Project Interloper
Project Interloper was a joint US Air Force–US Navy investigation into both aerial and underwater UAP, initiated in 1951 by USAF Major Dewey Fett, a sitting member of Project Blue Book. Interloper is the earliest known US government program specifically targeting Unidentified Submerged Objects and represents a deliberate effort to investigate maritime UAP outside the publicly accountable structure of the official Air Force investigation.
| Span | 1951 – 1953 |
|---|
Structure and Classification
Interloper was structured as an extra-governmental investigation — deliberately placed outside the normal chain of command and explicitly exempt from Freedom of Information Act requests. This was a notable organizational choice: Fett was simultaneously a Blue Book member, yet chose or was directed to conduct Interloper using a classification framework that would prevent future public disclosure through standard FOIA mechanisms. UAP Gerb speculates this structure was either directed by senior US government elements or was chosen to shield maritime UAP intelligence from congressional or public scrutiny.
CIA Briefing and Suppression
In 1953, Project Interloper briefed the CIA on its findings — establishing a pattern of routing sensitive UAP intelligence to the intelligence community while bypassing Congress and the public. Despite this briefing, Interloper's findings never reached elected officials or the American people, and the project's formal conclusions remain unknown.
Surviving Case Files
Only three case files from Project Interloper are known to survive: cases 26, 27, and 28. Of these, Case 26 is directly relevant to USO research:
Case 26 — Documents Lieutenant George P. Williams and his nine-man US Navy Fleet Logistics Air Wing crew observing a trans-medium UFO emerge from the ocean between Keflavik, Iceland, and Newfoundland. The object initially resembled a ship before rising from beneath the cloud deck and approaching the Navy aircraft at what the crew described as a "terrifying closing rate." It hovered near the aircraft's port side before accelerating away. The object was elliptical or cigar-shaped, estimated at a minimum of 200 feet in length, with a red-orange glow along its periphery.
Cases 27 and 28 are not maritime USO cases and fall outside the primary scope of UAP Gerb's USO investigation.
Legacy
The existence of Project Interloper — discovered decades after its operation — suggests that the US government recognized the USO phenomenon as early as 1951 and deliberately created investigative infrastructure for it outside any publicly accountable process. The project's FOIA exemption, its CIA-only briefing structure, and the near-total loss of its case files are consistent with the broader pattern of maritime UAP data being more heavily classified than aerial UAP data.
The Office of Naval Intelligence (ONI) was involved in compiling associated reports, including the nine submarine contact reports submitted via AFOIN-X-SG in April 1952.