If you are a UFO or conspiracy nut, prepared to get tweaked. The FBI tosses documents up on its FBI Vault website all the time. One of the latest documents to hit that Vault site is circa 1950 and has to do with the infamous Roswell crash that many allege was a UFO crash.
The document was written by FBI investigator Guy Hottel, and recounts his talk with what the letter calls an “investigator for the Air Forces.” The name of the investigator has been redacted. The memo goes on to claim that the Air Force found a crashed UFO of a saucer shape that was 50-feet in diameter.
The memo goes on to say that the Air Force believed that the powerful radar it was operating in the area was the cause of the crash. Also noted was the collection of three humanoid bodies that were about three feet tall. Hoax or not, this is a very strange memo to turn up on a government website.