Documents / Case file
This is an initial Project Sign progress report dated April 1948, sent from Headquarters, Air Materiel Command at Wright-Patterson Air Force Base to the Chief of Staff, U.S. Air Force. It tabulates about 100 unidentified flying object reports received through February 1948, covering shape, size, number of objects, speed and exhaust trails. Dr. Irving Langmuir found the data insufficient for a positive identification. Headquarters judged that a low aspect ratio aircraft using boundary layer control could reproduce many of the reported characteristics.
From the source: Release of 2026-07-10 Incident: 1948, Various. This file contains an initial report from the Air Materiel Command regarding Project Sign. Project Sign was a 1948-1949 U.S. Air Force program to investigate the nature and origin of unidentified flying objects (UFO). The report details 100 UFO sightings from 1947-1948. The file also contains an article excerpted from “The Aeroplane,” an aviation-focused periodical magazine published between 1911 and 1968, titled “The Biology of the Flying Saucer.”
Incident loo SOb 30o 32 33a 33c 33d 3:Sf :S3g 34 35 36 37 38 39 40 - cor~FIDENTIAL Observer's Occupation Maneuvers Traffic Air Controller Bobbing up and down lot a~ated Climbing and de~oending Profe11or and Bead Mone or Aero Kn.gineering Lt, USAP Bone T/Sgt, USAF Jone 1,it.,Lt, USAF Bone PFC lone Capt, USA1 Kay have been turning Capt, Us.Ar None Col, Ky. State Police Kone Capt, USAF (Plight Not stated Leader •a 869) Unknown Mot stated Judge Bone Second Officer.Wavy Mone CAA Official Sot stated Pilot Kone Hungarian Peasants Not stated Constable Not stated Spiraled downward f'rom 5, 000 to 2,000 f't am then went upward at a 450 angle Weather Overcast High overcast Clear Overcast High acattered olouds Visibility unlimited. High scattered lfot stated High overcast with BIS High ecattered, vi ei bi lity unlimited Clear .Not stated Not stated Clear !lot atated Rot stated Clear ..,-.'! !lot stated a.tVU. ~ d Cumulus clouds
Case file, from the pursue collection. The PDF is mirrored here; the original link is above. 45 pages are in the text index: search them above, or from the library's search.