Estimate of the Situation

The Estimate of the Situation was a document supposedly written in 1948 by the personnel of United States Air Force's Project Sign - including the project's director, Captain Robert R. Sneider - which explained their reasons for concluding that the extraterrestrial hypothesis was the best explanation for unidentified flying objects.

As late as 1960, USAF personnel stated that the document never existed. However, several Air Force officers, and one consultant, claim the report as being a real document that was suppressed. Jenny Randles and Peter Hough describe the Estimate as the "Holy Grail of ufology" and state that Freedom of Information Act requests for the document have been fruitless.

Though Sign investigated earlier UFO reports, historian David M. Jacobs writes that the highly publicized Chiles-Whitted UFO Encounter of July 24, 1948 "had a great impact at Sign". In that encounter, two experienced airline pilots claimed a torpedo-shaped object nearly collided with their commercial airplane. Sign personnel judged the report convincing and compelling, partly because the alleged object also closely matched the description of an independent sighting from The Hague a few days earlier.

According to Michael D. Swords, Sign personnel "intensely investigated" the Chiles-Whitted sighting for several months. Despite the lack of physical evidence, some Sign personnel judged this and other UFO reports quite persuasive, and concluded that UFOs could have only a non-earthly source.

Swords writes,

The project members reasoned that they had several dozen aerial observations that they could not explain, many of them by military pilots and scientists. The objects seemed to act like real technology, but their sources said they were not ours. The flying fuselage encounter [Chiles-Whitted] intrigued them. The Prandtl theory of lift indicated that such an odd shape can fly, but it would need some form of power plant advanced well beyond what we could build (e.g., nuclear)."

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