With oxygen running low, search for missing submersible grows desperate

The search for the missing submersible on an expedition to view the wreckage of the Titanic passed the critical 96-hour mark Thursday when breathable air could have run out, a grim moment in the intense effort to save the five people aboard.

The Titan submersible was estimated to have about a four-day supply of breathable air when it launched Sunday morning in the North Atlantic — but experts have emphasized that was an imprecise approximation to begin with and could be extended if passengers have taken measures to conserve breathable air. And it’s not known if they survived since the sub’s disappearance.

Rescuers have rushed ships, planes and other equipment to the site of the disappearance. On Thursday, the U.S. Coast Guard said an undersea robot sent by a Canadian ship had reached the sea floor, while a French research institute said a deep-diving robot with cameras, lights and arms also joined the operation.

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Authorities are hoping underwater sounds might help narrow their search, whose coverage area has been expanded to thousands of miles — twice the size of Connecticut and in waters 2 1/2 miles (4 kilometers) deep.

The Titan was reported overdue Sunday afternoon about 435 miles (700 kilometers) south of St. John’s, Newfoundland, as it was on its way to where the iconic ocean liner sank more than a century ago. OceanGate Expeditions, which is leading the trip, has been chronicling the Titanic’s decay and the underwater ecosystem around it via yearly voyages since 2021.

By Thursday morning, hope was running out that anyone on board the vessel would be found alive.

Many obstacles still remain: from pinpointing the vessel’s location, to reaching it with rescue equipment, to bringing it to the surface — assuming it’s still intact. And all that has to happen before the passengers’ oxygen supply runs out.

Dr. Rob Larter, a marine geophysicist with the British Antarctic Survey, emphasized the difficulty of even finding something the size of the sub — which is about 22 feet (6.5 meters) long and 9 feet (nearly 3 meters) high.

“You’re talking about totally dark environments,” in which an object several dozen feet away can be missed, he said. “It’s just a needle in a haystack situation unless you’ve got a pretty precise location.”

The area of the North Atlantic where the Titan vanished Sunday is also prone to fog and stormy conditions, making it an extremely challenging environment to conduct a search-and-rescue mission, said Donald Murphy, an oceanographer who served as chief scientist of the Coast Guard’s International Ice Patrol. The passengers are also facing temperatures just above freezing.

Meanwhile, newly uncovered allegations suggest there had been significant warnings made about vessel safety during the submersible’s development.

Broadcasters around the world started newscasts at the critical hour Thursday with news of the submersible. The Saudi-owned satellite channel Al Arabiya showed a clock on air counting down to their estimate of when the air could potentially run out.

Retired Navy Capt. Carl Hartsfield, now the director of the Woods Hole Oceanographic Systems Laboratory, said the sounds have been described as “banging noises,” but he warned that search crews “have to put the whole picture together in context and they have to eliminate potential manmade sources other than the Titan.”

The report was encouraging to some experts because submarine crews unable to communicate with the surface are taught to bang on their submersible’s hull to be detected by sonar.

The U.S. Navy said in a statement Wednesday that it was sending a specialized salvage system that’s capable of hoisting “large, bulky and heavy undersea objects such as aircraft or small vessels.”

The Titan weighs 20,000 pounds (9,000 kilograms). The U.S. Navy’s Flyaway Deep Ocean Salvage System is designed to lift up to 60,000 pounds (27,200 kilograms), the Navy said on its website.