Philadelphia Experiment

The Legend

The Philadelphia Experiment is one of UFO folklore's most persistent urban legends. The claim alleges that on or around October 28, 1943, the U.S. Navy conducted a secret experiment at the Philadelphia Naval Shipyard to render the destroyer escort USS Eldridge invisible and teleport it from Philadelphia to Norfolk, Virginia. According to the legend, the ship then vanished from Norfolk and reappeared in Philadelphia.

Origins: The Allende Letters

The story originated with Carl Meredith Allen, also known by the alias Carlos Miguel Allende. Beginning in January 1956, Allen sent over 50 handwritten letters to UFO researcher Morris K. Jessup, claiming to have witnessed the experiment while serving aboard the merchant ship SS Andrew Furuseth in Philadelphia Harbor.

In his letters, Allen cited unpublished theories by Albert Einstein and referenced a scientist named Franklin Reno conducting the experiment using unified field theory. He would later revise his account to invoke degaussing—an actual Navy process for neutralizing a ship's magnetic signature against German magnetic mines—though degaussing involves electromagnetic deactivation, not physical invisibility.

Allen also annotated a copy of Jessup's book The Case for the UFO with three-color handwritten commentary, appearing to document debates about extraterrestrial propulsion. These papers are archived at the University of Wyoming's American Heritage Center.

Popularization and Debunking

The legend gained mainstream attention with the 1979 book The Philadelphia Experiment: Project Invisibility by Charles Berlitz and William L. Moore. However, the book was widely criticized for plagiarizing narrative elements from the 1978 science fiction novel Thin Air, and for making unsupported claims that Einstein had completed and destroyed theoretical work.

Comprehensive debunking came swiftly:

• USS Eldridge logs: The ship's deck log and war diary (preserved on microfilm) show the vessel was never in Philadelphia between August and December 1943. A 1999 reunion of USS Eldridge veterans confirmed the ship never made port in Philadelphia.

• Navy statement: The Office of Naval Research officially stated in 1996 that it had never conducted radar invisibility research and was not even established until 1946—making a 1943 experiment impossible under its mandate.

• No documentation: Despite decades of searching by Navy staff and independent researchers, no official records have been found to support the claim of any invisibility or teleportation experiment.

Cultural Impact

Despite its debunked status, the Philadelphia Experiment remains one of UFO culture's most iconic legends. It has inspired novels, films, and documentaries, serving as a touchstone for government secrecy narratives and theoretical physics speculation. The legend exemplifies how a hoax can achieve cultural permanence through retelling, even after authoritative refutation.