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.”
, .DENTIAL e Incident 110, 84 color Sb1Jm7 Ship, Road lot ltated lore~ le11 SbJ-111. 85 Bot 1tated Reseabled the D5U•l. Jot 1tated lot 1tated 86 Not 1tated lot atate(! IOt ltated lot stated 87 Jot S1t&ted Bot stated lot ata.ted lot atated 88 lot stated 1lying di ec (not ao tual ly deaoribed aa being ot thi• aha.pe) )lot 1t1.ted lot atated Ro\lDd di,o ahaped object 50-60 rt. diameter bot at&ted Refleote4 light Unitonn with no protu berano•• euoh •• wing• of an airplane Hot atatad Bot 1tt.t1d Light lot atated Not stated looe 92 Silver lot ,tated S-11 lloli ata.ted 94 Bluish center Appeared to be a ·.rlth rod on its edgH !ot atatad lot 1tated di10 Reaembled ~ shooting at~r; however. ob- aervera not oertain Not stated Not etated Not ,tated 95 Not stated Not stated Kot stated Bot stated 96 Not st:i.ted Hot etated Not stated Not atated 91 Flaah of light Kot atat•• Hot stated Hot atated 98 Bright light Ahaoat round or perhaps oval or aauoer-ahaped 2ti-30 miles diametor lot etated 99 Shining Brightly ehining object with long td 1 lot atated Bot atated 100 Wot ,tated lot atated !lot stated NND 927545
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.