DOW-UAP-D102 — Tremonton Film: Conflicting Technical Assessments
This Project Blue Book file preserves Delbert C. Newhouse’s account and film submission from the 2 July 1952 Tremonton incident. Newhouse said the sky supplied no fixed reference for estimating distance, size, altitude, or speed. Navy analysts favored an unidentified light-source interpretation under disputed assumptions, while later reviews considered balloons, birds, insects, and mirage; one 1956 study remained inconclusive before an Air Force memo adopted a seabird explanation.
- File
- Document · Release 06
- Date
- July 2, 1952
- Location
- Tremonton, Utah
- Extent
- 156 pages
Search This File
Probed Assessment
A long case file that preserves the witness statement, film-custody record, and competing technical assessments, with critical distance and camera-motion uncertainties left unresolved by the imagery.
Key takeaways
- Newhouse reported about ten or twelve objects near Tremonton and filmed them with a handheld 16 mm camera.
- He explicitly said the empty sky provided no reference point for estimating speed, size, altitude, or distance.
- The Navy light-source and disk-size conclusions depended on an arbitrary five-mile distance and other motion assumptions, and its report acknowledged incomplete corroboration and resource limits.
- Balloon specialists thought pillow balloons resembled the film, although one expert dissented and no Navy release was documented near the location.
Why it matters
The file shows how the same motion-picture evidence produced sharply different official interpretations and makes the assumptions behind its strongest numerical and shape claims inspectable.
Corroboration
The released file directly supports Newhouse’s submission details, the custody correspondence, and the stated contents of each technical review. It does not independently establish the objects’ distance, physical dimensions, linear velocity, material, or identity, and repeated copies of the witness account are not separate corroboration.
Open questions
- • Which generation of the film was used in each surviving analysis and how much detail was lost through duplication?
- • Can the original camera motion be reconstructed well enough to test the historical velocity calculations?
- • What surviving comparison films or measurement records underlie the Air Force’s final seabird judgment?
Probed separates this editorial assessment from the source claims below. It summarizes what the released artifact supports; it is not independent verification.
Official Description from War.gov
This document records the Project Blue Book investigation and subsequent assessments of an incident near Tremonton, Utah, on July 2, 1952. Project Blue Book was a 1952-1969 U.S. Air Force program to investigate the nature and origin of unidentified flying objects (UFOs). The file describes the Air Force’s assessment of the principal witness, Delbert C. Newhouse, a U.S. Navy Warrant Officer specializing in photography, as honest and reliable, and as an expert with more than 1,000 hours of aerial-photography experience. Newhouse reported observing 12 to 14 reflective objects and recorded the event on color motion-picture film using a handheld Bell & Howell Auto Master camera. The file reflects an evolving Air Force assessment of the imagery over several years. Early documentation considered several possible explanations, including sunlight reflecting from birds or balloons, and a mirage effect, and did not identify the objects conclusively. Later assessments became more confident that the objects were seabirds reflecting sunlight, citing identifiable seabirds and similar films showing seabirds as bright points of light under comparable conditions. However, the film’s limited detail and lack of fixed reference points prevented reliable determination of the objects’ distance, size, altitude, or linear speed from the film alone. AARO Comment: The file contains conflicting references to the film format. Several documents describe a 35mm film, while contemporaneous submission documentation identifies the original as a 50-foot roll of processed 16mm Kodachrome color motion-picture film recorded with a handheld Bell & Howell Auto Master camera. Newhouse reported exposing approximately 30 feet of the roll during the incident and using the remaining film later that day to record unrelated mountain scenery in Idaho. Other records show that 35mm positive and negative duplicate blowups were produced from the original 16mm material. The file also indicates that the original film was duplicated for preservation, citing its deteriorating condition. The footage retained by the National Archives and Records Administration and presented in this collection as DOW-UAP-PR159 is a digitization of a 16mm print.
Preserved verbatim as source metadata. This wording is separate from Probed’s file-specific description and assessment.
File Context
Related entities
Tracker findings
Newhouse dates and locates the Tremonton filming
Newhouse’s submission places the observation about seven miles north of Tremonton at 1110 on 2 July 1952 and identifies a handheld 16 mm camera operating at 16 frames per second.
Newhouse reports a rough group moving west
Newhouse reported about ten or twelve objects milling in a rough formation and proceeding westward.
The witness had no fixed measurement reference
Newhouse said the empty sky supplied no reference point, preventing him from estimating the objects’ speed, size, altitude, or distance.
The brittle original was duplicated for preservation
The Naval Photographic Interpretation Center reported that the Utah film was dry and brittle and duplicated it to preserve the footage.
Navy densitometry used a duplicate and partial-image readings
The Navy report cautioned that its densitometry could not measure whole objects at maximum image size and was performed on a duplicate of a copy, raising a possible image-burnout problem.
Navy analysts favored an unidentified light-source interpretation
The Navy analysis team’s majority opinion treated the images as light sources and said it could not identify them as natural phenomena or commonly known man-made objects; the file does not establish that interpretation independently.
The disk and size result depended on assumed distance
The Navy report’s apparent oblate or disk-shaped description and 98-foot maximum size were calculation results conditioned on an assumed five-mile distance, not a directly observed object shape or dimension.
Velocity calculations rested on three explicit assumptions
The Navy velocity calculation assumed a steady camera, motion perpendicular to the optical axis, and an arbitrary five-mile distance.
The Navy report acknowledged no corroboration and limited resources
The Navy report stated that its findings had not been corroborated and that the investigation was limited by equipment, money, and personnel.
Balloon specialists agreed broadly but one expert dissented
Balloon specialists who repeatedly viewed the film generally thought the objects closely resembled pillow balloons, while General Mills’ J. R. Smith considered them too bright and fast for that explanation.
Astronomers challenged the Navy brightness method
An internal Air Force memorandum said two astronomers judged the Navy’s image-brightness method wrong, undermining the report’s conclusions and motivating proposed comparison tests.
Baker found no single natural hypothesis sufficient
After considering insects, mirage, camera artifacts, and birds, Baker wrote that the evidence was contradictory and no single proposed natural hypothesis completely accounted for the objects.
A later Air Force memo adopted the seabird explanation
A June 1956 Air Force memorandum said a later blind review identified the images as bird reflections and asserted there was little reasonable doubt that the objects were seagulls; this was an agency conclusion rather than independent proof.
Release provenance
- Release
- Release 06
- Official ID
- release-06-file-001-dow-uap-d102-project-blue-book-file-on-tremonton-film-utah-1952
- Cleared
- Sep 18, 2026
Referenced Timeline
Balloon specialists review the film
Flues convened Office of Naval Research, university, and General Mills specialists in Minneapolis to compare the film with pillow-balloon behavior.
Tremonton observation filmed
Newhouse’s statement places the observation and filming near Tremonton, Utah, at 1110 local time.
Newhouse submits the processed film
Newhouse forwarded a 50-foot roll of processed 16 mm color motion-picture film to Hill Air Force Base.
Air Force opens pillow-balloon inquiry
A. G. Flues contacted Malcolm Ross to ask whether pillow-balloon releases could account for the incident.
Navy final analysis reports an unidentified light-source interpretation
The Naval Photographic Interpretation Center issued its final analysis while documenting significant assumptions and limitations.
Navy reports custody of duplicate materials
The Navy center said it had never held the original and listed the 16 mm and 35 mm copies in its custody.
Baker completes an inconclusive photogrammetric review
R. M. L. Baker Jr. completed a review that tested several natural alternatives without reaching a definite conclusion.
Air Force memorandum adopts the seabird explanation
The Air Force memorandum summarized its later view that bird reflections, specifically seagulls, explained the bright spots.
Source Claims
Claims are attributed to the released source and remain distinct from Probed’s assessment and tracker findings.
Newhouse’s submission places the observation about seven miles north of Tremonton at 1110 on 2 July 1952 and identifies a handheld 16 mm camera operating at 16 frames per second.
Place: About 7 miles north of Tremonton, Utah on U.S. Highway No . 30S. Time: 1110 Wednesday 2 July 1952. Camera: B&H Automs.ster, magazine load, 3 11 telephoto lens, 16 frames per second. Handheld.
Newhouse reported about ten or twelve objects milling in a rough formation and proceeding westward.
There was a group of about ten or twelve objects -that bore no relation to anything I had seen before -milling about in a rough formation and proceeding in a westerly direction.
Newhouse said the empty sky supplied no reference point, preventing him from estimating the objects’ speed, size, altitude, or distance.
There was no reference point in the sky and it was impossible for me to make any estimate of speed, size, altitude or distance.
Newhouse reported that one object reversed course; he then held the camera still while it crossed the field of view several times.
Toward the end one of the objects reversed course and proceeded away from the main group. I held the camera still and allowed this single one to cross the field of view
The submitted evidence was described as one 50-foot roll of processed 16 mm color motion-picture film.
One (1) fifty-foot roll of processed 16mm color motion picture film
The Naval Photographic Interpretation Center reported that the Utah film was dry and brittle and duplicated it to preserve the footage.
The film exposed in Utah ie i n very poor condition; dry, brittle, a nd with a tendency to break. After initial viewing, duplication of the film was peri"ormed in order to preserve the f~
The Navy report cautioned that its densitometry could not measure whole objects at maximum image size and was performed on a duplicate of a copy, raising a possible image-burnout problem.
It is understood that normal procedure would be to read the entire object. This was illlpossible with the equipment on hand. In addition the film, with which this investigation was conducted, is a duplicate of a copy.
The Navy analysis team’s majority opinion treated the images as light sources and said it could not identify them as natural phenomena or commonly known man-made objects; the file does not establish that interpretation independently.
It is the majority opinion of the group conducting this analysis that these images are light sources. This will explain the non-blinking and variations i n luminosity -but not the velocity or acceleration faciors.
The Navy report’s apparent oblate or disk-shaped description and 98-foot maximum size were calculation results conditioned on an assumed five-mile distance, not a directly observed object shape or dimension.
The shape of the objects appears to be oblate or disk shaped, color; blue-white, and maximum a nd minimum size; 98 and 16 feet. The size is baaed on the assumpt ion that the objects are five miles from the observer.
The Navy velocity calculation assumed a steady camera, motion perpendicular to the optical axis, and an arbitrary five-mile distance.
In determining the velocity of the objects three assumptiorus were ma.de: a. The camera was held steady during Part III of the film. b. The objects were moving perpendicular to the optical axis, and c. The objects were five miles from the camera.
The Navy report stated that its findings had not been corroborated and that the investigation was limited by equipment, money, and personnel.
As to the resuJ.ts of the investigations being reported, no attempt was made tooorroborate the ppinions presented. Because of the lack of proper e ui ment, money and e onnel the in on was 1 .
A December 1952 inquiry found that two Office of Naval Research personnel thought the objects were pillow balloons, but also recorded that the Navy had released none near Tremonton at the relevant time.
it was his opinion, as well as that of Lt Lewis, ONR, that the objects photogr~phed were pill-0w balloons. However, Lt Ross said that the Navy had not .f:el~ased any pillow balloons in or near that area at that time.
Balloon specialists who repeatedly viewed the film generally thought the objects closely resembled pillow balloons, while General Mills’ J. R. Smith considered them too bright and fast for that explanation.
It was the consensus of opinion that the objects resembled pillow balloons 1n flight very closely and did nothing that pillows would not do in similar circumstances. J. R. Smith was the least convinced of this hypothesis
The balloon-review group placed little confidence in angular-velocity computations because they depended on the assumption that Newhouse kept the camera still.
None of the persons present placed much faith in the computations of angular velocity, since all were predicated upon Newhouse's holding the camera still.
A proposed Air Force public statement said the images were too poorly defined to identify their form or substance and that the absence of reference points prevented distance, size, and linear-speed estimates.
Images appearing on the film are nonsufficiently defined to permit identification or determination of form or substance and should have been caused by unknown objects or undetermined known obJects. The absence of any reference ooints, even clouds, in the bac·ground
An internal Air Force memorandum said two astronomers judged the Navy’s image-brightness method wrong, undermining the report’s conclusions and motivating proposed comparison tests.
It was brought out by two astronomers who heard a Navy briefing on the analysis of the movies that the method used to measure the brightness of each spot was wrong, therefore, the results of the entire study were wrong.
A March 1954 Navy letter stated that its photographic interpretation center had never possessed the original film and did not know its whereabouts.
It is advised that this Center bas never had possession of the original film and does not have in:formation concerning its whereabouts.
Baker’s 1956 review found that the measured angular velocity could fit soaring birds at less than a mile and a single bird within roughly 1,000 feet.
The relative angular velocity might be canpatible with soaring bird speeds at distances at less than one mile, the angular velocity ot the single objeot coul.d be attributed to a bird within about one thousand feet.
After considering insects, mirage, camera artifacts, and birds, Baker wrote that the evidence was contradictory and no single proposed natural hypothesis completely accounted for the objects.
The evidence remains rather contradictory and no si:cgle hypothesis of a natural phenomenon yet suggested seems to completely account for the UFO involved.
A June 1956 Air Force memorandum said a later blind review identified the images as bird reflections and asserted there was little reasonable doubt that the objects were seagulls; this was an agency conclusion rather than independent proof.
A recent analyaia of the Newhouae film, male by Air .Force photo apeclali•t• totally unaware of the previous hiatory o! thi• case, yielded the opinion that the bright spote of light on the film were bird refiecti0t1s in the strong aunlight.
A Hill AFB telegram recorded one weather balloon released at each of 0200 and 0800 on 2 July 1952 and reported trajectory and wind details, without identifying the filmed objects as either balloon.
PROJECT BLUE BOOK 1 WEA BLN EA RELSD 0200 AND 0800 2 JUL 52 TRAJECTORY SW TO NE THENCE W TO E THENCE NW TO SE DURING ASCENSION WINDS GENLY FR W SPEED 10-12 KNOTS
Source Material & Evidence
Research Map
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