison of Known and Unknown Object Sightings by Number of Objects
           per Sighting, 1947-1952                                                            35    I
Figure 20 Comparison of Known and Unknown Object Sightings by Speed, 1947-1952                36

Figure 21 Comparison of Known and Unknown Object Sightings by Duration, 1947-1952

Figure 22 Comparison of Known and Unknown Object Sightings by Shape, 1947-1952
                                                                                              37

                                                                                              38
                                                                                                    I
Figure 23 Comparison of Known and Unknown Object Sightings by Light Brightness, 1947-1952

Figure 24 Comparison of Monthly Distribution of Object Sightings Evaluated as Astronomical
                                                                                              39
                                                                                                    I
           Versus Total Object Sightings Less Astronomical.

Figure 25 Comparison of Monthly Distribution of Object Sightings Evaluated as Aircraft
           Versus Total Object Sightings Less Aircraft
                                                                                              40


                                                                                              41
                                                                                                    I
Figure 26 Comparison of Monthly Distribution of Object Sightings Evaluated as Balloon
           Versus Total Object Sightings Less Balloon,                                        42    I
                                                                                                    I
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

Figure 29 Comparison of Monthly Distribution of Object Sightings Evaluated as Unknown
           Versus Total Object Sightings Less Unknown                                         45
                                                                                                    I
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
             Subdivisions of One Degree of Latitude and Longitude

Figure 32 Distribution of Object Sightings by Evaluation for the Twelve Regional Areas of
           the U. S., With the Strategic Areas Located
                                                                                              47
                                                                                                    I
                                                                                              48

Figure 33 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
           Central East Region                                                                49
                                                                                                    I
Figure 34 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
           Central Midwest Region

Figure 35 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
                                                                                              50
                                                                                                    I
                                                                                                    I
           Central Farwest Region                                                             51

Figure 36 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
           South Midwest Region .                                                             52

Figure 37 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
           South West Region                                                                  53
                                                                                                    I
                                                                                                    I
                                                          iv
                                                                                                    I
                                                                                                    I

--- PAGE 7 ---
I
I
I                                                 LIST OF ILLUSTRATIONS
                                                        (Continued)




I   Figure 38 Comparison of Evaluation of Object Sightings in the Strategic Areas of the
               South Farwest Region .                                                                54



I   Figure 39 Diagram of a Celestial Sphere.

    Figure 40 Frequency of Object Sightings by Angle of Elevation of the Sun, Intervals
               of 10 Degrees of Angle.
                                                                                                     56


                                                                                                     57


I   Figure 41 Frequency of Object Sightings by Local Sun Time, Intervals of One Hour

    Table      Object Sightings
                                                                                                     59

                                                                                                     60


I   Table

    Table
            II Chi Square Test of Knowns Versus Unknowns on the Basis of Color

            III Chi Square Test of Knowns Versus Unknowns on the Basis of Number
                                                                                                     62

                                                                                                     63


I   Table

    Table
            IV Chi Square Test of Knowns Versus Unknowns on the Basis of Shape

            V Chi Square Test of Knowns Versus Unknowns on the Basis of Duration of Observation
                                                                                                     64

                                                                                                     65


I   Table   VI Chi Square Test of Knowns Versus Unknowns on the Basis of Speed

    Table VII Chi Square Test of Knowns Versus Unknowns on the Basis of Light Brightness
                                                                                                     ti6

                                                                                                     67


I   Table VIII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Color

    Table   IX Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Number.
                                                                                                     70

                                                                                                     71



I   Table

    Table
            X Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Shape

            XI Chi Square Test of Revised Knowns Versus Unknowns on the Basis of
                Duration of Ob~ervation
                                                                                                     72


                                                                                                     73


I   Table XII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Speed

    Table XIII Chi Square Test of Revised Knowns Versus Unknowns on the Basis of Light Brightness.
                                                                                                     74

                                                                                                     75


I
I
I
I
I
I
I
I
I                                                        v and vi

I

--- PAGE 8 ---
I
 I                                     SUMMARY


 I           Reports of unidentified aerial objects (popularly termed "flying
     saucers" or "flying discs") have been received by the U.S. Air Force

 I   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

 I   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.

 I           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

I    attempt to maintain complete objectivity and consistency.

             Analysis of the refined and evaluated data derived from the original

I    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

I    to determine the probability that any of the UNKNOWNS represent observa.:.
     tions of technological' developments not known to this country.


I             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

I    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

I    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.

I            The special study which resulted in this report (Analysis of Reports
     of Unidentified Aerial Objects, 5 May 1955) started in 1953. To provide the

I    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

I
                                           vii
!I




I

--- PAGE 9 ---
I
with the year 1952.   In these charts, 3201 cases have been used.
                                                                                    I
        As the study progressed, a constant program was maintained for              I
the purpose of making comparisons between the current cases received
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                I
current developments could be incorporated in the summary of this report.

         The 1953 and 1954 cases show a general and expected trend of               I
increasing percentages in the finally identified categories. They also.show
decreasing percentages in categories where there was insufficient informa­
tion and those where the phenomena could not be explained. This trend had           I
been:. anticipated in the light of improved reporting and investigating pro­
ceduJ;"es.
                                                                                    I
        Official reports on hand at the end of 1954 totaled 4834. Of these,
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           I
those received before the end of 1952. The results are as follows:

                       Balloons            - 16%                                    I
                       Aircraft            - 20%
                                                                                    I
                       Astronomical        - 25%

                       Other               - 13%                                    I
                       Insufficient Info      1 7%
                                                                                    1.
                       Unknown             - 9%
        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           I
percentage of solutions appeared to be in rapid "on the spot" investigations
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'
                                                                                    I
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
                                                                                    I
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
                                                                                    I
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
                                                                                    I
aerial object reports received. Evaluation percentages of these are as follows:
                                                                                    I
                                       viii
                                                                                    I
                                                                                    I

--- PAGE 10 ---
I
-
    I        I                          Balloons            - 26%

    I
.....
                                       Aircraft

                                       Astronomical
                                                            - 21%

                                                            - 23%
    I                                   Other                   20%

I   ,,
                                        Insufficient Info -

                                       Unknown              -
                                                                7%

                                                                3%
    I                     All available data were included in this study which was prepared by
                  a panel of scientists both in and out of the Air Force. On the basis of this
I       fi
                  study it is believed that all the unidentified aerial objects could have been
                  explained if more complete observational data had been available. Insofar
                  as the reported aerial objects which still remain unexplained are concerned,
I                 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


I
                  towards the vanishing point.

                         Therefore, on the b_asis of this evaluation of the information, it is
    r·           considered to be highly improbable that reports of unidentified aerial objects
                 examined in this study represent observations of technological developments
I                outside of the range of present-day scientific knowledge. It is emphasized
                 that there has been a complete lack of any valid evidence of physical 'matter

I       [1
                 in any case of a reported unidentified aerial object.



I   '

I
I   '

I   f


I
I
I
I
I                                                      ix

--- PAGE 11 ---
I
I                                              INTRODUCTION

I          In June, 1947, Kenneth Arnold, a Boise, Idaho, businessman and

I    private pilot, publicly reported the now-famous sighting of a chainlike
     formation of disc-shaped objects near Mount Rainier, Washington. Result­
     ing newspaper publicity of this incident caught the public interest, and,
I    shortly thereafter, a rash of reports of unidentified aerial objects spawned
     the term "flying saucers". During the years since 1947, many reports of

I    unidentified aerial objects have been received by the Air Force from many
     and diverse sources.


I          The unfortunate term "flying saucer", or "flying disc", because of
     its widespread and indiscriminate use, requires definition. Many defini­

I    tions have been offered, one of the best being that originated by Dr. J.
     Allen Hynek, Director of the Emerson McMillin Observatory of The Ohio
     State University, who has taken a scientific interest in_the problem of

I    unidentified aerial objects since 1949. Dr. Hynek' s definition of the term
     is "any aerial phenomenon or sighting that remains unexplained to the
     viewer at least long enough for him to write a report about it 11 ( 1). Dr. Hynek,
·1   elaborating on his definition, says, "Each flying saucer, so defined, has
     associated with it a probable lifetime. It wanders in the field of public in­
     spection like an electron in a field of ions, until I captured' by an explana­
I    tion which puts an end to its existence as a I flying saucer' 11 ( 1).


I          This definition would be applicable to any and all of the sightings
     which remained unidentified throughout this study. However, the term
     "flying saucers" shall be used hereafter in this report to mean a novel,
I    airborne phenomenon, a manifestation that is not a part of or readily ex­
     plainable by the fund of scientific knowledge known to be possessed by the

I    Free World. This would include such items as natural phenomena that are
     not yet completely understood, psychological phenomena, or intruder air­
     craft of a type that may be possessed by some source in large enough

I    numbers so that more than one independent mission may have been flown
     and reported. Thus, these phenomena are of the type which should have
     been observed and reported more than once.
I          Since 1947, public interest in the subject of unidentified aerial objects

I    fluctuated more or less within reasonable limits until the summer of 1952,
     when the frequency of reports of sightings reached a peak, possibly stimu­
     lated by several articles on the subject in leading popular magazines.
I          Early in 1952, the Air Force's cumulative study and analysis of
     reported sightings indicated that the majority of reports could be accounted
I    for as misinterpretations of known objects ( such as meteors, balloons, or
     aircraft), a few as the result of mild hysteria, and a very few as the result

I    of unfamiliar meteorological phenomena and light aberrations. However,
     (1) Hynek, J. A.• "Unusual Aerial Phenomena"• Journal of the Optical Society of America. 43 (4).

I        pp 311-314, April, 1953.

                                                         1


J

--- PAGE 12 ---
I
a significant number of fairly complete reports by reliable observers re­        I
mained unexplained. Although no evidence existed that unexplained reports
of sightings constituted_ a 1>hysical threat to the security of the U. S., in
March, 1952, the Air Force decided that all reports of unidentified
                                                                                 I
aerial objects should be investigated and evaluated to determine if "flying
saucers" represented technological developments not known to this country.       I
      Originally, the problem involved the preparation and analysis of about
1,300 reports accumulated by the Air Force between 1947 and the end of
                                                                                 I
March, 1952. During the course of the work, the number of reports sub­
mitted for analysis and evaluation more than tripled, the result of the un­
precedented increase in observations during 1952. Accordingly, this study
                                                                                 I
is based on a number of reports considered to be large enough for a pre­
liminary statistical analysis, approximately 4, 000 reports.                     I
       This study was undertaken primarily to categorize the available
reports of sightings and to determine the probability that any of the reports
                                                                                 I
of unidentified aerial objects represented observations of "flying saucers".
With full cognizance of the quality of the data available for study, yet with
an awareness of the proportions this subject has assumed at times in the
                                                                                 I
public mind, this work was undertaken with all the seriousness accorded
to a straightforward scientific investigation. In order to establish the         I
probability that any of the reports of unidentified aerial objects represented
observations of "flying saucers", it was necessary to make an attempt to
answer the question "What is a 'flying saucer'?". However, it must be
                                                                                 I
emphasized that this was only incidental to the primary purpose of the
study, the determination of the probability that any of the reports of un­
identified aerial objects represented observations of "flying saucers", as
                                                                                 I
defined on Page 1.
                                                                                 I
      The basic technique for this study consisted of reducing the available
data to a form suitable for mechanical manipulation, a prerequisite for the
application of preliminary statistical methods .. One of International
                                                                                 I
Business Machine Corporation's systems was chosen as the best available
mechanical equipment.                                                            I
      The reduction of data contained in sighting reports into a form suit­
able for transfer to IBM punched cards was extremely difficult and time
                                                                                 I
consuming.

      For this study a panel of consultants was formed, consisting of both
                                                                                 I
experts within and outside A TIC. During the course of the work, guidance
and advice were received from the panel. The professional experience             I
available from the panel covered major scientific fields and numerous
specialized fields.
                                                                                 I
     All records and working papers of this study have been carefully
preserved in an orderly fashion suitable for ready reference. These              I
                                      2                                          I
                                                                                 l

--- PAGE 13 ---
I
I   records include condensations of all individual sighting reports, and the
    IBM cards used in various phases of the study.
I
I                         ORIGIN AND NATURE OF DA TA


I         Reports of sightings were received by the U. S. Air Force from a
    representative cross section of the population of the U. S., and varied
I   widely in completeness and quality. Included were reports from reputable
    scientists, housewives, farmers, students, and technically trained mem­

I   bers of the Armed Forces. Reports varied in length from a few sentences
    stating that a "flying saucer" had been sighted, to those containing thou­
    sands of words, including description, speculation, and advice on how to

I   handle the "problem of the I flying saucers 1 " . Some reports were of high
    quality, conservative, and as complete as the observer could make them;
    a few originated from people confined to mental institutions. A critical
I   examination of the reports revealed, however, that a high percentage of
    them was submitted by serious people, mystified by what they had seen and

I   motivated by patriotic responsibility.

          Three principal sources of reports were noted in the preliminary
I   review of the data. The bulk of the data arrived at A TIC through regular
    military channels, from June, 1947, until the middle of 1952.

I          A second type of data consisted of letters reporting sightings sent by
    civilian observers directly to A TIC. Most of these direct communications

I   were dated subsequent to April 30, 1952, and are believed to be the result
    of a suggestion by a popular magazine that future reports be directed to the
    Air Technical Intelligence Center. As could be expected, a large number
I   of letters was received following this publicity.


I         A third type of data was that contained in questionnaire forms com­
    pleted by the observer himself. A questionnaire form, developed during
    the course of this study, was mailed by A TIC to a selected group of writers

I   of direct letters with the request that the form be completed and returned.
    Approximately 1,000 responses were received by ATIC.

I           In general, the data were subjective, consisting of qualified estimates
    of physical characteristics rather than of precise measurements. Further­

I   more, most of the reports were not reduced to written form immediately.
    The time between sighting and report varied from one day to several years.
    Both of these factors introduced an element of doubt concerning the validity
I   o,f the original data, and increased its subjectivity. This was intensified by
    the recognized inability of the average individual to estimate speeds, dis­
    tances, and sizes of objects in the air with any degree of accuracy. In
I   spite of these limitations, methods of statistical analysis of such reports m
    sufficiently large groups are valid. The danger lies in the possibility of

I                                         3


I

--- PAGE 14 ---
I
forgetting the subjectivity of the data at the time that conclusions are
drawn from the analysis. It must be emphasized, again and again, that any
                                                                                                                 I
conclusions contained in this report are based NOT on facts, but on what
many observers thought and estimated the true facts to be.
                                                                                                                 I
       Altogether, the data for this study consisted of approximately 4, 000
 reports of sightings of unidentified aerial objects. The majority were :re­
                                                                                                                 I
 ceived through military channels or in the form of observer-completed
 questionnaires; a few were accepted in the form of direct letters from un­                                      I
-questionably reliable sources. Sightings made between June, 1947, and
 December, 1952, were considered for this study. Sightings alleged to have
 occurred prior to 1947 were not considered, since they were not reported
                                                                                                                 I
 to official sources until after public interest in "flying saucers" had been
 stimulated by the popular press.                                                                                I
                                                                                                                 I
       REDUCTION OF DA TA TO MECHANIZED COMPUTATION FORM
                                                                                                                 I
      As received by the Air Technical Intelligence Center, the sighting
reports were not in a form suitable for even a quasi-scientific study. A
preliminary review of the data indicated the need for standardized interro­
                                                                                                                 I
gation procedures and supplemental forms for the reduction of currently
held and subsequently acquired data to a form amenable to scientific
                                                                                                                 I
appraisal.

       The plan for reduction of the data to usable form consisted of a pro­
                                                                                                                 I
gram of development comprising four major steps: ( 1) a systematic listing
of the factors necessary to evaluate the observer and his report, and to                                         I
identify the unknown object observed; (2) a standard scheme for the trans­
fer of data to a mechanized computation system; (3) an orderly means of
relating the original data to_ all subsequent forms; and ( 4} a consistent pro­
                                                                                                                 I
cedure for the identification of the phenomenon described by the original
data.                                                                                                            I
                                            Questionnaire                                                        I
      The first reports received by A TIC varied widely in completeness
                                                                                                    I
                                                                                                                 I
and quality. Air Force Letter 200-5(2} and Air Force Form 112( 1) were
attempts to fix responsibility for and improve the quality of the reports of                                     I
sightings. To coordinate past efforts and to provide standardization for the

(1) A modified Air Force Form 112 lists pertinent questions to be answered in regard to an unidentified-object   I
    sighting.
(2) Air Force Letter 200-5 places responsibility with the Air Force for the investigation, reporting, and
    analysis of unidentified aerial objects. This letter is dated 29 April 1952.                                 I
                                                      4                                                          I
                                                                                                                 I

--- PAGE 15 ---
I
I   future, it was imperative to develop a questionnaire form listing the factors
    necessary for evaluation of the observer and his report, and identification
I   of the unknown objects. In addition, it was decided that such a questionnaire
    should be designed to serve as an interrogator's guide, and as a form for

I   the observer himself to complete when personal interrogation was not possi­
    ble or practicable.

I          Ideally, a questionnaire for the purposes required should contain
    questions pertaining to all technical details considered to be essential for

I   the statistical approach, and should serve to obtain a maximum of informa­
    tion from the average individual who had made a sighting in the past or
    would be likely to be reporting sightings in the future. Besides these ~is­

I   crete facts, an integrated written description of a sighting would be re­
    quired, thus enabling the reported facts of the sighting to be corroborated.
    Also, a narrative description might allow subtle questions to be answered
I   concerning the observer's ability, such as indirect questions that would
    reveal his reasoning ability, suggestibility, and general mental attitude.

I   As a whole, then, the information contained in a questionnaire should make
    possible the classification and evaluation of the sighting, the rating of the
    observer, the probability of accuracy of reported facts, and the identifica­
I   tion of what was reported by the observer as unidentified.

          During the course of this project, three questionnaire forms were
I   developed, each intended to be an improved revision of the one preceding.
    The improvements were suggested and confirmed by members of the panel

I   of consultants connected with this project.

           The original form was evolved by the panel of consultants as their
I   first work on this project. It was intended to allow the start of the reduc­
    tion of reports to discrete data, and was immediately subjected to exten­

I   sive review and revision by the panel. The revised ( second) form was
    subjected to a trial test before adoption. A TIC sent a copy to observers
    reporting sightings, with the request that the form be completed and re­

I   turned. Of the first 300 questionnaires returned during July and August,
    1952, 168 were analyzed by a consulting psychologist. On the basis of this
    analysis, plus the experience gained in working with past reports, the final
I   form of the questionnaire - the U. S. Air Force Technical Information
    Sheet - was evolved. Copies of the three forms of the questionnaire, in

I   the order of their development, are shown as Exhibits BI, B2, and B3 in
    Appendix B.


I         In order to implement the transcription of data from past sighting
    reports, each succeeding form was put to use as soon as it was developed
    and approved. Accordingly, experience was obtained with each form in
I   relation to past data, an important factor in the improvement of the quality
    and completeness of the later reports included in this study.

I
I                                        5

I

--- PAGE 16 ---
I
                       Coding System and Work Sheet                            I
       The reduction of non-numerical data to numerical form is mandatory
                                                                               I
in the machine handling of data. Thus, the selection of the IBM punched­
card system for analysis of data forced the adoption of a master coding
plan. Since it was impracticable to transfer detailed data of a~ exact
                                                                               I
nature from the questionnaire to the IBM card, an intermediate transfer
form, coordinated with the master code, was necessary.                         I
       The master coding plan was evolved during the early stages of the
preli~inary analysis of data, and was reviewed by the panel of consultants
                                                                               I
before use. It was recognized that this system of coding would be the
heart of the analysis, that is, the completeness of the facility for trans­
lation of data could make or break the study. Accordingly, every conceiv­
                                                                               I
able factor that might influence the identification of unidentified aerial
objects was included, together with a wide range of variations within each
                                                                               I
factor. The original coding system (with minor corrections) was used
throughout the translation of the original data with marked success. A copy
of this system, called CODES, is enclosed as Exhibit IH, Appendix B.
                                                                               I
      To facilitate the preparation of the punched-card abstract, an inter­    I
mediate form called the WORK SHEET (later, the CARD BIBLE) was
developed. Referenced to both the data from the questionnaire and the sys­
tem of report identification, the WORK SHEET permitted an orderly
                                                                               I
transcription of data simultaneously by several people. In conjunction
with the CODES, the WORK SHEET was used during the reduction of the
original data to code form necessary for transfer to punched cards. A
                                                                               I
sample is included as Exhibit BS, Appendix B.
                                                                               I
      After the analysis was under way, it became apparent that the me­
chanics of machine processing could be improved by incorporating in the
IBM card system group classifications of certain factors requiring more
                                                                               I
than one column for discrete expression. In addition, the inclusion of
certain data relating to the evaluation and bearing of the sun with respect
to the observer was considered necessary. Finally, a critical examination
                                                                               I
of certain segments of the data indicated the need for the definition of a
new factor relating to the maneuvers of the object or objects sighted.
                                                                               I
Prior to the start of the analytical study, it had been assumed that a com­
bination of stated factors would, by inference, define the maneuver pattern.   I
      All these additions have been incorporated in a revised set of CODES
and CARD BIBLE that are illustrated as Exhibits B6 and B7, Appendix B.         I
However, at the time that the maneuver factor was determined to be criti­
cal, it was physically impracticable to make the required definitions and
re-evaluate the original data. Therefore, no code for maneuverability has
                                                                               I
been included in the CODES, CARD BIBLE, or IBM cards.
                                                                               I
                                     6                                         I
                                                                               I

--- PAGE 17 ---
I
I                         Identification of Working Papers


I         The actual reduction of data to IBM punched-card form presented a

I   problem of mass transfer of figures by several workers. Recognizing that
    an orderly system of relating the original data to the questionnaire, the
    WORK SHEET, and the IBM card was imperative, a scheme of SERIAL

I   NUMBERS was developed to answer this need.

           The first data consisted of a series of letter-file folders identified by
I   the year and location of the sighting or sightings they contained. The num­
    ber of reports of sightings in a single folder varied from 1 to over 20.

I   Under these conditions, there was a great possibility for incorrect tran­
    scription of data, duplication of transcription, or misplacement of inter­
    mediate forms. Further, it was considered desirable to relate all sightings

I   of the same object or objects to one another. The concept of a four-digit
    serial number (major), followed by a two-digit subserial number (minor),
    was adequate to fulfill these requirements.
I          To expedite handling of the data, temporary serial numbers were

I   assigned until each report had been evaluated and the phenomenon had been
    placed i11:, a category of identification. The use of temporary serial num­
    bers permitted the consolidation of duplicate reports from apparently
I   diverse sources, such as a teletype message and an Air Force Form 112.
    However, this consolidation was made ONLY when it could be proved con­

I   clusively that the sources of the two documents were one and the same.
    Factors of the observer's location, date and time of observation, descrip­
    tion of the phenomenon, and finally, the name of the observer were con­

I   sidered. In this manner, the assignment of major serial and minor sub­
    serial numbers in continuous series was made only to the reports accepted
    for the statistical study. It is believed that the reports accepted represent
I   unique and unduplicated instances of sightings.


I         In the establishment of the serial-number system, it was necessary
    to define certain terms,' so that a standard interpretation could be achieved.
    The terms and corresponding definitions were:
I         OBSERVER - Any witness reporting to a proper authority that
                     he had seen unidentified aerial objects.
I         SIGHTING       The report or group of reports of the same

I                        observed phenomenon that remained unidenti­
                         fied to the observer or observers, at least
                         until reported.
I
I
I                                          7


I

--- PAGE 18 ---
I
      SINGLE OBSERVATION - A SIGHTING consisting of a single                   I
                 report from ( 1) one OBSERVER with no knowledge
                 of additional OBSERVERS of the same phenom­
                 enon, or (2) a group of witnesses of the same
                                                                               I
                 phenomenon, each cognizant of the others. The
                 witness who made the report is called a SINGLE
                 OBSERVER.
                                                                               I
      MULTIPLE OBSERVATION - A SIGHTING consisting of                          I
                 several reports from OBSERVERS of the same
                 phenomenon who were cognizant of each other.
                 The witnesses who made reports are called
                                                                               I
                MULTIPLE OBSERVERS.
                                                                               I
      ALL SIGHTINGS - ( 1) The group of reports consisting of one
                  report for each OBSERVER, including both
                  SINGLE and MULTIPLE OBSERVERS. (2) The
                                                                               I
                  questionnaire, work sheet, and IBM card
                  representing the report from each OBSERVER -
                  in other words, the representation of each report
                                                                               I
                  accepted for the statistical study.
                                                                               I
      UNIT SIGHTINGS - ( 1) The group of reports consisting of one
                  report for each SIGHTING, including all the
                  reports of SINGLE OBSERVATIONS and the one
                                                                               I
                  most representative report from each MULTIPLE
                  OBSERVATION. (2) The questionnaire, work
                  sheet, and IBM card representing the report for
                                                                               I
                  each SIGHTING accepted for the statistical study.
                                                                               I
      A major serial number (four digits) was assigned to each sighting,
segregating the year of occurrence by selection of limits for each year, as
follows:
                                                                               I
                      0001 to 0500 reserved for 1947
                      0501 to 1000 reserved for 1948
                                                                               I
                      1001 to 1500 reserved for 1949
                      150lto2000 reserved for 1950
                                                                               I
                      2001 to 2500 reserved for 1951
                      2501 to4900 reserved for 1952                            I
While this scheme would serve to identify any individual sighting, identifi­
cation of each report and its subsequent forms was necessary. The minor        I
subserial numbers ( two digits) fulfiiled this requirement. For all SINGLE
OBSERVATIONS, a major serial number followed by two (2) zeros, for
example, 2759. 00, was sufficient identification. For MULTIPLE OBSER­
                                                                               I
VATIONS, the major serial number followed by a series of two-digit num­
bers ranging from 00 to 99 was used to identify the individual reports. In
general, the most complete report from the most reliable observer of that
                                                                               I
                                      8                                        I
                                                                               I

--- PAGE 19 ---
I
I   MULTIPLE OBSERVATION was identified with the . 00 subserial number.
    As an example, a MULTIPLE OBSERVATION consisting of six sighting
I   reports would have the following serial numbers:



I                1132. 00 representing the best report and observer
                 1132.01 representing an additional observer
                 1132. 02 representing an additional observer

I                1132. 03 representing an additional observer
                 1132. 04 representing an additional observer
                 1132. 05 representing an additional observer
I         During the course of the transcription of the data to machine card

I   form, it became obvious that certain reports could have been independent
    observations of the same phenomenon. So, if the presentation of an
    analysis based on one report for each sighting was valid ( the concept of

I   UNIT SIGHTINGS}, a presentation of an analysis based on one report for
    each phenomenon should be valid also. Further, the examination of data
    relating to the actual number of phenomena was considered to be the proper
I   basis for assessing the probability of technological developments outside
    the range of present-day scientific knowledge. Therefore, a designation of

I   OBJECT SIGHTINGS was established, with the following definition:

          OBJECT SIGHTING - ( 1) The group of reports consisting of
I                    one report for each phenomenon. (2) The
                     questionnaire, work sheet, and IBM card

I                    representing a report for each phenomenon
                     accepted for the statistical study.


I   In brief review, ALL SIGHTINGS refer to all reports, UNIT SIGHTINGS
    refer to actual sightings, and OBJECT SIGHTINGS refer to the assumed
    number of phenomena.
I         It must be recognized that the process of identifying OBJECT

I   SIGHTINGS was deductive, while that for UNIT SIGHTINGS was definitive.
    A conservative approach was adopted in the determination of OBJECT
    SIGHTINGS, using the factors of date and time of observations, location
I   of observers, duration of observations, and range, bearing, track direc­
    tion, and identification of the phenomena. Any error of selection of OBJECT
    SIGHTINGS will tend to be in the direction of reducing the actual number of
I   phenomena observed ( several instances of UNIT SIGHTINGS that might be
    one OBJECT SIGHTING were noted, but the evidence was not conclusive

I   enough to justify consolidation of the reports).

          Following the determination of OBJECT SIGHTINGS, a series of
I   serial numbers, called the INCIDENT SERIAL NUMBERS, was established
    to facilitate any future study of a specific object sighting. Each reported

I   sighting that relates to an OBJECT SIGHTING received the same incident
    serial number, a four-digit code paralleling the major serial number
    series.

I                                        9

I

--- PAGE 20 ---
I
       For machine manipulation, it was desirable to be able to select the        I
sample of cards (all reports, all sightings, or all phenomena) to be in­
cluded in a particular study. The concept of a SIGHTING IDENTIFICATION
NUMBER was evolved to fill this desire. Using one column of the IBM
                                                                                  I
card, and the correlated working papers,· the code for this function was
developed. Multiple punching eliminated the need to use several columns
for discrete expression of the variations. Selection of the proper number
                                                                                  I
in this column thus permitted selection of the desired sample of cards.         ·1
                      Evaluation of Individual Reports                           I
      Evaluation of sighting reports was recognized as a crucial step in the
preparation of data for statistical treatment; inconsistent evaluations would
                                                                                 I
have invalidated any conclusions to be derived from this study. A method
of evaluation was, therefore, determined simultaneously with the develop­
                                                                                 I
ment of the questionnaire, the coding system, and the work sheet. It is
emphasized that all phases of evaluation, even including the tedious prep­
aration of the original data for statistical treatment, were entrusted only
                                                                                 I
to selected, specially qualified scientists and engineers.
                                                                                 I
        Evaluation consisted of a standardized procedure to be followed for:
( 1) the deduction of discrete facts from data which depended on human im­
pressions rather than scientific measurements, (2) the rating of the ob­
                                                                                 I
server and his report as determined from available information, and ( 3) the
determination of the probable identification of the phenomenon observed.
Categories of identification, established upon the basis of previous experi­
                                                                                 I
ence, were as follows:
                                                                                 I
                       Balloon
                       Astronomical
                       Aircraft
                                                                                 I
                       Light phenomenon
                       Birds
                       Clouds, dust, etc.
                                                                                 I
                       Insufficient information
                       Psychological manifestations
                                                                                 I
                       Unknown
                       Other                                                     I
       The first step in evaluation, the deduction of discrete facts from
subjective data, required certain calculations based on the information          I
available in the sighting report. An example was the finding of the approxi­
mate angular velocity and acceleration of the object or objects sighted.
Care was taken during this phase of the work to insure against the deduc­
                                                                                 I
tion of discrete facts not warranted by the original data. Thus, even
though there was a complete lack of any valid evidence consisting of            I
                                     10                                          I
                                                                                 I

--- PAGE 21 ---
I
I    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
I    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
1·   reports of sightings were eliminated or rejected in this manner. Most of
     these reports were rejected because they were extremely nebulous; the

I    rest were rejected because they contained highly conflicting statements.

           The second step in evaluation, the rating of the observer and his

I    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:
I          ( 1)   The experience of the observer, deduced from his

I          ( 2)
                  occupation, age, and training;

                  The consistency among the separate portions of the

I                 description of the sighting;

           (3)    The general quality and completeness of the report;
I          (4)    Consideration of the observer's fact-reporting ability

I                 and attitude, as disclosed by his manner of describing
                  the sighting.


I    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

I    the statistical study.

            The third step in the process of evaluation, the attempted identifica­

I    tion of the object or objects sighted, was done twice, first 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
I    sentatives from ATIC and two from the panel of consultants. Although
     representatives of A TIC participated in making the final identifications, it

I    must be emphasized that any previous identification of a sighting made by
     A TIC was not introduced or referred to in any way.


I          In the coding system, the choices provided for final identifications
     were based on A TIC' s previous experience in analysis of the data. They
     had found that the majority of sightings could be classified as misinterpre­
I    tations of common objects or natural phenomena. Accordingly, categories
     for objects most frequently present in the air were provided. Balloons,

I    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
I                                           11

I

--- PAGE 22 ---
I
meteorological phenomena like small tornadoes, were collected into a
category called OTHER. A separate category for the uncommon natural
                                                                                I
phenomena associated with light reflections or refractions, such as mirages,
sun dogs, inversion-layer images, and distortions caused by airborne ic.e,
                                                                                I
was established with the title of LIGHT PHENOMENON. Categories for
INSUFFICIENT INFORMATION, PSYCHOLOGICAL MANIFESTATIONS, and
UNKNOWN were provided for the sightings that could not be fitted into the
                                                                                I
preceding identifications. An explanation of their use follows:
                                                                                I
      INSUFFICIENT INFORMATION - This identification category
                   was assigned to a report when, upon final con­
                   sideration, there was some essential item of
                                                                                I
                   information missing, or there was enough
                   doubt abou._t what data were available to disallow
                 • identification as a common object or some
                                                                                I
                   natural phenomenon. It is emphasized that this
                   category of identification was not used as a
                                                                               I
                   convenient way to dispose of what might be
                   called "poor unknowns", but as a category for
                   reports that, perhaps, could have been one of
                                                                               I
                   several known objects or natural phenomena.
                  No reports identified as INSUFFICIENT INFORMA­
                   TION contain authenticated facts or impressions
                                                                               I
                   concerning the sighting that would prevent its
                   being identified as a known object or phenomenon;
                                                                               I
     PSYCHOLOGICAL MANIFESTATIONS - This identification
                category was assigned to a report when,
                                                                               I
                although it was well established that the ob­
                server had seen something, it was also                         I
                obvious that the description of the sighting
                had been overdrawn. Religious fanaticism, a
                desire for publicity, or an over-active imagi­
                                                                               I
                nation were the most common mental aber­
                rations causing this type of report;                           I
     UNKNOWN - This designation in the identification code was
                assigned to those reports of sightings wherein                 I
                the description of the object and its maneuvers
                could not be fitted to the pattern of any known
                object or phenomenon.
                                                                               I
     For the purposes of this study, two groups of identifications were
recognized, the KNOWNS (including all identification categories except the
                                                                               I
UNKNOWNS) and the UNKNOWNS.
                                                                               I
      All possible identifications provided in the code system, except
INSUFFICIENT INFORMATION and UNKNOWN, could be assigned accord­
ing to two degrees of certainty, designated "Certain" and "Doubtful".
                                                                               I
                                    12                                         I
                                                                               I

--- PAGE 23 ---
I
I   A "Certain" identification indicated a minimum amount of doubt regarding
    the validity of the evaluation. By "rule-of-thumb" reasoning, the proba­
I   bility of the identification being correct was better than 95 per cent. A
    "Doubtful'' identification indicated that the choice was less positive, but

I   that there was a better than even chance of being correct.

           It is emphasized again that, as was tr.ue for other phases of evalua­
I   tion, preliminary and final identification was entrusted only to scientists
    and engineers who, in addition to their broad scientific background, had

I   received instruction, where necessary, in specialized subjects. The panel
    of consultants provided background information for this instruction. Many
    of the cases representing unusual features or maneuvers were submitted to

I   and discussed with various members of the panel of consultants prior to the
    final identification.

I         Consistency in the application of the knowledge necessary for making
    identifications was maintained by frequent collaboration among the person­

I   nel involved, and systematic spot checks of the work. In addition to the
    general fund of knowledge required to identify satisfactorily a reported
    unidentified aerial object, an attempt was made to correlate specific data
I   such as flight plans of aircraft, records of balloon releases, weather con­
    ditions, and an astronomical almanac with the reported sighting.

I          The procedure followed in making final identifications deserves ex­
    planation because of the importance assumed by the identification as a basis

I   for statistical treatment. As was mentioned, a conference of four qualified
    persons, two from A TIC and two from the panel of consultants, decided
    upon the final identification for each sighting report. This work was done
I   at A TIC, periodically, as reports became ready.


I         During an identification conference, each sighting report was first
    studied, from the original data, by one person. If that person arrived at a
    decision, it was checked against the preliminary identification; if the two

I   identifications were the same, the report was appropriately marked and
    considered finished. If the two identifications did not agree, the report
    was considered later by everyone participating in the conference until a
I   group decision could be made.


I          If an evaluator was unable to categorize the report as one of the
    common objects or as a natural phenomenon, and his opinion was that the
    sighting should be recorded as UNKNOWN, a group decision was also re­
I   quired on that report before it was considered finished. A group decision
    was necessary on all reports finally recorded as UNKNOWN, regardless of
    what the preliminary identification had been. In cases where a group
I   decision was not made within a reasonable time, the report was put aside
    and later submitted to certain members of the panel of consultants for their

I   op1n1ons. If, after this, disagreement continued to exist, the report of the
    sighting was identified as UNKNOWN.

I                                        13

I

--- PAGE 24 ---
I
     Upon completion of final identifications, all data were transferred to      I
IBM cards, preparatory to analysis.
                                                                                 I
                         ANALYSIS OF THE DA TA                                   I
       Broadly stated, the problem at this point consisted of the judicious
                                                                                I
application of scientific met~ods of categorizing and analyzing the sub­
jective data in reports of sightings of unidentified aerial objects. It was
recognized that an approach to this problem could best be made by a sys­
                                                                                I
tematic sorting and tabulation program to give frequency and percentage
distributions of the important characteristics of sightings. A suggestion       I
that an attempt be made to anticipate all questions that might be asked in
the future about a sighting or a group of sightings, and to provide answers,
was rejected. The systematic approach also made it possible to develop
                                                                                I
a detailed reference manual of the attributes of the sightings included in
this study.                                                                     I
       Thus, at the beginning of the analysis, a detailed plan was developed
for sorting, counting, and tabulating the information from the punched-card
                                                                                I
abstracts of reports of sightings. It was believed at the time, and later
substantiated, that the results of the program for sorting and tabulating
would serve as a, guide for the more sophisticated treatment involving
                                                                                I
statistical methods.

      Also, it was anticipated that any patterns or trends that might be
                                                                                I
found could be subjected to concentrated study in the hope of discovering
significant information relating to the characteristics of "flying saucers".
                                                                                I
Further, it was believed that these trends could serve as certain of the
criteria of validity for any concepts (models) developed in the attempt to
discover a class of "flying saucers".
                                                                                I
       The three parts of this study ( 1) the sorting and tabulation program,   I
(2) the advanced study of the results of that program, and (3) the investiga­
tion of the possibility of conceiving a model of a "flying saucer" from
descriptions reported, are discussed in sections entitled "Frequency and
                                                                                I
Percentage Distributions by Characteristics", "Advanced Study of the Data",
and "The I Flying Saucer' Model".                                               I
       Frequency and Percentage Distributions by Characteristics                I
       The original conception of this study assumed the availability of
                                                                                I
sufficient data to describe adequately the physical appearance, maneuver
characteristics, range, direction, and probable path of the object or
objects observed. However, familiarity with the data, acquired during the
                                                                                I
                                     14                                         I
                                                                                I

--- PAGE 25 ---
I
~      translation and transcription from reports to punched cards, indicated that

I\L,   there would be relatively few specific variables or factors that would yield
       meaningful correlation studies. Either the original data were too subjec­
       tive, or the incompleteness of the original reports-wo1J:_ld seriously reduce

I      the sample of a specific variable.

             Preliminary tabulations of various sortings substantiated the im­
I      possibility of deriving statistical results from certain variables, such as
       movement of the observer during the sighting, sound, shape parameter,

I      size, angular velocity and acceleration, appearance and disappearance
       bearing, initial and final elevation, altitude, and orientation of the object.
       The statistically usable variables presented in this study include the date,
I      time, location, duration, reliability, and method of observation of the
       sighting, and the physical attributes of number, color, speed, shape, light

I      brightness, and identification of the objects sighted.

              The presentation of frequency and percentage distributions of any of

I      the variables must be interpreted in the light of the sample of incidents
       represented. For example, the analysis of the reported colors of the
       objects sighted, based on ALL SIGHTINGS, could lead to misrepresenta­
I      tion of the distribution of the reported color of the objects, because of the
       multiplicity of reports on some of the phenomena. On the other hand, the

I      percentage distribution of the light brightness reported by each observer
       is more likely to be correct than a distribution based on one report for
       each phenomenon. To assure that the most nearly correct presentation

I      was made, and to avoid the possibility· of failure to uncover any pattern or
       trend inherent in the data, the variables were studied on five different
       bases or samples. These samples, and their numerical relation to each
I      other, were as follows:


I                  ALL SIGHTINGS (all reports)
                   UNIT SIGHTINGS, all observers
                                                              3,201 cards
                                                              2, 554 cards
                   UNIT SIGHTINGS, single observer            2, 232 cards
I                  UNIT SIGHTINGS, multiple observers
                   OBJECT SIGHTINGS
                                                                 322 cards
                                                              2, 199 cards

I      The preliminary tabulations indicated that the samples based on UNIT
       SIGHTINGS, single observer, and UNIT SIGHTINGS, multiple observers,

I      would not add materially to this study. Accordingly, although the fre­
       quency distributions were recorded and are available for study, they are
       not presented in this report.
I            The bases of ALL SIGHTINGS, UNIT SIGHTINGS ( referring to all

'I     observers), and OBJECT SIGHTINGS are presented in Appendix A as
       Tables Al through A240. A critical study of these tabulations reveals that
       there is no apparent change in the distribution of any variable from one

I      basis to another, and that no marked patterns or trends exist in any sample.


_I
                                            15

I

--- PAGE 26 ---
I
Graphical Presentation
                                                                                   I
       Graphical representation of the important information contained in
the tables is presented in Figures l through 38. These figures present the
                                                                                   I
distributions of the important variables only by the total nu.mber of cases
in each identification category, since no significant differences were found
                                                                                   I
between the distributions of "Certain'' and "Doubtful" identifications of
objects with respect to the variables. A chronological study of these
figures will afford a broad picture of the tabulated information, without the
                                                                                   I
necessity of a detailed study of the tables.

      A critical examination of the figures will show that no trends, patterns,
                                                                                   I
or correlations are to be found, with the exception of Figures 18 through 30.
The apparent similarity of the distributions shown by these mirror graphs,
                                                                                   I
Figures 18 through 23, was tested by statistical methods which showed that
there was a low probability- that the distributions of the KNOWNS, and
UNKNOWNS by these characteristics were the same. These tests and their
                                                                                  I
interpretation are discussed in the following section. For purposes of this
study, the strategic areas, shown in Figures 32 through 38, and Tables            I
A223 through A240, Appendix A, were designated on the basis of concen­
tration of reports of OBJECT SIGHTINGS in an area. No other interpre­
tation of the tables or remaining charts was deemed necessary.
                                                                                  I
                         Advanced Study of the Data
                                                                                  I
                                                                                  I
       It was recognized that the lack of any patterns or trends, as shown by
the tabulations and graphs, provided an insecure basis for drawing definite
conclusions. Accordingly, shortly before the sorting and tabulation pro­
                                                                                  I
gram was concluded, a program of study of the data was developed to
utilize statistical and other mathematical methods, which could lead to a
more concrete interpretation of the problem.
                                                                                  I
                                                                                  I
Position of the Sun Relative to the Observer

       The first thing that was done was to calculate the angle of elevation of
                                                                                  I
the sun above the horizon and its bearing from true north as seen by the
observer at the time of each sighting. With this information, it could then       I
be determined whether there was a possibility that the reported object
could have been illuminated by light from the sun. In addition, it could be
determined whether an object could be a mock sun ( sun dog) or whether
                                                                                  I
there was a possibility of specular reflection from an aircraft at the posi­
tion of the object, which would give the appearance of a "flying disc".           I
      A program of computation was set up and carried out to obtain the
angle of elevation and the bearing of the sun for each sighting. All informa­     I
tion needed for this calculation was available on the deck of IBM cards.

                                      16
                                                                                  I
                                                                                  I

--- PAGE 27 ---
I
    I
    I
    I
    I
    I
    I
    I
    I
    I                  ,1952,
                        1501=
                           68.3%

    I
    I
    I
    I
    I
    I   Object sightings           All sightings   Unit sightings
         2199 =100%                 3201 = 100%    2554 =100%
    I
        FIGURE I FREQUENCY OF SIGHTINGS BY YEAR FOR OBJECT,
    I            UNIT, AND ALL SIGHTINGS
                                                             A-7479
    I
    I
I                                    17

I
~

--- PAGE 28 ---
I­
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
                                 474 =21.5%
                                                               I
                                                               I
                                                               I
                                                               I
                                                               I
  Object sightings
  2199=100 %
                     All sightings
                     3201=100%
                                              Unit sightings
                                              2554= 100%
                                                               I
                                                               I
FIGURE 2 DISTRIBUTION OF EVALUATIONS OF OBJECT,
         UNIT, AND ALL SIGHTINGS FOR ALL YEARS
                                                      A-7480
                                                               I
                                                               I
                                                               I
                         18
                                                               I
                                                               I

--- PAGE 29 ---
I
I
I
I
I
I
I                      Unknown
                    434=19.7°1.
                                       Astronomical
I                                      479 =21.8 %


I       1952


I                                           Aircraft

I
I
 I
 I
 I
I
 I   FIGURE 3   DISTRIBUTION OF OBJECT SIGHTINGS BY EVALU­
                ATION FOR ALL YEARS WITH COMPARISONS OF
                EACH YEAR FOR EACH EVALUATION GROUP
 I                                                     A•7411



 I
I
I                                 19

11

--- PAGE 30 ---
No. of object sightings
            100           2199                 79                    143                186              169               121         1501
                                                                                                                                                   100

            90                                                                                                                                     90

            80                                                                                                                                     80

            70                                                                                                                                     70

            60                                                                                                                                     60
     +­
     c
     ~      50                                                                                                                                     50
     ~
     Q,J
ro
0    a.     40                                                                                                                                     40

            30                                                                                                                                     30

            20                                                                                                                                     20

            10                                                                                                                                      10

             0I     C\\.\.:::<::<>0)J   L>,,),,),,),,\.'\'\1   l'\;\'\\:\,'\'\'1   I\'\»),),).);!   N>,'\',,'\'\>)j   I\Y\'\\.'\'\"l   RL~        I0
                      - ••                   1947                  1948               1949              1950             1951          1952


           FIGURE 4 DISTRIBUTION OF OBJECT SIGHTINGS BY EVALUATION FOR ALL YEARS AND EACH YEAR

                                                                                                                                              A-7 4 82

--- PAGE 31 ---
----------------------
                   No. of object sightings
                        70          55           83           127         129         183       638        407         166        125       106        105
                   I F+--1 ;..I   11 I I 11   11 I I I 11   11 I I I I I I I I 11   11 I I I I I I I I 11 11 I I 11 I I I I 11 11 I I 11 I I I I II   11 I I 11 1100

              90
       "'Cl
      ·=.c 80
       +-                                                                                                                                                       80
       Cl

      cn 7 0                                                                                                                                                    70
       +­
       u
       cu
      :.0
      0
          60                                                                                                                                                    60
       "'
      .c
      c0 50                                                                                                                                                     50
       ~

      ~ 40                                                                                                                                                      40
"'     0


      -LLJ

       0
       +­
       c
              30                                                                                                                                                30
       cu
       u'­ 20                                                                                                                                                   20
       cu
       a.
              10                                                                                                                                                  10

               0 I l>.':u>l       I\»'\'I     l>,V0J        l\'\:0::1   ~           ~          l'\'001 J:00-:\'I     L),'\).)I   ~ J l'\'\)-'::J l\»>.J        I0
                         Jon        Feb         Mor           Apr         Moy        June       July       Aug        Sept       Oct         Nov       Dec


     FIGURE 5 DISTRIBUTION OF OBJECT SIGHTINGS BY EVALUATION WITHIN MONTHS FOR ALL YEARS
                                                                                                                                                         A-7413

--- PAGE 32 ---
I
    30               20                               10                       0                               10                 20          30

         All years                        I
                                                                      Astronomical
                                                                                                               I
                                                                                                                                                   I
         1947
         1948
         1949
                          I
                              I
                                                      I                                                            I
                                                                                                                       I
                                                                                                                                              I
                                                                                                                                                   I
         1950                     I                                                                        I
         1951
         195 2
                                          I
                                                  I.                                               I
                                                                                                                           I
                                                                                                                                                   I
         All years
         1947
                                              I
                                                                          Aircraft
                                                                          I                I
                                                                                                                   I                               I
         1948
         1949
         1950                             I
                                                  I
                                                      I
                                                                                           I

                                                                                               I
                                                                                                   I                                               I
         195 I                                I                                                I
         195 2                            I                                                                                I
                                                                                                                                                   I
                                                                          Balloons
         All years
         1947
         1948
                                                          I
                                                          I
                                                              I
                                                                                                   I
                                                                                                       I
                                                                                                                                                   I
         1949
         1950
         195 I
                                              I
                                                                  I
                                                                      I            I
                                                                                       I
                                                                                           I
                                                                                                                                                   I
         195 2                                        I                                                    I


                                                                      lnsuf. info.
                                                                                                                                                   I
                                                  I                                                                               All years
                                  I

                                          I
                                              I
                                                                                                                                  1947
                                                                                                                                  1948
                                                                                                                                  1949
                                                                                                                                                   I
                                      I
                                              I
                                                      I
                                                                                                                                  1950
                                                                                                                                  195 I
                                                                                                                                  195 2
                                                                                                                                                   I
                     I
                                                                          Unknown
                                                                                                                                  All years
                                                                                                                                                   I
         I                                                                                                                        1947

                 I
                                              I
                                                  I                                                                               1948
                                                                                                                                  1949
                                                                                                                                  1950
                                                                                                                                                   I
             I
                     I
                                                                                                                                  195 I
                                                                                                                                  1952             I
                                                                           Other
                                                                                                                                  All years
                                                                                                                                  1947
                                                                                                                                                   I
                                                                                                                                  1948
                                                                                                                                  1949
                                                                                                                                  1950
                                                                                                                                  195 I
                                                                                                                                                   I
                                                                                                                                  1952
                                                                                                                                                   I
   30                20
                          Certain
                                                      10                       0
                                                                          Per Cent
                                                                                                               10
                                                                                                                       Doubtful
                                                                                                                                  20          30
                                                                                                                                                   I
FfGURE 6 DISTRIBUTION OF OBJECT SIGHTINGS BY CERTAIN AND
         DOUBTFUL EVALUATIONS FOR ALL YEARS AND EACH YEAR
                                                                                                                                                   I
                                                                              22
                                                                                                                                          A•7414
                                                                                                                                                   I
                                                                                                                                                   I

--- PAGE 33 ---
----------------------
                                                                                                                                                                    5001

                                                                                                                                                                    400




              .,
                       sot                                                                                                                                                 ~              1so
               "'
               C
             :;:
              .t::.

               "'
              ....
              II)

               u
                       50t                                                                                                                                                 r::: X r-MK X\ -ISO

              ~
              0
              0
               .....   40t                    I                                                                                                                            IX XTTIX X      -f40

"'
c,a
              .0


              z
               E
               ::,



                       30t                    VI                                                                                                                           I<. X rTT1 X X-130




                       20                                                                                                                                                                      20




                       10                                                                                                                                                                      10




                        01                         I      JX    X a::,::,,,l::±-¥ tf::::3>H::::t:><I   :-   l'Y:I   Cl      :-1               7 1'¥""-Y£1      l   r I I I I I I I I I 110
                            I   J F M A M J   J    A   s O N 01 J   F M A M J   Js O N O IJ F M A M J J A s O N O IJ
                                                                                    A                                  F M A M J   s O N DI J F M A M J J A s O N DI J F M A M J J A s O N D
                                                                                                                                   J   A
                                         1947                               1948                   1949                       1950                   1951                     1952



      FIGURE 7 FREQUENCY OF OBJECT SIGHTINGS AND UNKNOWN OBJECT EVALUATIONS BY MONTHS,
               1947-1952                                                    C-7485

--- PAGE 34 ---
I
                                                                                                                                                                                                   I
                                                                                                                                                                    Astro-
                         n Astro­
                           nomical                                                                                                          Unknown                                                I
                                                             =22.8

                                                                     \                                                         I
                                                                                                                                   I 71=33.3%
                                                                                                                                   I                                                               I
                                                                     '\
                                                                         \
                                                                          \
                                                                             \                                 I
                                                                                                                   I
                                                                                                                       I
                                                                                                                           I   I
                                                                                                                                                                                                   I
                                                                              \
                                                                                 \\ I/
                                                                                                           I
                                                                                                                                                                                                   I
                                                                                      \ /Excellent
                                                                                                                                                                                 lnsuf. info.
                                                                                                                                                                                  9=4.2 o/o
                                                                                                                                                                                                   I
                                                                                                                                                                                                   I
                                                     I
                                                         I
                                                                          2199=
                                                                                                                                                      \

                                                                                                                                                          ''                                       I
                                                 I
                                                                                                                                                            ''
                                         I
                                             I                               100 o/o
                                                                                                                                                              ''                                   I
                             I
                                 I
                                     I
                                                                                                                                                                '
                                                                                                                                                                ''
                 I
                     I
                         I
                                                                                                                                                                     ''                            I
             I
                                                                                                                                                                       '\
         I
                                                                                                                               /I                                           ''                     I
                                 Doubtful                                                                                  ' I                 Good                              ''
                                                                                                       '
                                                                                                           /
                                                                                                               /
                                                                                                                   /               I
                                                                                                                                   I
                                                                                                                                   I
                                                                                                                                   I
                                                                                                                                                                                      \
                                                                                                                                                                                                   I
                                                                                                                                             Unknown Astr
                                                                                          /
                                                                                              '
                                                                                                  /
                                                                                                      ,'                               I
                                                                                                                                       I
                                                                                                                                       I
                                                                                                                                       I
                                                                                                                                             188 =
                                                                                                                                           24.8 o/o
                                                                                                                                                     nomic
                                                                                                                                                       -2
                                                                                                                                                                                                   I
                                                                                                                                                                                                   I
                                                                                      I                                                '
                                                                                  I
                                                                              I
                                                                          I
                                                                                                                                                                                  croft

                                                                                                                                                                                                   I
                                                                         lnsuf. info.
                                                                          27=3.6%
                                                                                                                                                                                                   I
                                                                                                                                                                                                   I
FIGURE 8 DISTRIBUTION OF OBJECT SIGHTINGS BY SIGHTING
         RELIABILITY GROUPS WITH EVALUATION DISTRIBUTIONS
         FOR EACH GROUP
                                                                                                                                                                                                   I
                                                                                                                                                                                          A-748S
                                                                                                                                                                                                   I
                                                                                                           24
                                                                                                                                                                                                   I
                                                                                                                                                                                                   I

--- PAGE 35 ---
----------------------
                 No. of object sightings
                       2199                   79                     143                                             186                   169                            121                         1501
           100                                                                                                                                    I                                                               100
                     Excellent
           90 t--
                                 ' ' ',                         ,,              -- --                                           ''                            ,,                 ----   ---                      - 90
                                                        ,, ,,                                                                        ',,              ,,,
                                                                                                                                                          ,
                                          '          I'
           80 ,-                                                                                                                                                                                                 - 80
                      Good
           70    -                                                                                          I
                                                                                                                /               ',                                                                               - 10
                                                                                                        I                        ',
      ~    60 ,-                                                                            I
                                                                                                    I
                                                                                                                                      ',              _, ,    ---                  ''                            - 60
                             -                                                      I
                                                                                        I
                                                                                                                                                                                        ',
      C
      cu                          ----               -----                  _v                                                                                                               ',
      u... 50 -                                                                                                                                                                                                  - 50
N)
(JI
      cu
      a. 40 t--
                     Doubtful                                                                                                   ---                   r,                                                         - 40
                                                                                                                I
                                                                                                                 I
                                                                                                                                                           ' ''
           3011-
                                                                                                        I
                                                                                                         I
                                                                                                            I
                                                                                                                                                                  '
                                                                                                                                                                      '                                          - 30
                                                                                                        I
                                                                                                                                                                                   ''
           20It-                 ----- -
                                                                                                I
                                                                                                I
                                                                                                                                                                                        ' ',                     - 20
                                                     ''                                 I
                                                                                            I

            10i""                                         ''                        I
                                                                                                                                                                                                                 - 10
                      Poor                                     ''           -
                                                                                I



             0I                                                                                                             I                                                                     I
                                                                                                                                                                                                             - 0
                     All years                1947                   1948                                            1949                  1950                           1951                        1952


      FIGURE 9 DISTRIBUTION OF OBJECT SIGHTINGS AMONG THE FOUR                                                                                                    SIGHTING          RELIABILITY
               GROUPS FOR ALL YEARS AND EACH YEAR
                                                                                                                                                                                                       A-74 87

--- PAGE 36 ---
(>'
                             •-:-..v
                            0~           ,        ~0·
                           0~          ~     ~ ·,$'     ~(:-
                      ,~          CJ~ ~00~-    t- (:-0
                   t/-"'        .;/' <c~(:-;_o~~~

           ~
                                 ~                                          1 ■111111
                                                                                                                            ~ ~~~
           ~                                                                                 •                              ~ ~
           6 -- 2's- -           so--        1Slbb \o               2s  1
                                                                             s'o    1 s -,ob \b
                                                                                    1
                                                                                                   21s       s'o    T's   ,db\6    21s      s'o       1s    100
     45r-l---Per Cent_ _ / _ \ ~ - - - - - - - - / ~ - - - - - - - - / _ \ _ _ _ _ _ _ _ _/_

     4Qt--1------------J-l-----------/---\---4""'-------..---I-I------------J--


     3 St--1------------,--1-----------,---1--

"'   3 Qt--1-----------'                                       ,   __
 -
~                                                                                    1--,-----1 - -



 uCcu 2 S t - - - 1 - - - - - _ : __ __ 1 - - - 1 - - Civilian                           ------1--       Civilian

 ~
 ~   20t--1-------- 1---1--                                                          1--------- 1--



     I 5t-- \--------I---- I -


                                             e [
                                                                                     1---------1-                   1--------1--                       f--•----



                                                                                     1----------1-                  - - - - - 1--1       Ci villa n    1-----1 - -
     IOI       I
                     I Civilian              t-----                 I Military
                                                                                                  W Military
      51       0 Military                                                            1------                        i--------1


      01       J          I                                         I                I               !              !             ':j Military I
                       Excellent                                             Good                        Doubtful                          Poor

     FIGURE 10 DISTRIBUTION OF ALL SIGHTINGS BY SIGHTING RELIABILITY GROUPS. SEGREGATED BY
               MILITARY AND CIVILIAN OBSERVERS WITH EVALUATION DISTRIBUTION FOR EACH
               SEGREGATtON                                                           A-1411

--- PAGE 37 ---
I
I
I
          IQO,r,:::+=+=11=+:+:::i:+r-r.r-r..r:,-0.;:r+:r+.:r~i-T~_f1_J7...,. 7'_J-rr.._                  +-r+-r                          r...,.r-1-1rr-"'[_"I."I.T..LL~n, IO 0
I
                                                                           7...,.                _,_T_._,-    .._ri.....rrwwT---1-T---1-T
                                                                                                                                        ....




           90                                                                                                                                                           90
I                   Unknown

                                                                                                                                                                        80
I
                                                                                                                                                                        70
I
                                                                                                                                                                        60 +­
I   +­
    c
    cu
    u
                                                                                                                                                                                 c
                                                                                                                                                                                 cu
                                                                                                                                                                                 u
                                                                                                                                                                        50 "­
I   L..
    cu
    a.
                                                                                                                                                                           cu
                                                                                                                                                                                 a.
                                                                                                                                                                        40
I
                                                                                                                                                                        30
I
                                                                                                                                                                        20
I
                                                                                                                                                                         10
I
I                   \
                        \
                            \
                                \
                                    \
                                                                                     I
                                                                                         I
                                                                                         I
                                                                                         I
                                                                                             I
                                                                                                                  i,
                                                                       '
I                                        White        Metallic
                                                                            Not
                                                                           stated OrangE Red                                             Other

I                                       23.5 %          17.7%              12.3% 10.0% 8.1%                                            28.4%


I       FIGURE II DISTRIBUTION OF OBJECT SIGHTINGS BY REPORTED COLORS
                  OF OBJECT(S) WITH EVALUATION DISTRIBUTION FOR EACH
I                 COLOR GROUP
                                                                                                                                                              A•7419
I
I
I                                                                                   27

I

--- PAGE 38 ---
I
         100-                                                                                  ~,....,....,....,....r-T""S....,...,-100         I
         80-                                                                                   >-+-i---+-+.......,._+-+---<__. -   80
                                                                                                                                                I
         60-                                                                   ~~~~~~~~~ - 6 0
                                                            11 or more objects ~~-0~·~~'Y,f
                                                                                                                                                I
                         3-10 objects

 0. 40-
                         255= 11.6 %                               66=3.0%                                                                      I
 ::::,
 0
 ~
(!)
         20-
                                                                              --
                                                                              "C
                                                                              cu
                                                                              0
                                                                                                                               -20 <!>
                                                                                                                                                I
 C


-                                                                              -
                                                                                                                                         C
·-
.t::.
          0-
                                                                              (I)


                                                                              0
                                                                                                                                        .t::.
                                                                                                                                                I
                        ~~

                                                                              -
31';

-                                                                                                                                       -
                                                                              C
                        u 0                                                               ~
 C
 cu 100-
(.)                     0
                         cu O')
                        :0 (X)
                             II
                                                                              (I)

                                                                              u
                                                                              cu
                                                                              °EN
                                                                                 .             ~,...,..T""T""'S,..........~ -      IO O cu
                                                                                                                                          C

                                                                                                                                        (.)
                                                                                                                                                I
 ~
 cu
a.. 80-
                        (\J (0
                            O')
                                             I object                         -
                                                                              o
                                                                                  0       II

                                                                                          v
                                                                                          (0   ;c:...~-<":-<":v:vvccc;
                                                                                                    ,,....,,...."",,v'X,Y~'C◊O: - 8 0 Q..
                                                                                                                                          ~

                                                                                                                                          cu    I
                                          1636= 74.4%                          cu
                                                                                  ~




         60-
                                                                              .0

                                                                              z
                                                                                  E
                                                                                  ::::,        1----------i-                       60
                                                                                                                                                I
         40-
                                                                                                                                                I
         20-
                                   100- .................- ........-
                                                                                                                               -20
                                                                                                                                                I
                                  o.    t-+-+-+-+-+-+-,r-+-t-+t Unknown



          o_
                                  ::::,
                                  e 80-~~V~v"~V'~-~.,.._.,..ic:J',.~ Others
                                  (!)
                                                                                                                                                I
                                                                lnsuf. info.
                                  c
                                                                                                                                                I
                                  -
                                  :C 60-
                                  31';
                                  -c 40-
                                                                Balloon

                                                                                                                                                I
                                   cu                           Aircraft
                                  (.)
                                  ~
                                  cu 20-
                                  a..
                                                                                                                                                I
                                                                Astronomical
                                                                                                                                                I
         FIGURE 12 DISTRIBUTION OF OBJECT SIGHTINGS BY NUMBER OF                                                                                I
                   OBJECTS SEEN PER SIGHTING WITH EVALUATION DISTRI­
                   BUTION FOR EACH GROUP
                                                                                                           A-74 90
                                                                                                                                                I
                                                                                                                                                I
                                                   28                                                                                           I
                                                                                                                                                I

--- PAGE 39 ---
----------------------
-   -   --~---------------------------------------------




                100---~-----~~~~~

                9 0-1    No t
                                       1J ! J..111~~1   1
                                                         mm !!!!!!m
                                                            1   1




                                    /~~"'TTT"l7"7"''7"7"'7"?'"7~~~
                                                                                   lnsuf. info.



                eo-1 ~':.~.~. / / ' ~111111-1-----------,1111 1111111
        .
                70
                                    1111111111111~_~1---------,-11111 I111111
                     ~ov;ra~.mi ~ ~ / ; , •



            ~      61
                ::~ ;~;.in        ~r::i IIIIIIIIIIIIIIIIIl~_~~mffll 11111111111111
    = ~         40
                     -   ~~~:.-   /~~-IIIIIIIIIIIIIIIIIIIIIR===:=filllllllllllll lllll
                30

                          5 ✓~:::~I
                     -~:~30·:::     11111111111111111111111~-====:~BI 1111111111
                : ~: :~e?:: :::::-111111111111111 ~;:==;=91111111111111
                            -,,~-1,1111111,11m1111111
                  O-D~;~t!;:n
                                     0    IO   20           30        40      50        60        70   80   90         100
                                                                    Evaluations in Per Cent


                FIGURE 13 DISTRIBUTION OF OBJECT SIGHTINGS BY DURATION OF SIGHTING WITH EVALUATION
                          DISTRIBUTION FOR EACH DURATION GROUP
                                                                                                             A- 7491

--- PAGE 40 ---
No. of object sightings
                                  70              55                   83                127                12.9
                                                                                                               -              183                 63_8                   407             - -
                                                                                                                                                                                         1.66                 L25                    106                     LOS
            100                                                                                                                                                      I
                                                                                                                                                                                                                                                                    100


            90I·                                                                                                                                                                                                                                                    90
     en                          Not
     Cl                         statec
     C
     :;: 80 -
                                                                                                                                                                     .         ,-,                                                                                 . 80
     .c.                                                                                                              /
                                                                                                                                     ''                      I
                                                                                                                                                                 I                   -      -                                                            I
     Cl
     ·-
     (/)
                                                                                                ,,
                                                                                                                    /
                                                                                                               -"' ....
                                                                                                                                                         r
                                                                                                                                                                                                 ''                                                  I
                                                                                                                                                                                                                                                    II
                                                                                                                                                                                                          '                                  II
                                                                                                        I                                                        I             '\                                   '\\                                             70
                                fn;;in -
                     ~
     -      70                                                                                    I                                                          I                                                                               II
     u                                                                            I                                                   ''                                            ''                                                              I
     Cl)

     'B
                                              -          I\                  I
                                                                             I
                                                                                               ,I                                                                                                    '                           '               I
                                                                                                                                                                                                                                                    I




                                                                                                                                                                                                                                                                          -
                                                          \'
     0 60                                                     '\ '                i                                                                                                                                  \                           I
                                                                                                                                                                                                                                                                    60
                                                                             I                                                                                                                                           \                      I
     en
                                6-30                               '                                                                                                                                                         \              I
                                                                                                                                                                                                                                             I
                                                                                                                                                                                                                                                                          C
     .c.
     1:0 50I u
                                min
                                                                                     I              -                   -             ..                      ;'               --                \
                                                                                                                                                                                                                                 \
                                                                                                                                                                                                                                                         I
                                                                                                                                                                                                                                                                          Cl)
                                                                                                                                                                                                                                                                          (.)

                         •               ,;
                                              /          ,.,                 I
                                                                                 I                                                                       I"
                                                                                                                                                                                                     \
                                                                                                                                                                                                                                                     I
                                                                                                                                                                                                                                                      I
                                                                                                                                                                                                                                                         I
                                                                                                                                                                                                                                                                    5 0 '­
                                                                                                                                                                                                                                                                        Cl)
                         I I)
     ~                                                          '                                                                                                                                                   \                                I                  a.
                         o 61sec                                                                                                                                                                                     \
"'
0    ~ 40I U)I
      0
                              to                                                                                                                                                                                         \
                                                                                                                                                                                                                             \
                                                                                                                                                                                                                                             I I
                                                                                                                                                                                                                                                I
                                                                                                                                                                                                                                                 I
                                                                                                                                                                                                                                                                   . 40


     --
     w                   ;;; 5min                                                                                                                                              1·,                                           \
                          \
                                       -                  ;
                                                              ,;                 -                  -
                                                                                                                    ,;'
                                                                                                                   ~·


                                                                                                                                      '       ~
                                                                                                                                                         I'
                                                                                                                                                              I                      -          '\
                                                                                                                                                                                                                                 I          ' I
                                                                                                                                                                                                                                           - II
      0     30I                 I1_-~y
                                 se_e     \                                                         I
                                                                                                                   V
                                                                                                                        ,;'          I\
                                                                                                                                          \
                                                                                                                                                         /
                                                                                                                                                                                ..                   ''                  ..                  f I
                                                                                                                                                                                                                                                                    30
      C                                       \
                                                         .,. ,,·
                                                                                                /                                             '                                                 ,-,
      CV
     U 20 r
                                10-1v
                                 sec     '\'\•
                                                                             '                 I'

                                                                                                                   I'
                                                                                                                        ,,,          r,
                                                                                                                                                                                                   '                     ..                  I
                                                                                                                                                                                                                                               I

                                                                                                                                                                                                                                                                   . 20
      '­                                  '             - ·,                                        /
                                                                                                                                          \
                                                                                                                                                             /
                                                                                                                                                                 /              '                -,                 .......                 -,,,·.,,.

                                                                                                                                      ..'                     ,,.               ...
                                                                                                                                                         ~
      Cl)
                                                                                 -             V
     a.                         5 sec
                                 ond
                                                         I' '
                                                          \
                                                            '                    ...              ,,·                    -                               I'
                                                                                                                                                                                                ,-,      .            ,,,,
            10   I
                                                                                               I"                                                                                                                                                                   10
                                less

             0                                                                                                                                                                                                                                                      0
                                Jon               Feb                  Mor               Apr                May               June                July                   Aug             Sept                 Oct                    Nov                     Dec


     FIGURE 14 DISTRIBUTION OF OBJECT SIGHTINGS BY MONTHS AMONG THE EIGHT DURATION
               GROUPS FOR ALL YEARS                                         A-7492

--- PAGE 41 ---
----------------------
           100-
                  ___              ......,..,,,,,,,,,, .......-K\'.\,\.\.\.\.\.\.\l 11 11 I 1111 I P/7?777J1f------txx5o&'x54 I I I I I I 111111 I 11
                                            23.5%                                                          lnsuf. info

            90-         Not
                       stated


           ---i'·"~::-.1III IIII III I 1•::====~111II IIIIII I IIII
            80-

            70-         Other




      -
      C:
          --------r-f;'~ilIIII
            60- enticular
                         Flam
                                             I IIIII~
                                                I I    I     IIIII
                  \~~:~11111111111111~:====;::====::-[ 111111
      QJ
      0     50-
      ~
      QJ
      Q.
(II
            40-

            30-
                  I
                      Elliptical
                                          \\   ~
                                                     1111•
                  4\~11111111111111111111111~~::==:=-.IIIIIIIIIII
            20-

            10-


        i. .--.J, .:~: _ _ 111111.1111111.I ~ .11111111 I.I 111111
             o_
                        Shape
                                               0        10        20        30        40        50
                                                                                 Evaluation in Per Cent
                                                                                                          60         70        80        90        100


           FIGURE 15 DISTRIBUTION OF OBJECT SIGHTINGS BY SHAPE OF OBJECT(S) REPORTED WITH
                     EVALUATION DISTRIBUTION FOR EACH SHAPE GROUP
                                                                                                                                      A-7493

--- PAGE 42 ---
ioo-r-----------K'Z\:\.~\:i 11111111111 IV/T///1                              .KXXXX?t 111 I I 1111111

     90-



     eO-ln;~::~ed' ,/~~                                                    11111~~~::::::=::::~111111111111

   ~ : ~I   ffl • ~-u   ;:::~:~II I111111111111111 ~t:==:=:;: : : : : ==~t: :=: : =jgm I1111111111111111

~ i ::~ :~i~t / i B II II IIII IIII IIIl~t=:::=:::=t:=:::::::=:::=::::::::~91111111111111111
    : ~:~;~~~o :~::;~]! 1111111111~~11111111111
      1    15t


      :~       ~~~~:-1,111111.-t:::==c::::==:t:::==,_____ffl 1111 l1111111
              :~::Y
                              0 ·    10  30 20  40       50      60 70  80     90                        100
                                          Evaluation in Per Cent
     FIGURE 16 DISTRIBUTION OF OBJECT SIGHTINGS BY REPORTED SPEED OF OBJECT(S) WITH
               EVALUATION DISTRIBUTION FOR EACH SPEED GROUP
                                                                                                A-7494

--- PAGE 43 ---
----------------------
                 No. of all sighting
                          3201                          117                      205                     164                                 306                                    160                                    2018
          100-                                                                                                                                                                                                                         -100
                        Location
   ~ 90-                  not                                              ,,,                                                                                                             ~
                                                                                                                                                                                                                                       -90
    ...
   +­                                                             ., ,/'                ''                                                                                      I
                                                                                                                                                                                            '
                         stated , ... ...         -                                          ' ' ',                                                                         I                    ''
    &,  80-                                                                                                                                                             I
                                                                                                                                                                            I
                                                                                                                                                                                                           ''                          -so
    <11                                                                                                                                                             I
   0::                                                                                                          \                                               I
                                                                                                                    \
                                                                                                                         \                                  I
    u,    70-                                                                                                                                           I                                                                              -70
   ·-"' 60-
                                                                                                                             \
                                                                                                                                 \                  I
    C                                                                                                                                \              I
                        Outdoors                                                                                                         \

   .c
   +-                                                                                                                                                                                                                                  -60
   ·-"'
   f/)  50-                                                                                                                                                                 ,,                                                         -50
                    ~
                                                                                                                                                                                           '
                                                                                                                                                                                           ,,
                                                                                                                                                                                           ~ \


                                                                                                                                                    , ,, ,
   ~
                                                                                                                                                       //
c,,.._              "
                   .c                                                  ,,--                                                                          ,                                         '\
                                                                                                                                                                                                   \,,,
                                                                                                                                                    , I,
          40-      +-                                         1_-:;.,'                  ~
(1,1 0
                   0                    .--:-
                                    ._,,,,,,                                             ~                                       ,,,                                                       \
                                                                                                                                                                                               \               ,,                      -40
                                                                                          ~                              ,,,, ,,,
   +­               '
                                         ',/                                               ~                                                            ,                                          \               ~
    c
    <11   30-           In bldg.
                                                                  ''                                ~~              .,
                                                                                                                11~,"                               /                                                  \
                                                                                                                                                                                                                                       -30
   u                                 /
                                          /                            ''                    ...... _            ,.,,.,
                                                                                                                                 ,.,,                                                                      \
                                                                                                                                                                                                               \
                                                                                                                                                                                                                   \
    I,.                                                                                                                                                                                                                \
   "20-                                                                                                                                                                                                                                -20
                        In plane
                                         ,.,,,, ,,,-
   o.                                                         '
          10-
                                    II
                                                                  ' ' , ...             _, ,   --               ---                                 ----                                       ........                                -10
                        In car
           0                                                                                                                                                                                                                           _Q
                        All years                      1947                      1948                    1949                                1950                                   1951                                   1952

          FIGURE 17 DISTRIBUTION OF ALL SIGHTINGS BY OBSERVER LOCATION FOR ALL YEARS AND
                    EACH YEAR
                                                                                                                                                                                                                             A-74 95

--- PAGE 44 ---
Total Less Unknown                                     Unknown
                         Pe-r Cent                                          Per Cent
            30   25      20    15   10    5   0                0   5   10    15   20   25   30
        I   I    I        I    I     I    I                        I   I     I    I    I    _1       _j




                                                    White


                                                  Meta II ic


                                                  Not stated
Of
~

                                                   Orange


                                                     Red


                                                    Other



     FIGURE 18 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY COLOR,1947-1952
                                                                                                 A-7496

--- PAGE 45 ---
-~--------------------
                         Total Less Unknown                                              Unknown
                              Per Cent                                                    Per Cent
           80   70   60    50   40   30   20   10       0                0   IO   20   30 40 50 60   70   80
       I   I    I    I      I   I    I    I    I




                                                               One


                                                   -
                                                               Two


c,,
(JI                                                           Three
                                                                to
                                                               ten
                                                       ..     Eleven
                                                                 or
                                                       ■
                                                               more
                                                       ■




                                                            Not stated
                                                       ■




      FIGURE 19 COMPARISON OF KNOWN ANO UNKNOWN OBJECT SIGHTINGS BY NUMBER OF
                OBJECTS PER SIGHTING, 1947-1952
                                                                                                     A- 7497

--- PAGE 46 ---
Total Less Unknown                                                    Unknown
                           Per Cent                                                          Per Cent

             40   35   30   25   20   15   IO   5       0                  0   5   IO   15   20   25    30   35   40
         I   I    I    I    I    I    I     I   I                              I   I    I     I   I     I    I    I    I




                                                            Stationary


                                                             Less than
                                                             100 mph

                                                            100 to400
(1,1                                                          mph
0)


                                                            More than
                                                            400mph

                                                -           Meteor-Ii ke
                                                                           -
                                                    -
                                                        Not stated
                                                                           -

       FIGURE 20 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY SPEED, 1947-1952
                                                                                                                  A-7491

--- PAGE 47 ---
----------------------
                       Total Less Unknown                                      Unknown
                            Per Cent                                           Per Cent
                  30   25    20   15    10   5   0                0   5   10   15   20    25   30


                                                     5 seconds
                                                                  t
                                                      or less
                                                       6-10
                                                      seconds
                                                       11-30
                                                      seconds
                                                       31-60
"'...a                                                seconds
                                                     61 seconds
                                                     5 minutes
                                                       6-30
                                                      minutes

                                                 More than
                                                 30 minutes

                                                 Not stated



         FIGURE 21 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY DURATION, 1947-1952
                                                                                                A-7499

--- PAGE 48 ---
Total Less Unknown                                                Unknown
                    Per Cent                                                       Per Cent
          50 45 40 35 30 25 20 15     10   5   0                 0   5   10   15 20 25 30 35 40 45 50


                                                   Elliptical

                                                    Rocket
                                                      and
                                                    aircraft
                                                   Meteor or
                                                     comet
                                                   Lenticular,
c,,                                                conicol or
a,                                         U        teardrop

                                                     Flame


                                               Other shop,

                                               Not stated



      FIGURE 22 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY SHAPE, 1947-1952
                                                                                                   A•7500

--- PAGE 49 ---
----------------------
                    Total Less Unknown                                                    Unknown
                        Per Cent                                                          Per Cent
               60   50   40      30   20   10       0                 0         IO   20   30   40       50   60
           I   I    I        I   I    I    I                                    I    I    I     I       I    I        I



                                                         Sunlight on
                                                         mirror or
                                                         aluminum
                                                -        Sunlight on     -
                                                         plaster,
                                                --       stone or soil

                                                          Brighter
                                                                         -
                         /



(1,1                                                     than moon
                                                                         -
U)
                                                    ~




                                                         Like moon
                                                    ..                   ,...
                                                 -                       ...
                                                          Duller
                                                                                                    '
                                                         than moon ...
                                                 -
                                                         Not stated




       Fl GURE 23 COMPARISON OF KNOWN AND UNKNOWN OBJECT SIGHTINGS BY LIGHT BRIGHTNESS,
                  1947-1952
                                                                                                                 A•7501

--- PAGE 50 ---
Total Less Astronomical                            Astronomical
                    Per Cent                                      Per Cent
        40     30      20       10     0               0   10       20         30   40

                                       j               t
                                            January
                                            February
                                             March
                                             April
                                             May
..
0
                                             June
                                             July
                                           August
                                           September
                                            October
                                           November
                                           December


     FIGURE 24 COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED AS
               ASTRONOMICAL VERSUS TOTAL OBJECT SIGHTINGS LESS ASTRONOMICAL

                                                                                     A-7502

--- PAGE 51 ---
----------------------
                 Total Less Aircraft                            Aircraft
                       Per Cent                                 Per Cent
         40      30      20       10   0               0   10     20       30     40


                                            January
                                                       t
                                           February
                                            March
                                             April
                                             May
                                             June
~

                                             July
                                            August
                                           September
                                            October
                                           November
                                           December


    FIGURE 25   COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED AS
                AIRCRAFT VERSUS TOTAL OBJECT SIGHTINGS LESS AIRCRAFT
                                                                                A-7503

--- PAGE 52 ---
Total Less Balloon                              Balloon
                         Per Cent                                  Per Cent
            40      30     20        10   0               0   10     20       30       40

                                          l   January
                                                          t
                                              February
                                               Morch
                                               April
                                                Moy

~                                               June
I\)

                                               July
                                              August
                                              September
                                               October
                                              November
                                              December


      FIGURE 26   COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED
                  AS BALLOON VERSUS TOTAL OBJECT SIGHTINGS LESS BALLOON
                                                                                   A-7 504

--- PAGE 53 ---
----------------------
                 Total Less lnsuff icient Information                     lnsuff icient    Information
                             Per Cent                                               Per Cent
            40          30       20        10         0               0       10          20     30       40
                         I        I        I
             \


                                                  j
                                                           January

                                                          February
                                                           March
                                                           April
                                                            May
                                                            June
  •
  c,,
                                                            July
                                                           August
                                                          September
                                                          _ October
                                                          November
                                                          December


        FIGURE 27 COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED AS
                  INSUFFICIENT INFORMATION VERSUS TOTAL OBJECT SIGHTINGS LESS INSUFFI­
                  CIENT INFORMATION
                                                                                                         A-7505




--/

--- PAGE 54 ---
Total Less Other                              Other
                       Per Cent                                  Per Cent
          40       30     20       10   0               0   10     20       30   40


                                             January
                                                        t
                                            February
                                             March
                                              April
                                              May

..                                            June
                                              July
                                             August

                                            September
                                             October
                                            November
                                            December


     FIGURE 28   COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED AS
                 OTHER VERSUS TOTAL OBJECT SIGHTINGS LESS OTHER
                                                                                 A-7506

--- PAGE 55 ---
----------------------
                 Total Less Unknown                            Unknown
                       Per Cent                                Per Cent
          40    30      20       10   0               0   10     20       30   40

                                      j
                                           January
                                                      t
                                          February
                                           March
                                           April
                                            May
                                            June
~
u,
                                            July
                                           August
                                          September
                                           October
                                          November
                                          December


     FIGURE 29 COMPARISON OF MONTHLY DISTRIBUTION OF OBJECT SIGHTINGS EVALUATED AS
               UNKNOWN VERSUS TOTAL OBJECT SIGHTINGS LESS UNKNOWN

                                                                               A•7507

--- PAGE 56 ---
I
                   90
                                                                                                                                                                                                                            I
                   80

            -                                                                                                                                                                                                               I
    -                   \
            C
    -co 60  Cl>

      ...
    ~ cu 40 a.
                                                                                        Unknown
                                                                                                                               V\                                                                                           I
                                                                                    I ~ "~~ \ I
                                                                                                           \

                                                ~                                                                                                           \_        ,                                    '-
                   20
                    r
                             i..:::: ~
                                         -- I            ....... "'-::
                                                                         ::....                                                           ~-           -,
                                                                                                                                                          I~
                                                                                                                                                               ~- - ,1/ I'- I       \
                                                                                                                                                                                                           ~




            -
                   3~                                                                                                                                                                                                       I
                        \
    1/)
            C      60
    C
            (.)
            Cl>
    ~
    0        ... 40                                                                                                            ('                                                                                           I
                                                                                                          \ I \\._
    C       Cl>                                                                         Unknown
    ~       a.
                                                ,a:.._                    ~-~~,
                                                                             "hf/,'                                                                                ;, -~                               ,..:::..
                                                                                    I
                                                                                                                                                                            \
                   20
                             IL ~ -- I "'                      .:.;:; ,._                                                                                                                        - ,:,,,               I
                   3§                                                                                                                                  ~----
                                                                                                                                                                                        '                         '         I
            -
    -
    ...0 (.) 60
    1/)
            C
            Cl>


    <t a.... 40
                        I
                         I
                         I
                                                                                                                               v                                                                                            I
                                                                                    / , Vr\ ,/ \b< ~, ✓- ~ r:..:: ,, h.,v y
            Cl>
                                                                                        \Unkn~~ h
                                                                                                                           J,,
                   20

                   3§
                               ,
                              , ''
                                         -   ) ~ -- V-- ~ ,                               ~L
                                                                                                  ----    ~                                       ~       _,_:,,
                                                                                                                                                                                \
                                                                   

This text is truncated. The complete file is available at the official source.

View the official file

Congressional Context

Where this record connects to the congressional record and the people in it.

Related Intelligence