A LACK OF oxygen, hypothermia, and carbon dioxide poisoning are just some of the immediate challenges facing passengers of the missing Titanic sub. 

Rescue workers are racing to beat a rapidly closing oxygen window after noises detected by sonar raised hopes the five people onboard are still alive.

The submersible, named Titan, vanished on Sunday while on its way to visit the wreck of the Titanic.

All communication was lost with the 21-foot tourist craft less than two hours into its descent. 

Speaking to The Journal, Chris Reynolds, the former director of the Irish Coast Guard and the head of EU Crisis Mission to Somalia between 2019 and 2023, noted that there’s “no certainty” with the noises which have been detected. 

“So the main change today is the reports of banging or some sort of underwater noises,” said Reynolds.

“We’re not getting much detail on that, so without getting any further detail, there’s no certainty really.”

Reynolds also warned that a vessel so small is “impossible to locate”.

“You would think it would be easy to look for a submersible this size on top of the water,” said Reynolds, “but it’s near impossible if the sub doesn’t have transponders. 

“Despite all the satellite technology, no transponders mean a vessel that size would be impossible to locate.”

G. Michael Harris is the founder of RMS Titanic, Inc., a company that salvages artifacts from the Titanic wreckage, and he told CBS News that he didn’t believe the Titan sub had a transponder system. 

Reynolds added that hypothermia and carbon dioxide poisoning are among the imminent threats facing the passengers on board as a result of a lack of oxygen and battery power. 

“Without a doubt, oxygen and batteries are the greatest issue for them,” said Reynolds.

“It’s so cold at that depth, so if you lose your power, you suffer from hypothermia very quickly. 

“Following that, the air system is affected, oxygen gets lower and lower and then you’re talking about carbon dioxide poisoning. 

“Now if that’s the case, it may be some consolation to the relatives of those on board that the first symptom of CO2 poisoning is that you just fall asleep.”

The five passengers on board are are British billionaire Hamish Harding, Pakistani businessman Shahzada Dawood, his 19-year-old son Suleman, OceanGate Expeditions CEO Stockton Rush and French submarine operator Paul-Henri Nargeolet.

Nargeolet is nicknamed “Mr Titanic” for his frequent dives at the site.

Rescuers have vowed that as long as there is an opportunity for survival, every available resource will be brought to bear.

However, speaking to The Journal, Reynolds questioned the capability for a recovery. 

“At the moment, no one has indicated that the equipment is there in the area to recover this vessel if it’s located,” said Reynolds.

“They’re indicating they can search only at depth, but that doesn’t necessarily include a recovery. 

“We’ve yet to see a coastguard plan around a possible recovery. But if those in the submersible could come up from the sea bed themselves, they would have done so.”

US Coast Guard Captain Jamie Frederick told reporters yesterday that his organisation was coordinating the search.

But, he said, it was incredibly difficult, and far beyond what the coast guard would normally tackle.

“While the US Coast Guard has assumed the role of search and rescue mission coordinator, we do not have all of the necessary expertise and equipment required in a search of this nature,” he said.

“This is a complex search effort, which requires multiple agencies with subject matter expertise and specialised equipment.”

Frederick explained that rescuers were using several methods as they comb the vast area for the Titan.

“The search efforts have focused on both surface with C-130 aircraft searching by sight and with radar, and subsurface with P-3 aircraft, we’re able to drop and monitor sonar buoys.”

‘Like going into space’ 

“It’s pitch black down there. It’s freezing cold. The seabed is mud, and it’s undulating. You can’t see your hand in front of your face,” Titanic expert Tim Maltin told NBC News Now.

“It’s really a bit like being an astronaut going into space.”

OceanGate Expeditions, which runs the Titan’s trips, charges $250,000 (€228,000) for a seat.

Jules Jaffe, who was part of the team that found the Titanic in 1985, said there were two likely explanations for the sub’s disappearance.

“It’s either a mechanical failure, or an electrical failure,” he told AFP.

“I’m hoping it’s an electrical failure, because they do have weights, one of the safety procedures that they have is to make themselves lighter. So if you’re heavier than the water, you sink, if you’re lighter than the water you float.”

Jaffe, a research oceanographer at the University of San Diego, said rescuers would be looking on the surface, in the water column and on the seafloor.

“The worst place for them to be would be on the seafloor, which would imply that the vehicle itself either imploded or got tangled somehow.”

Adding to the challenge: the enormous pressure four kilometres under water, around 400 times what it is on the surface.

Such pressures put huge strains on equipment, and very few vessels can survive these depths.

Nuclear submarines generally operate at just 300 metres, according to the Woods Hole Oceanographic Institution.

Jamie Pringle, a professor of forensic geosciences at Keele University in Britain, said if the mini-sub had settled on the ocean floor, it could be very difficult to spot.

“The bottom of the ocean is not flat; there are lots of hills and canyons,” Pringle said, according to NBC.

Further complicating the seafloor prognosis is the debris field from the Titanic itself – the very thing the adventurers had gone to see.

“I mean, it’s a mangled wreck, with probably all kinds of treacherous things which would not be very friendly for a small boat,” said Jaffe.

“The opportunities for finding them in a mangled wreck within the next 36 hours, I think, are practically impossible.”

-With additional reporting from © AFP 2023