Search Continues for 'Titan' Sub, Which Is Likely Out of Air — But Some Believe There’s Still Time

OceanGate co-founder Guillermo Söhnlein “firmly” believes that the window of time to rescue the missing passengers “is longer than what most people think"

The search continues for a missing submersible that was traveling to the site of the Titanic wreckage — but crews may be out of time.

Five people were onboard the Titan, a 21-foot submersible owned by OceanGate Expeditions, when it lost contact with Canadian research vessel Polar Prince on Sunday. Among those on board is OceanGate CEO Stockton Rush.

The sub started with about 96 hours of oxygen when it entered the water, according to United States Coast Guard Captain Jamie Frederick, who spoke at a press conference in Boston on Tuesday.

Just before 12 p.m. ET on Thursday, the Coast Guard announced that a remotely-operated vehicle (ROV) had discovered “a debris field” within the search area near the site of the Titanic.

Estimates suggest that the Titan ran out of breathable air this morning, but some individuals are holding on to hope for the missing passengers.

Related: Everything to Know About the 'Titanic'-Bound Sub That Has Gone Missing

Guillermo Söhnlein, who co-founded OceanGate with Rush in 2009, said in a statement Thursday that he “firmly” believes that the window of time to rescue the missing passengers “is longer than what most people think.

“I'm certain that Stockton and the rest of the crew realized days ago that the best thing they can do to ensure their rescue is to extend the limits of those supplies by relaxing as much as possible,” added Söhnlein.

During an appearance Thursday on Today, United States Coast Guard Rear Admiral John Mauger confirmed that crews are still hoping to rescue the victims.

“We continue to find, and particularly in complex cases, that people’s will to live really needs to be accounted for,” said Mauger, who is leading the search for the missing sub.

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Multiple agencies from numerous countries have been assisting in the search for the missing vessel, which went missing about 900 miles east of Cape Cod and 400 miles south of St. Johns, Newfoundland, according to authorities.

On Thursday morning, the U.S. Coast Guard’s Northeast Division said a Canadian vessel named Horizon Arctic has deployed a remotely-operated vehicle (ROV) “that has reached the sea floor and began its search for the missing sub.”

French vessel named L'Atalante also “deployed their ROV” Thursday morning, per the Coast Guard.

However, the vessel may not be underwater any longer. Aaron Newman, an OceanGate investor, told CNN that the vessel “is designed to come back up” to the surface automatically after 24 hours in the water.

Lines securing a ballast to the vessel are designed to come apart after 24 hours lapse, Newman told the outlet. Crew members can also release the heavy weights, which are used to help keep the vessel stable, by rocking back-and-forth or by using what’s called a “pneumatic pump.”

Related: Who Is on the Missing 'Titanic'-Bound Sub? All About the Passengers

Söhnlein is among those hoping for the best. He told CNN two pilots were rescued from a downed submersible in 1972 despite having “only 72 hours of life support.”

That said, Thursday “will be a critical day in this search and rescue mission,” as the Titan's life support supplies start to “run low,” he added.

“I would encourage everyone to remain hopeful for getting the crew back safely,” Söhnlein wrote in Thursday’s statement. “I continue to hold out hope for my friend and the rest of the crew."

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