US Coast Guard confirms when Titanic sub set to run out of oxygen as desperate search enters final hours

US Coast Guard spokesperson told The Independent they expect Titan will run out of oxygen at 1pm UK time on Thursday

The air supply on the missing Titanic tourist submarine is down to its last hours, as rescue workers continue their increasingly desperate search for the five stranded passengers.

A US Coast Guard spokesperson told The Independent they expect the vessel, named Titan, will run out of oxygen at 1pm UK time on Thursday. This estimated time is based on the number of hours of oxygen the craft had for the five people on board - 96 - and the time it submerged - 1pm UK time on Sunday.

Other deadlines have been bandied around, such as 12.08pm UK time on Thursday - but the US Coast Guard said they did not know where that time had been sourced from.

Five people are missing aboard the Atlantic Ocean vessel (Dirty Dozen Productions/OceanGate/AFP/Getty)

The spokesperson said: “Based on the approximate 96 hours of oxygen supplies on the vessel at the time of deployment, any other estimates [than 1pm UK time on Thursday] would be too uncertain for us to confirm.”

The countdown for the rescue effort is all the more urgent after Canadian aircraft searching for the submarine in a remote part of the North Atlantic Ocean detected intermittent “banging” noises from the vicinity of its last known location, the US Coast Guard said.

Crew searching for the missing sub heard banging sounds every 30 minutes on Tuesday and again four hours later on Wednesday after additional sonar devices were deployed.

However, the US Coast Guard clarified that they “don’t know the source of the noise”.

Rescue workers continue their increasingly desperate search for the five stranded passengers (Canada air force)

The massive search and rescue operation has been ongoing for over three days after the watercraft submerged on Sunday morning from its support vessel, the Polar Prince, to travel to the Titanic wreckage, which sits at a depth of 12,500ft, and lost contact about an hour and 45 minutes later. The submersible craft is equipped with a four-day emergency oxygen supply.

The US Coast Guard’s latest estimate is a slight revision after its captain Jamie Frederick said at a press conference on Tuesday that officials believed the sub had “40 to 41 hours” of oxygen left at that time, which suggested it was due to run out between 10.30am and 11.30am UK time (5.30am and 6.30am ETD).

Aboard the Titan is CEO and founder of OceanGate Expeditions Stockton Rush, British billionaire explorer Hamish Harding, renowned French diver Paul-Henri Nargeolet and Pakistani businessman Shahzada Dawood and his 19-year-old son Suleman Dawood.

Friend of Mr Harding Professor Mark Hannaford, an explorer himself and founder of World Extreme Medicine, said: “Putting yourself in their shoes is incomprehensible, especially for the families. It’s very hard to imagine people you know in that situation - and what they’re likely to be going through.

“But Hamish is so accomplished, extremely bright, a great pilot and engineer - if there’s anybody who can fix their way out of this situation, Hamish is one of them.”