Rescuers are facing a race against time to find a missing submersible that was heading down to view the Titanic shipwreck, due to there being a limited oxygen supply.
British billionaire Hamish Harding is one of five people on board the submersible craft Titan, which went missing on Sunday (June 18) in the Atlantic Ocean.
A search and rescue operation was announced by the Boston Coastguard near Newfoundland not long after.
It is understood from the vessel's operator, OceanGate Expeditions, Titan has a 96-hour oxygen supply in case of emergencies - meaning only around two days of "life support" remain, Sky News reports.
French submersible pilot, Paul-Henry Nargeolet, and chief executive and founder of OceanGate Expeditions, Stockton Rush, are also understood to have been on board.
— OceanGate Expeditions (@OceanGateExped) June 19, 2023
OceanGate said in a statement that it was "exploring and mobilising all options" to bring the crew back safely.
Rescuers facing potential big problem
The Titanic wreck can be found 12,500ft below the ocean surface, whilst the submersible can dive to 13,120ft "with a comfortable safety margin".
The vessel operates by pinging back a message every 15 minutes to signal to those ashore that it is safe, but Sky News reports these have stopped.
Marine operations specialist Mike Welham outlined the difficulties in the search operation, adding that "very specialised underwater vehicles" would be needed to go to the depths of the Titanic wreck.
The Titanic was 882 feet and 9 inches long when it set sail, and it was the largest manmade moveable object of its time more than 110 years ago.
— OceanGate Expeditions (@OceanGateExped) May 30, 2023
Today's largest cruise ship, the Wonder of the Seas, comes in at just under 1,200 feet. #TitanicTuesday pic.twitter.com/PMa6Sxn8er
Mr Welham told Sky News: "The biggest problem they've got is the depth of water at the Titanic site.
"It's about 3,800m and you need very specialised underwater vehicles to go down to that depth and they're not really readily available. So they have a major problem if they have to search and recover this vehicle."
The submersible was taking part in OceanGate's third annual voyage to monitor the decay of the ship's wreckage, following expeditions in 2021 and 2022.
A major search and rescue operation is taking place, led by the US Coast Guard and involving military aircraft 900 miles east of Cape Cod.
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