Trieste's Voyage to the Deep
You stare into the black abyss where no man has gone before, hoping for some sign of life as you continue to descend further into the gaping maw of the Earth. Sitting inside the cramped bubble you glance over at your partner who is also staring out the tiny window, the hum of electrical gauges and hiss of pressure sensors form a shallow rhythmic pattern before drifting out of tune with one another. Suddenly the cabin violently shakes and a loud cracking noise cuts through mechanical whirring! In wide eyed horror the two of you frantically search for the cause, all the while hoping that the next few moments won’t be your last.
The bathyscaphe Trieste. Courtesy of the U.S. Naval History and Heritage Command.
The Trench
The Marianas Trench is the deepest known spot in the world. Located in the Pacific Ocean it was formed at a convergent tectonic plate boundary, a boundary where one tectonic plate pushes another into the Earth’s crust. In this case the Marianas Plate is pushing the Pacific Plate into the crust and at this boundary where the two meet is where the Marianas Trench was formed. Within this trench is a valley that runs deeper than the trench itself, Challenger Deep, and it is the deepest known point in the world. In this spot it is so deep that if Mount Everest was placed at the bottom then it would be two kilometers short of the surface.
Diagram of how a convergent boundary works. Courtesy of Geogrify.
Challenger Deep lies beyond the Abyssal zone, the deepest zone in most oceans, and extends into what is known as the Hadal zone. This is a zone that ranges from 6,000 meters down and is the deepest sector of the ocean. In this region there is no light as the sun's rays cannot penetrate to these depths, it is pitch black and the pressure is so immense that it exceeds one thousand pounds per square inch. Reaching these depths is almost as difficult as space travel, and is just as alien.
Diagram of ocean zones. Courtesy of Sea and Sky.
The Vessel
Professor Auguste Piccard was a Swiss scientist who invented the bathyscaphe submersible. Best known for his work with buoyancy in regards to balloons, he set the world record for highest altitude balloon flight in 1931-1932. In 1933 he went to the World’s Fair in Chicago to display his high altitude balloon and it is there that he encountered a bathysphere, a precursor to the bathyscaphe, and became enamored with deep sea exploration. Unfortunately World War Two interrupted his research and Piccard had to wait until 1946 to start building his new vessel.
Auguste Piccard. Courtesy of Wikimedia Commons.
Unsurprising considering his past research, the basic idea for this new type of vehicle was similar to how a balloon works, and would be made up of two main sections. The top section would be like the actual balloon, a large hollow steel tank that would be filled with gasoline. Gasoline was used because it is more buoyant than water and is resistant to compression which makes it an ideal candidate for deep sea dives since it maintains an equal pressure. On either side of the gas tank were air tanks that could be pumped full of water to act as a ballast and allow the craft to sink. In addition to the water ballasts it would also have two hoppers filled with iron pellets that would add weight and allow it to sink. The pellets would be held in place by an electromagnet and when they needed to be released then power to the magnet would be cut off, thus allowing the gasoline to lift the craft up. The large tank would also have halogen floodlights attached so that the occupants could see in the dark depths. The second part of the submersible consisted of a sphere that hung at the bottom of the large tank, similar to the gondola on a balloon. This small steel sphere was where the occupants would work and do observations out of. It had a small plexiglass viewing port that was used to look out into the ocean and another one at the top that was used to enter the sphere. The entrance went through the middle of the gas tank and when the craft submerged the corridor would be flooded and have to be flushed out with compressed air once the crew surfaced. The vessel was not fast and really could not move much aside from going up or down, the bathyscaphe was invented with one goal in mind, deep sea exploration.
Diagram of how a bathyscaphe, specifically the Trieste, works. Courtesy of U.S. Naval Historic Center.
Piccard built two models that he and his son, Jacques Piccard, tested. The first built in Belgium between 1946 and 1948 was named FNRS 2. Unfortunately it was damaged soon after its completion in 1948 during trials in the Cape Verde Islands. The vessel was quickly rebuilt, improved, and renamed FNRS 3. It performed a number of excellent dives down to 4,000 meters, so with the idea now successfully tested Piccard set to building an even better model. On August 1, 1953 the Trieste, named after the city it was built in, was launched and with ease dived to a depth of 3,150 meters. In order to understand the importance of these depths one must keep in mind that most submarines during this time were only operating in depths between 200 and 280 meters. Auguste Piccard and his son continued testing their craft as they searched for someone to fund their research. In 1958 the United States Navy purchased Trieste and designed a new sphere that could be used to explore deep sea trenches. This new sphere was made of 5 inch thick steel that weighed over 14 tons, now making it necessary to lengthen the gas tank had to account for the increased weight. The Navy was interested in studying how deep sea pressure, sound, and temperature were affected at great depths, as well as mapping the ocean floor for strategic purposes. In fact by 1958 the US Navy was funding roughly 90% of all oceanographic related ventures in the United States and they were not going to let a chance to explore the deepest part of the ocean slip away from them.
The FNRS 2. Courtesy of the FNRS Society.
The Men
Two men would make the trip in Trieste to the bottom of the ocean, Jacques Piccard and Don Walsh. Jacques Piccard was a Swiss physicist, oceanic engineer, and economist who was son to famous Professor Auguste Piccard. Between 1944 and 1945 he took a break from his studies to serve in the French First Army during World War Two. After returning from the war he helped design the Trieste with his father, and after helping build and test the submersible he went to the United States in 1956 to try and find a buyer. The US Navy purchased it two years later and Piccard met Don Walsh.
Jacques Piccard. Courtesy of Wikimedia Commons.
Don Walsh was a Lieutenant in the Navy and had been interested in the ocean most of his life. He became an engineer while in the service and worked on submarines, becoming one of the most experienced at the time. In 1959 he became officer of the Trieste, and him and Piccard began testing the vessels capabilities and performing underwater tests in the Pacific.
Don Walsh. Courtesy of the National Geographic Society.
The Dive
For four days the US Navy tugboat Wandank had towed the Trieste 220 miles from its staging base on the Island of Guam to the trench. As they proceeded further and further out to sea the weather conditions and ocean surf became rougher and made the men begin to doubt their voyage. In the early morning hours of January 23, 1960 they reached the spot they were to dive. For the past two days a Navy destroyer had detonated more than 800 TNT explosion underwater in order for them to find the Marianas Trench and Challenger Deep, there were existing undersea maps but they were old and likely inaccurate. When the men reached the spot marked by the destroyer they were disheartened to find that several of their scientific instruments had been damaged during the towing. The surface telephone, the device used by the Trieste’s captain to communicate during the launching process, was torn away and inoperable. The tachometer, a device that measures the speed of descent and ascent, was completely destroyed, it had weathered over 50 dives without mishap. Finally the vertical current meter that measures the waters velocity was broken and barely clinging to its supports. It looked like they might not perform the dive so the crew set about repairing what they could.
Don Walsh and Jacques Piccard standing on Trieste’s deck. Public Domain.
They now had a choice to make, go ahead with the dive despite not being able to use some of their most important, though not vital, equipment, or let all their hard work go to waste and return to Guam. Structurally the craft itself was perfectly fine and all the electrical circuits were working so they would be able to release the ballasts and use the lights. Still, Piccard was nervous and did not want to perform the dive in such unfavorable conditions but Walsh being the one in charge said he would make the dive with or without him, inviting the Trieste’s engineer to come along if Piccard did not. Piccard promptly followed and began preparations. They made final checks and created impromptu signals for the crew since the Trieste now lacked a surface telephone, the undersea telephone would be used once they were below the waves. The sun began to rise and the sea worsened, tossing the Trieste and other ships in the area all about. The two men now wanted nothing more than to dip below the waves and escape the awful quake that was tossing their balloon like vessel around.
Trieste sitting on top of the water. Courtesy of Naval Historic and Heritage Command.
Quickly they climbed into the sphere and sealed the hatch behind them. Only a single bolt was used to hermetically seal them in, the thousands of pounds of pressure outside would ensure it stayed shut. At 0823 hours they began their dive and the Trieste became calm for the first time in days as it slipped below the waves. Though the nerve wracking task of descending to depths never seen before lay in front of them, they were somewhat happy to be in this position so they did not have to experience the waves and storms that the remaining crew would. The bathyscaphe slowly descended, only reaching 300 feet in 10 minutes but this was by design so the men could do any final checks that were needed.
Unfortunately an issue had already risen, they had reached the level where water cooled rapidly and completely halted their descent. In cooler water the relative weight of the craft was diminished so it would no longer sink. There were only two options, wait for the gasoline to cool to the outside water temperature or release some gasoline to bring down their weight. Both options held risks. Waiting meant that they might disrupt their timeline and it was imperative that they returned to the surface while it was still daylight. However if they released some of the gasoline then they might not have enough left to make their return to the surface. After a minute of deliberation the men decided to release some of the liquid. They were confident that their fuel calculations were correct and would not need the extra 150 cubic feet of extra gas they had brought along. After releasing their reserve they would have 4,000 cubic feet of gasoline left to lift them to the surface. Piccard opened the gas valve to allow some of the fuel to escape and after about a minute they began to descend once again. The valve was closed to keep what they could of the reserve tank but after descending only 35 more feet they hit another layer of cooler water and were halted again. More gas was released to resume the dive. Five minutes after this second halt, at a depth of 425 feet, they were stopped once more by another layer and had to release even more fuel. Seven minutes later they were stopped again at a depth of 530 feet and had to release more of the precious liquid. Jacques later stated that “This was the first time in my 65 dives in the Trieste that I had observed this phenomenon of repeated stratification.”
There was an upside to all of these stops however, they were able to watch their new electric thermometer and accurately take temperatures of the thermocline. This information would be helpful to oceanographers in defining the different temperature zones of the ocean.
After diving 650 feet the problems appeared to be over as the men were now descending at a steady rate of four inches per second. The true dive was just now beginning as they had nearly seven miles to go. Luckily as the men continued to dive deeper and deeper the increased pressure would add weight and cause them to descend faster, eventually coming to a mean speed of three feet per second. The only time Piccard or Walsh would interfere with the process was when they released ballasts to ensure they were traveling at a safe speed.
Piccard and Walsh sitting inside the Trieste. Courtesy of Wikiwand.
At 1,500 feet the ocean was already pitch black and they turned on a small light inside of the sphere, just bright enough for them to read their instruments. The temperature was dropping rapidly so the men decided to put on their dry clothes as they had both been soaked by ocean spray when entering the craft. All precautions were taken to ensure the men stayed warm as they would basically be sitting motionless for nine hours with little chance to move around.
A little further down they began to see phosphorescent plankton appearing. The searchlight was rarely used during the descent as they wanted to observe these luminous creatures, but were a bit disappointed as they only saw them around 2,200 feet and 20,000 feet. The men were not seeing much life at all on their descent, describing the depths as “extraordinarily empty”. However they theorized that the presence of the bathyscaphe may have disrupted the natural habitat and caused many fish and other creatures to disappear. Piccard later went on to say that he rarely saw fish during a rapid descent and even when travelling at a creep it was rare to see anything other than plankton or other “relatively primitive species.”
Trieste. Courtesy of Factinate.
The men had planned on allowing the bathyscaphe to descend at a rate of three feet per second until they hit 26,000 feet, at that point they would slow to two feet per second. They would continue at two feet per second until 30,000 feet and then reduce even further to one foot per second, this would allow sufficient time for them to slow down before hitting the bottom. Of course there was always a danger of a deep sea current sweeping them off course or landing on a hard slope of the trench. In order to avoid these catastrophes and control the speed of the craft the men had to continually check the outside water temperature, the gasoline temperature, the quantity of ballasts still available, and, likely most important of all, the pressure at the exact time and depth. They also were constantly checking the humidity, oxygen percentage, carbon dioxide and temperature inside their sphere while also taking notes that would be used for research after they returned to the surface. Piccard and Walsh later said that all this work made the five hour descent go by rather quickly.
At 5,600 feet, an hour after the dive began, the men received a phone call from the surface. Buono, the Trieste’s engineer, on the surface assured the men that despite the less than favorable wave and weather conditions everything went as planned. They received another phone call at 10,000 feet and a third at 13,000 feet. It was difficult to tell whether they would be able to maintain contact for the duration of the dive but for the best chances it was paramount that the surface crew to stay directly above the Trieste, not an easy task in rough seas.
Past 24,000 feet the men were in virgin territory, no one had ever been to these depths before. It was the fourth time the Trieste had broken the deepest diving record, a craft built to withstand any depth had served well. However they were still not at the bottom and had quite a ways to go. They continued to 26,000 feet and were still able to hear conversations between the tugboat and their Naval escort over the telephone.
At 1130 hours they reached 30,000 feet and slowed to one foot per second. The pressure outside squeezed the bathyscaphes walls with 150,000 pounds of force, if the men were not protected by the steel sphere then they would be crushed instantly. The water at that depth was extremely dead and they saw no signs of life. For a quick moment the spotlight was turned on and its beam penetrated the waters below, but no sign of the bottom could be seen. Piccard said, “We are in the void, the void of the sea”. By this point they had turned on the sonic depth finder and were expecting to reach their goal at any moment. The searchlights were switched on once more but still no appearance of the sea floor. Ever so often ballasts were dropped to slow their gradual descent; time seemed to move extremely slowly as they waited for the bottom to rise out of the opaque abyss.
The Trieste being lifted into the water. Courtesy of Britannica.
All of a sudden at 32,500 feet the sphere was overtaken by tremors and the men were petrified to hear a dull cracking noise coming from their battered craft. The men looked at each other, both worried and confused as to what it might be. At first they thought they had hit bottom but that idea was quickly thrown out as the depth finder did not show anything and looking out the viewport they could see they were still descending. For a moment they theorized they may have even met a large sea creature unknown to them, a veritable sea monster. All systems inside were still running normally, the gauges were all working, there was no change in the bathyscaphes equilibrium, and they were descending at a steady rate. They were not sure what to think. They turned off everything on board that made a noise, humming electronic instruments, hissing oxygen gauges, all of it was silenced as they attempted to discover the origin of the cryptic noise. In the quiet depths all they could hear was “tiny crackling sounds, like ants in an ant hill, little cracking sounds coming from everywhere, as if the water were being shattered by our passage.” The men theorized everything from small shrimp hitting the outside of the sub to the outer paint cracking under the enormous pressure. Fortunately they were still descending at a regular pace which was a great reassurance to both of them, and because of this, along with the fact that nothing was leaking, they decided to continue the descent and discover the origin of the sound later.
A few signs of life were now beginning to show themselves. Though they had a difficult time seeing them the men believed jellyfish were swimming around their viewport, not a surprise as they knew that there is bacteria and various other invertebrates that can survive at great depths. The real question to them was whether fish could survive under such pressure. They continued to descend and the telephone stopped picking up signals from the surface. Save for the hum of the instruments, everything was silent and time moved slowly as the men feverishly glanced back and forth out the tiny window then back at the depth finder, sure that they would be reaching the bottom soon. At 1256 hours the men saw the ocean floor on the depth finder, 300 feet below them was the bottom of the trench. It took them 10 minutes to traverse those 300 feet and at 1306 hours with a light thud they touched down on the pale sea floor. Indifferent to the close to 200,000 tons of pressure pressing against it, the Trieste quietly sat 35,797 feet at the very bottom of the Pacific Ocean. As luck would have it they set down just a few feet from a fish, not bacteria or an invertebrate, but a true fish. This answered a question that oceanographers and ichthyologists had asked for decades, could fish survive at such extreme depths under intense pressure? The answer was a resounding yes. The fish was flat, “like a halibut or sole”, measuring about a foot long and about half a foot wide. The men carefully watched as it slowly swam out of the garish spotlights and back into the dark void it knew so well. As the fish disappeared the white dust kicked up by their landing was beginning to obscure their view.
CGI of what the Trieste looked like on the bottom of the ocean. Courtesy of the National Geographic Society.
The two planned on staying at the bottom for 30 minutes and would try to record as much information as they could in that short amount of time. They took temperature readings, 38° F, attempted to find any sort of current, they discovered none, and checked for radioactivity, none. The two also spent several minutes peering out the viewport and watched as a lone shrimp fluttered past them in the tranquil water. To make sure they left nothing up to scientific curiosity, Walsh picked up the phone and skeptically called the crew on the surface, “This is Trieste on the bottom, Challenger Deep. Six three zero zero fathoms. Over.”
The men lit up as they heard “I hear you weakly but clearly. Please repeat the depth.” Slowly and articulately Don repeated the depth and they received another reply, “Everything O.K. Six three zero zero fathoms?”
Walsh again answered, “That is Charley. (Seamen's jargon for correct) We will surface at 1700 hours.”
“Roger” was the simple response from the surface. The two were elated after this conversation as they now knew that even at great depths they could maintain communication with those on the surface.
Picture that Piccard and Walsh took inside the Trieste after reaching the bottom. Courtesy of Don Walsh.
They had planned on staying on the bottom for 30 minutes before ascending. At around the 20 minute mark Walsh had Piccard swing the spotlight around to the rear viewport, and after peering out it for a few seconds he told Piccard that he knows what that jolt and cracking noise was earlier. The plexiglass viewport that the men used to enter the sphere had cracked in several places. This did not worry the men as the pressure would make sure the cracks did not leak, what worried them was if the cracks would prevent the entrance way from being drained once they reached the surface or if the window cover would need to be replaced by a spare. In such rough seas this would need to be done in daylight and if they did not reach the surface in time then they may have to stay in the cramped sphere even longer, a thought that appealed to neither of them. In order to try and prevent this unfavorable outcome the men reluctantly left for the surface 10 minutes early. Piccard flipped the electric switch that released the iron pellets that acted as ballasts and watched as a white cloud of gleaming dust engulfed the vessel. This dust was made of silica from the skeletons of dead sea creatures that fell to the bottom and reflected the spotlights rays back onto the craft. The men began their ascent to the surface, leaving the abyss in the utter darkness that had engulfed it for centuries.
The spotlights were kept on for much of the ascent and the two watched out the porthole but were still unable to see anything, the feeling of emptiness that they had felt on their descent was quickly being restored. Trieste’s ascent grew gradually as the pressure slowly decreased and allowed it to rise faster. At first just one and a half feet per second, then at 30,000 feet they were going two and a half feet per second, at 20,000 feet roughly three feet per second, and at 10,000 feet about four feet per second. Not long before they reached the surface they were traveling at about five feet per second but this was soon slowed as they reached warmer water and the weight of the craft was increased by about a ton. The Trieste performed flawlessly throughout the entire ascent, never rolling, tipping, or jolting through the whole returning voyage. Their instruments were the only indication that they were ascending as the ride was so smooth. It was still chilly in the cabin, about 40 °F, but sunlight was now beginning to enter through the viewports, they did not have much longer to go.
CGI image of the Trieste ascending. Courtesy of the National Geographic Society.
At 1656 hours the Trieste pierced the ocean's surface, completing the deepest dive man had ever made. The men now had to blast the water out of the corridor with compressed air so they could exit the craft. Usually the operation only took two or three minutes but because the plexiglass window was cracked they could not put too much pressure too fast, and it ended up taking 15 minutes for them to expel the water. A final challenge for the men who had been to one of Earth’s most treacherous places. As they climbed out of the sphere they were tossed about by the waves and high winds that had worsened since they had begun, but no amount of bad weather could break their spirits now. The two men stood on the top deck of the Trieste and were met by a noisy salute as several Navy jets and a jet from the Guam Air Rescue unit flew overhead and dipped their wings to greet the men. A few miles away the Wandank and the Navy escort ship were rapidly approaching to pick up the men and their craft. As the ship and boat greeted them they were overtaken by a crowd of photographers who kept yelling for the men to salute as they took pictures. In the words of Piccard, “ indeed, we saluted gladly; not for posterity, to be sure, not for the photographers, but for the rediscovered sun and pure air, even for the wind and the waves that submerged us each instant. We had only one thought: profound gratitude for the success achieved, gratitude toward all those who had contributed to the success of this uncommon day.”
The full crew of the Trieste posing in front of her. Courtesy of the U.S. Navy.
Afterwards
After the 1960 expedition the Trieste was taken by the US Navy and used off the coast of San Diego, California for research purposes. In April 1963 it was taken to New London Connecticut to assist in finding the lost submarine USS Thresher. In August 1963 it found the Threshers remains 1,400 fathoms (2,560 meters) below the surface. Soon after this mission was completed the Trieste was retired and some of its components were used in building the new Trieste II. Trieste is now on display at the National Museum of the United States Navy at the Washington Navy Yard.
The Trieste II. Courtesy of Cybernetic Zoo.
Jacques Piccard went on to continue designing submarines with his father, most notably the mesoscaphe class submarine which could carry multiple passengers. He also continued helping the US Navy perform underwater research, specifically with the Gulf Stream. In his later life he went on to work as a consultant for several private deep sea research companies. Jacques Piccard unfortunately passed away on November 1, 2008.
Jacques Piccard with some of his submersible designs in front of him. Courtesy of AFP.
After relinquishing command of Trieste in 1962, Don Walsh continued to work on submarines and became the commander of one in 1968. In 1975 he retired from the Navy and went on to become a professor of ocean engineering at the University of Southern California. Throughout the rest of his life he would speak about the ocean in TV and radio interviews and continue writing ocean related publications. His expeditions did not stop with the Trieste however as he would go on to make dives to deep sea vents, the wreckage of the R.M.S. Titanic and the battleship Bismarck along with going on polar expeditions in the Antarctic. Walsh would go on to obtain many prestigious awards from academic organizations, including the Hubbard Medal, National Geographics highest honor. At the time of writing this article he resides in Oregon where he is a courtesy professor at Oregon State University.
Don Walsh. Courtesy of the U.S. Navy.
Though there were a few unmanned submersibles to explore the Marrianes Trench, Jacques Piccard and Don Walsh remained the only two people to reach the deepest known part of the ocean until the DEEPSEA CHALLENGE expedition in March 2012. Canadian film producer and inventor James Cameron dove solo to the bottom of Challenger Deep. Don Walsh helped Cameron’s crew understand the unique challenges they would face at these depths. A brand new unique submersible was built for the voyage. This time the sub was outfitted for more indepth research as it possessed a robotic arm and other tools for collecting samples and specimens. It was also outfitted with 3D cameras that would take high quality video and audio of the surrounding area. Cameron spent a few hours on the ocean floor collecting data and samples and plans on making more trips in the future. All this being possible thanks to the sacrifice and determination that was made many years ago.
James Cameron’s submarine. Courtesy of the National Geographic Society.
Personal Thoughts
I have a love hate relationship when it comes to ocean exploration. On one hand it fascinates me, but on the other it terrifies me and I’ve been this way since I was little. I loved learning about the ocean but at the same time not knowing what all lives down there scares me quite a bit. I do really enjoy learning about deep sea expeditions like this however.
Something I kind of have to wonder is that they said they didn’t see much life when they were down there and I just can’t help but think that might have something to do with all the TNT they dropped beforehand.
Sources
Cover photo courtesy of Britannica
http://www.deepseachallenge.com/the-expedition/1960-dive/
https://geology.com/records/bathyscaphe-trieste.shtml
https://www.nationalgeographic.org/encyclopedia/bathyscaphe/
https://www.nationalgeographic.com/news/2012/3/120325-james-cameron-mariana-trench-challenger-deepest-returns-science-sub/
https://www.onr.navy.mil/en/About-ONR/History/tales-of-discovery/bathyscaphe-trieste
https://usnhistory.navylive.dodlive.mil/2015/01/23/bathyscaphe-trieste-overcomes-the-challenge-of-the-deep/
https://www.britannica.com/technology/bathyscaphe
https://www.navsource.org/archives/08/08554.htm
https://www.defense.gov/explore/story/Article/1737193/hitting-bottom-submariner-explored-deepest-part-of-ocean/
https://www.youtube.com/watch?v=AOfS-tzxZAs
