The Washington Carousel is one of the most widespread UFO sightings. The Washington Carousel took place from July 12 to 29, 1952 in Washington, DC, started after newspaper coverage of a UFO sighting at Washington Airport. The Washington carousel provoked a reaction from the leadership of the US Air Force, the White House administration and personally US President Harry Truman. The phenomenon was widely covered by news agencies, including the Washington Post, New York Times. To calm public opinion and answer media questions, and also hoping to dampen public interest in the UFO topic, a press conference was held at the Pentagon on July 29, 1952. It was attended by Air Force Intelligence Director Major General John Samford and USAF Director of Operations Roger Ramey.
It was the largest Pentagon press conference since World War II. During the press conference, Samford said that objects observed over Washington can be explained by air disturbances (such as fireballs or meteors). Samford also stated that UFO sightings on radar screens could be explained by air reversal. In addition, Samford argued that the observed targets were not made of solid materials and therefore did not pose any threat to national security. Asked if the Air Force is registering similar incidents elsewhere, Samford admitted that there have been "hundreds" of such contacts, but the fighters raised on alert are "useless." Ruppelt assessed the results of the press conference positively, as he put it: “In getting the press off our backs”.
Since the Air Force press conference, eyewitnesses, UFO researchers and military pilots have continued to criticize Samford's explanations. Captain Ruppelt noted that Major Fournet and Lieutenant Holcomb, who were involved in the events, disagree with the Air Force's explanation. An INS article stated that the United States Weather Bureau also disagrees with the temperature inversion hypothesis. Their spokesman stated that "such an inversion is usually represented on the radar screen as a steady line, rather than as a single object seen on airport radar." In addition, when he was able to familiarize control tower personnel at Washington National Airport with the results of the press conference, Ruppelt said, no one agreed with the BBC's explanation.
The overwhelming number of reports of UFO sightings in 1952 caused alarm in both the United States Air Force and the CIA. Both organizations believed that enemy states could deliberately flood the American media with false UFO reports in order to create widespread panic and thereby create favorable conditions for an attack on the United States. On September 24, 1952, the CIA's Office of Scientific Intelligence (OSI) issued a memorandum for CIA Director Walter B. Smith. It stated that: "The flying saucers situation … has national security implications … causes public concern … creates a threat of mass hysteria and panic" (Peebles, Curtis, Watch the Skies !: A Chronicle of the Flying Saucer Myth. Berkley Books, 1994. ISBN 0-425-15117-4).
The result of this memorandum was the creation in January 1953 of the Robertson Group. Physicist Howard Percy Robertson led a group of distinguished scientists who spent four days reviewing the "best" UFO sightings collected by the Blue Book Project. The group dismissed almost all UFO sightings and ruled that they were not unusual and did not pose a threat to US national security. The group recommended that the Air Force and Project Blue Book take steps to "give UFO information special status." After this talk, Project Blue Book rarely received publicity.