The massive search for the missing submersible near the Titanic wreck has entered a critical stage amid growing concerns about oxygen levels on board.
If the submarine is still functioning and intact, it may only have low levels of oxygen left, based on previous estimates.
It went missing in a remote area of the North Atlantic on Sunday, leaving five crew members without oxygen for four days.
And even on Thursday, many questions remained about how it could be recovered.
The minivan-sized submarine, owned and operated by the private company Oceangate Expeditions, has yet to be found. If found, they must be reached by complex rescue equipment and brought to the surface in an operation likely to take hours.
That needs to happen before the oxygen supply runs out and without damaging the ship’s structure or endangering the crew.
The condition of the ship and its five crew members are unknown, but the US Coast Guard said the operation remained a rescue mission. “This is a 100% search and rescue mission,” Capt. Jamie Frederick told reporters Wednesday.
There seems to be a glimmer of hope after officials said undersea noise was detected by Canadian search planes on Tuesday and Wednesday.
However, it is still unclear what these are, and officials said they may not have come from a submarine. A remotely operated underwater search vehicle (ROV) has been deployed in the area where the sound was detected, but nothing has yet been found.
One of the ROVs deployed from the Canadian vessel Horizon Arctic reached the seafloor early Thursday morning. Several more arrived on the ground later in the day, and more multinational aid was expected to arrive.
The French research vessel Atalante also arrived in the area on Thursday morning and deployed its own ROV, the U.S. Coast Guard said. The robot can probe the depths of the Titanic wreck, which is about 12,500 feet (3,810 meters) below the surface, and has experience with the Titanic.
The total area of the ocean being scoured is approximately 26,000 square kilometers (10,000 square miles), twice the size of Connecticut in the United States. Experts say the area is prone to heavy weather and poor visibility, making search efforts more difficult.
The 21-foot-long vessel will feature British businessman Hamish Harding, British-Pakistani businessman Shazada Dawood and his son Suleman, former French Navy diver Paul-Henry Narjolet, and the submersible operator. Oceangate CEO Stockton Rush is on board.
Rear Admiral John Mauger of the US Coast Guard told the BBC: “One of the factors that make it difficult to predict oxygen reserves is that we don’t know the rate of oxygen consumption per submarine crew.” .
Dr Ken Redez, an expert in hyperbaric medicine at Memorial University in St. John’s, Newfoundland, told the BBC that depending on the crew’s physical fitness and the conditions inside the submarine, the crew may be able to survive with reduced oxygen supplies. said.
It’s impossible to know the exact situation inside, but the crew will probably face rising carbon dioxide levels and possibly coping with low temperatures in addition to lower oxygen levels, Dr. Rudez said.
The combination of these factors can cause hypothermia and unconsciousness, he said. But these symptoms aren’t necessarily fatal, he added, and the cold’s slowed metabolism may help them survive longer.
“They are very smart… very skilled people,” he said. Among them, “If someone survives”, “It is these people”.