'Mr. Titanic' Was Aware of Sub Risks: 'You’re Dead Before You Realize That Something Is Happening'

Paul-Henry Nargeolet, one five people reportedly aboard the missing Titan submersible, has made more than 35 dives to the Titanic wreckage

<p>JOEL SAGET/AFP via Getty Images</p>

JOEL SAGET/AFP via Getty Images

French explorer Paul-Henry Nargeolet, one of the five people reportedly aboard the missing Titan submersible, was well aware of the dangers of deep-sea diving.

“If you are 11m or 11km down, if something bad happens, the result is the same,” he told the Irish Examiner in 2019. “When you’re in very deep water, you’re dead before you realize that something is happening, so it’s just not a problem.”

The former Navy captain, 77, is known as “Mr. Titanic” for his expertise and has been on over 35 dives to the Titanic wreck site, including the latest, according to The New York Times. He is the director of underwater research for RMS Titanic Inc., which is responsible for salvage efforts of artifacts from the ship site.

According to Bloomberg, Nargeolet also shared another risk when voyaging to the ocean’s floor, where the Titanic rests: He once told the Titanic Channel that the cold temperatures would be one of the greatest dangers if explorers became stuck at the wreckage site.

Related: &#39;About 40 Hours of Breathable Air&#39; Could Be Left on Missing &#39;Titanic&#39; Sub, Official Says

The Titan launched Sunday before communication was lost between the submersible and the Canadian expedition vessel Polar Prince “approximately 1 hour and 45 minutes” into the dive, U.S. Coast Guard Captain Jamie Frederick said at a press conference on Tuesday.

<p>Alamy Stock Photo</p>

Alamy Stock Photo

As the U.S. Coast Guard and Canadian Coast Guard continue their search and rescue mission for the vessel — which, if intact, could have about 40 hours of oxygen left, officials said Tuesday — loved ones fear for Nargeolet as well as the four other passengers.

Related: Everything to Know About the &#39;Titanic&#39;-Bound Submarine That Has Gone Missing

Pakistani businessman Shahzada Dawood and his son Suleman Dawood are on board, their family and King Charles' Prince’s Trust International confirmed to PEOPLE on Tuesday.

And according to ITV and the BBC, OceanGate CEO Stockton Rush and British billionaire Hamish Harding are also aboard.

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On Sunday, Nargeolet’s company wrote on Twitter that it sent “heartfelt support” to the search and rescue effort.

“We send our thoughts and prayers for the safe return of all on board,” officers with the RMS Titanic Inc. wrote.

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