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Within Military Skies

What Did Two Airmen See South of Cheyenne?

Two Warren airmen reported four unusual objects in clear weather, but missing range data and late reporting left the case unresolved.

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On this page

  • The witnesses and five minute observation
  • Why balloons were considered but not confirmed
  • What the missing distance and tracking data prevent US knowing
Preview for What Did Two Airmen See South of Cheyenne?

Introduction

The May 1955 sighting south of Cheyenne is one of the more substantial UFO reports associated with Wyoming because it involved two US Air Force airmen, was formally investigated by Project Blue Book, and could not be conclusively explained. At the same time, it is also a good example of why an official “unidentified” classification should be treated cautiously. The witnesses described four unusual objects during a roughly five-minute observation, but crucial details—especially their distance, altitude and speed—could not be established. Investigators considered conventional explanations, including balloons, yet found the available evidence too incomplete to confirm one. The result is a case that remains unresolved not because it demonstrates extraordinary technology, but because the missing information prevents either confirmation or elimination of ordinary explanations.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

Four Objects illustration 1

What Did Two Airmen See South of Cheyenne?

The incident occurred around midnight on 22–23 May 1955, when Airman Basic I. J. Shapiro and E. C. Ingber of F.E. Warren Air Force Base were parked beside US Highway 85 approximately five miles south of Cheyenne. Weather conditions were reported to be clear enough for prolonged visual observation, allowing the men to watch the objects for about five minutes rather than only a few seconds.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

According to the surviving Project Blue Book summaries, the witnesses reported four distinct objects:

  • two appeared as slender vertical rectangles low on the horizon;
  • two others appeared higher in the sky as darker oval-shaped objects with what was described as dark blue illumination;
  • the objects remained visible long enough for the witnesses to compare their appearance rather than simply glimpse them in passing.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

The unusual combination of shapes is one reason the report has continued to attract attention. Unlike many sightings involving a single moving light, the witnesses distinguished between two different types of objects occupying different apparent positions in the sky.

The witnesses and the five-minute observation

One reason this case stands above many routine civilian reports is that both observers were serving airmen. Project Blue Book generally regarded trained military personnel as potentially more reliable observers because they were familiar with ordinary aircraft and military activity, although investigators did not assume their conclusions were necessarily correct.

The reported five-minute duration also mattered. Extremely brief sightings often leave little opportunity to judge shape or movement, whereas several minutes allow witnesses to compare objects and notice changes. Nevertheless, a longer observation does not automatically produce better evidence if the distance to the objects remains unknown. Without knowing whether the objects were hundreds of metres away or many kilometres distant, even experienced observers cannot accurately estimate their size or speed.

This limitation became central to the investigation. The witnesses could describe what they believed they saw, but they could not provide measurements that allowed investigators to reconstruct the event with confidence.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

Why balloons were considered but not confirmed

Project Blue Book explored whether balloons could account for the sighting. This was a routine part of investigations during the 1950s because weather balloons, research balloons and other lighter-than-air equipment were common, particularly around military installations.

A balloon hypothesis could potentially explain several features of the report:

  • apparently slow or stationary motion;
  • prolonged visibility;
  • unusual apparent shapes caused by lighting or viewing angle;
  • changing appearance as objects drifted at different altitudes.

However, investigators could not confirm that explanation. The surviving summaries indicate that the available evidence was insufficient to match the reported objects to known balloon launches or to demonstrate that the observed positions, numbers and appearance were consistent with a specific balloon flight. Rather than positively identifying balloons, investigators were left with a plausible possibility that could neither be proved nor ruled out.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

This distinction is important. The case was not officially resolved as “balloons”. Instead, balloons remained one of several ordinary explanations considered during the inquiry.

Four Objects illustration 2

What the missing distance and tracking data prevent us knowing

The greatest weakness in the case is not the witnesses’ credibility but the absence of objective measurements.

Investigators lacked several pieces of information that would have allowed a firmer conclusion:

  • Range: no reliable estimate of how far away the objects were.
  • Altitude: without distance, their height above the ground could not be calculated.
  • Speed: apparent motion across the sky cannot be converted into true speed without knowing range.
  • Independent tracking: there were no confirmed radar returns or additional observations that could establish the objects’ actual location.
  • Instrumental evidence: no photographs or physical traces accompanied the report.[NICAP]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

These missing data create multiple possible interpretations. Nearby balloons, distant aircraft, atmospheric effects or genuinely unusual aerial objects can all produce similar visual impressions when viewed against a night sky without reliable reference points.

1:11

'Project Blue Book' Ep. 1 Official Clip | UFO | SHOWTIME Documentary Series

Channel: SHOWTIME · Views: 290.8K · Uploaded: August 2021 · Length: 1 minute 11 seconds

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Why the case remained unresolved

The Cheyenne report illustrates how Project Blue Book’s “unidentified” category often reflected incomplete evidence rather than a judgement that something extraordinary had occurred.

Several factors worked in favour of the report’s credibility:

  • two independent military witnesses;
  • several minutes of observation;
  • an official Air Force investigation;
  • no immediately obvious conventional explanation that fitted every reported detail.

At the same time, significant weaknesses prevented a definitive conclusion:

  • uncertain observation geometry;
  • lack of precise timing and positional data;
  • no corroborating radar information;
  • no physical or photographic evidence;
  • no confirmed match with balloon operations or aircraft movements.[nicap.org]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

Because neither the witness testimony nor the available physical evidence decisively outweighed the competing explanations, the investigation ended without a firm identification.

Four Objects illustration 3

Why this sighting matters in Wyoming’s UFO history

Within the broader history of Cheyenne’s military skies, the May 1955 incident occupies an important middle ground. It is stronger than many anonymous civilian reports because identifiable military personnel reported the event through official channels. Yet it is far weaker than cases supported by radar, multiple independent witness groups or extensive documentary records.

For that reason, the sighting is best understood as an example of an honestly reported but ultimately indeterminate event. It demonstrates how even trained observers can encounter aerial phenomena that resist confident explanation when the most important observational data—distance, altitude and independent tracking—are missing. Rather than strengthening claims of extraordinary craft or conclusively supporting a mundane explanation, the surviving record leaves the case suspended between the two, making it one of the more noteworthy unresolved entries associated with Cheyenne in the Project Blue Book era.[nicap.org]nicap.org1955 ChronologyDecember 15, 2005…Published: December 15, 2005

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Endnotes

1. Source: nicap.org
Link:https://www.nicap.org/chronos/1955fullrep.htm

Source snippet

1955 ChronologyDecember 15, 2005...

Published: December 15, 2005

2. Source: nicap.org
Title: The Project Bluebook “Unknowns”
Link:https://www.nicap.org/bluebook/unknowns.htm

Source snippet

The Project Bluebook "Unknowns"...

3. Source: nicap.org
Title: UF O Report
Link:https://www.nicap.org/reports/550518niagarafalls_report.htm

Source snippet

UFO ReportOctober 24, 2011 — Image From: daniel wilson <daniejon2000@yahoo.co.uk> Date: Mon, Oct 24, 2011 at 8:03 AM Subject: May 18, 195...

Published: October 24, 2011

4. Source: nicap.org
Title: section_11But they were seen within a very few minutes of each other
Link:https://www.nicap.org/ufoe/section_11.htm

5. Source: nicap.org
Link:https://www.nicap.org/bluebook/bluelist.htm

6. Source: nicap.org
Link:https://www.nicap.org/bluebook/PBBSR14.htm

7. Source: nicap.org
Title: Challenge of UFOs
Link:https://www.nicap.org/books/coufo/coufo_complete.htm

8. Source: time.com
Title: science saucer blue book
Link:https://time.com/archive/6610271/science-saucer-blue-book/

9. Source: nicap.org
Title: UF O Report
Link:https://www.nicap.org/550504keflavik_dir.htm

10. Source: ufologie.patrickgross.org
Link:https://ufologie.patrickgross.org/htm/bluebooku55.htm

Source snippet

UFOs at close sight: Project Blue Book unexplained cases summaries with witnesses names, 1955...

11. Source: archives.gov
Title: Project BLUE BOOK
Link:https://www.archives.gov/research/military/air-force/ufos

Source snippet

Unidentified Flying Objects | National ArchivesJune 25, 2024 — PROJECT BLUE BOOK - UNIDENTIFIED FLYING OBJECTS GENERAL INFORMATION The Un...

Published: June 25, 2024

12. Source: bibliotecapleyades.net
Title: Project Blue Book
Link:https://www.bibliotecapleyades.net/Sociopolitica/esp_sociopol_mj12_12d.htm

Additional References

13. Source: ufoinsight.com
Link:https://www.ufoinsight.com/ufos/sightings/first-active-years-bluebook

Source snippet

The First Active Years: Unsolved Case Files Of Project Blue Book - UFO InsightNovember 28, 2021 — As he was driving down Highway 395, he...

Published: November 28, 2021

14. Source: theblackvault.com
Title: Project Blue Book Unknown Case Files, Complete List
Link:https://www.theblackvault.com/casefiles/project-blue-book-unknown-case-files-complete-list/

Source snippet

12:38 p.m. Witnesses: Lt. Col. E.J. Stealy, lst Lt. J.W. Burt. About 10 round, white objects, one of which left a brief smoke trail, flew...

15. Source: theblackvault.com
Title: 14 was a massive statistic
Link:https://www.theblackvault.com/documentarchive/project-blue-book-special-report-14-may-5-1955/

Source snippet

Project Blue Book Special Report #14 – May 5, 1955 - The Black VaultSeptember 17, 2020 — PROJECT BLUE BOOK SPECIAL REPORT #14 – MAY 5, 19...

Published: May 5, 1955

16. Source: disclosurevault.org
Title: The Disclosure Vault
Link:https://www.disclosurevault.org/docs/3022454e-4008-455d-a288-d4259ab8d41c

Source snippet

June 12, 2026 — T1 · RELEASE · CIA - UAP Records (June 2026) CIA-D015: PROJECT BLUE BOOK SPECIAL REPORT NO 14 The Air Technical Intellige...

Published: June 12, 2026

17. Source: youtube.com
Title: The True Story Behind US Government Investigations Into UFOs | Project Blue Book
Link:https://www.youtube.com/watch?v=qdTVsr4O4HA

Source snippet

Project Blue Book: America's Obsession with UFOs...

18. Source: youtube.com
Link:https://www.youtube.com/watch?v=NXgx9QDKSD4

Source snippet

The True Story Behind US Government Investigations Into UFOs | Project Blue Book...

19. Source: youtube.com
Link:https://www.youtube.com/watch?v=1cO5K1np2Ig

Source snippet

'Project Blue Book' Ep. 1 Official Clip | UFO | SHOWTIME Documentary Series...

20. Source: si.edu
Link:https://www.si.edu/object/siris_sil_259088

21. Source: af.mil
Link:https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104590/unidentified-flying-objects-and-air-force-project-blue-book/

22. Source: youtube.com
Title: Project Blue Book: America’s Obsession with UFOs
Link:https://www.youtube.com/watch?v=Xu4oTBBI5UE

Source snippet

Project Blue Book Exposed (2020) [Documentary]...