Project Sign Progress Report, 1948

U.S. Department of War · 1948 · 45 pages · text from the file's own layer

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.”

Open the PDF at page 6 Original source ↗

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56 6 Jul 47 2945 1-10 Gi-oan4
57 20 lul 47 0015Z Abou-c! the BUl'aeo (at sea
one hr. troa 874ne7, Autft11a) 1 Boat
58 4 Aug 47 BYeJWII Bethel, Alaska 1 Ail"
59 14 Se»t 47 055ae1T Reeter Ialand 1 ill'
60 10 Jul 47 1000 Oor4707, Canac!a 1 OPOUDCS
61 8 Sept 47 22:,0 Salt Lllce CltJ, Unb 12 Ground
62 8 Sept 47 22:S0~:S00 Salt Like Cit7, Utah 5 Sl'0'QP8 Ground
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6:s 29 JuJ. 47 1205 can,on 1em, llontana l Ol'om:ad
64 19 Aug 47 2130 Tv1n Jalll, Idaho A.pprox.
55. Ol'oun4
65 2 Jun 47 lot stated Rehoboth Beaoh, Delevan 1 Ground
66 10 Aug 47 2100 811Yer 8pr1.ngt, Ohio l Ol'ound
67 llJ. Aug 47 1600 Placemlle, lalitornia 1 Ground
68 24 Jun 47 Hot 1tattd Cuoa4e lountaiJ:aa,
Pwtlan4, 01-egon 6 Ground
69 6 Aug 47 22,0-2245 Ph1l.a4elph1a, Pa. 1 Ol'Ound
70 6 iug 47 1045 Ph1lt4elph1a, Pa. l Ol'oand
71 8 Oot 47 lot 1tatecl Laa Vega■, leYa4a 1 Ol'Ound
72 lot atate4 Jot 1tatec1 Port R1obardl0J1, Alllb 1 Ol"oand
7J 4 Aug 47 1600 Boston (101111e1 n) •••· 2 A1r
74 24 .JW'l 47 App. 1500 •t. A~IU, ftlh!ngton lot stated Ground
75 1, Aug 47 1300 saote Rl•er aaix,on, Idabo l Ground
76 1:5 Aug 47 Jlornlng Salaon Du, Ic!aho 2 Ornnd
77 :S 11117 47 1s,~ South BrookYille, Dine 10 Gl'O\IDl2
78 :,o Jun ~7 0910 JIST Oran4 ClllQ'on, AP1aoaa 2 ill'
79 Apr 47 1100 ES! R1oba0nd, V11"g1n.1a 1, other■ on Grcnmd
other ooou1ona

Cases discussed

The Kenneth Arnold Sighting 1947
Incident 17, 24 Jun 47, Mt. Rainier, Washington, 9 objects seen from air
The Maury Island Incident 1947
Incident 43, 29 Jun 47, 175-250 ft diameter, inverted saucer, harbor pilot
United Air Lines Flight 105 Sighting, Emmett, Idaho 1947
Incident 10, Capt, United Airlines, horizontal flight at airline speed
Twin Falls saucer hoax 1947
Incident 64, 19 Aug 47, Twin Falls, Idaho
Snake River Canyon Disc: The A.C. Urie Sighting 1947
Incident 75, Snake River Canyon, Idaho, trout farm operator
Muroc Army Air Field disc sightings 1947
Incidents 1 to 1e, 8 Jul 47, Muroc Air Field, Area 113, Rogers Dry Lake
The 1947 Flying Disc Craze: America's First Flying Saucer Wave 1947
Tabulation of many June to August 1947 flying disc reports across the US
The Mantell UFO Incident 1948
Incident 33, 7 Jan 48, Godman Field, Ky., Capt USAF Flight Leader

About this file

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.