DOW-UAP-D097 — Project Sign Progress Report (1948)

45-page initial report from the Air Materiel Command regarding Project Sign — the first official U.S. government program to investigate UAP (1948–1949). Project Sign was the direct precursor to Project Grudge and Project Blue Book. The document reveals the Air Force's early deliberations about 'flying discs' and whether they might be of extraterrestrial origin. Released as PURSUE Release 04. Official document ID: DOW-UAP-D097.