PURSUE Record — FBI 62-HQ-83894 — Kenneth Arnold Cascade sighting (June 24, 1947): Federal Bureau of Investigation · Mount Rainier and the Cascade Range, Washin

FBI case file 62-HQ-83894 is a declassified PDF released by the Federal Bureau of Investigation under PURSUE Release 01 on May 8, 2026. It documents the Bureau's contemporaneous handling of Kenneth Arnold's June 24, 1947 report of nine high-speed objects observed near Mount Rainier and the Cascade Range in Washington State — an incident most frequently cited as the starting point of the modern UAP era in the United States. This is a primary-source government record covering a specific witness account and the institutional response to it, not a retrospective summary or analytical report.

What this record contains

The single-part PDF carries FBI case number 62-HQ-83894. Per the official description accompanying the PURSUE release, the file includes Arnold's own statement, follow-up interviews conducted by Bureau personnel, and contemporary news clippings. Arnold was a civilian pilot from Idaho who, while conducting an aerial search for a downed C-46 transport aircraft, observed what he described as nine crescent-shaped objects flying at high speed in formation past Mount Rainier on June 24, 1947. Press coverage in the days following the report popularized the phrase "flying saucer" — a term attributed to journalists' characterizations of Arnold's account rather than to his own wording — and that framing entered the public vocabulary almost immediately.

The PURSUE catalogue lists one releasing agency (the FBI), one file part, and classifies the document as a declassified PDF. Beyond the description blurb, the public-facing metadata does not enumerate page count, the original classification level at time of creation, or the specific dates on which follow-up interviews were conducted. The public release does not include additional granular detail for this record beyond what is noted above.

Historical & documentary context

In mid-1947 the FBI had no standing mandate to investigate aerial phenomena. Institutional responsibility for that area would later be formalized through Air Force Project Sign (1947), Project Grudge (1949), and ultimately Project Blue Book (1952–1969). The Arnold sighting arrived in an unsettled moment: the Army Air Forces had only just separated into an independent service, Cold War anxieties about Soviet airspace incursion were acute, and no agreed federal protocol existed for routing a civilian UAP report through government channels. The Bureau's involvement in this case reflects that institutional ambiguity — agents fielded statements and shared information with Army intelligence, but UAP investigation was not treated as a core FBI function, and case-handling practices were improvised rather than systematic.

The 1947 evidentiary environment also means this file is entirely witness-derived. No onboard sensor record, radar track, or photographic documentation is associated with the incident in the public release. The file's evidentiary weight rests on the quality and consistency of Arnold's statement and the contemporaneous interviews — the same factors that have sustained historiographic interest in this case for nearly eighty years.

What this does and does not prove

What the record documents is that a credentialed civilian pilot filed a formal account with federal authorities, that the Bureau opened a numbered case file, and that agents gathered corroborating materials including press coverage. What it does not document is any explanation for what Arnold observed. The PURSUE release makes no determination of origin, nature, or identity for the reported objects. In this context, "unresolved" means the case has not been accounted for to an investigative standard — it does not constitute confirmation that something anomalous occurred. The file is evidence of the report and of the institutional response to it; it is not, and does not claim to be, anything beyond that.

How it fits PURSUE Release 01

This record is part of the FBI historical archive strand within PURSUE Release 01 — a 162-document release that also includes Department of War contemporary mission reports and NASA archive imagery. Incorporating 1947-era Bureau files alongside modern sensor data was a deliberate choice, signaling that the release was designed to surface foundational case material rather than restrict itself to recent records. The full FBI archive contribution to Release 01 is catalogued on the SkyLens UAP files page, and broader PURSUE coverage on this blog addresses the Department of War and NASA strands of the same release in parallel context.

Editorial note: This analysis is independent commentary on a publicly released document. The original record, source links, and full release metadata are catalogued on the SkyLens UAP files page alongside every other case in the PURSUE Release 01 set.