British Explorer on Missing Submersible Said He Knew the Risk of Such Voyages

Hamish Harding, a British explorer aboard the submersible missing in the North Atlantic, acknowledged in a 2021 interview that he had taken on deep-sea missions in the past knowing that rescue would not be an option.

“If something goes wrong, you are not coming back,” he told the Indian newsmagazine The Week after he made a record-setting trip to Challenger Deep, the furthest depths of the Mariana Trench. At almost seven miles, the Mariana Trench is far deeper than the Titanic site that the submersible was set to visit, which is about two-and-a half miles down.

On the 2021 trip, Mr. Harding, a 58-year-old British businessman, and Victor Vescovo, an American explorer, set a Guinness World Record for the longest time spent traversing the deepest part of the ocean on a single dive. Their 4-hour, 15-minute dive also set a record for farthest distance traveled along the deepest part of the ocean.

“It was potentially scary, but I was so busy doing so many things — navigating and triangulating my position — that I did not really have time to be scared,” Mr. Harding told The Week.

The vessel used for the Challenger Deep dive had a four-day oxygen reserve, as well as water and emergency rations, but was traveling so deep that no other sub “is capable of going down there to rescue you,” he said.

Mr. Harding — the founder and chairman of Action Aviation, a sales and air operations company based in Dubai — has also made airborne adventures. He flew to space last summer on a mission by Jeff Bezos’s Blue Origin rocket company and holds a record for the fastest circumnavigation of Earth via both the geographic poles by plane. And in 2022, he helped an effort to reintroduce cheetahs to India.

Action Aviation called Mr. Harding “an extraordinarily accomplished individual who has successfully undertaken challenging expeditions,” in a statement on Tuesday. The company added, “We look forward to welcoming him home.”

Mr. Harding wrote on his Facebook page on Saturday that he was proud to finally announce that he had joined OceanGate’s mission “on the sub going down to the Titanic.”

In an Instagram post with pictures of the submersible and of him signing a flag for the Titanic mission, Mr. Harding wrote that the group had sailed from St. John’s, Newfoundland, Canada, on Friday, and was planning to start dive operations around 4 a.m. on Sunday.

Despite the winter being particularly hard in Newfoundland this year, “a weather window has just opened up,” he added.

On Monday, the president of The Explorers Club, a New York-based organization of which Mr. Harding was a board member, alerted the club’s membership to the disappearance of the submersible that was carrying Mr. Harding and four others.

“When I saw Hamish last week at the Global Exploration Summit,” wrote the club president, Richard Garriott de Cayeux, “his excitement about this expedition was palpable. I know he was looking forward to conducting research at the site.

“We all join in the fervent hope that the submersible is located as quickly as possible and the crew is safe.”