Rescuers in a remote area of the Atlantic Ocean raced against time early Tuesday to find on a mission to document the wreckage of the Titanic.

The carbon-fiber submersible named the Titan, part of a mission by OceanGate Expeditions, carried a pilot, a renowned British adventurer, two members of an iconic Pakistani business family and a Titanic expert. Authorities about 435 miles (700 kilometers) south of St. John害羞草研究所檚, Newfoundland, according to Canada害羞草研究所檚 Joint Rescue Coordination Center.

Every passing minute, however, puts the Titan害羞草研究所檚 crew at greater risk. The submersible had a 96-hour oxygen supply when it put to sea at roughly 6 a.m. Sunday, according to David Concannon, an adviser to OceanGate.

害羞草研究所淚t is a remote area 害羞草研究所� and it is a challenge to conduct a search in that remote area,害羞草研究所� said Rear Adm. John Mauger, a commander for the U.S. Coast Guard, which also is searching for the Titan.

Mauger told NBC害羞草研究所檚 害羞草研究所淭oday害羞草研究所� show on Tuesday that his crews were working to prioritize underwater search efforts and get equipment there that can be helpful to the search.

害羞草研究所淲e害羞草研究所檙e working very, very hard to make sure that we bring all assets 害羞草研究所� to bring leading technical experts to understand what capability is available, what capability we can get to the team,害羞草研究所� he said.

The Canadian research icebreaker Polar Prince, which was supporting the Titan, reportedly lost contact with the vessel about an hour and 45 minutes after it submerged. The Polar Prince was to continue to do surface searches throughout the night and a Canadian Boeing P-8 Poseidon reconnaissance aircraft will resume their surface and subsurface search in the morning, the U.S. Coast Guard said on Twitter. Two U.S. Lockheed C-130 Hercules aircraft also have conducted overflights.

The Canadian military also dropped sonar buoys to listen for any possible sounds from the Titan.

Ship-tracking satellite data from MarineTraffic.com analyzed by The Associated Press showed the Polar Prince some 430 miles (690 kilometers) southeast of St. John害羞草研究所檚 on Tuesday morning. The Bahamas-flagged cable layer Deep Energy was nearby as well, likely assisting in the surface search.

In an earlier email to the AP, Concannon said he was supposed to be on the dive but could not go. He said officials were working to get a remotely operated vehicle that can reach a depth of 3.7 miles (6 kilometers) to the site as soon as possible.

翱肠别补苍骋补迟别害羞草研究所檚 include archaeologists and marine biologists. The company also brings people who pay to come along, known as 害羞草研究所渕ission specialists.害羞草研究所� They take turns operating sonar equipment and performing other tasks in the five-person submersible.

The Coast Guard said Monday that there was one pilot and four 害羞草研究所渕ission specialists害羞草研究所� aboard. However, 翱肠别补苍骋补迟别害羞草研究所檚 website suggests that the fifth person aboard may be a so-called 害羞草研究所渃ontent expert害羞草研究所� who guides the paying customers.

OceanGate said its focus was on those aboard and their families.

害羞草研究所淲e are deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to reestablish contact with the submersible,害羞草研究所� it said in a statement.

Authorities have yet to formally identify those on board, though some names have been confirmed.

British businessman Hamish Harding, who lives in Dubai in the United Arab Emirates, was one of the mission specialists, according to Action Aviation, a company for which Harding serves as chairman. The company害羞草研究所檚 managing director, Mark Butler, told the AP that the crew set out on Friday.

害羞草研究所淭here is still plenty of time to facilitate a rescue mission, there is equipment on board for survival in this event,害羞草研究所� Butler said. 害羞草研究所淲e害羞草研究所檙e all hoping and praying he comes back safe and sound.害羞草研究所�

Harding is a billionaire adventurer who holds three Guinness World Records, including the longest duration at full ocean depth by a crewed vessel. In March 2021, he and ocean explorer Victor Vescovo dived to the lowest depth of the Mariana Trench. In June 2022, he went into space on Blue Origin害羞草研究所檚 New Shepard rocket.

Harding was 害羞草研究所渓ooking forward to conducting research害羞草研究所� at the Titanic site, said Richard Garriott de Cayeux, the president of The Explorers Club, a group to which Harding belonged.

害羞草研究所淲e all join in the fervent hope that the submersible is located as quickly as possible,害羞草研究所� he said in a statement.

Also on board were Pakistani nationals Shahzada Dawood and his son Suleman, according to a family statement sent to the AP. The Dawoods belong to one of Pakistan害羞草研究所檚 most prominent families. Their eponymous firm invests across the country in agriculture, industries and the health sector.

害羞草研究所淲e are very grateful for the concern being shown by our colleagues and friends and would like to request everyone to pray for their safety while granting the family privacy at this time,害羞草研究所� the statement said. 害羞草研究所淭he family is well looked after and are praying to Allah for the safe return of their family members.害羞草研究所�

Shahzada Dawood also is on the board of trustees for the California-based SETI Institute that searches for extraterrestrial intelligence.

French explorer and Titanic expert Paul-Henry Nargeolet also was on board, according to David Gallo, a senior adviser for strategic initiatives and special projects at RMS Titanic. Gallo identified Nargeolet, a friend who has led multiple expeditions to the Titanic, on Tuesday during an interview with CNN.

The expedition was 翱肠别补苍骋补迟别害羞草研究所檚 third annual voyage to chronicle the deterioration of Titanic, which struck an iceberg and sank in 1912, killing all but about 700 of the roughly 2,200 passengers and crew. Since the wreckage害羞草研究所檚 discovery in 1985, it has been slowly succumbing to metal-eating bacteria. Some have predicted the ship could vanish in a matter of decades as holes yawn in the hull and sections disintegrate.

The initial group of tourists in 2021 paid $100,000 to $150,000 apiece to go on the trip. 翱肠别补苍骋补迟别害羞草研究所檚 website had described the 害羞草研究所渕ission support fee害羞草研究所� for the 2023 expedition as $250,000 a person.

Unlike submarines that leave and return to port under their own power, submersibles require a ship to launch and recover them. OceanGate hired the Polar Prince to ferry dozens of people and the submersible craft to the North Atlantic wreck site. The submersible would make multiple dives in one expedition.

The expedition was scheduled to depart from St. John害羞草研究所檚, Newfoundland, in early May and finish up at the end of June, according to documents filed by the company in April with a U.S. District Court in Virginia that oversees Titanic matters.

CBS journalist David Pogue, who went on the trip last year, noted his vessel got turned around looking for the Titanic.

害羞草研究所淭here害羞草研究所檚 no GPS underwater, so the surface ship is supposed to guide the sub to the shipwreck by sending text messages,害羞草研究所� Pogue said in a segment aired on CBS Sunday Morning. 害羞草研究所淏ut on this dive, communications somehow broke down. The sub never found the wreck.害羞草研究所�

The submersible, named Titan, is capable of diving 2.4 miles (4 kilometers) 害羞草研究所渨ith a comfortable safety margin,害羞草研究所� OceanGate said in its court filing.

It weighs 20,000 pounds (9,072 kilograms) in the air, but is ballasted to be neutrally buoyant once it reaches the seafloor, the company said.

In a May 2021 court filing, OceanGate said the Titan had an 害羞草研究所渦nparalleled safety feature害羞草研究所� that assesses the integrity of the hull throughout every dive.

During its expedition in 2022, OceanGate reported that the submersible had a battery issue on its first dive, and had to be manually attached to its lifting platform, according to a November court filing. More missions, however, followed. OceanGate has described the submersible as a 害羞草研究所渟tate-of-the-art vessel害羞草研究所� that 害羞草研究所渋s lighter, more spacious and more comfortable than any other deep-diving submersible exploring the ocean today.害羞草研究所�

But the custom-built, titanium-domed Titan represented a risk. Pogue and another passenger, a writer and producer for the cartoon series 害羞草研究所淭he Simpsons害羞草研究所� named Mike Reiss, noted how the liability waiver for the trip included stark safety warnings. also highlighted how much of the 害羞草研究所渋mprovised害羞草研究所� submersible, about the size of a minivan, operated with a single button, a video game-style controller, a makeshift toilet and material from an RV retailer.

Experts said Monday that rescuers face steep challenges.

Alistair Greig, a professor of marine engineering at University College London, said submersibles typically have a drop weight, which is 害羞草研究所渁 mass they can release in the case of an emergency to bring them up to the surface using buoyancy.害羞草研究所�

害羞草研究所淚f 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,害羞草研究所� Greig said.

Another scenario is a leak in the pressure hull, in which case the prognosis is not good, he said.

害羞草研究所淚f it has gone down to the seabed and can害羞草研究所檛 get back up under its own power, options are very limited,害羞草研究所� Greig said. 害羞草研究所淲hile 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.害羞草研究所�

Even if they could go that deep, he doubts they could attach to the hatch of 翱肠别补苍骋补迟别害羞草研究所檚 submersible.

___

Associated Press writers Danica Kirka, Jill Lawless and Sylvia Hui in London, Robert Gillies in Toronto, Olga R. Rodriguez in San Francisco, Jon Gambrell in Dubai, United Arab Emirates, and Munir Ahmed in Islamabad contributed to this report.

Ben Finley And Holly Ramer, The Associated Press

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