Project Blue Book

From Academic Kids

Project Blue Book was one of a series of systematic studies of Unidentified flying objects (UFOs) conducted by the United States Air Force. It was the second revival of such study, started in 1952, and was active up to January 1970, as it had been ordered for termination in December 1969.

The goal of the project BLUE BOOK was to determine if UFOs were a potential threat to national security. Thousands of UFO reports were collected, analysed and filed. As the result of the Condon Report, Project Blue Book was shut down in 1969. This project was the last publicly known UFO research project lead by the USAF. [1] (


Previous Projects

Public USAF UFO studies were first initiated under Project Sign at the end of 1947, following many widely-publicised UFO reports (see Kenneth Arnold). Project Sign was initiated specifically at the request of General Nathan Twining, chief of the Air Force Materiel Command at Wright-Patterson Air Force Base. Wright-Patterson was also to be the home of Project Sign and all subsequent official USAF public investigations.

Sign was officially inconclusive regarding the cause of the sightings. However, according to Captain Edward J. Ruppelt, the first director of Project Blue Book, Sign's initial intelligence estimate, written at the end of the summer of 1948, concluded that the flying saucers were real craft, were not made by either the Russians or U.S., and were likely extraterrestrial in origin. This estimate was forwarded to the Pentagon, but subsequently ordered destroyed by Gen. Hoyt Vandenberg, USAF Chief of Staff, citing a lack of physical proof. Vandenberg subsequently dismantled Project Sign.

Project Sign was succeeded at the end of 1948 by Project Grudge, which had a debunking mandate. Ruppelt referred to the era of Project Grudge as the "dark ages" of early USAF UFO investigation. As might be expected, Grudge concluded that all UFOs were natural phenomena or other misinterpretations, although it also stated that 23 percent of the reports were inexplicable.

Project Blue Book

According to Ruppelt, by the end of 1951, several high-ranking, very influential USAF generals were so dissatisfied with the state of Air Force UFO investigations that they dismantled Project Grudge and replaced it with Project Blue Book in early 1952. By the time Project Blue Book ended in 1969, it had collected 12,618 UFO reports, and concluded that most them were misidentifications of natural phenomena (clouds, stars, et cetera) or conventional aircraft. A few were considered hoaxes. 701 of the reports—about six percent—were classified as unknown. The reports were archived and are available under the Freedom of Information Act, but names and other personal information of all witnesses have been blacked out.

The first head of the project was captain Edward J. Ruppelt. By his order, a standard reporting form for UFOs was developed. He was also the one who officially coined the term UFO, to replace the inaccurate and suggestive flying saucer, which had been used to that point. He resigned from the air force some years later, and wrote the book The Report on Unidentified Flying Objects, which described the study of UFOs by United States Air Force from 1947 to 1955.

Astronomer Dr. J. Allen Hynek was the scientific consultant of the project. He worked for the project up to its termination and initially created the categorization which has been extended and is known today as Close encounters. He was a pronounced skeptic when he started, but said that his feelings changed to a more wavering skeptism during the research, after encountering a few UFO reports he thought were inexplicable.

Robertson Panel

In July 1952, after a build-up of hundreds of sightings over the previous few months, a series of radar detections coincident with visual sightings were observed near the National Airport in Washington, D.C. These sightings led the Central Intelligence Agency to establish a panel of scientists headed by Dr. H. P. Robertson, a physicist of the California Institute of Technology, which including various physicists, meteorologists, engineers, and one astronomer (Hynek). The Robertson Panel first met on January 14, 1953.

Ruppelt, Hynek, and others presented the best evidence, including movie footage, that had been collected by Blue Book. After spending only 12 hours reviewing 6 years of data, the Robertson Panel concluded that most UFO reports had prosaic explanations, and that all could be explained with further investigation, which they deemed not worth the effort.

In their final report, they stressed that low-grade reports were overloading intelligence channels, with the risk of missing a genuine conventional threat to the U.S. Therefore, they recommended the Air Force deemphasize the subject of UFOs and embark on a debunking campaign to lessen public interest. They suggested debunkery through the mass media, including The Walt Disney Company, and using psychologists, astronomers, and celebrities to ridicule the phenomenon and put forward prosaic explanations. Furthermore, civilian UFO groups "should be watched because of their potentially great influence on mass thinking. . . The apparent irresponsibility and the possible use of such groups for subversive purposes should be kept in mind."

In brief, the Robertson Panel was recommending controlling public opinion through a program of official propaganda and spying. It is the belief of many ufologists that these recommendations helped shape Air Force policy regarding UFO study not only immediately afterwards, but also into the present day.

Aftermath of Robertson Panel

In his book (see external links) Ruppelt described the demoralization of the Blue Book staff and the stripping of their investigative duties following the Robertson Panel. As an immediate consequence of the Robertson Panel recommendations, in February 1953, the Air Force issued Regulation 200-2, ordering air base officers to publicly discuss UFO incidents only if they were judged to have been solved, and to classify all the unsolved cases to keep them out of the public eye.

The same month, investigative duties started to be taken on by the newly formed 4602nd Air Intelligence Squadron (AISS) of the Air Defence Command. The 4602nd AISS was tasked with investigating only the most important UFO cases with intelligence or national security implications. These were deliberately siphoned away from Blue Book, leaving Blue Book to deal with the more trivial reports.

General Nathan Twining, who got Project Sign started back in 1947, was now Air Force Chief of Staff. In August 1954, he was to further codify the responsibilities of the 4602nd AISS by issuing an updated Air Force Regulation 200-2. In addition, UFOs (called "UFOBs") were defined as "any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object." Investigation of UFOs was stated to be for the purposes of national security and to ascertain "technical aspects." AFR 200-2 again stated that Blue Book could discuss UFO cases with the media only if they were identifiable. If they were unidentified, the media was to be told only that the situation was being analyzed. Blue Book was also ordered to reduce the number of unidentifieds to a minimum.

All this was done secretly. The public face of Blue Book continued to be the official Air Force investigation of UFOs, but the reality was it had been reduced to a sham organization doing very little serious investigation, and had become almost solely a public relations outfit with a debunking mandate. To cite one example, by the end of 1956, the number of cases listed as unsolved had dipped to barely 0.4 percent, from the 20 to 30% it had been only a few years earlier.

By the time the frustrated Ruppelt left in August 1953, his staff had been reduced to just two subordinates and himself. His replacement was a noncommissioned officer. All who succeeded him as Blue Book director exhibited either apathy or outright hostility to the subject of UFOs, or were hampered by a lack of funding and official support.

Ruppelt's brief tenure at Blue Book is considered the high-water mark of public Air Force investigations of UFOs, when UFO investigations were treated seriously and had support at high levels. Thereafter, Project Blue Book descended into a new "Dark Ages" from which it never emerged.

Project Blue Book Special Report No. 14

In late December 1951, Ruppelt met with members of the Battelle Memorial Institute, a think tank based in Columbus, Ohio, near Wright-Patterson Air Force Base. Ruppelt wanted their experts to assist them in making the Air Force UFO study more scientific. It was the Battelle Institute that devised the standardized reporting form. Starting in late March 1952, the Institute started analyzing existing sighting reports and encoding about 30 report characteristics onto IBM cards for computer analysis.

Project Blue Book Special Report No. 14 was their massive statistical analysis of Blue Book cases to date, some 3200 by the time the report was completed in 1954. Even today, it represents the largest such study ever undertaken. Battelle employed four scientific analysts, who sought to divide cases into "knowns," "unknowns," and a third category of "insufficient information." They also broke down knowns and unknowns into four categories of quality, from excellent to poor. E.g., cases deemed excellent might typically involve experienced witnesses such as airline pilots or trained military personnel, multiple witnesses, corroborating evidence such as radar contact or photographs, etc. In order for a case to be deemed a "known," only two analysts had to independently agree on a solution. However, for a case to be called an "unknown," all four analysts had to agree. Thus the criterion for an "unknown" was quite stringent.

In addition, sightings were broken down into six different characteristics--color, number, duration of observation, brightness, shape, and speed--and then these characteristics were compared between knowns and unknowns to see if there was a statistically signficant difference.

The main results of the statistical analysis were:

  • About 69% of the cases were judged known or identified; about 9% fell into insufficient information. About 22% were deemed "unknown," down from the earlier 28% value of the Air Force studies, but still a very large fraction of the cases.
  • In the known category, 86% of the knowns were aircraft, balloons, or had astronomical explanations. Only 1.5% of all cases were judged to be psychological or "crackpot" cases. A "miscellaneous" category comprised 8% of all cases and included possible hoaxes.
  • The higher the quality of the case, the more likely it was to be classified unknown. 35% of the excellent cases were deemed unknowns, whereas only 18% of the poorest cases. This was the exact opposite result predicted by skeptics, who usually argued unknowns were poorer quality cases involving unreliable witnesses that could be solved if only better information were available.
  • In all six studied sighting characteristics, the unknowns were different from the knowns at a highly statistically signficant level: in five of the six measures the odds of knowns differing from unknowns by chance was only 1% or less. When all six characteristics were considered together, the probability of a match between knowns and unknowns was less than 1 in a billion.

Despite this, the summary section of the Battelle Institute's final report declared it was "highly improbable that any of the reports of unidentified aerial objects... represent observations of technological developments outside the range of present-day knowledge." A number of researchers, including Dr. Bruce Maccabee, who extensively reviewed the data, have noted that the conclusions of the analysts were usually at odds with their own statistical results, displayed in 240 charts, tables, graphs and maps. Some conjecture that the analysts may simply have had trouble accepting their own results or may have written the conclusions to satisfy the new political climate within Blue Book following the Robertson Panel.

When the Air Force finally made Special Report #14 public in October 1955, it was claimed that the report scientifically proved that UFOs did not exist. Critics of this claim note that the report actually proved that the "unknowns" were distinctly different from the "knowns" at a very high statistical significance level. The Air Force also incorrectly claimed that only 3% of the cases studied were unknowns, instead of the actual 22%. They further claimed that the residual 3% would probably disappear if more complete data were available. Critics counter that this ignored the fact that the analysts had already thrown such cases into the category of "insufficient information," whereas both "knowns" and "unknowns" were deemed to have sufficient information to make a determination. Also the "unknowns" tended to represent the higher quality cases, i.e. reports that already had better information and witnesses.

Project Blue Book's Official Conclusions

Project Blue Book stated that UFOs sightings were generated as a result of:

  • A mild form of mass hysteria.
  • Individuals who fabricate such reports to perpetrate a hoax or seek publicity.
  • Psychopathological persons.
  • Misidentification of various conventional objects.

As of April 2003, the USAF has publicly indicated that there are no immediate plans to re-establish any official government UFO study programs. [2] (

It should be noted that these official Air Force conclusions were directly contradicted by their own commissioned Blue Book Special Report #14. Psychological factors and hoaxes actually constituted less than 10% of all cases and 22% of all sightings, particularly the better cases, remained unsolved.

USAF current official statement on UFOs

From 1947 to 1969, the Air Force investigated Unidentified Flying Objects under Project Blue Book. The project, headquartered at Wright-Patterson Air Force Base, Ohio, was terminated Dec. 17, 1969. Of a total of 12,618 sightings reported to Project Blue Book, 701 remained "unidentified."

The decision to discontinue UFO investigations was based on an evaluation of a report prepared by the University of Colorado entitled, "Scientific Study of Unidentified Flying Objects;" a review of the University of Colorado's report by the National Academy of Sciences; previous UFO studies and Air Force experience investigating UFO reports during 1940 to 1969.

As a result of these investigations, studies and experience gained from investigating UFO reports since 1948, the conclusions of Project Blue Book were:

  • 1) No UFO reported, investigated, and evaluated by the Air Force has ever given any indication of threat to our national security.
  • 2) There has been no evidence submitted to or discovered by the Air Force that sightings categorized as "unidentified" represent technological developments or principles beyond the range of present day scientific knowledge.
  • 3) There has been no evidence indicating the sightings categorized as "unidentified" are extraterrestrial vehicles.

With the termination of Project Blue Book, the Air Force regulation establishing and controlling the program for investigating and analyzing UFOs was rescinded. Documentation regarding the former Blue Book investigation was permanently transferred to the Modern Military Branch, National Archives and Records Service, and is available for public review and analysis.

Since the termination of Project Blue Book, nothing has occurred that would support a resumption of UFO investigations by the Air Force. Given the current environment of steadily decreasing defence budgets, it is unlikely the Air Force would become involved in such a costly project in the foreseeable future.

There are a number of universities and professional scientific organizations that have considered UFO phenomena during periodic meetings and seminars. A list of private organizations interested in aerial phenomena may be found in "Encyclopaedia of Associations", published by Gale Research. Interest in and timely review of UFO reports by private groups ensures that sound evidence is not overlooked by the scientific community. Persons wishing to report UFO sightings should be advised to contact local law enforcement agencies.

(USAF USAF Fact Sheet 95-03) (


Blue Book’s explanations were not universally accepted, however, and critics--including some scientists--suggested that Project Blue Book was engaged in questionable research or, worse, pepetrating cover up.

Take for example, the many mostly nighttime UFO reports from the midwestern and southeastern United States in the summer of 1965: Witnesses in Texas reported “multicolored lights” and large aerial objects shaped like eggs or diamonds. The Oklahoma Highway Patrol reported that Tinker Air Force Base (near Oklahoma City) had tracked up to four UFO’s simultaneously, and that several of them had descended very rapidly: from about 22.000 feet to about 4.000 feet in just a few seconds; an action well beyond the capabilities of conventional aircraft. John Shockley—a meteorologist from Wichita, Kansas reported that, using the state Weather Bureau radar, he tracked a number of odd aerial objects flying at altitudes between about 6.000 and 9.000 feet. These and other reports received wide publicity.

Project Blue Book officially determined the witnesses had mistaken Jupiter or bright stars (such as Rigel or Betelgeuse) for something else.

Blue Book’s explanation was widely criticized as inaccurate. Robert Riser, director of the Oklahoma Science and Art Foundation Planetarium offered a strongly-worded rebuke of Project Blue Book that was widely circulated: “That is as far from the truth as you can get. These stars and planets are on the opposite side of the earth from Oklahoma City at this time of year. The Air Force must have had its star finder upside-down during August

A newspaper editorial from the Richmond News Leader opined that “Attempts to dismiss the reported sightings under the rationale as exhibited by Project Bluebook (sic) won’t solve the mystery ... and serve only to heighten the suspicion that there’s something out there that the air force doesn't want us to know about,” while a Witchita-based UPI reporter wrote (in a brief editorial aside) that “Ordinary radar does not pick up planets and stars.”

Hynek's Criticism

After what he described as a promising beginning with a potential for research, Hynek grew increasingly disenchanted with Blue Book during his tenure with the project, levelling accusations of indifference, incompetence, and of shoddy research on the part of Air Force personnel.

Hynek wrote that during Air Force Major Hector Quintanilla's tenure as Blue Book’s director, “the flag of the utter nonsense school was flying at its highest on the mast.” Hynek reported that Sergeant David Moody--one of Quintanilla’s subordinates, “epitomized the conviction-before-trial method. Anything that he didn’t understand or didn’t like was immediately put into the psychological category, which meant ‘crackpot’.”

Hynek reported bitter exchanges with Moody when the latter refused to research UFO sightings thouroughly, describing Moody as “the master of the possible: possible balloon, possible aircraft, possible birds, which then became, by his own hand (and I argued with him violently at times) the probable.”


  • Jerome Clark, ‘’The UFO Book: Encyclopedia of the Extraterrestrial’’, ISBN 1578590299

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