Sean Leet, left, chairman of Horizon Maritime Services, stands with Chief Mi'sel Joe of the Miawpukek First Nation, at a news conference at the harbour in St. John's, Wednesday, June 21, 2023. Underwater noises described as “banging” have been heard in an area of the Atlantic where a submersible disappeared three days ago near the wreck of the Titanic, search officials confirmed Wednesday. THE CANADIAN PRESS/Sarah Smellie

Search for missing Titanic submersible expands as oxygen supplies deplete

The search intensified Thursday for a small submersible lost in the depths of the North Atlantic Ocean as the oxygen supply for the five people trapped inside the vessel was believed to be in its final hours.

Two more remotely operated vehicles dived into the water Thursday morning to join the search for the Titan submersible, according to tweets from the United States Coast Guard. An ROV deployed by the Canadian vessel Horizon Arctic had reached the ocean floor at the site of the Titanic shipwreck to look for the Titan, and another from the French vessel L’Atalante was en route.

The Titan lost contact with surface vessels on Sunday as it was diving to reach the famous wreck. There were five people on board including Stockton Rush, chief executive officer of OceanGate Expeditions, the company that owns and operates the Titan.

Officials have said the minivan-size submersible has an air supply that can last four days, which means the supply could run out on Thursday.

The search is being carried out about 700 kilometres off the southeast coast of Newfoundland, near a renowned fishing area known as the Grand Banks. Winds in the area Thursday morning were gusting up to 30 kilometres an hour, and swells were more than a metre high, the coast guard said.

American authorities have said “banging sounds” had been detected in the search area, though the cause was unclear.

The Titan is not “classed,” or certified, and experts have had concerns about it for years. A certified vessel has been scrutinized by a recognized third-party to ensure it was designed, constructed and tested according to safety standards, said William Kohnen, president and CEO of the California-based engineering firm Hydrospace Group.

About 95 per cent of all submersibles are certified, he said in an interview earlier this week. Titan, he said, “is very much an outlier.”

Kohnen was part of a group of engineers and industry professionals who wrote to Rush in 2018 to express their concern. Their letter, first obtained by the New York Times, warned that the company’s “experimental” approach to Titan could have “catastrophic” consequences.

In a 2019 blog post, OceanGate explained that Titan was not classed because the classification process could inhibit innovation and did not address pilot error, which it said are the cause of most marine accidents.