Public mobilization: The US armed forces, backed by Canada and France, hope to rescue an American, a Frenchman, a Briton and two Pakistanis by Thursday as passengers from a tourist submersible descend 4,000 meters to visit the Titanic. North Atlantic.

Two sonars detected repeating “sounds”.

According to the magazine Rollingstone, a Canadian P8 aircraft “heard shots in this area every 30 minutes. Four hours later, additional sonar was deployed and the knocking was still heard. CNN reported, citing an internal US government document, without specifying when the noise was detected.

The US Coast Guard confirms an “underwater noise” has been detected.

It is not yet known if this could be a signal from the submariners.

At noon on Tuesday, the US Coast Guard warned at a press conference in Boston (Northeast) that the small submarine had “about 40 hours of breathing air” left and that the search launched on Sunday was “particularly complex” and so far had “no conclusion”.

The Titan, which is designed to carry five people into the abyss, is about 6.5 meters long and began its descent off the northeastern US coast on Sunday, losing contact with the craft less than two hours after it landed.

Among those on board is a wealthy British businessman, 58-year-old Hamish Harding, who announced on Instagram that he would be taking part in this extreme, extraordinary scientific excursion steeped in history.

A $250,000 dive

The sinking of the Titanic in 1912 was one of the greatest shipping disasters of the 20th century.^e century

Hamish Harding is also known to have been a space tourist on billionaire and Amazon founder Jeff Bezos’ Blue Origin spacecraft.

An ardent follower of the exploits, former diver and former French naval officer Paul-Henri Narjolet, 77, an expert on the Titanic wreck, is also on the trip, according to his family.

The $250,000 dive involved Pakistani tycoon Shahjata Dawood, 48 and vice-chairman of conglomerate Engro, along with his 19-year-old son Suleiman, according to the wealthy family.

OceanGate Expeditions, the expedition’s organizer and its American boss Stockton Rush, who is also on board, pledged to “mobilize all options to bring the crew to safety.”

France is sending a boat and a robot

The Titan, designed to carry five people into the abyss, began its descent on Sunday at a length of about 6.50 meters and lost contact with the craft less than two hours after it took off, officials said.

The United States Coast Guard, a branch of the armed forces, initially dispatched two C-130 aircraft to a search area “about 1,450 km east of Cape Cod” (the northeast coast of the United States). A third C-130 and three C-17 transport planes will be deployed Tuesday evening, the Pentagon said.

The Canadian Coast Guard mobilized an aircraft and a ship, while France announced that its Institute for Research in Maritime Exploitation (IFRAMER) would send a boat and its robot.

White House National Security Council spokesman John Kirby said President Joe Biden said the Coast Guard would continue to conduct searches and that the Navy could be mobilized if necessary.

A poorly designed porthole?

As these efforts gather pace, an old complaint from 2018 has surfaced, seen by AFP, which shows that former OceanGate Expeditions executive David Lockridge was fired after raising serious doubts about the submarine’s safety.

According to the former Director of Marine Operations, a porthole at the front of a submarine is designed to withstand the pressure felt at a depth of 1,300m, and not 4,000m.

The company “refused to pay the producer to build a porthole to comply with the required depth of 4,000m,” he said.

American screenwriter Mike Reiss, producer of the acclaimed series The Simpsons“I’ve already been three times with OceanGate Expeditions, once in 2022 on the same submarine that went missing,” he told the BBC on Monday.

A totally confusing experience because “you always lose communication and find yourself at the mercy of the elements and that kind of stuff”.

Two possible theories

Without studying the craft, Alastair Craig, professor of marine engineering at University College London, raised two possible theories based on images of the device published by the press.

If there had been a problem with electricity or communications, he reckons, he could have been brought to the surface in a buoy “waiting to be found”. “Another scenario is that the hull is damaged, so the prognosis is not good,” he said, adding that “very few ships can go to” the depth it could have sunk.

The Titanic, the world’s largest liner at the time of its launch, left Southampton on April 10, 1912, bound for New York, and sank five days later after hitting an iceberg. Of the 2,224 passengers and crew, nearly 1,500 died.

The wreck was discovered in 1985, 650 kilometers off the Canadian coast in international waters of the Atlantic Ocean. Since then, the legend has been maintained by treasure hunters and tourists.