Oxygen running out: Sounds heard earlier may not be from missing Titanic sub, says US commander

Former US Navy nuclear submarine commander David Marquet has warned that the sounds heard in the recent few hours, which signalled hope for many that the missing Titanic expedition submersible could be found, may not have come from the vessel.

He told the BBC that it "could just be natural sounds", and that the odds of survival are low.

Race against time

The race to find the submersible, that disappeared on its way to the Titanic wreckage site, entered a new phase of desperation on Thursday morning as the final hours of oxygen possibly left on board the tiny vessel ticked off the clock.

Rescuers have rushed more ships and vessels to the site of the disappearance, hoping underwater sounds they detected for a second straight day might help narrow their search in the urgent, international mission. But the crew had only a four-day oxygen supply when the vessel, called the Titan, set off around 6am Sunday, which runs out at around 2pm UAE time on Thursday.

Even those who expressed optimism warned that many obstacles 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.

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