The 21-foot Titan has the capacity to stay underwater for 96 hours, according to its specifications - giving the five people aboard until Thursday morning before the air runs out. One pilot and four passengers were inside the submersible early on Sunday when it lost communication with a ship on the surface about an hour and 45 minutes into its dive.
The Titanic site is about 900 miles (1,450 km) east of Cape Cod and 400 miles (644 km) south of St. John's, Newfoundland. US and Canadian aircraft have searched more than 7,600 square miles, larger than the state of Connecticut.
Those aboard the submersible, the highlight of a tourist expedition that costs $250,000 per person, included British billionaire Hamish Harding, 58.
Shahzada Dawood, 48, the vice chair of one of Pakistan's largest conglomerates is among those missing.
He is vice chair of Engro Corporation, with investments in fertilisers, vehicle manufacturing, energy and digital technologies.
According to the website of SETI, a California-based research institute of which he is a trustee, he lives in Britain with his wife and two children.
Suleman, his 19-year-old son, is also on board the missing sub, the family has confirmed. They are both British citizens.
The 77-year-old French explorer Paul-Henri Nargeolet and Stockton Rush, founder and CEO of the vessel's US-based operating company OceanGate Expeditions, were also reported to be on board. Authorities have not confirmed the identity of any passenger.
Rescuers face significant obstacles both in finding the Titan and in saving the people aboard, according to experts.
If the submersible experienced a mid-dive emergency, the pilot would likely have released weights to float back to the surface, according to Alistair Greig, a professor of marine engineering at University College London. But absent communication, locating a van-sized submersible in the vast Atlantic could prove challenging, he said.
The submersible is sealed with bolts from the outside, which means the occupants cannot escape without assistance even if it surfaces.
If the Titan is on the ocean floor, a rescue effort would be even more challenging due to the extreme conditions more than two miles below the surface. The Titanic lies 12,500 feet (3,810 meters) underwater, where light does not penetrate. Only specialized equipment can reach those depths without getting crushed by the massive water pressure.
Ships scour North Atlantic for missing submersible near Titanic wreck
The US Department of Defense committed three C-130 planes to aid in the search and rescue operations for the missing submersible, Deputy Pentagon Spokesperson Sabrina Singh said on Tuesday.
The Canadian military has dropped sonar buoys to listen for any sounds that might be coming from the Titan, with no results thus far. A commercial vessel with an unmanned vehicle capable of deep dives is also assisting, US Coast Guard Captain Jamie Frederick told reporters at a press conference on Tuesday.
"There is a full press full-court press effort to get equipment on the scene as quickly as we can," he said.
New ships joined the search on Tuesday for a submersible vessel that went missing on a trip to explore the wreckage of the Titanic.
MarineTraffic showed seven vessels scouring the North Atlantic in the search. US and Canadian ships and planes have swarmed the area about 900 miles (1,450 km) east of Cape Cod, some dropping sonar buoys that can monitor to a depth of 13,000 feet (3,962 meters), US Coast Guard Rear Admiral John Mauger told reporters on Monday.
Canada's has also deployed its Air Force CP-140 Aurora aircraft to support efforts, and two Canadian Coast Guard ships are en route.
'Every single minute feels like hours' - a friend of missing passenger on board Titanic sub
A friend of one of the passengers on board the submersible vessel that went missing on a trip to explore the wreckage of the Titanic said that "every single minute" felt like hours as time ticked away to find them alive.
Speaking from Svalbard in Norway on Tuesday, Jannicke Mikkelsen said she was not sleeping and just hoping for good news, as rescuers scoured thousands of square miles in the remote North Atlantic to find her friend Hamish Harding, 58, and four others.
Mikkelsen said Harding was "being branded as a UK billionaire going for a sightseeing trip to the Titanic."
But, she said, expeditions were also for scientific research.
Mikkelsen said she met Harding in 2017 while working at Nasa's Kennedy Space Center. Together they took part in 2019's "One More Orbit" flight mission that set a record for the fastest circumnavigation of Earth by aircraft flying over both geographic poles.
Mikkelsen said she last spoke to Harding right before his dive to the Titanic and wished him "godspeed."
"As explorers, we are pessimistic and objective. And as it stands right now, it would be a miracle if they are recovered alive."
Titanic tourist rides are for 'wealthy risk-takers - reporter who rode on the missing sub
David Pogue, a CBS reporter and science writer, admits that he was in a panic the night before he boarded a submersible that carries wealthy adventurers to the wreck of the Titanic, which is now missing in the Atlantic Ocean with five people on board.
A video of Pogue’s trip in the fall of 2022, in which he voices his concerns about the Titan submersible’s safety to Stockton Rush, the CEO of the company that operates it, OceanGate, telling him it seems partly ‘jerry-rigged’ after finding out, amongst other things, that it is steered by an inexpensive game controller, has now gone viral.
Pogue also had to sign a waiver that noted the submersible had "not been approved or certified by any regulatory body" and could result in death.
But Pogue says that his concerns were partly allayed when Rush explained that ‘experimental, one-of-a-kind’ Titan, uses consumer parts because they are the most reliable, and that the main capsule had been designed with the help of Nasa.
Pogue said that Rush told him, of the capsule: “Everything else can fail. The lights can go out, the propellers can stop, but you will still be alive.”
It was enough to quiet Pogue’s nerves.
“Once I was in the sub with Stockton and, you know, the scientists and the crews outside doing what they had rehearsed over and over, I felt okay. I felt excited,” he told Reuters.
Pogue’s said that he enjoyed the journey, despite the fact that they did not go to the Titanic wreckage due to weather concerns.
OceanGate schedules five-week-long "missions" to the Titanic each summer, according to its website.
The Titan’s safety features are now being severely tested, as rescuers scoured thousands of square miles in the remote North Atlantic for a third day on Tuesday, racing against time to find the missing submersible.
Pogue says that while the events now taking place is “tragic”, the tours are intended for wealthy customers who are aware of and drawn to the risks involved.
“It's for really rich adventurer people who live for Blue Origin rocket rides and volcanoes and swimming with sharks. It's for people who define their lives by risk. So, it's really not meant to be a consumer tourist outfit,” he said.
Asked if he would take another trip aboard the Titan given what has taken place, Pogue says he doubts that anyone would be willing to do so.
“I think very few people would sign up for this tour again after this event, even if they are rescued. I think, unfortunately, this is probably done a death blow to Stockton's plans for this adventure company,” he said.
The sinking of the Titanic, which killed more than 1,500 people, has been immortalized in books and films, including the 1997 blockbuster movie "Titanic" which renewed popular interest in the wreck.
Reuters