Details about the passengers on board have emerged as as search and rescue teams frantically search thousands of square miles of the ocean
Rescue teams are continuing the search for a submersible tourist vessel which went missing during a voyage to the Titanic shipwreck with three Britons among the five people aboard.
The submersible was taking part in its third annual voyage by OceanGate Expeditions to monitor the decay of the ship’s wreckage, following previous trips in 2021 and 2022, when those above ground lost contact with the crew.
The vessel, named Titan, has up to 96 hours of oxygen on board as teams frantically search the ocean 900 miles east of Cape Cod.
Who are the five people currently missing on the submersible?
British billionaire Hamish Harding, has been described by fellow explorer Colonel Terry Virts as "the quintessential British explorer".
He is the chairman of Dubai-based private plane firm Action Aviation, which confirmed on Monday he is one of the mission specialists on the five-person OceanGate Expeditions vessel.
Mr Harding, 58, holds three Guinness World Records, including the longest duration at full ocean depth by a crewed vessel when in March 2021, he and ocean explorer Victor Vescovo dived to the lowest depth of the Mariana Trench.
On July 9-11 2019, Mr Harding was mission director and crew pilot for the flight mission One More Orbit, which set the current world speed record for the fastest circumnavigation of earth by aircraft over both geographic poles.
In June 2022, he went into space on Blue Origin’s New Shepard rocket.
On social media at the weekend, he said he was "proud to finally announce" he would be aboard the mission to the wreck of the Titanic, the luxury ocean liner which hit an iceberg and sank in 1912, killing more than 1,500 people.
"He's very positive, very funny, a people person," said Colonel Virts, who flew on One More Orbit with Mr Harding.
"I imagine if it was 100 years ago he would be leading a British expedition to the south pole and if it was several hundred years ago he would have been sailing the ocean trying to find new lands."
Shahzada Dawood and Sulaiman Dawood
Reportedly among the wealthiest people in Pakistan, Shahzada Dawood, 48, is a UK-based board member of the Prince's Trust charity.
He studied law at the University of Birmingham in 1998, and now serves as vice-president for the Engro Corporation, which makes fertilisers, food, and energy, and of which is 79-year-old father Hussain is chairman.
Mr Dawood is in the submersible with his 19-year-old son, Sulaiman Dawood.
The pair's family released a statement on Tuesday: "As of now, contact has been lost with their submersible craft and there is limited information available.
"We are very grateful for the concern being shown by our colleagues and friends and would like to request everyone to pray for their safety while granting the family privacy at this time.
"The family is well looked after and are praying to Allah for the safe return of their family members."
As CEO and founder of OceanGate Inc, a company that provides crewed submersible services to enable researchers and explorers to access the oceans' vast resources, Stockton Rush insisted only last year the mission was safe.
After training as a pilot, he became the youngest jet transport rated pilot in the world at the age of 19.
He obtained his BSE in Aerospace Engineering from Princeton University in 1984, and his MBA from the UC Berkeley Haas School of Business in 1989.
The same year, Mr Rush personally built a Glasair III experimental aircraft, which he still owns and flies.
He also completed a heavily modified Kittredge K-350 two-man submersible, in which he has conducted over 30 dives to date.
Mr Rush is a founder and member of the board of trustees of non-profit organisation OceanGate Foundation, which aims to "catalyze emerging marine technology to further discoveries in marine science, history, and archaeology".
In an interview with CBS News last year, he said about the Titanic mission: "What I worry about most are things that will stop me from being able to get to the surface.
"Overhangs, fish nets, entanglement hazards.
"And, that's just a technique, piloting technique.
"It's pretty clear - if it's an overhang, don't go under it.
"If there is a net, don’t go near it. So, you can avoid those if you are just slow and steady.'
Paul-Henri Nargeolet served in the French Navy for 25 years, and is now known as "Titanic's greatest explorer".
According to his biography on the website of the Experiential Media Group, Mr Nargeolet is "widely considered the leading authority" on the Titanic shipwreck.
OceanGate's website describes him as a "renowned Titanic expert, having led six expeditions to the Titanic wreck site and lectured at numerous Titanic exhibitions around the world".
Mr Nargeolet has been Director of the Underwater Research Program for Premier Exhibitions, RMS Titanic, for over 16 years.
In that time, according to the EM Group, Mr Nargeolet has completed 35 dives in the Titanic submersible and "supervised the recovery of 5,000 artifacts".
He is a former commander, sub pilot, ship captain, clearance diver and deep diver for the Marine Nationale, the French Navy.
Mr Nargeolet has previously spoken frankly of the dangers of deep-sea exploration: "If you are 11m or 11km down, if something bad happens, the result is the same," he said.
"When you're in very deep water, you're dead before you realise that something is happening, so it's just not a problem."
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