Navy Film Analysis: Great Falls and Tremonton (1953) – PURSUE Files

The U.S. Naval Photographic Interpretation Center’s memo on the 1950 Great Falls and 1952 Tremonton films, which found the objects inconsistent with natural phenomena or known aircraft

⚠ Note on validity: This is the Navy analysis the 1953 Robertson Panel rejected. The panel said the analysts used copies of the films and did not remove camera shake, and concluded the Tremonton objects were probably birds and the Great Falls objects probably jet aircraft.

Navy film analysis, 1953
Date	1953 (covering films from 1950 and 1952)
Films	Great Falls, Montana (1950); Tremonton, Utah (1952)
Agency	U.S. Naval Photographic Interpretation Center
Released	Release 05 (Aug. 7, 2026)
Files	1 (PDF)
Previously public?	Partly — its findings were summarized in Robertson Panel records and UFO literature; this memo and its charts appear newly published
Official releaseHistoricalDisputed

This memorandum documents how the U.S. Naval Photographic Interpretation Center analyzed two famous films: the 1950 Great Falls, Montana film and the 1952 Tremonton, Utah film shot by Navy photographer Delbert Newhouse. It includes the analysts’ assumptions, confidence level, tentative conclusions, recommendations, and charts comparing the objects’ brightness with their apparent size.^[1]

The records

DOW-UAP-D098, Film Analysis of Unidentified Objects, 1953

Open DOW-UAP-D098 (PDF) on war.gov →

This file contains a memorandum relating to the U.S. Naval Photographic Interpretation Center’s assessment of two films allegedly depicting unidentified airborne objects, captured in Montana and Utah in 1950 and 1952, respectively. The file documents the Center’s analytic process, assumptions that constrained its confidence level, tentative conclusions, and recommendations for future research. The Center assessed, generally, that the objects depicted in the film demonstrated characteristics that were inconsistent with those of natural phenomena or commonly known aerospace technologies. The memorandum documents the Center’s recommendation for a more well-resourced investigation to corroborate its presumptive findings, citing a lack of funding and personnel. The accompanying charts compare the film’s luminosity with the apparent angular size of the phenomena, using contemporary mathematical modeling and photogrammetric analysis techniques.
— Official PURSUE description

Analysis

The Navy’s view. The Center concluded the objects showed characteristics “inconsistent with those of natural phenomena or commonly known aerospace technologies,” and asked for a better-funded investigation to confirm its findings, citing a lack of money and staff.^[1]

The counter-view. In January 1953 the CIA-sponsored Robertson Panel reviewed this work and rejected it, arguing that brightness measurements from duplicate film were unreliable and that hand-held camera motion had not been removed. It favored birds for Tremonton and reflections from two F-94 jets known to be near the airport for Great Falls. Later analysts, including the Condon Report, considered the Great Falls case possibly unexplained.^[2]

New or previously released? Partly. The conclusions were known from Robertson Panel records and Ruppelt’s book; the memo with its charts appears to be newly published.

Released files

PURSUE ID	Title	Type
DOW-UAP-D098	Film Analysis of Unidentified Objects, 1953	PDF

References

^ U.S. Department of War (2026). PURSUE Release 05 (Aug. 7, 2026): DOW-UAP-D098, with official descriptions. war.gov/ufo.
^ Report of the Scientific Advisory Panel on Unidentified Flying Objects (Robertson Panel), January 1953.

Source: U.S. Department of War, PURSUE (Presidential Unsealing and Reporting System for UAP Encounters), war.gov/ufo. Official records are U.S. government works in the public domain; summaries and analysis on this page are by UFO UAP Wiki.