The Philadelphia Experiment, also known as Project Rainbow, is one of the most talked about military urban legends of all time.
To this day, it continues to divide opinion over what is fact and what is fiction and has even been immortalised in a Hollywood film.
The government experiment is said to have taken place on October 28, 1943 and apparently saw the USS Eldridge, a Cannon-class destroyer escort, disappear.
It is claimed that the event was witnessed by an ex-merchant mariner named Carl M. Allen, who was on a nearby ship, Liberty.
The ship is also said to have matter-transported from one naval yard to another.
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The Philadelphia Experiment was classified by the government as a level beyond Top Secret.
According to conspiracy theorists, Albert Einstein, who worked for the US Navy during World War II, was drafted in to combat the losses of ships to German U-Boat submarines.
The navy then reportedly used a version of Einstein’s Unified Field Theory to bend light and leave the ship invisible, as it was encased in an electro-magnetic fog.
The intention was to make sure they couldn't be detected by the enemy.
Robert Goerman, author and researcher, said: “He [Carl M. Allen] says he saw the ship enveloped in a green fiery fog.
“He says he could insert his arm into the terrific flow of this energy then the ship disappeared.”
The ship then apparently momentarily teleported to a naval dockyard in Norfolk, Virginia before reappearing in Philadelphia.
If legend is to be believed, the experiment had horrific consequences, with sailors becoming molecularly fused to the vessel.
As the ship teleported, men were driven insane, with some even catching fire.
Alfred Bielek, author of The Philadelphia Experiment and other Conspiracies, said: “The first thing they found was two sailors buried in the steel deck, dying or near dead.”
Other sailors were reported as missing or developed strange illnesses.
The Navy is then said to have shelved the experiment, forcing all of those involved to sign an oath of secrecy.
Not everyone believes the legend and sceptics say the occurrences can be easily explained.
The reported green glow seen around the ship could have been what is known as St Elmo’s Fire.
This weather phenomenon happens when plasma creates a strong energetic field, giving off a bright glow.
In regards to teleportation claims, inland canals connected Norfolk to Philadelphia during the time of the experiment.
These canals allowed ships to travel between the two places in just a few hours.
The Navy also did conduct experiments to make vessels "invisible", however, they just used this word to describe the technology created to help ships sail undetected by the enemy.
Germany was using magnetic limpet mines which were capable of attaching themselves to the metal hull of ships as they came near.
The technology tested in Philadelphia would make the ships "invisible" to the magnetic properties of the mines.
