Deepest submersible dive (Ocean)

Last updated: June 3, 2020 at 19:19 pm

10,925 m (35,843 ft) (verified by DNV GL) — Victor Vescovo (USA) aboard the DSV Limiting Factor (Triton 36000/2 model submersible) | Five Deeps Expedition, April 28, 2019 | ‘Eastern Pool’ of the Challenger Deep. Four hours (248 minutes) were spent on the bottom exploring the basin, which was also the longest period of time ever spent on the bottom of the ocean by an individual.

Between April 28 and May 5, 2019, the Limiting Factor completed four dives to the bottom of Challenger Deep and one final dive on May 7, 2019 to the Sirena Deep which is also in the Mariana Trench, approximately 128 miles to the northeast. Two of the dives, including the deepest one made on April 28, were solo dives piloted by Vescovo.

“It is almost indescribable how excited all of us are about achieving what we just did,” said Vescovo after arriving in Guam after the completion of the dives. “This submarine and its mother ship, along with its extraordinarily talented expedition team, took marine technology to an unprecedented new level by diving – rapidly and repeatedly – into the deepest, harshest area of the ocean. We feel like we have just created, validated, and opened a powerful door to discover and visit any place, any time, in the ocean – which is 90% unexplored.” — Victor Vescovo

On board the DSSV Pressure Drop for this historic accomplishment was legendary American oceanographer, explorer and marine policy specialist, Dr. Don Walsh (Captain, USN Ret.), who made the first successful decent into the Mariana Trench in 1960. The maximum depth achieved was measured and later corrected to be approximately 10,916 meters. “Victor Vescovo’s imagination and fierce curiosity; Triton Submarines technical brilliance, and the outstanding performance of the officers and crew of mother ship Pressure Drop all converged to make this expedition a huge success. And I was there to see it,” said Dr. Don Walsh (Captain, USN Ret.). “Nearly six decades ago Jacques Piccard and I were first persons to dive into Challenger Deep, the deepest place in the World Ocean. Then in 2012 James Cameron made a solo dive there. And now in 2019, ‘The Five Deeps Expedition’s submersible Limiting Factor was the third.”

Walsh continued, “This time it was an impressive tour de force as the team repeated the Challenger Deep dive four times in just eight days. This was a demonstration of system reliability and operational efficiency never seen before in exploration of the oceans’ deepest places. I was proud and honored to have been invited to be part of Victor’s team when it made world history at Challenger Deep.”

As with every other previous expedition dive, the team extensively measured and mapped the operating area with a Kongsberg EM124 sonar to pinpoint the desired dive sites. Once on the bottom, Vescovo or the two-person sub team of pilot and specialist usually spent 3-4 hours on the bottom conducting their survey and science missions. On average, it required 3.5 hours for the submersible to reach the bottom of the Challenger Deep and 3.5 hours to ascend. The average total mission duration lasted from 11-12 hours including one hour combined for launch and recovery of the sub from the surface, well under the submersible’s required life support endurance of four days with two persons onboard.

With his dives, Vescovo also became the first person to have summited Mount Everest and been to the bottom of the ocean, as well as having skied to both the North and South poles. Thus, he is the first to have completed visiting one version of the “Four Corners of the Earth”: Mt. Everest, Challenger Deep, and both geographic poles. In 2011, he completed the Seven Summits – climbing the highest peak on every continent – and has now been to the bottom of four of the world’s oceans.

DSV: Deep-submergence vehicle
DSSV: Deep-submergence support vessel

10,911 m (35,797 ft) — Bathyscaphe Trieste (Project Nekton) | January 23, 1960 | Challenger Deep (Mariana Trench), Guam. Hydrostatic pressure: 16,000 PSI (1,089 ATM). Occupants: Dr. Jacques Piccard (Switzerland), Lt. Donald Walsh, USN. The deepest known point on earth is 10,994 m (36,070 ft) (Also in the Challenger Deep). During their short time on the sea floor, Dr. Jacques Piccard sighted what appeared to be a flounder, thus potentially documenting the deepest fish ever observed. The fish identification has since been dispelled.

Caladan Oceanic — DSV Limiting Factor
Five Deeps Expedition
Piccard, Jacques and Dietz, Robert S. 1961. Seven Miles Down; The Story of the Bathyscaph Trieste. G. T. Putnam’s Sons.
U.S. Navy Office of Naval Research
DNV GL (Det Norske Veritas Germanischer Lloyd)

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