Titanic sub latest news: What we know about search for the OceanGate submersible - BBC

OceanGate

A debris field has been discovered in the search for a submersible that went missing in the North Atlantic while exploring the wreck of the Titanic.

The US Coast Guard said on Twitter that experts "are evaluating the information", and scheduled a press conference for 1500 EST (1900 GMT).

David Mearns, a dive expert and friend of the passengers, told the BBC that he had been told that the debris includes "a landing frame and a rear cover from the submersible".

The vessel went missing deep under the ocean on Sunday with five people on board.

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Researchers aboard the Polar Prince - its mothership on the surface - lost contact with the crew shortly after the Titan began its dive.

Undersea noises were earlier detected in the search area, but the US Coast Guard did not confirm they were from the sub.

On Wednesday the agency said that remotely operated vehicle operations (ROV) had been relocated "in an attempt to explore the origin of the noises", but "yielded negative results".

The five-day search has involved US, Canadian and French agencies working together to locate the submersible. Here is what we know so far.

What's the latest on the search?

The Coast Guard hasn't tweeted much in the past few days as the increasingly urgent search played out - so this latest development may prove significant.

Many experts the BBC spoke to this week worried that the Titan could have suffered a catastrophic implosion as a result of a hull failure. Such a scenario could explain the debris.

However, there is no clarity at this stage of what the new debris field is.

On Thursday morning local time, two deepwater ROVs arrived at the search site. The US Coast Guard said on social media that the submersible attached to the Canadian vessel Horizon Arctic had reached the sea floor.

The Victor 6000, which is operated from the French research vessel Atalante, was also deployed. It has a robot that can reach the seabed 3,800m (12,500ft) down, and would have the capacity to lift the Titan sub to the surface.

The vehicles designed for navy submarine rescues can't get anywhere near as deep as would be needed.

According to OceanGate, the company that owns it, Titan is one of only five manned submersibles in the world capable of reaching the depth required.

You can read more about the equipment being used in our visual guide.

Authorities said earlier the search area had been expanded to approximately twice the size of the US state of Connecticut, and a sub-surface search area of around 2.5 miles (4km) deep.

Earlier in the search, on Tuesday and Wednesday, hopes were raised when a Canadian search plane picked up underwater noises.

Deep-sea experts said it was hard to assess without seeing the data, but there was hope that they could be short, sharp, relatively high frequency noises, made at regular intervals from within the vessel by hitting a hard object against the end of the sub.

What might have happened to the sub?

Prof Alistair Greig, a submarine expert from University College London, says one of the big problems is that rescuers do not know whether to look on the surface or the seabed - it is very unlikely to be in between.

He's worked through a couple of scenarios. One is that it released a "drop weight" after an emergency, in order to bring it to the surface.

"If there was a power failure and/or communication failure, this might have happened, and the submersible would then be bobbing about on the surface waiting to be found," he said.

Another possibility is that the hull was compromised resulting in a leak. "Then the prognosis is not good," he says.

Who's on board?

Dawood family

The five people on board are:

Hamish Harding, a 58-year-old British businessman and explorer
Shahzada Dawood, 48-also a British businessman -and his son, Suleman Dawood, 19
Paul-Henry Nargeolet, a 77-year-old French explorer nicknamed "Mr Titanic"
Stockton Rush, 61, is the chief executive of OceanGate, the firm behind the dive

You can read more about them all here.

How much does a dive cost?

OceanGate Expeditions charges guests $250,000 (£195,270) for a place on its eight-day expedition to see the wreck of the Titanic.

The site is about 600km (370 miles) off the coast of Canada's Newfoundland, and lies in two parts, with the bow and the stern separated by about 800m (2,600ft). A huge debris field surrounds the broken vessel.

A full dive to the wreck, including the descent and ascent, reportedly takes eight hours and each trip is meant to include a scientific objective, including studying the wreck's decay.

The inaugural dive took place in 2021, according to the company's website.

Is it really operated by a video game controller?

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The Titan is extremely small and narrow, measuring just 670 cm x 280 cm x 250 cm (22ft x 9.2ft x 8.3ft) and can carry a crew of just five people - a pilot and four passengers, who have to sit on the floor and have limited room to move around.

Aside from taking divers to the wreck of the Titanic, it's used for site survey and inspection, research and data collection, film and media production, and deep sea testing of hardware and software.

According to the company, the Titan is "outfitted with state-of-the-art lighting and sonar navigation systems plus internally and externally mounted 4K video and photographic equipment".

The BBC's US partner CBS sent one of its reporters on a voyage with the same company last year to see the wreck of the Titanic.

Stockton Rush then gave him a tour of the submersible, where he revealed the vessel only has one button and is run using a video game controller.

It is not unusual for off-the-shelf game controllers to be used in real-life vehicles. However, the Washington Post reports that the one seen in the CBS report appeared to be an old model.

When did it go missing?

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The Polar Prince first arrived near the Titanic wreck on Sunday morning and the Titan was launched at 08:00 local time - it was expected to resurface at 15:00. Contact was lost one hour and 45 minutes into its descent, at about 09:45.

The Coast Guard said they were notified of the problem at about 17:45 - eight hours later. The agency's command centre in Boston then began coordinating search efforts.

The Titanic wreck site is approximately 600km (370 miles) off the coast of Newfoundland.

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