The 'Estimate of the Situation'
According to Captain Edward Ruppelt, who later ran Project Blue Book, Project Sign staff wrote a top secret estimate arguing that some saucers were interplanetary craft. Chief of Staff General Hoyt Vandenberg rejected it for lack of proof, and copies were reportedly burned. Project Sign was replaced by the more dismissive Project Grudge in 1949.
The ledger
What the record shows, what people say, and the best explanation available so far.
What's documented
- Ruppelt described the estimate in his 1956 book.
- The shift from Sign to Grudge is on the record.
What's claimed
- Proof the Air Force privately concluded UFOs were alien.
Best explanation so far
No copy has ever surfaced. Whether it existed as described depends on secondhand accounts.
Check the sources
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