An amazing family story by ENS Ray Kethledge, USN.  ENS Kethledge is currently attending the Cryptologic Warfare Officer Basic Course (CWOBC) at Corry Station Pensacola.

During the early years of World War II, my great-grandfather, Raymond W. Ketchledge, earned his bachelor’s and master’s degrees in electrical engineering from the Massachusetts Institute of Technology. After graduation, he joined Bell Telephone Laboratories—a leading technology company in those days—to design military devices.

In the winter of 1942, my great-grandfather traveled to upstate New York to visit his parents for Christmas. That year had been a trying one for the Allies: Nazi Germany occupied most of Europe, from France to western Russia. And America—which had been in the war for only a year—already faced intense naval battles in both the Pacific and Atlantic oceans.

Raymond W. Ketchledge

With 1943 on the horizon, the stakes in the Atlantic could not have been higher. In Western Europe, Britain stood alone against Germany, and the island nation relied on food, weapons, and other supplies from America. German U-boats, which often hunted in groups called “wolf packs,” sank hundreds of Atlantic merchant ships carrying those supplies to Britain. Without them, Britain–already under enormous strain from years of war—faced collapse. Indeed, Winston Churchill would later write that “the only thing that ever really frightened me during the war was the U-boat peril.”

That Christmas in 1942, my great-grandfather, age 23, sat with his parents at their home in the Adirondack Mountains. His father commented on the dire situation in the Atlantic. “We’re losing so many ships to the U-boats,” he said. “Britain is in trouble.”

My great-grandfather’s reply was simple: “That’s going to change soon.”

When asked what he meant, he could answer only vaguely: “I invented something.”

On both counts, he was right. The Battle of the Atlantic would soon turn in the Allies’ favor, and in no small part because of my great-grandfather’s invention. At Bell Labs, he had built the first acoustically-guided torpedo for use against enemy submarines. The “Mark 24 mine,” as it was called (the name was deceptive to hide its true purpose) had a design revolutionary for its time: it contained four hydrophones that could hear a submarine’s propellers and automatically steer the torpedo towards them–both in direction and in depth. And the battery-powered torpedo traveled faster than any submarine could while submerged.

Mark 24

My great-grandfather was there when the Navy tested the Mark 24’s first prototype, off the coast of Connecticut. The admiral on board the ship saw the torpedo in action and immediately ordered it rushed into production. Over the next 18 months, the Mark 24 sank dozens of German and Japanese submarines, which helped the Allies defeat the “U-boat peril” in the Atlantic and ensure Britain’s survival.

Testing of the Mark 24

In the Pacific, another of my great-grandfather’s inventions likewise helped the war effort. Naval aviators, who took off from aircraft carriers in the open ocean, often got lost–especially after combat–and could not find their ships. Many ran out of fuel, crashed into the sea, and died. My great-grandfather invented a device that, using gyroscopes and dead reckoning, would always point back towards the carrier. It saved many of our pilots’ lives. He was always proud of that.

The first SOSUS array (in red)

His contributions to the Navy continued after World War II. During the early Cold War, the Navy contracted again with Bell Labs, this time to develop a system of hydrophones on the seafloor. It was called the Sound Surveillance System, or SOSUS. The Navy deployed the hydrophones under the unclassified cover story “Project Caesar,” which purported to be an ocean survey program. SOSUS’ true purpose–to track Soviet submarines–was so secret that only a few people knew about it. My great-grandfather revealed in his later years that he had led Bell Labs’ work on SOSUS.

One of many people who benefited from SOSUS is my aunt, Lori (Ketchledge) Strasius. As an enlisted Navy intelligence specialist, she was stationed at the Naval Air Station in Keflavik, Iceland during the late 1980s and early 1990s. Although the Navy no longer uses that base, it was crucial back then because of Iceland’s proximity to Soviet submarine traffic in the north Atlantic.

My aunt, then-IS3 Lori Ketchledge, in Iceland

Every time my aunt was on watch in the SCIF, often at night, she used SOSUS–her grandfather’s invention–to track Soviet submarines and predict their movements. She would then brief the P-3 pilots stationed at Keflavik, who would go out hunting for the subs. SOSUS’ exact capabilities are still classified, but we do know that it was crucial for the Navy’s mission to counter the Soviet submarine threat.

NAS Keflavik, Iceland

Finally, in 1987, as my great-grandfather lay dying of cancer in Florida, he shared some final thoughts with his son, my granddad. He talked about the pilots’ lives his homing device had saved, the Mark 24’s success, the German lives lost, and the security that SOSUS had brought to the United States.

My great-grandfather then said that there was one other thing he had done that was hugely successful. It had become very important, he said, and was a major US intelligence coup. He added that his role was key in this project, and that it had brought him great pride. My granddad asked him what it was. Even on his deathbed, my great-grandfather still could not say. Whatever the project was, it was highly classified.

Many years later, my granddad was reading a book called Blind Man’s Bluff. It described a certain operation that had occurred during the Cold War. When my granddad read about it, he knew this was the project that his father had hinted about, but could not describe in detail, in the last days of his life.


In the 1970s, the United States undertook one of the most daring and effective intelligence operations of the Cold War. The Soviets had a communications cable on the ocean floor near the Kamchatka Peninsula, in the Russian Far East. This cable connected the Soviet Pacific Fleet’s headquarters at Vladivostok, to the west, to another major naval base on the Peninsula itself.

This region was treacherous for any US Navy operation. But the government decided that the potential benefit of tapping the Soviet cable outweighed the risk. Once again, they tasked Bell Telephone Labs to build a device for this task. By then, my great-grandfather was director of military systems at Bell Labs. They quickly got to work, and soon produced a device to eavesdrop on the Soviet cable.

Without piercing the cable, the device, which was about 20 feet long, would pick up on the cable’s magnetic emanations–which contained spoken conversations–and record those conversations on large reels of tape. Navy divers from the USS Halibut, a submarine specially modified for this mission, attached the tap to the cable in about 400 feet of water.

 Thereafter, American submarines visited the site every month, where divers removed the tape reels and replaced them. The Navy then sent the recordings to the NSA for processing. As the cryptologists there soon discovered, the Soviets were so oblivious of our snooping that most of their conversations through the cable were not even encrypted. And many of those conversations were between senior Soviet military officers. The operation, known as Ivy Bells, went on for years. It produced a wealth of intelligence about everything from the Soviets’ submarines to their ballistic missiles.

Tragically, Ivy Bells was compromised in 1981 after Ronald Pelton, an NSA employee in heavy debt, walked into the Soviet embassy in Washington and told them everything he knew about the operation. In return, he received $5000. (The government later convicted Pelton of espionage in federal court.) Shortly after this betrayal, American satellites spotted a group of Soviet ships anchored over the cable tap site. When an American submarine returned there later, the device was gone. The Soviets had taken it.

Betrayal by Ronald Pelton

In one respect, though, the Americans got the last laugh. When the Soviets pulled the cable tap out of the water, they would have opened it up and found the following words written inside: “PROPERTY OF THE UNITED STATES GOVERNMENT.”

I never got to meet my great-grandfather, but I did grow up hearing these stories. It is my honor to share the memories and contributions of a man who, through his talents and his love for his country, did much to keep the world safe–and who shaped history along the way.