This Is the Truth Behind WWII’s Creepy Philadelphia Experiment

As military urban legends go, the Philadelphia Experiment is one of the creepiest and most grotesque ever. It alleges that there was a secret U.S. Navy experiment on the USS Eldridge during World War II and claims the ship was made invisible or "cloaked" to radar and even teleported or time-traveled. 

Originating from claims by Carl M. Allen and Morris K. Jessup in the 1950s, proposed explanations include mistaken identity, misinterpretation of real experiments, and fabrication for entertainment. 

It has endured as an infamous WWII conspiracy theory. But is there any truth to it? Let's take a look.

According to legend, on Oct. 28, 1943, the USS Eldridge, a Cannon-class destroyer escort, was conducting top-secret experiments designed to win command of the oceans against the Axis powers. The rumor was that the government was creating technology that would render naval ships invisible to enemy radar, and there in the Philadelphia Naval Shipyard, it was time to test it out.

Witnesses claim an eerie green-blue glow surrounded the hull of the ship as her generators spun up and then, suddenly, the Eldridge disappeared. The ship was then seen in Norfolk Naval Shipyard in Virginia before disappearing again and reappearing back in Philadelphia.

The legend states that classified military documents reported that the Eldridge crew were affected by the events in disturbing ways. Some went insane. Others developed mysterious illness. But others still were said to have been fused together with the ship; still alive, but with limbs sealed to the metal.

That'll give you nightmares. That's some “Event Horizon” sh*t right there.

Which is actually a convincing reason why the Eldridge's story gained so much momentum.

In a 1994 article for the Journal of Scientific Exploration, Jacques F. Vallee theorized that deep-seated imagery is key to planting a hoax into the minds of the masses and of the educated public.

But before we break down what really happened that day, let's talk about the man behind the myth: Carl M. Allen, who went by the pseudonym Carlos Miguel Allende. In 1956, Allende sent a series of letters to Morris K. Jessup, author of the book “The Case for the UFO,” in which he argued that unidentified flying objects merit further study.

Jessup apparently included text about unified field theory because this is what Allende latched onto for his correspondences. In the 1950s, unified field theory, which has never been proven, attempted to merge Albert Einstein's general theory of relativity with electromagnetism. In fact, Allende claimed to have been taught by Einstein himself and could prove the unified field theory based on events he witnessed on Oct. 28, 1943.

Allende claimed that he saw the Eldridge disappear from the Philadelphia Naval Yard, and he further insisted that the United States military had conducted what he called the Philadelphia Experiment — and was trying to cover it up.

Jessup was then contacted by the Navy's Office of Naval Research, which had received a package containing Jessup's book with annotations claiming that extraterrestrial technology allowed the U.S. government to make breakthroughs in unified field theory.

This is one of the weirdest details. The annotations were designed to look like they were written by three different authors -- one maybe extraterrestrial? According to Vallee's article for the Journal of Scientific Exploration, Jessup became obsessed with Allende's revelations, and the disturbed researcher took his own life in 1959. It wasn't until 1980 that proof of Allende's forgery was made available.

Inexplicably, two ONR officers had 127 copies of the annotated text printed and privately distributed by the military contractor Varo Manufacturing, giving wings to Allende's story long after Jessup's death.

So what really happened aboard the USS Eldridge that day?

According to Edward Dudgeon, who served in the U.S. Navy aboard the USS Engstrom, which was dry-docked in the Philadelphia Naval Yard while the Eldridge was, both ships did have classified devices on board. They were neither invisibility cloaks nor teleportation drives designed by aliens, but instead, they scrambled the magnetic signatures of ships using the degaussing technique, which provided protection from magnetic torpedoes aboard U-boats.

How Stuff Works suggested that the "green glow" reported by witnesses that day could be explained by an electric storm or St. Elmo's Fire, which, in addition to being an American coming-of-age film starring the Brat Pack, is a weather phenomenon in which plasma is created in a strong electric field, giving off a bright glow, almost like fire.

Finally, inland canals connected Norfolk to Philadelphia, allowing a ship to travel between the two in a few hours.

The USS Eldridge was transferred to Greece in 1951 and sold for scrap during the 1990s, but Allende's hoax would live on in our effing nightmares forever.

More articles from We Are the Mighty: 

• 6 urban legends about Wright-Patterson Air Force Base
• Why Okinawa is the most haunted place in the military
• 11 scary ghost stories, legends, and haunted military bases

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