The Philadelphia Experiment
RefutedRuled out by official inquiry or direct observation
The claim
The US Navy was said to have made a warship invisible in an experiment in 1943.
Where it started
The story began with letters sent by one man to an astronomy writer in the 1950s, and spread widely through a 1979 book and a 1984 film.
Where it stands
The Navy states that no such experiment took place and that the deck logs of the ship named in the story place it elsewhere at the time. What did happen was degaussing work to protect ships against magnetic mines, and that appears to be the origin of the idea of making a ship disappear.
Primary sources
- 미 해군 역사유산사령부history.navy.milOfficial source
checked 2026-09-07
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