Undersea agriculture. Deep sea mining. Human colonies on the ocean floor. These were the dreams of Capt. George Bond, a Navy medical officer.
It was the age of exploration. While NASA made front-page headlines for its quest to send a man to the moon, Bond was quietly conducting groundbreaking experiments to see if humans could live and work on the ocean floor. As head of the Navy's "Man-In-The-Sea" program, Bond considered the ocean bottom humanity's next frontier.
For many, Bond's ideas sounded like fantasy. From ancient myths of sea monsters lurking below to Jules Verne's classic Twenty Thousand Leagues Under the Sea, the ocean has long been a source of fear and fascination. Around the same time Bond began his experiments, Jacques Cousteau's 1956 documentary The Silent World cultivated worldwide interest in ocean exploration. The documentary's pioneer underwater cinematography was captivating. But Bond's vision was more significant than just visiting deep waters; he wanted humans to live there.
Bond, who died in 1983, spoke publicly about these dreams. Radio Diaries unearthed a trove of archival audio material for this story.
The theory of saturation diving
In 1963, President John F. Kennedy addressed the National Academy of Sciences: "To a surprising extent, the sea has remained a mystery. We know less about the oceans at our feet than the sky above our head." Kennedy urged Congress to increase the budget for ocean research because. In a letter to the Senate he wrote, "Knowledge of the oceans is more than a matter of curiosity. Our very survival may hinge upon it."
Bond completely agreed. He believed the ocean held bountiful untapped resources and opportunities, and he became determined to find a way for humans to explore the ocean's floor.
Ben Hellwarth, author of Sealab, America's Forgotten Quest to Live and Work on the Ocean Floor, said when Bond joined the Navy in the 1950s, divers used compressed air to breathe and couldn't stay underwater for more than half an hour. This limited the type of work that could be conducted underwater.
Bond became determined to figure out a way to dive deeper, and stay underwater for longer periods of time. Bond and his colleague, Walt Mazzone, developed a theory called saturation diving. The idea is that if divers breathed the right combination of gases at deep depths, their bodies would become saturated and absorb the gases after about a day. Once the body becomes fully saturated with the gases at a specific depth, the amount of time it would take to decompress would be the same, whether divers were spending days, weeks or even months below the surface at that depth. Many in the Navy thought Bond's idea was far-fetched, but he pressed on.
Bond began testing his theory with laboratory experiments on animals and, eventually, humans. After a series of successful tests, Bond convinced the Navy to give him modest funds to build an undersea habitat, Sealab I, to be tested 200 feet down in the warm waters off of Bermuda. In 1964, four divers — called aquanauts — successfully lived in the undersea base for 10 days. A year later, a bigger habitat called Sealab II was submerged off the coast of La Jolla, Calif., for a more ambitious 45-day experiment at a depth of 205 feet in a much colder, murkier sea.
Space vs sea
Among the aquanauts was Scott Carpenter, a former astronaut from NASA's Project Mercury. Carpenter was fascinated by the sea. He fought for more funds for Sealab, which had a fraction of the budget as the space program.
"It was a mission he believed in," his daughter, Kris Stoever, told Radio Diaries. Carpenter believed that exploring the ocean, which covers three-quarters of the earth, would bring many benefits to humankind.
However, Carpenter acknowledged that underwater exploration didn't capture the public's imagination in the same way as the space program. "Work in the deep water is just not as glorious a pursuit in the minds of most people as a flight to the moon, for instance. It's a cold, dirty, place and you can't see very far. You can't go down and take pictures that thrill the world," he told CBS in 1968.
Living underwater
The Sealab structures looked like a submarine with legs and was designed to perch on the ocean floor. Its open hatch allowed divers to enter and exit freely. Water didn't rush in through the hatch because the pressure inside the vessel was kept the same as the water pressure outside.
There were three teams of aquanauts in Sealab II, each living in the habitat for 15 days. But Carpenter and one other aquanaut stayed down for 30 days. The aquanauts spent their days conducting a variety of scientific and technical experiments. They studied the physiological and psychological effects of prolonged underwater living, testing how the human body copes with pressure and gas mixtures over time. They also tested tools and techniques for underwater construction and salvage, laying the groundwork for future endeavors in deep-sea exploration and industrial operations.
At sea level, a Navy barge served as a mother ship — feeding the vessel gases, power and water from the surface. Bond, who stood on the barge often smoking a pipe, communicated with the aquanauts through an intercom and watched them through an underwater camera. People on land would lower supplies in protected containers. The Navy even trained a bottlenose porpoise named Tuffy to deliver letters. And on Sundays, Bond, a former lay preacher, would give a sermon through an intercom, which included his own "Sealab prayer."
Inside, the habitat resembled a modest RV, with basic amenities such as a shower, toilet, sink, dinner table, and shelves of canned food.
But living underwater wasn't without its quirks. The unique breathing atmosphere was high in helium and made the aquanauts' voices sound high-pitched, like Donald Duck. This made the aquanauts unintelligible. But it also provided some comic relief: Carpenter used his high-pitched voice for entertainment, playing "Goodnight Irene" on the ukulele.
Close calls
The ability to make continuous dives over weeks allowed the divers to witness marine life in ways that had never been done before. Living amid the underwater creatures was thrilling. "You could see these animals doing things undisturbed. They sort of got used to us," aquanaut Richard Grigg told reporters after he emerged from the Sealab in 1965.
And at times, the sealife also posed dangers. Carpenter was once stung by a venomous scorpionfish while outside the vessel.
The aquanauts' lives were precarious. An error in the mix of breathing gases could be fatal, and the atmosphere often caused headaches and earaches.
"Every minute and every hour, every day, there are obviously opportunities for something to go wrong, and there were close calls," said Hellwarth.
In one harrowing moment, Carpenter's air supply kinked, forcing him to make a desperate swim back to the habitat.
"None of this had ever been done before. We all felt like we were the lab rats. But we were all young, foolish, gung-ho and thought we were invincible," Richard "Blackie" Blackburn, a Sealab aquanaut, told Radio Diaries.
Stoever, Carpenter's daughter, said her father was willing to be a guinea pig, gathering data about what happens to the human body under duress. "He felt there's value in pushing yourself to the very extreme — what can human beings do," she said.
Bond's theory of saturation diving worked and Sealab II was considered a success. At the end of Carpenter's month living underwater, President Lyndon B. Johnson called to congratulate him on the achievement. No human had ever lived at that depth or sustained such an intense amount of water pressure for that long.
Project ends in tragedy
The success of Sealab I and II led the military, scientific community and private industry to have greater ambitions for undersea habitation. By 1969, the Navy built Sealab III, its biggest and most expensive habitat to date, with the intention of placing it at a depth of more than 600 feet off the California coast for two months. That depth and timeline were far beyond what any diver had experienced before.
On February 15, 1969, the Navy crew lowered Sealab III 610 feet below the surface and there were problems immediately. The lab began leaking its helium-rich artificial atmosphere. The Navy support barge had to pump increasing amounts of gas into the lab to maintain its pressure. If they couldn't fix the issue, the lab would flood, and the habitat would be lost. The Navy commanders sent a small team of aquanauts down to try to plug the leaks.
Blackburn and three other aquanauts, Bob Barth, Berry Cannon and John Reaves, donned their wetsuits and descended to the lab in a pressurized elevator called a personnel transfer capsule (PTC). As soon as they entered the PTC, they realized the heating system wasn't working.
"You get 10 times colder breathing helium than you do air. The cold was so bad that our bodies were shaking like we were in convulsions," Blackburn recalled.
The trip to the lab took about an hour. By the time they reached the bottom, the four aquanauts were freezing. Barth and Cannon left the PTC and swam out to the Sealab to fix the leaks. Blackburn and Reaves waited in the PTC.
After a few minutes, Blackburn and Reeves heard a strange scream, and immediately received an urgent command through the intercom. The Navy had set up a camera to monitor the aquanauts' work, and they saw Cannon struggling. Blackburn swam out and saw Cannon floating unconscious near the lab, his mouthpiece above his head. Blackburn grabbed Cannon and got him into the PTC with the other divers. But it was too late. Cannon was dead.
The Navy investigated Cannon's death. Ultimately, officials blamed Cannon's diving rig and the diver responsible for maintaining it.
"That was a conclusion that none of the divers agreed with," Hellwarth told Radio Diaries. The Navy canceled the entire project, deeming stationary underwater habitats too expensive and complicated to maintain. The Navy, instead, focused its resources on saturation diving.
Though Bond's dream of permanent undersea habitation never materialized, its legacy lived on. During the Cold War, the Navy built special compartments on submarines to act as mini habitats for saturation divers, so they could access Soviet deep-sea cables.
In his book, Hellwarth wrote that many of the aquanauts, including Blackburn, went on to work in the oil industry's offshore drilling operations, which depend on the expertise of saturation divers.
Today, scientists use saturation diving to study the ocean from the Aquarius Reef Base, a habitat 62 feet underwater off the Florida coast.
For the Sealab aquanauts, living under the sea was an unforgettable experience. Blackburn told Radio Diaries the ocean was an awe-inspiring place. "It got to be where you really wanted to be in the water more than you wanted to be on land because it was so much more peaceful and so much more beautiful."
This story was produced by Sarah Kate Kramer and the team at Radio Diaries. It was edited by Joe Richman, Ben Shapiro and Deborah George. Sonya Gurwitt assisted with archival research. You can find more stories on the Radio Diaries Podcast.
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