Project Blue Book

The claim

"The Air Force studied thousands of UFOs and couldn't explain hundreds of them."

Where the idea comes from

The Air Force ran Project Sign (1948), Project Grudge and then Blue Book to investigate reports after the 1947 wave.

What the evidence shows

1. Blue Book logged 12,618 sightings; 701 were left "unidentified".
2. Its conclusions: no report showed a threat to national security, no evidence of technology beyond ours, and no evidence that any sighting was an extraterrestrial vehicle.
3. The 1969 Condon Report from the University of Colorado, reviewed by the National Academy of Sciences, concluded further study was unlikely to advance science.
4. Critics, including Blue Book's own scientific adviser J. Allen Hynek, said many cases were dismissed too quickly.

What is still open

Unidentified usually means too little data. The 701 cases are mostly short sightings that can't now be re-examined.

Our verdict

Unproven Real unexplained reports, but no evidence of alien craft.

Sources

• Project Blue Book records (US National Archives)
• Project Blue Book (Wikipedia)

Checked 31 October 2026. Spotted a newer source? Tell us.