1947 · Wright Field, Ohio
Twining memo and Project Sign
When1947 – 1949
WhereWright Field, Ohio
Backing5 independent
Witnesses1 named
Evidenceofficial records, documents
In September 1947 Lt. Gen. Nathan Twining wrote that 'the phenomenon reported is something real and not visionary or fictitious', describing discs capable of extreme climb rates and evasive maneuvers. That memo launched Project Sign. In 1948 Sign's analysts reportedly sent up an 'Estimate of the Situation' concluding the saucers were interplanetary. Chief of Staff Hoyt Vandenberg rejected it and copies were said to be burned. The project was renamed Grudge and turned toward explaining sightings away.
Evidence, in date order (5)
- 1947Air Materiel Commanddocument1947-48 report on UFOs war.gov: Air Materiel Command report on UFOs, 1947–48 (Project Sign)
- 23 Sept 1947Lt. Gen. Nathan Twiningofficialmemo saying the phenomenon is 'something real' Wikipedia: Project Sign
- 1948Project Signdocument1948 progress report war.gov: Project Sign progress report, 1948
- 1949U.S. Armydocument1949 flying-saucer evaluation study war.gov: U.S. Army flying-saucer evaluation study, 1949
- Edward Ruppeltwitnessdescribed the Estimate of the Situation and its rejection Need to Know #15: the Estimate of the Situation
How plausible · High
The Twining memo and Sign's own reports are declassified.
- ●●Access Direct observation or instruments.
- ●●No gain sought Nothing to gain.
- ●●Character record Trained professionals.
- ●●Checkable details check out Released official records.
- ●●Fits the documented skeleton Fits the documented record.
- ●●Fits secrecy practice Fits documented secrecy.
Plausibility weighs how well an account fits where secrecy hides the documents by design, so missing records never count against it. Strength measures what is documented. Assessed 2026-10-23.
On the record
- The Twining memo of September 23, 1947 (declassified).
- Project Sign and Project Grudge are documented Air Force programs.Blue Book
- McCoy's personnel file (DOW-UAP-D180, PURSUE Release 07) places him at the head of AMC intelligence from Oct 1947 to Aug 1949; the file itself does not mention UFOs.
- The AMC memo reappears as exhibit 1 of the 2008 BAASS plan (DOW-UAP-D168).
Claims
The 'Estimate of the Situation' and its interplanetary conclusion, described by Blue Book chief Edward Ruppelt.Blue BooksecondhandSourced, unconfirmedEdward Ruppelt
Col. Howard M. McCoy was Chief, Intelligence Department, HQ Air Materiel Command, from 15 October 1947 to August 1949, the Sign and Grudge years; he also ran a classified 'Science Survey Office' that 'was abolished for unknown reasons shortly after' he left.Final personnel record of Col. Howard M. McCoy, USAF (1954)firsthandOn the recordDOW-UAP-D180
The 1947 AMC 'Flying Discs' memo was attached as exhibit 1 to the BAASS program plan for DIA in 2008.AMC Opinion Concerning 'Flying Discs' (Twining memo, 23 September 1947)BAASS Project Management Plan for DIA (2 December 2008)firsthandOn the recordDOW-UAP-D168
war.gov files on this case (3)
PDFAir Materiel Command Report on Unidentified Flying Objects, 1947-1948DOW · Release 05 · 1947-1948
PDFProject Sign Progress Report, 1948DOW · Release 04 · 1948
PDFUS Army-Flying-Saucer-Study 1949DOW · Release 03
In The picture
The crashes and the keepersAir Force General Twining wrote in 1947 that 'the phenomenon reported is something real'. Project Sign's analysts reportedly concluded the saucers were interplanetary, and copies were said to be burned. In 1953 the CIA's Robertson Panel recommended debunking. When Blue Book closed, a memo noted that reports touching …
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People and organizations
Wright-Patterson AFB & 'Hangar 18' orgCol. Howard M. McCoy personAMC Opinion Concerning 'Flying Discs' (Twining memo, 23 September 1947) documentBAASS Project Management Plan for DIA (2 December 2008) documentFinal personnel record of Col. Howard M. McCoy, USAF (1954) documentEstimating Flight Characteristics of Anomalous Unidentified Aerial Vehicles documentThe new science of Unidentified Aerospace-Undersea Phenomena (UAP) document
Threads · click one to see it on the board
Sources
- Wikipedia: Project Sign
- war.gov: Project Sign progress report, 1948
- war.gov: Air Materiel Command report on UFOs, 1947–48 (Project Sign)
- war.gov: U.S. Army flying-saucer evaluation study, 1949
- Need to Know #15: the Estimate of the Situation
- war.gov: DOW-UAP-D180, Final Personnel Record for McCoy, Howard M., USAF, 1954