Documents / Report
This confidential progress report, dated 4 May 1953 and signed by L. W. Keith, went from the Navy's Photographic Interpretation Center to the Director of Naval Intelligence. It analyzes movies of unidentified objects filmed in Utah on 2 July 1952 and in Montana in 1950, which the U.S. Air Force had asked the Navy to interpret. Using plots, density readings and velocity estimates, the analysts judged the objects to be probably light sources that were disk shaped and moved at high speeds. They concluded the objects could not be identified as natural phenomena or commonly known man-made objects.
From the source:Release of 2026-08-07 Incident: 1950, 1952, Montana, Utah. 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.
“Expedition X”1 page
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Serial:
CONFIDENTIAL SECURITY INFORMATION
Subj: Interpretation of Movies of Unidentified Objects; progress report on
were 2457 and 378 mph respectively. These figures differ from those given in reference (c) and were computed from measurements obtained under more controlled conditions. Acceleration was determined from the formula :
$$
a = \frac {V f - V O}{T} \quad \mathrm {w h e r e :}
$$
$$
a = A c c e l e r a t i o n
$$
$$
V f = f i n a l v e l o c i t y
$$
$$
V O = \mathrm {i n i t i a l} v e l o c i t y
$$
$$
T = \mathrm {t i m e} = 1 / 1 6 \mathrm {s e c o n d}
$$
Since "g" is equal to 32.17 ft/sec $ ^{2} $ it was computed that:
Maximum acceleration = 21,168 mph/sec = 965 g
Minimum acceleration = 1,104 mph/sec = 50 g
Maximum deceleration = 32,448 mph/sec = 1479 g
Minimum deceleration = 272 mph/sec = 12 g
Velocity and acceleration determinations were also made from the Montana film. In this case, terrestial objects appeared in the film and were held to as control. Subsequently, the velocity and acceleration determinations are considered to be more reliable. On the assumption of (b) and (c) above the maximum and minimum velocities of the left object are 1374 and 361 mph respectfully. For the right object they are 1117 and 189 mph. Accelerations were computed as:
$$
\begin{array}{l l l l l} \mathrm {M a x i m u m a c c e l e r a t i o n m p h / s e c} & \mathrm {L e f t O b j e c t} \\ \mathrm {M i n i m u m a c c e l e r a t i o n m p h / s e c} & 1 4, 0 1 6 = 6 3 9 \mathrm {g} \\ \mathrm {M a x i m u m d e c e l e r a t i o n m p h / s e c} & 0 = 0 \mathrm {g} \\ \mathrm {M a x i m u m d e c e l e r a t i o n m p h / s e c} & 1 3, 1 8 4 = 6 0 1 \mathrm {g} \\ \mathrm {M i n i m u m d e c e l e r a t i o n m p h / s e c} & 0 = 0 \mathrm {g} \end{array} \quad \begin{array}{l l l l l} \mathrm {R i g h t O b j e c t} \\ 1 2 6 4 0 = 5 7 6 \mathrm {g} \\ 0 = 0 \mathrm {g} \\ 1 4 2 8 8 = 6 5 1 \mathrm {g} \\ 0 = 0 \mathrm {g} \end{array}
$$
The above determinations were made from a total of 322 measurements. It was noted that the acceleration and determinations were in multiples of 12.5 approximately. This may be of significance although no study has been conducted to determine this.
9. Velocity and acceleration were treated in sub-paragraph 8 above. Paragraph 2a indicates the controls used during this investigation. Report, from the pursue collection. The PDF is mirrored here; the original link is above. The text was read from the page images by GLM-OCR; expect the odd misread word. 23 pages are in the text index: search them above, or from the library's search.