USAF1948USAF Project Sign — Air Technical Intelligence Center, Wright-Patterson AFB

USAF Project Sign — "Estimate of the Situation" (1948, reconstruction)

Wright-Patterson AFB, Ohio (Air Technical Intelligence Center)

Summary

This memo is a historical reconstruction of the 1948 USAF Project Sign's top-secret intelligence assessment, known as the 'Estimate of the Situation.' It reportedly concluded that UFOs were of interplanetary origin, but Chief of Staff Hoyt Vandenberg rejected it due to insufficient proof and ordered its destruction. No original documents exist, and the record relies on later accounts.

Source

Project 1947 — historical reconstruction of the lost Sign estimate
via Project 1947 — reconstruction from Ruppelt and subsequent witnesses
Reconstruction by Project 1947 from Captain Edward J. Ruppelt's account and corroborating witness recollections; underlying USAF original is no longer extant.
No known restrictions on the reconstruction. Original USAF document destroyed circa 1948 on order of Chief of Staff Hoyt Vandenberg.

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