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(MANEND NEWS): Air to a missing submersible with five people on board was expected to last just a few more hours if that on Thursday (today), the fifth day of a desperate multinational search in the vast Atlantic waters around the wreck of the Titanic.
The minivan-sized Titan, operated by US-based OceanGate Expeditions, began its descent at 1200 GMT on Sunday but lost contact with its support ship near the end of what should have been a two-hour dive to the century-old shipwreck.
Having set off with 96 hours of air, according to the company, its oxygen tanks would likely be depleted some time on Thursday. Precisely when depends on factors such as whether the craft still has power and how calm those on board are, experts say, and assumes the Titan is still intact.
Engro Corp Vice Chairman Shahzada Dawood, his 19-year-old son Suleman, British billionaire Hamish Harding, French explorer Paul-Henri Nargeolet, OceanGate CEO Stockton Rush were on board the craft.
Rescue teams and relatives and friends of the Titan’s five occupants took hope when the US Coast Guard said on Wednesday that Canadian search planes had recorded undersea noises using sonar buoys earlier that day and on Tuesday.
But the Coast Guard said remote-controlled underwater search vehicles directed to where the noises were detected had not yielded results and officials said the sounds might not have originated from the Titan.
“When you’re in the middle of a search-and-rescue case, you always have hope,” Coast Guard Captain Jamie Frederick said on Wednesday, adding analysis of the noises was inconclusive.
Organisers of the multinational response — which includes US and Canadian military planes, coast guard ships and teleguided robots — are focusing their efforts in the North Atlantic close to multiple “underwater noises” detected by sonar.
The French research ship Atalante, equipped with a robotic diving craft capable of reaching depths even below the Titanic wreck which lies about 12,500 feet below the surface, was moving into the area.
The French robot, called Victor 6,000, has arms that can be remotely controlled to help free a trapped craft or hook it to a ship to haul it up. The US Navy is sending a special salvage system designed to lift large undersea objects.
‘Underwater noises being analysed’
Ships and planes have scoured 10,000 square miles (around 20,000 square kilometers) of surface water — roughly the size of Massachusetts — for the vessel, which was attempting to dive about 400 miles off the coast of Newfoundland, Canada.
After the noises were detected by a Canadian P-3 aircraft, rescuers relocated two remotely operated vehicles (ROV) that search under the water and one surface vessel with sonar capability.
The ROV searches have not yielded results but data from the Canadian aircraft has been shared with US Navy experts for acoustics analysis.
“There have been multiple reports of noises and every one of those noises is being analysed,” said Carl Hartsfield, from the Woods Hole Oceanographic Institution.
He added that the sounds “have been described as banging noises”.
Frederick said the number of surface vessels in the search would double from five to 10 within 24 to 48 hours.
The Navy has sent a specialised winch system for lifting heavy objects from extreme depths, other equipment and personnel; and the Pentagon has deployed three C-130 aircraft and three C-17s.“
But even if the Titan were located, retrieving it would present huge logistical challenges.
If the submersible had managed to return to the surface, spotting it would be difficult in the open sea and it is bolted shut from the outside, so those inside cannot exit without help.
If Titan is on the ocean floor, a rescue would have to contend with the immense pressures and total darkness at that depth. Titanic expert Tim Maltin said it would be “almost impossible to effect a sub-to-sub rescue” on the seabed.
“The Titanic wreck is broken into two parts and there is a cloud of debris around and in between them – finding a submersible among that is not simple,” said Jean Jarry, an engineer who worked for French research institute Ifremer.
Fears of a leak
Titan’s mission was expected to be the only manned trip to the Titanic this year due to bad weather, Harding wrote in on Instagram beforehand.
The Titanic hit an iceberg and sank in 1912 during its maiden voyage from England to New York with 2,224 passengers and crew on board. More than 1,500 people died.
It was found in 1985 and remains a lure for nautical experts and underwater tourists.
The pressure at that depth as measured in atmospheres is 400 times what it is at sea level.
Mike Reiss, an American television writer who visited the Titanic wreck on the same sub last year, told the BBC the experience was disorientating.
Alistair Greig, professor of marine engineering at University College London, has suggested two possible scenarios based on images of the Titan.
He said if it had an electrical or communications problem, it could have surfaced and remained floating, “waiting to be found” — bearing in mind the vessel can reportedly be unlocked from the outside only.
“Another scenario is the pressure hull was compromised — a leak,” he said in a statement.
“Then the prognosis is not good.”
Sean Leet, who heads a company that jointly owns the support ship, the Polar Prince, said on Wednesday all protocols were followed but declined to explain how communication ceased.
“There’s still life support available on the submersible, and we’ll continue to hold out hope until the very end,” said Leet, chief executive of Miawpukek Horizon Maritime Services.
Questions about Titan’s safety were raised in 2018 during a symposium of submersible industry experts and in a lawsuit filed by OceanGate’s former head of marine operations, which was settled later that year.
