USAF Historical Archives ASI(ASHAF-A) Maxwell AFB, Ala 36112 I BRIEF HISTORY OF PRQJgCT BLUEBOO A. GEhERAL 1. In the fall of 1 947 the Force took official notice of reports "flying saucers" because t h e reiJorts f indicated that the problem might be r e orce responsibility for the air defen 1i&tl;t;tate s <A~r ated to the Ai e of the United 2. On December 30, 1947 the Air Force directed its Air Materiel Command at Wright-Patterson Air Force Base, Ohio, to establish a project to collect and evalu- ate all availab~ facts concerning ''flying saucer" sightings. 3. On December 27, 1949, after 37 5 reported s1ght1ngs had been investigated, the Air Force, with the concurrence of the Army and the Navy, a nnounced the find- of the " f l ying saucer" project. 4. The evidence at t hat time indicated that the majority of the reports of unidentified flying objects could be accounted for a s misinterpretations o f various c onventiona l objects, a mild form of hysteria, meteoro- logical phenomena, light aberrations, or hoaxes. 5. There r emained, however, a number of un- explained sighting s , and the Air Forc e has c ontinued its investigations inasmuch a s it i s an Air Force re- s ponsibility t o identify and a nalyze aerial phenomen a that c ould possibly be a menace to the Unit e d States. 6 . To date, the Air Forc e has undertaken to investigate and analyze about 5,00 0 reports dealing with these phenomena. As before, most of the reports were identified and disposed of as friendly aircraft erroneously reported , known electroni c and meteorological phenomena, light aberrations, hoaxes, and other known natural oc- curences or man - made objects. 7. The unexplain e d reports, however, which are in the order of approxi,1.ately 10 percent of the total, cannot be definitely associated with these familiar things. Diffi~ultz in Eval~ating Repor 8. The d iffi culty in disposing of these u n - explained reports i s based largely upon the lack of a ccurate basic data such a s size, shape, compo sition and flight characteristics (speed, acceleration , altitude, exac t maneuver pattern , etc.) of the ob j e cts. 9 . Althou gh some instruments which are usef u l in obtai ning more accurate data of this type have been avail- a ble, the reports based on sightings with these instruments have been very i nfrequent a n d co.aprise a n extr emely small percentag e o f the total. Moreover, even these reports have not i ncluded much of the informat1on required. 10. Because of the i nadequacy of this ba sic data, the Air Fruce has i n the past d e voted its e f f orts primarily to detern.i ning whether t hese unexplain e d sighting s 1.ndicated the existence of a menace t o the United btates. Initially it was believed that some pattern might evolve from the study of a large vol~e of report s . To date, no p attern has materialize d to reveal anything whatsoever which can be interpreted as indicative of purpose or consiste ncy or which c a n be c onstrued a s a menace t o the United States. Nonetheleas, sin c e these unexplain e d si ghtin g s per s i st, the Air Force will continue its i n vestig ations, givin g the problem adequate but n ot frantic att ention. 11. Re ports of similar phenomen a g o back to Biblica l time s . There have been flurrie s of t hem in various c enturies. The current series of s ighti n g s bega n erally in 194 6 . 1 2 . There are ma r y reasons why the volume of t hese reports has increased materially during the pa s t few years. Aerial activity originated by man h a s i n - creased, and peop l e today have a gr eate r curiosity ab ou t the activity t hen before. Also, our p resent e fficient COilltlunication facilities and 11ews media provide an i n - centive for reporting Llnusual observations, for publicis- ng t hem a n d for recor d ing them. However, the a bility to measure these phenomena doe s not seem t o have advanced in step with opportun i ties for obser ving them. The Air Fa."' ce believes that most of these phenome11a will gradually b e understood as more is known aoout o ccurrences i n the u pper atmosphere. B. RADAR SIGHTINGS 1. The Ai r Force has received many reports of unusua l imag e s on radar scopes. I t is fairly well establishe d at some of these images are g r ound object s reflected f r om a layer of warm air above the earth (a ternpe ratur e inversi~n). 2. Temperature inversion relfections can give a return on a radar scope that is a s sharp as that received f rom a n aircraft. Speed rangen of' these returns are re- rtedly from zero to fantastic speeds. The "objects" also a ppear to move in all directlons. 3. Suc1 radar s i ehting s have resul t ed in hun- reds of fruitless intercept eff orts. 4. One scientific theory holds that l ight can be similarly reflected f rorn a layer of warm air above bhe earth and, if proved to be correct, this could account for some visual sightlngs. 5 . Bearing out thetheory of temperature i n - version reflection is an i ncident which occurred i n January 1951 near Oakridge, Tennessee. Two Air Force air- craft attempted to intercept an unidentified "object" and actually established a radar ''lock'' on the object. Their altitude at the time was 7,000 feet. The u n identi- fied object, according to their radar, a ppeared to be at an e~vation of ten to twenty-five degrees. Three passes were made in an a ttewpt to close on the object. In each instance the pilots reported that their radar led them firs t upward and then down toward a specific point on the ground. 6. Ionized clouds are believed to be the cause of some unidntified radar returns. Thunderstorm activit y is i d Gntifiable by radar, and radar i s used for the pur- pose of avolding thunderstorms. I n addition, radar has picked up many objects first reported as "Unidentified Phenomena" which were late r identified as aircraft, birds, balloons, ice f or mation s in the air, or other kn o\vn aerial objects or manifestations. C. COL'JCLUSIO '; S 1. The Air Force has stated in the past, and re- affirms at the present time, that the s e unider.tified aerial phen omena are not a secret weapon, missile or aircraft, develped by the Unite d States. None of the three military d e partmen t s nor any other a g e ncy in the g overnment is c on aucting experiment s , classified or otherwise, with flying objects which could be a basis for the reported phenomena. As far a s is known there is nothing in them that is associated with material or vehiclestt~t are ~irected a gainst the United States , from/~BBn~y or from other planets.