17 December 1969 / T110
Project Blue Book terminated; defense reporting did not disappear
Washington, D.C.; Wright-Patterson Air Force Base, Ohio
Witness account
The Air Force ended Project Blue Book after reviewing its record and the Condon study. The National Archives preserves the case files and reports a total of 12,618 sightings, of which 701 remained classified as unidentified. Those totals describe the program’s administrative categories, not a census of alien craft or an error-free scientific sample.
Public record
The public rationale found no demonstrated national-security threat, unknown advanced technology or extraterrestrial vehicles in the investigated material. A separate 20 October 1969 Bolender memorandum distinguished defense-significant reporting channels from the Blue Book system. Closure of a public-facing UFO investigation therefore should not be rewritten as a pledge that military personnel would cease reporting every unusual aerial observation.