The Philadelphia Experiment is an alleged military experiment supposed to have been carried out by the U.S. Navy at the Philadelphia Naval Shipyard in Philadelphia, Pennsylvania, sometime around October 28, 1943. The U.S. Navy destroyer escort USS Eldridge was claimed to have been rendered invisible (or “cloaked”) to enemy devices.
The story first appeared in 1955, in letters of unknown origin sent to a writer and astronomer, Morris K. Jessup. It is widely understood to be a hoax; the U.S. Navy maintains that no such experiment was ever conducted, that the details of the story contradict well-established facts about USS Eldridge, and that the alleged claims do not conform to known physical laws.
What actually happened in the Philadelphia Experiment has been highly exaggerated, although it is still very interesting. Following is a quotation of a section of an article in the “Journal of Scientific Exploration“, Volume 8, Number 1, Spring, 1994. Copyright 1994 Society for Scientific Exploration. “Articles may be photocopied for noncommercial usage such as research, teaching, distribution as classroom material, etc.” Address: ERL 306, Stanford University, Stanford, CA 94305-4055. The article is entitled “Anatomy of a Hoax: The Philadelphia Experiment 50 Years Later”, by Jacques F. Vallee:
What Actually Happened in Philadelphia
In an earlier assessment of the Philadelphia Experiment data, the author offered the tentative conclusion that the story was, in part, based on fact: the Navy may have been involved in technically-advanced, classified tests in the Fall of 1943 (Vallee, 1991). These developments could have been misunderstood or deliberately romanticized by people like Allende, just as today we find tests of advanced flying platforms at Nellis Air Force Base being misinterpreted by believers. Furthermore I hypothesized that the experiments had to do with a radar countermeasures test. Indeed a Raytheon advertisement published thirteen years ago suggested that the corresponding technology was now out in the open (Raytheon, 1980). This hypothesis, however, failed to explain a few of the facts that highlighted the story. In particular it did not account for the observed disappearance of the destroyer from the harbor, for the mysterious devices brought on board under extreme security precautions, or for the alleged disappearance of two sailors from a nearby tavern. I called out to any one of my readers who might have additional information. That is how I came to correspond, and later to meet face to face, with Mr. Edward Dudgeon.
“I am a sixty-seven year old retired executive. I was in the Navy from 1942 through 1945,” began Mr. Dudgeon’s letter (Dudgeon, 1992) explaining his purpose in contacting me. He confirmed that the idea of an actual, secret technical development was correct, but he said I was wrong about a radar test. The truth, as he patiently wrote to me, was simpler.
I was on a destroyer that was there at the same time as the Eldridge DE 173…. I can explain all of the strange happenings as we had the same secret equipment on our ship. We were also with two other DEs and the Eldridge on shakedown in Bermuda and return to Philadelphia.
My correspondent suggested a meeting, adding “I am not looking for any compensation for this or media exposure. I just want someone to know what I know before it is too late.”
A few weeks later I met with Mr. Dudgeon, who produced his identification and his discharge papers from the U.S. Navy. Over the next two hours he gave me the details of his story and answered my questions.
“You must realize that in forty three, the Germans had been sinking our ships as fast as they came out of the harbors into the Atlantic, which they called “the Graveyard.” I was just a kid then. In fact I falsified my birth certificate in order to join the Navy in 1942. I was only sixteen at the time, turning seventeen in December of 1942.”
“What was your training?” I asked him.
“I studied electronics at Iowa State. The Navy sent me to electronics school after boot camp. I graduated with the title of “electrician’s mate third class” in February of 43, and then I went aboard ship in June 1943.”
“Can you give me the name of the vessel?”
“Oh yes, the DE 50, U.S.S. Engstrom. It was a diesel electric ship, as opposed to the DE 173, the Eldridge, which was steam electric. These ships were run by the electricians. Our ship was put in dry dock so they could install high-torque screws.”
“Why the special equipment?”
“The new screws made a sound of a different pitch, which made it harder for the submarines to hear us. They also installed a new sonar for underwater detection, and a device we called a “hedgehog” which was mounted in front of the forward gun mount on the bow. It fired depth charges in banks of twenty-four to thirty in a pattern, and could cover 180 degrees as far as about a mile away. That was one of the secrets. Your book Revelations was wrong about making the ship invisible to radar: the Germans hadn’t deployed radar at the time. We were trying to make our ships invisible to magnetic torpedoes, by de-Gaussing them. We had regular radar and also a “micro-radar” of lower frequency. They could detect submarines as soon as they raised their periscopes or came up for air. We could pick them up in the dark or in fog as far as one or two miles away. That’s when the Germans began to lose their U-boats.”
“How does this relate to the Eldridge?” I asked Mr. Dudgeon.
“The Eldridge and the Engstrom were in the harbor together,” he answered. “In fact four ships were outfitted at the same time: the 48, 49, 50 and the Eldridge, in June and July of 1943. The Navy used to de-Gauss all the ships in dry dock, even the merchant ships, otherwise the vessels acted as bar magnets which attracted the magnetic torpedoes.”
“What was the procedure for shakedown?”
“All four ships went to Bermuda, which as a relay for the convoys to North Africa. There were several other destroyers there. They would send us out to train us to convoy. We also had a base in the Azores. The destroyers would go halfway and return to their respective base. The shakedown was scheduled for up to eight weeks but we only took five weeks to become proficient. We were there from the first week of July to the first week of August.”
“What was your exact assignment on board?”
“I was electrican’s mate third class petty officer. Our job was to make the ship speed up, slow down or reverse according to the bridge signals. Eight months later I was promoted to to second class. Eventually we were sent to the Pacific. I served on that ship for a year and a half, from June 1943 to November 1944. Then I was sent to a special school at Camp Perry, Virginia.”
“Whatever happened to the Eldridge?”
“We separated with her after the shakedown. The DE 48 and the Eldridge stayed in the Atlantic, based in Bermuda until early 1944, then they went to the Pacific theater too. The DE 49, which was our sister ship, and the DE 50 headed through Panama mid-September 1943 and were in the Pacific theater thereafter. Ther was nothing unusual about the Eldridge. When we went ashore we met with her crew members in 1944, we had parties, there was never any mention of anything unusual. Allende made up the whole thing.”
“What about the luminous phenomena he described?”
“Those are typical of electric storms, which are very spectacular. St. Elmo’s fire is quite common at sea. I remember coming back from Bermuda with a convoy and all the ships being engulfed in what looked like green fire. When it started to rain the green fire would disappear.”
“Did you hear of Einstein being involved with Navy experiments at the time?”
“No. I believe that Einstein worked with the radar development group, but he wasn’t involved in running actual tests. At least I never heard of it.”
“How were the classified devices actually installed?”
“After the Navy commissioned the ship and we were ready to go to sea, the National Bureau of Standards brought a master compass in a box that looked like a foot locker and we made several runs a sea in different directions to calibrate the ship’s compass against the master. That’s the mysterious “box” that various reports have mentioned.
“Who was Allende? Did you ever meet him?” I asked, showing Mr. Dudgeon the various letters I had received from the man.
“I never did meet him. From his writings I don’t think he was in the Navy. But he could well have been in Philadelphia at the time, serving in the merchant marine. He could also have been aboard a merchant ship we escorted back to the Philly-Norfolk area during a storm.”
“What about the claim that generators were placed into the hold?”
“Aboard all diesel-electric and steam-electric destroyers there were two motors that turned a port or starboard screw. Each motor was run by a generator.”
“What was the procedure when the Navy de-Gaussed a ship?”
“They sent the crew ashore and they wrapped the vessel in big cables, then they sent high voltages through these cables to scramble the ship’s magnetic signature. This operation involved contract workers, and of course there were also merchant ships around, so civilian sailors could well have heard Navy personnel saying something like,”they’re going to make us invisible,” meaning undetectable by magnetic torpedoes, without actually saying it.”
“What about the smell of ozone?”
“That’s not unusual. When they were de-Gaussing you could smell the ozone that was created. You could smell it very strongly.”
“What security precautions were taken?”
“Our skipper warned us not to talk about the radar, the new sonar, the hedgehog, and the special screws. But you know how it is, information will always leak out. Another classified device we had was the “foxer,” which we immersed in the sea off the fantail and dragged half a mile to a mile behind the destroyer. It gave off signals resembling the sound of a merchant vessel’s screw. This attracted the German subs which fired acoustic-seeking torpedoes at it, giving away their position and wasting ammunition.”
“How long had all this secret equipment been available?”
“About six to eight months, as far as I can tell. By the time we sailed out, submarine warfare had turned in our favor along the East Coast.”
“This doesn’t tell us how the Eldridge disappeared into thin air, or what actually happened in the tavern in early August 1943.”
“That’s the simplest part of the whole story,” Mr. Dudgeon replied. “I was in that bar that evening, we had two or three beers, and I was one of the two sailors who are said to have disappeared mysteriously. The other fellow was named Dave. I don’t remember his last name, but he served on the DE 49. The fight started when some of the sailors bragged about the secret equipment and were told to keep their mouths shut. Two of us were minors. I told you I cheated on my enlistment papers. The waitresses scooted us out the back door as soon as trouble began and later denied knowing anything about us. We were leaving at two in the morning. The Eldridge had already left at 11 p.m. Someone looking at the harbor that night must have noticed that the Eldridge wasn’t there any more and it did appear in Norfolk. It was back in Philadelphia harbor the next morning, which seems like an impossible feat: if you look at the map you’ll see that merchant ships would have taken two days to make the trip. They would have required pilots to go around the submarine nets, the mines and so on at the harbor entrances to the Atlantic. But the Navy used a special inland channel, the Chesapeake-Delaware Canal, that bypassed all that. We made the trip in about six hours.”
“Why did the ships have to go to Norfolk?”
“Norfolk is where we loaded the explosives. Those docks you see on the aerial photographs are designed for ammunition. The Navy loaded ships twenty-four hours a day. They could load a destroyer in four hours or less. I know that’s where the Eldridge went, and she wasn’t invisible, because we passed her as she was on the way back from Virginia, in Chesapeake Bay.”
“In other words, the process was: out of dry dock, down the canal, loading ammunition in Norfolk, back to Philadelphia, out to sea to set the compasses and test radar and sonar gear?”
“Exactly. The Eldridge never disappeared. All four ships went to Bermuda in July 43 and came back together in early August. During that time we were also caught in a storm that created a display of green fire accompanied by a smell of ozone. The glow abated when it started raining.”