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What Is the Philadelphia Experiment? The Case of the Vanishing Ship

Emilie Peck is a freelance writer. She is also a student of alternative medicine, including massage therapy, herbalism and aromatherapy.

In some circles, the USS Eldridge is known for a mysterious disappearance at the hands of Naval scientists during the Philadelphia Experiment.

In some circles, the USS Eldridge is known for a mysterious disappearance at the hands of Naval scientists during the Philadelphia Experiment.

Only magicians can make large things like tanks, elephants, and sometimes large buildings disappear with impressive sleight of hands. Why not a warship? Some believe the U.S. Navy actually succeeded in rendering one invisible and transporting it instantaneously. This was core to the Philadelphia Experiment—but there was much more to the story.

The Philadelphia Experiment Comes to Light

The story was first told to Morris K. Jessup, author of The Case for the UFO. On January 13, 1956, he received a letter from someone calling themselves Carlos Allende claiming to have knowledge about a top-secret government experiment. Accompanying the letter were two newspaper articles which weren’t sourced very well.

The story intrigued him, so he replied with a request for more information. The letter he received in return did not inspire confidence. The sender had changed his name to Carl M. Allen and stated that he had no more information. He mentioned hypnosis as a way to encourage more memories. The combination of the change in names and claim of ignorance turned Jessup off to the potential to lead to an interesting story, and he halted correspondence. Little did he know, this unpromising source wasn’t done with him.

Early the following year, he received a request from the Office of Naval Research to give them some insight into a shipment they’d received. The ONR was the naval equivalent to the Air Force’s Project Blue Book, and they had received a copy of Jessup’s book in a package labeled simply, “Happy Easter."

The book’s margins were full of notes in three different colors of ink and three different styles of handwriting. Whoever had made those notes appeared to have a profound knowledge of the UFO phenomenon and government procedures. Odder still, the three individuals referred to each other as if they were all part of an alien race.

Upon closer examination, Jessup was able to identify one set of handwriting as belonging to Allen.

Between the book, the original letters, and subsequent correspondences, the strange tale of the USS Eldridge, a destroyer escort, came to light. Allen has to have been witness to some incredible events while he worked at the Philadelphia Naval Shipyard in 1943.

In July, he witnessed the first attempt by the Naval to turn a ship invisible. The July experiment only succeeded in turning parts of the ship invisible. Things were business as usual for the rest of the summer, and well into the fall.

On October 28, Allen noticed a strange green mist surrounding the Eldridge. What followed was first an extremely strange sequence of visual effects, before the ship vanished completely. Within seconds, it appeared again over 200 miles away, in Norfolk, Virginia. However, it reappeared in Pennsylvania in under a minute.

Possible Theories

It had been crewed by the minimal amount of men possible, and those who were unfortunate enough to be on the ship at the time suffered terrible side effects from the unexpected ride. Many were partially fused with the ship, and at least two were completely buried in the steel of the deck. Those who escaped physically unharmed apparently went mad, and most of them were institutionalized.

One memorable story came from a nearby bar. The place was a popular watering hole for the Yard workers, and as happens when a little too much alcohol flowed a little too freely, a bar brawl broke out. This fight would have been just like all of the others if the combatants hadn’t been vanishing and reappearing throughout it.

This had all been the result of a naval experiment to camouflage warships from the enemy through invisibility, but the transportation and injury done to the crew were unintended. Allen explained that it was based on Einstein’s Unified Field Theory, which stated in part that when the light is bent, space-time is as well. The scientists took the theory another step, and used the idea that electromagnetism and gravity were in the same field as light and space-time as a way to achieve true invisibility. The greenish fog Allen had seen apparently had something to do with high electromagnetic fields, which were also responsible for the injury done to the men.

It's thought that the official name for the Philadelphia Experiment was Project Rainbow. The Navy doesn't have record of a project of that name, but the Air Force did. The Air Force's Project Rainbow's goal was to create a way for their Lockheed U-2 fighters difficult or impossible for the Soviets to track via radar.

"Rainbow" was also in use over the course of WWII as code for the nations of the Axis powers.

George Gosse, a specialist with the Australian Navy diffuses a magnetic German mine.

George Gosse, a specialist with the Australian Navy diffuses a magnetic German mine.

Jessup’s Mysterious Demise and Carl Allen’s Inconsistencies

Eventually, Jessup was hooked on the story, and he moved forward with his investigation. By then, the Navy duplicated the annotated book and distributed it to about 100 people in their employ. You can still find copies online under the title of the “Varo Edition."

Although Jessup continued to research the case and write about it, he found no luck in publishing his work again. Eventually, his wife left him, his emotional state deteriorated, and his career suffered because of it.

Still, he continued with his research, and in April of 1959, he made a breakthrough. Excited, he got in touch with his friend, Dr. Manson Valentine, who also had an interest in the case, and scheduled a dinner to discuss his findings. Strangely, before they could meet up, Jessup’s car was found with the engine on and a hose running from the tailpipe into the cab of the car. Jessup was inside, and he died of carbon monoxide poisoning before help could arrive.

According to his daughter, the author had been struggling with depression, so suicide isn’t out of the question. However, it’s strange that he would choose to take his own life so soon after making such a promising breakthrough. We’ll probably never know what he discovered.

Although one of the main driving forces behind this mystery had died, interest lived on. Allen continued writing letters and sending them from various locations. Eventually, the Philadelphia Experiment inspired a number of books and movies.

Frustrated with the fact that everyone but him seemed to be making money off of his story, Allen eventually stepped forward to expose the whole thing as a hoax. Still, later, he publicly admitted that the project was not a hoax, and that he’d been truthful in his writings.

The Official Explanation

Even without Allen’s admission, the Philadelphia Experiment is viewed as being a combination of false memory, a misidentified phenomenon, and a hoax.

The Navy had been working on a project to render its fleet invisible to German magnetic mines through a process of degaussing. This process dramatically reduced or completely eliminated a ship’s magnetic field through the use of electromagnetic coils. One of the side effects of these powerful electromagnetic forces is what’s called a corona discharge. That is simply a glow around the electric conductors used during the process. Although any watches not collected before the coils charged stopped working, no one taking part in the experiments was harmed.

The biggest detriment to the Philadelphia Experiment is the fact that the USS Eldridge has never been in the Philadelphia Navy Yard. It was commissioned in the New York Navy Yard, and stayed there from August 27, 1943, to September 16, 1943. From there, it went to Bermuda, where it went through exercises until October 15th of that same year. Naval logs can trace its history up to the point where it joined the Greek fleet as the warship Leon. It remained in service there from 1955 through 1992. In 1999, it was dismantled and sold as scrap metal.

Eventually, Carlos Allende’s true identity was revealed. Born Carl Meredith Allen, he tested at a genius IQ level. However, he performed poorly in school and wasn’t inclined to take part in public relations very often. Allen’s favored occupation was to read books and other publications, add his notes to the margins and send them off to parties who he thought would be interested. Once he found out about the ONR, he apparently thought they’d benefit from his copy of The Case for the UFO.

Corona discharges on a high energy power line.

Corona discharges on a high energy power line.

Even though the Philadelphia Experiment is believed to have been thoroughly discredited by the majority of people, many still believe that it had actually happened. They say naval records had been altered after the fact, and survivors were forced to maintain silence about the matter.

Whether it happened or not, it’s still a fascinating story and will continue to prompt fictional pieces for years to come.


Emilie S Peck (author) from Minneapolis, MN on July 27, 2013:

Thank you! I'm glad you liked it.

Michele Travis from U.S.A. Ohio on July 26, 2013:

Very interesting hub. Thank you for sharing it!