Dolan points to 1948 Project Sign files weighing ‘vehicles from another planet’

Dolan calls a 245-page Project Sign collection in Tranche 5 one of the most important historical releases, saying it shows the US Air Force and Air Materiel Command privately treating UFO reports as a serious intelligence and defence issue in 1948. He quotes a memo attributed to Gen C. P. Cabell and says the material includes internal discussion of whether some reports could involve foreign technology and, explicitly, the possibility of “vehicles from another planet”, alongside recommendations for restrained public messaging.