Edward James Ruppelt was a United States Air Force officer probably best known for his involvement in Project Blue Book, a formal governmental study of unidentified flying objects (UFOs). He is generally credited with coining the term "unidentified flying object", to replace the terms "flying saucer" and "flying disk" – which had become widely known – because the military thought them to be "misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO for short."
Captain Edward J. Ruppelt (left), head of Project Blue Book, at Wright-Patterson Air Force Base in March 1953
Project Blue Book was the code name for the systematic study of unidentified flying objects by the United States Air Force from March 1952 to its termination on December 17, 1969. The project, headquartered at Wright-Patterson Air Force Base, Ohio, was initially directed by Captain Edward J. Ruppelt and followed projects of a similar nature such as Project Sign established in 1947, and Project Grudge in 1949. Project Blue Book had two goals, namely, to determine if UFOs were a threat to national security, and to scientifically analyze UFO-related data.
Captain Edward J. Ruppelt (left), head of Project Blue Book, at the Wright-Patterson Air Force Base project office in March 1953
Hector Quintanilla became chief of Project Blue Book in August 1963
Project Blue Book, complete status reports (1 to 14), including Project Grudge data, and up to May 1955