Who are the five passengers on board the missing Titan submersible?

The Titan submersible set off with 96 hours of air, according to the company, which would mean the oxygen could run out by today morning.

But experts say the air supply depends on a range of factors, including whether the submersible still has power and how calm the people aboard have remained.

The 22-foot submersible, operated by US-based OceanGate Expeditions, began its descent at 8 am on Sunday. It lost contact with its surface support ship near the end of what should have been a two-hour dive to the Titanic.

Those aboard the submersible which costs $250,000 per person, included British billionaire and adventurer Hamish Harding, Pakistani-born businessman Shahzada Dawood, 48, and his 19-year-old son Suleman, who are both British citizens.

French oceanographer and leading Titanic expert Paul-Henri Nargeolet, 77, and Stockton Rush, founder and chief executive of OceanGate, were also reported to be on board.

A Canadian aircraft searching for the sub in the Atlantic Ocean detected intermittent “banging” noises from the vicinity of its last known location, the US Coast Guard said.

Crew searching for the missing sub heard banging sounds every 30 minutes on Tuesday and again four hours later on Wednesday after additional sonar devices were deployed. However, the source of the sound has been found yet.

The Titan, built and operated by an undersea adventure tourism company called OceanGate Expeditions, remained missing as of Wednesday evening.

The vessel set off for its excursion to the Titanic’s underwater grave 13,000 feet below the water’s surface on Sunday morning. It lost contact with its mother ship, the Polar Prince, after one hour and 45 minutes.

Although we still don’t know what might have happened to the sub, experts have cohered around three basic scenarios, none of which are good news for the crew – or their families.

Catastrophic implosion
Arguably the worse-case scenario is a catastrophic rupture in the submersible’s outer shell, causing an implosion that would kill everyone aboard very quickly.

Trapped underwater
There are many reasons for that, ranging from a somehow non-catastrophic leak to getting stuck on a piece of the Titanic wreckage, which is strewn about a wide area of the ocean floor.

OceanGate, whose submersible vessel Titan carrying five crew members is lost in the North Atlantic, has offered tours to the famous shipwreck site since 2021. Bevan Hurley writes.

The search for a submarine carrying five people that went missing on its way to view the wreckage of the Titanic continues, with a growing number of ships and aircraft joining the US-Canadian rescue effort.

More than 10,000 square miles of the North Atlantic have been searched so far, according to the US Coast Guard, with reports that regular “tapping sounds” were picked up by sonar on Tuesday, providing fresh hope that the occupants are alive and Titan might yet be found.

Five additional rescue vessels will arrive in the next 24-48 hours, after the estimated time when the Titan’s oxygen reserves will have been exhausted.

However, the French ship Atalante carrying the Victor 6,000 underwater (ROV) and winch — the only one capable of reaching the Titanic wreck 4,000m under the ocean surface — was only expected to reach the search site last night.

The US Coast Guard says that mystery sounds and banging noises have been heard from the search area for the Titanic submersible Titan for a second day.

Officials said that the noises, picked up by a Canadian military P3 plane above the search site, are “inconclusive” and are still being analysed by Navy experts.

“With respect to the noises specifically, we don’t know what they are, to be frank with you,” Captain Jamie Frederick of the First Coast Guard District told reporters.

Billionaire Hamish Harding is chairman of private plane firm Action Aviation, which said he is one of the mission specialists on the five-person OceanGate Expeditions vessel reported overdue on Sunday evening about 435 miles south of St John’s, Newfoundland.

French diver Paul-Henri Nargeolet is also on the submarine, CBC News was told by Titanic expert Larry Daley. Mr Nargeolet spent 25 years in the French navy and worked with Mr Daley, who is a St John’s-based diver, on his first Titanic dive 20 years ago.

Shahzada Dawood and his son Sulaiman

Pakistani businessman Shahzada Dawood and his son Sulaiman Dawood have been named as two of the other people on the submersible in a family statement.

A statement from the Dawood Family said: “As of now, contact has been lost with their submersible craft and there is limited information available.”

OceanGate Expeditions CEO Stockton Rush is among those onboard, the company confirmed yesterday. His company, which provides crewed submersible services for researchers and explorers to travel deep into the ocean, operates the submersible that has gone missing, the Titan.

US Coast officials racing against time to find the missing Titanic expedition submersible said on Wednesday that rescuers spotted mystery objects on the ocean’s surface.

During a press briefing on Wednesday evening, Captain Jamie Frederick with the US Coast Guard revealed that helicopters flying over the ocean southwest of Newfoundland have spotted objects floating on the surface.

Mr Frederick emphasised that efforts are still very much focused on a search and rescue mission and that his team has not found any evidence that the submersible imploded. Instead, he noted, the objects spotted by search crews were most likely not linked to the submersible.

“In search and rescue missions, when aircraft are flying continuously … there is stuff out in the ocean floating,” Mr Frederick said. “We went back, we looked at it. We didn’t determine it to be debris, it didn’t correlate with the case … it is not uncommon during an active search.”

Andrea Blanco and Bevan Hurley report:

A 61-year-old retired businessman from Germany, who was one of the first people to undertake the journey to the depths of the ocean in Titan submersible two years, has described the dive as a “kamikaze operation”.

“You have to be a little bit crazy to do this sort of thing,” Arthur Loibl told the Associated Press.

After OceanGate announced its own operation, he jumped at the chance, paying $110,000 for a dive in 2019 that fell through when the first submersible didn’t survive testing.

Two years later he went on a voyage that was successful, along with OceanGate chief executive Stockton Rush, French diver and Titanic expert Paul-Henri Nargeolet, and two men from England.

“Imagine a metal tube a few meters long with a sheet of metal for a floor. You can’t stand. You can’t kneel. Everyone is sitting close to or on top of each other,” Mr Loibl said. “You can’t be claustrophobic.

”During the 2.5-hour descent and ascent, the lights were turned off to conserve energy, he said, with the only illumination coming from a fluorescent glow stick.

The dive was repeatedly delayed to fix a problem with the battery and the balancing weights. In total, the voyage took 10.5 hours.

“I was a bit naive, looking back now,” he said, adding: “It was a kamikaze operation.”