The clock is ticking Tuesday, as a search continues to find a submersible that vanished in the Atlantic Ocean, about 900 miles off the coast of Cape Cod.
Time is critical at this point, with experts saying there’s only enough oxygen on board to last until Thursday. U.S. Coast Guard Capt. Jamie Frederick said at a media briefing at 1 p.m. Tuesday that the sub only has an estimated 40-41 hours of oxygen left.
"Our thoughts and prayers are with the crew, their families and their loved ones," he said.
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The five people who were on board were on a voyage to see the wreckage of the Titanic, and the Coast Guard in Boston is heading up the multi-agency search for the OceanGate vessel.
Who is on the Titanic submarine?
New details are starting to emerge out about the five people who are on board.
British billionaire adventurer Hamish Harding is one of them, and he had been posting on social media about the trip leading up to it. Also in the submersible are Pakistani businessman Shahzada Dawood and his 19-year-old son, Sulaiman.
Sky News is reporting that it understands former French Navy Commander Paul-Henry Nargeolet – who’s led several previous expeditions to the Titanic site — and OceanGate’s CEO and founder Stockton Rush — who has insisted in previously published reports that these expeditions are safe — are both onboard as well.
Authorities have yet to formally identify those on board.
NBC News has not independently verified Sky News' reporting about Nargeolet being onboard. Nargeolet's stepson was unable to confirm whether or not he was actually onboard when reached overnight by NBC News. An Instagram post by Harding on Sunday did say that Nargeolet was due to be part of the expedition.
OceanGate’s expeditions to the Titanic wreck site include archaeologists and marine biologists. The company also brings people who pay to come along, known as “mission specialists.” They take turns operating sonar equipment and performing other tasks in the submersible.
OceanGate’s website described the “mission support fee” for the 2023 expedition as $250,000 a person.
Where is the Titanic wreckage?
Authorities reported the carbon-fiber vessel overdue Sunday night, setting off an international rescue effort in waters about 435 miles south of St. John’s, Newfoundland.
The search for the OceanGate Expeditions submersible is about 900 miles off the coast of Cape Cod, in water that's about 13,000 feet deep. Named the Titan, the vessel had about 96 hours of oxygen when it deployed around 6 a.m. Sunday for the company’s third annual trek to explore the wreckage of the Titanic, which sank 400 miles off the coast of Newfoundland, Canada, in 1912.
It lost communication about an hour and 45 minutes into the dive Sunday morning. It should take about two and a half hours to get down to the wreckage.
The search is taking place by water and air, they’ve also alerted commercial vessels in the area to keep an eye out as well.
“Right now we’re focused on locating the vessel, but at the same time, if we find this vessel in the water then we will have to effect some sort of rescue, or coordinating, reaching out to different partners within the US Navy, within the Canadian Armed Forces, and within private industry to understand what underwater rescue capability might be available," Rear Adm. John Mauger said, who is the First Coast Guard District Commander.
Titanic sub search details
Frederick said numerous resources have been deployed as part of the search, which has covered 7,600 square miles, an area larger than the state of Connecticut.
The search has covered the surface with sight and radar and subsurface with aircraft dropping and monitoring sonar buoys.
"To date, those search efforts have not yielded any results," Frederick said.
Additional vessels are continuing to arrive at the scene, and Canadian aircraft will be conducting searches Tuesday afternoon and evening, he said. A Canadian Coast Guard Cutter will be arriving Tuesday night, along with additional resources. The U.S. Navy is also sending a diving and salvage team.
"This is a very complex search," Frederick said. "We're working around the clock to bring all assets to bear in an effort to solve this complex problem."
"It's a unique operation, a challenging operation," he added.
What happens if the Titanic sub is found?
The question remains: If the sub is found, will there be enough time to rescue the occupants?
"We will do everything in our power to effect a rescue," Frederick said. "It's going to depend what they find what steps need to be taken next."
Experts said the rescuers face steep challenges.
Alistair Greig, a professor of marine engineering at University College London, said submersibles typically have a drop weight, which is “a mass they can release in the case of an emergency to bring them up to the surface using buoyancy.”
“If there was a power failure and/or communication failure, this might have happened, and the submersible would then be bobbing about on the surface waiting to be found,” Greig said.
Another scenario is a leak in the pressure hull, in which case the prognosis is not good, he said.
“If it has gone down to the seabed and can’t get back up under its own power, options are very limited,” Greig said. “While the submersible might still be intact, if it is beyond the continental shelf, there are very few vessels that can get that deep, and certainly not divers.”
Even if they could go that deep, he doubts rescuers could attach to the submersible.
The Associated Press contributed to this report.
