Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341

NARA Report landing 1940s Official link verified

Summary

AI-assisted summary — not an official document and not authoritative. It condenses the machine-extracted text; the original is the only authoritative source. Generated by summary:claude-opus-4-8@v1; last reviewed 2026-06-02.

The August 1949 U.S. Air Force technical report of Project Grudge, the successor to Project Sign and a predecessor of Project Blue Book in the U.S. military's investigation of unidentified flying objects. Held in National Archives Record Group 341.

Project Grudge was a U.S. Air Force study of unidentified flying objects that succeeded Project Sign in 1949. This record is its August 1949 technical report, "Unidentified Flying Objects — Project GRUDGE," held in National Archives Record Group 341 (Records of Headquarters U.S. Air Force). Grudge generally attributed UFO reports to conventional causes such as misidentifications of conventional objects, balloons, and other explainable phenomena. It preceded Project Blue Book, which ran from 1952 to 1969. The archive links to the National Archives Catalog entry for this report and does not host the document.

Common questions

What was Project Grudge?
It was a U.S. Air Force study of unidentified flying objects that succeeded Project Sign in 1949 and preceded Project Blue Book.
What is this record?
It is Project Grudge's August 1949 technical report, "Unidentified Flying Objects — Project GRUDGE," held in National Archives Record Group 341.
How did Project Grudge characterize UFO reports?
It generally attributed them to conventional causes such as misidentifications of ordinary objects and balloons.

Source & Classification

Record metadata

Record type
Report landing
Decade
1940s
Review status
published
Publication status
published

Official source link

https://catalog.archives.gov/id/461456800

Documents are linked to their official source pages, with a local preservation copy of the public-domain U.S.-government document where available; the official source is authoritative. Videos are linked, not hosted. Copyright and license notes are recorded per source.

Cite this record

National Archives and Records Administration (NARA). "Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341". 1940s. Official source: https://catalog.archives.gov/id/461456800. Cataloged by the independent UAP Records Archive (not an official or government source): https://uap-archive.org/uap/records/nara-rg341-project-grudge-technical-report-1949/.

APA

National Archives and Records Administration (NARA). (1940s). Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341. https://catalog.archives.gov/id/461456800

MLA

National Archives and Records Administration (NARA). "Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341." 1940s, https://catalog.archives.gov/id/461456800.

Chicago

National Archives and Records Administration (NARA). "Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341." 1940s. https://catalog.archives.gov/id/461456800.

BibTeX

@misc{uaprecords_nara-rg341-project-grudge-technical-report-1949,
  title  = {Technical Report "Unidentified Flying Objects, Project GRUDGE," August 1949 — NARA Record Group 341},
  author = {National Archives and Records Administration (NARA)},
  year   = {1940s},
  howpublished = {Official source: https://catalog.archives.gov/id/461456800},
  note   = {Cataloged by the independent UAP Records Archive — not an official or government source},
  url    = {https://uap-archive.org/uap/records/nara-rg341-project-grudge-technical-report-1949/}
}

Embed this record

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<figure style="max-width:600px;margin:0;">
  <a href="https://uap-archive.org/uap/records/nara-rg341-project-grudge-technical-report-1949/"><img src="https://uap-archive.org/og/records/nara-rg341-project-grudge-technical-report-1949.png" alt="Technical Report &quot;Unidentified Flying Objects, Project GRUDGE,&quot; August 1949 — NARA Record Group 341 — UAP Records Archive" width="600" style="width:100%;height:auto;border:0;" loading="lazy"></a>
  <figcaption style="font-size:13px;line-height:1.5;">National Archives and Records Administration (NARA). &quot;Technical Report &quot;Unidentified Flying Objects, Project GRUDGE,&quot; August 1949 — NARA Record Group 341&quot;. 1940s. Official source: https://catalog.archives.gov/id/461456800. Cataloged by the independent UAP Records Archive (not an official or government source): https://uap-archive.org/uap/records/nara-rg341-project-grudge-technical-report-1949/. <a href="https://uap-archive.org/uap/records/nara-rg341-project-grudge-technical-report-1949/">View record →</a></figcaption>
</figure>

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Evidence

License note (source-level)

U.S. Government records (U.S. Air Force), generally public domain under 17 U.S.C. §105; held in NARA Record Group 341 (Records of Headquarters U.S. Air Force (Air Staff)). Referenced via the official National Archives Catalog entry only; not self-hosted by this archive.

Archivist note

This record is the August 1949 U.S. Air Force technical report titled “Unidentified Flying Objects — Project GRUDGE.” Project Grudge was an early U.S. Air Force study of UFO reports and a predecessor to Project Blue Book; the report is held in National Archives Record Group 341 (Records of Headquarters U.S. Air Force (Air Staff)). This archive links to the official National Archives Catalog entry and does not self-host the document.

Uncertainty / Limits

Archive state (this release)

Record status
Official link verified
Review status
published
Publication status
published
Archive URL
Not archived in U3
Local copy
Not stored in U3
Summary
Not published
Translation
Not published
Added to archive
Last revised
· 1 revision

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Translation

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