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Manned Submersible Slated to Travel to the Ocean’s Extreme Deeps

DSSV Pressure Drop lowers Limiting Factor.

DSSV Pressure Drop lowers Limiting Factor.

This is Trieste on the bottom, Challenger Deep. Six three zero zero fathoms. Over.”

The year was 1960, and U.S. Navy Lieutenant Don Walsh was calling in. At some 36,000 feet, he and Swiss oceanographer and engineer Jacques Piccard had just arrived where no one had ever been: our planet’s deepest point, the Challenger Deep in the Pacific Ocean’s Mariana Trench.

Since then, 12 humans have walked on the moon and hundreds have traveled in space, but only one other person, filmmaker James Cameron, has visited the Challenger Deep. And, each of the two manned submersibles that ventured there—Trieste in 1960 and Deepsea Challenger in 2012—only went once.

Now, Triton Submarines of Sebastian, Florida, has created a manned submersible that reportedly can travel to the ocean’s extreme depths again and again. Much like the space shuttles that repeatedly   delivered astronauts and equipment to the International Space Station and back to Earth, the Triton 36000/2 is intended to shuttle humans to what is arguably a realm even more remote, inhospitable and mysterious.

Victor Vescovo

Victor Vescovo

The sub and its mothership, a heavily modified research vessel, are keystones of the Five Deeps Expedition, the brainchild of extreme explorer Victor Vescovo. He has already climbed the seven highest peaks on the seven continents, as well as completed skiing expeditions to the North and South Poles. Now, he wants to be the first man to travel to the five deepest points in the Earth’s five oceans: the Challenger Deep in the Pacific; the Puerto Rico Trench in the Atlantic; the South Sandwich Trench in the Southern Ocean; the Java Trench in the Indian Ocean; and the Molloy Deep in the Arctic.

Limiting Factor submerges.

Limiting Factor submerges.

It is, Walsh says, “one of the most ambitious exploration expeditions of the century.” Crucial to its success is the Triton 36000/2, Limiting Factor. Built of titanium, the pressure hull is 3.54 inches thick and was tested at the Krylov State Research Center in St. Petersburg, Russia, to withstand a depth 20 percent greater than full ocean depth. With a surface weight of only 11.2 tons, it’s significantly lighter than earlier deep-diving submersibles, and with a design that maximizes vertical movement through the water column, the sub can reach the bottom of the Challenger Deep in less than two and a half hours. According to Triton, it is the first full-ocean-depth submersible that the classification society DNV GL has certified for repeated dives. Along with testing one man’s will and deep-sea technology’s limits, Triton’s submersible also is expected to provide a window into the study of one of the Earth’s least known, yet critically important, ecosystems. As Patrick Lahey, cofounder and president of Triton put it, “The submersible, together with the unique and specially equipped support vessel DSSV Pressure Drop, promise to change our relationship with the deep ocean in a profound and fundamental way.”

This article originally appeared in the January 2019 issue.



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