What To Know About Tourist Sub That Disappeared On An Expedition To the Titanic Wreck

A massive search ramped up as authorities probed the North Atlantic for a tourist submarine.

A massive search ramped up as authorities probed the North Atlantic for a tourist submarine that went missing over the weekend on an expedition to explore the famous Titanic shipwreck. Here's what we know so far about the submersible craft and what may have happened to it.

What happened?

A five-person crew on a submersible named Titan, owned by OceanGate Expeditions, submerged on a dive to the Titanic wreckage site Sunday morning, and the crew of the Polar Prince research ship lost contact with the sub about an hour and 45 minutes later, the U.S. Coast Guard said Monday afternoon.

The sub was lost in an area about 900 miles east of Cape Cod, in the North Atlantic, in water with a depth of about 13,000 feet. It had less than 40 hours of breathable air left as of Tuesday evening. 

"We will do everything in our power to effect a rescue ... There is a full-court press effort to get equipment on scene as quickly as we can," Coast Guard Capt. Jamie Frederick told reporters during a news conference Tuesday afternoon, calling the search effort "an incredibly complex operation."

By Tuesday, crews from the U.S. Coast Guard, Canadian coast guard, U.S. Navy and Air National Guard had collectively searched about 7,600 square miles since the sub vanished two days prior, according to Frederick. That combined search area is larger than the state of Connecticut, the captain noted.

A Coast Guard official said earlier that the people aboard included an operator and four mission specialists — a term the company uses for its passengers. CBS News confirmed that Hamish Harding, a British billionaire and adventure traveler, is among the group of those missing.

Search and rescue is underway

News of the vanished submersible and subsequent search broke Monday morning. At the time, Lt. Jordan Hart of the Coast Guard in Boston told CBS News that personnel there were leading the rescue mission, and focusing on waters off Newfoundland in eastern Canada. Hart said Coast Guard personnel were "currently undergoing a search and rescue operation" in that area in an effort to locate and recover the submarine.

The Boston Regional Coordination Center was managing the rescue operation, a spokesperson for the Canadian coast guard confirmed. The location of the Titanic shipwreck falls within the Boston coordination center's territory, according to a map of jurisdictions along the East Coast of North America.

Search operations continued overnight Monday and into Tuesday, when a pipe-laying vessel arrived in the search area and sent a remotely operated vehicle into the water to search for the sub at its last known location, Frederick said. Coast Guard officials also said Tuesday that aircraft would fly over the search area throughout the day, and multiple Canadian vessels, including a Canadian coast guard vessel expected to arrive in the evening, as well as a U.S. Coast Guard cutter were on their way in the early afternoon. The U.S. Navy was preparing to deploy military assets to assist in the search as well.

Officials previously said crews would expand their search Tuesday to include deeper waters.

Just after midnight EDT on Wednesday, the U.S. Coast Guard said a Canadian aircraft had detected underwater noises in the search area and underwater search operations were relocated as a result, though the origin of the noises remained unknown.

"As we continue on with this search ... we've been working through the night with a broad group of partners to bring all capabilities to bear looking on both the surface and now expanding to a subsurface in the area," U.S. Coast Guard Rear Admiral John Mauger told CNN.

Earlier, the U.S. Coast Guard said it had a C-130 aircraft searching for the sub, and that the Rescue Coordination Center Halifax is assisting with a P8 Poseidon aircraft, which has underwater detection capabilities.

"We are doing everything that we can to make sure that we can locate and rescue those on board," Mauger said during a Monday afternoon briefing.

"It is a remote area and it is a challenge to conduct a search in that remote area, but we are deploying all available assets to make sure that we can locate the craft and rescue the people on board," Mauger said. 

Sonar buoys have been deployed in the water in an attempt to listen for the missing sub. They're capable of listening to a depth of 13,000 feet.

The Coast Guard is focused on finding the sub right now, but they're also working with military partners and civilians to develop a rescue plan if the vessel is located underwater, Mauger said. 

"Right now we're focused on locating the vessel. But at the same time, if we find this vessel in the water then we will have to effect some sort of rescue," Mauger said. "We're coordinating, reaching out to different partners within the U.S. Navy, within the Canadian armed forces, and within private industry to understand what underwater rescue capability might be available."

The missing submarine

The unique submersible craft that disappeared is owned by OceanGate Expeditions, a company that deploys manned submarines for deep sea exploration and has in the past advertised this particular sub's endeavor to carry tourists down to the wreckage of the RMS Titanic for $250,000 per seat. 

More than a century after the Titanic sunk in April 1912, the wreck lies on the ocean floor about 400 miles southeast of the Newfoundland coast. 

OceanGate said recently on its website and on social media that its expedition to the shipwreck was "underway," describing the seven-night trip as a "chance to step outside of everyday life and discover something truly extraordinary." In addition to one ongoing expedition, the company had planned two others for the summer of next year, according to the site.

In a statement, OceanGate confirmed the missing submarine is theirs and that a rescue operation had been launched to find and recover it. The company said it was "exploring and mobilizing all options to bring the crew back safely." The company did not specify how many people were inside the sub.

"For some time, we have been unable to establish communications with one of our submersible exploration vehicles which is currently visiting the wreck site of the Titanic," said Andrew Von Kerens, a spokesperson for OceanGate. "We pray for the safe return of the crew and passengers, and we will provide updates as they are available."

The sub has emergency oxygen and a 96-hour sustainment capability if there's an emergency aboard, Mauger said. As of Monday afternoon, he said there was believed to be "somewhere between 70 to the full 96 hours available at this point."

Who is Hamish Harding?

Hamish Harding, a 59-year-old British billionaire, businessperson and explorer, was aboard the submarine when it disappeared, CBS News has confirmed. As BBC News previously reported, Harding announced publicly his decision to join the Titanic shipwreck expedition.

Harding's company, Action Aviation, later confirmed that he was aboard, The Associated Press reported. "There is still plenty of time to facilitate a rescue mission, there is equipment on board for survival in this event," the company's managing director, Mark Butler, told the AP. "We're all hoping and praying he comes back safe and sound."

Government officials in the United Kingdom told CBS News they are in contact with Harding's family and prepared to assist as search and rescue operations continue. 

"The FCDO [Foreign, Commonwealth and Development Office] are in contact with Hamish Harding's family and the local authorities," an official spokesperson for the Prime Minister's office said in a statement. "We stand ready to provide any additional assistance, including as our capacity as the host nation for Nato's multinational submarine rescue capacity."

In a post shared to his Facebook page on Saturday, Harding wrote: "I am proud to finally announce that I joined OceanGate Expeditions for their RMS TITANIC Mission as a mission specialist on the sub going down to the Titanic."

"Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023," Harding's Facebook post continued. "A weather window has just opened up and we are going to attempt a dive tomorrow. We started steaming from St. Johns, Newfoundland, Canada yesterday and are planning to start dive operations around 4am tomorrow morning. Until then we have a lot of preparations and briefings to do."

That post was Harding's most recent social media update related to the submarine trip. It included multiple photographs of him, including one that showed Harding signing his name on a banner that read "Titanic Expedition Mission V" and another that pictured the submersible vessel itself.

Richard Garriott de Cayeux, president of The Explorers Club, where Harding helped found the board of trustees, said they spoke last week about the expedition in a letter to club members after the sub's disappearance. 

"When I saw Hamish last week at the Global Exploration Summit, his excitement about this expedition was palpable. I know he was looking forward to conducting research at the site," the letter said. 

Harding is a veteran adventure tourist who traveled to space aboard a Blue Origin rocket last year.

Who are the other passengers?

The Coast Guard has not publicly identified any of the individuals on the missing sub as of Tuesday afternoon, but CBS News confirmed that in addition to Harding, British-Pakistani businessman Shahzada Dawood, his son, Suleman, French explorer Paul-Henri Nargeolet, and Stockton Rush, the CEO of OceanGate Expeditions, were on the vessel.

The Dawood family, of the large Pakistan-based global business conglomerate Dawood Group, issued a statement Tuesday confirming their family members were on the expedition.

"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 statement said. Shahzada Dawood is vice chairman of the Dawood Hercules Corporation, part of the Dawood Group, which the Seti Institute, a nonprofit research organization based in California, said "has been a family business for over a century." Dawood sits on the board of trustees at the Seti Institute, according to its website.

British Foreign Secretary James Cleverly acknowledged the sub's disappearance at a news conference Tuesday morning, saying, "The U.K. government's thoughts are with those individuals that are currently in the submersible in the north Atlantic. We wish them all the luck and we hope they will be swiftly found and returned to their loved ones."

Nargeolet, a renowned French explorer and former diver for the French Navy, who was part of the first expedition to visit the Titanic wreck in 1987, was returning on another dive aboard the now-missing submersible. 

Rory Golden, an explorer who became the first Irish diver to visit the Titanic wreckage in 2000, shared a post on Facebook Monday about the missing submersible.

"I'm OK. We are all focussed on board here for our friends," Golden wrote. "We have a situation that is now the part of a major Search and Rescue effort, being undertaken by major agencies. That is where our focus is right now."

He added: "The reaction and offers of help globally is truly astonishing, and only goes to show the real goodness in people at a time like this." 

"Focus is on the crewmembers"

"Our entire focus is on the crewmembers in the submersible and their families," OceanGate said in its statement Monday, adding that it was "deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to reestablish contact with the submersible." 

Exactly when the vessel last made contact has not been made public either, although the Coast Guard first alerted mariners about the missing sub Sunday night, saying a "21 foot submarine" with a white hull was overdue and giving its last known position. "VESSELS IN VICINITY REQUESTED TO KEEP A SHARP LOOKOUT, ASSIST IF POSSIBLE," the alert message read.

The Coast Guard said in an update Monday that a crew was "searching for an overdue Canadian research submarine" in waters roughly 900 miles from the coast of Cape Cod in Massachusetts. 

OceanGate said in a tweet shared earlier this month that it was using the satellite company Starlink to maintain communication with the submersible craft as it journeyed toward the Titanic wreckage.

"Despite being in the middle of the North Atlantic, we have the internet connection we need to make our Titanic dive operations a success — thank you Starlink," OceanGate wrote in the tweet, which it posted alongside an image of the submersible attached to a deck on the surface of the ocean. 

The company last tweeted about its Titanic expedition on June 15.

The Titan

Dubbed the Titan, OceanGate's deep sea vessel is said to be the only five-person submersible in the world with capabilities to reach its depth at nearly 2 and a half miles beneath the ocean's surface, CBS Sunday Mornings correspondent David Pogue reported last year. 

It is one of three submersible crafts owned by OceanGate that appear on the company's website, BBC News reported, adding that the vessel typically carries a pilot, three paying guests and another person described as a "content expert" by the company. OceanGate's site says the Titan, weighing around 23,000 pounds, has the ability to reach depths of up to 4,000 meters — over 13,000 feet — and has about 96 hours of life support for a crew of five people.

Last summer, Pogue accompanied the Titan crew on the journey from Newfoundland to the site where the Titanic as lost. Several dive attempts had to be canceled when weather conditions indicated it may not be safe. At the time, he described the Titan as a one-of-a-kind submersible craft made from thick carbon fiber and coated on both ends by a dome of titanium. 

Ahead of the planned dive, Pogue recalled signing paperwork that read, in part, "This experimental vessel has not been approved or certified by any regulatory body, and could result in physical injury, emotional trauma, or death." 

Space inside the submarine was similar to the interior of a minivan, and, with just one button and a video game controller used to steer it, the vessel "seemed improvised, with off-the-shelf components," Pogue said.

On his voyage, the sub was lost for a few hours, Pogue said.

"There's no GPS underwater, so the surface ship is supposed to guide the sub to the shipwreck by sending text messages," he reported at the time. "But on this dive, communications somehow broke down."

What could've happened inside

Butch Hendrick, president and founder of Lifeguard Systems — a company that conducts dive training for public safety officers — told CBS News Tuesday that it's possible the Titan had reached the ocean floor when it lost communication. Hendrick speculated the Titan "could have gotten itself entangled somewhere," which could have caused the "communication antenna" to become "dislodged" and "broken," prompting the vessel to lose communication.

Hendrick also explained that it was more likely that the Titan would have "leaked and flooded" rather than imploded. He said that, at the depth of the Titanic's wreckage, the pressure is about 5,000 pounds per square inch (PSI) greater than the pressure at sea level.

"There's no opening a gate, there's no opening a window, there's no making an interactive lock," Hendrick said, adding that a possible leak could potentially impact the submersible's electrical system.

"If that happened, then it may be again that they could still be alive, interior, breathing, and hoping for someone to come and get them," Hendrick said.

Were conditions right for the dive?

G. Michael Harris, founder of RMS Titanic, Inc. — a company that salvages artifacts from the Titanic wreckage — told CBS News on Tuesday evening that Titanic expeditions are generally conducted within a "three-month weather window" between the end of June and September, when the ocean waters are at their calmest.

Harris, who has led several expeditions to the wreckage site, questioned why the Titan's dive was conducted as early as Sunday.

"Right now, it's really early in the season, I'm not sure why OceanGate went out this soon," Harris said.

Harris also noted that when he conducts diving expeditions, he uses a transponder system, something that he believed the Titan likely did not have.

"It's a net that we navigate in so that we know where we are at all times on the wreck of the Titanic," Harris said. "We're in constant communication with the vessel up top."

Harris said the Titan was "put on a sled and dumped in the water and their only navigation is from the support ship up top."

"I don't adhere to that myself, personally," Harris said. 

Harris noted that he has worked with Nargeolet, who is listed as director of underwater research for RMS Titanic, for the past 30 years, describing him as an "all-around good guy."

This story was originally published by CBS News on June 21, 2023 at 2:46 a.m. ET. 

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