PURSUE archive · catalogue card
DOW-UAP-D154
Transcript of a Presentation by Captain Edward J. Ruppelt, 1952
This card reproduces what the official catalogue publishes. Our own analysis (cross-checked sources, timeline and hypotheses) will come when its turn arrives in the weekly review.
- Agency
- Department of War
- Incident date
- Mar 26, 1952As the catalogue writes it: “3/26/52”
- Place
- Boston, MassachusettsAs the catalogue writes it: “Boston, Massachusetts”See the area on the globe →
- Published in PURSUE
- Sep 18, 2026
- Records
- 2 records · Document + Audio
01 Official description
This document is a transcript of a March 1952 presentation by Captain Edward J. Ruppelt outlining the U.S. Air Force’s reorganized investigation into unidentified flying objects (UFOs). The presentation previews prospective technical methodologies, such as diffraction-grating photography and radar-scope synchronization, that were subsequently incorporated into Project Blue Book, a U.S. Air Force program active from 1952 to 1969 that investigated the nature and origin of UFOs. Ruppelt explains that out of approximately 800 historical cases reviewed by the Air Force, approximately 20% remained unexplained after technical analysis. These unresolved reports were sourced from credible military personnel, commercial pilots, and other qualified technical observers. He highlights geographic report concentrations around sensitive national security and nuclear weapons installations (including Los Alamos, Albuquerque, and Oak Ridge National Laboratories) and notes recurring anomalous characteristics, including silent high-speed flight and radar detections indicating unconfirmed air speeds between 1,000 and 3,500 miles per hour. Emphasizing that the Air Force found no conclusive evidence regarding the nature or origin of the phenomena, Ruppelt underscores the national security need for a systematic physical data collection effort to better evaluate these sightings.
02 Catalogue records · 2
DOW-UAP-D154 · Document · Department of War · Sep 18, 2026 · Main record
Transcript of a Presentation by Captain Edward J. Ruppelt, 1952
3/26/52 · Boston, Massachusetts
DOW-UAP-PR160 · Audio · Department of War · Sep 18, 2026
Presentation by Captain Edward J. Ruppelt, 1952
3/26/52 · Boston, Massachusetts
DVIDS · broken link in the catalogue (checked Oct 5, 2026)
Official description
This audio file records a March 1952 presentation by Captain Edward J. Ruppelt, outlining the U.S. Air Force’s reorganized investigation into unidentified flying objects (UFOs). The presentation previews prospective technical methodologies, such as diffraction-grating photography and radar-scope synchronization, that were subsequently incorporated into Project Blue Book, a U.S. Air Force program active from 1952 to 1969 that investigated the nature and origin of UFOs. Ruppelt explains that out of approximately 800 historical cases reviewed by the Air Force, approximately 20% remained unexplained after technical analysis. These unresolved reports were sourced from credible military personnel, commercial pilots, and other qualified technical observers. He highlights geographic report concentrations around sensitive national security and nuclear weapons installations (including Los Alamos, Albuquerque, and Oak Ridge National Laboratories) and notes recurring anomalous characteristics, including silent high-speed flight and radar detections indicating unconfirmed air speeds between 1,000 and 3,500 miles per hour. Emphasizing that the Air Force found no conclusive evidence regarding the nature or origin of the phenomena, Ruppelt underscores the national security need for a systematic physical data collection effort to better evaluate these sightings.
03 Related cases
Other catalogue cards from the same area or the same decade.
04 Sources
- [1]
Record · U.S. Department of War
Presidential Unsealing and Reporting System for UAP Encounters (PURSUE)
Card, descriptions and comments: PURSUE catalogue, U.S. Department of War. The files are not hosted here; they open on their official site.
Checked on Oct 4, 2026 · Open the original ↗
May contain errors by the AI and the editor · always check the official source.