What to know about the missing Titanic tourist submarine

»Update: The pilot and four passengers of a missing submersible that disappeared en route to the wreckage of the Titanic are believed to be dead, the expedition company said Thursday.

A search effort for a missing submarine carrying five people to view the Titanic wreckage is underway.

“Titan,” a 21-foot submersible — a smaller, less-powerful type of submarine that launches from a mother ship — began its annual dive taking a group of marine experts and paying tourists to the wreck site Sunday. But Titan lost contact after about an hour and 45 minutes.

Now, the search and rescue is a race against the clock, with the small vessel only carrying a few days’ worth of oxygen and fuel. The U.S. Coast Guard in Boston is leading a joint search with Canadian rescue teams.

Discourse about the missing vessel has ranged from confusion to conspiracy theories. But, Greg Williams, the Independence Seaport Museum’s Submarine Becuna manager, says submarines have gone missing and faced dangerous situations for many years.

Here’s what you need to know.

A group called OceanGate Expeditions runs the tours of the Titanic wreckage, which have been taking place annually since 2021.

The private company, based out of Everett, Wash., was formed in 2009 with a focus on increasing access to ocean exploration. It is recognized as a pioneer in deep-sea tourism. In May, the company shared the first full-sized digital scan of the wreck site.

While OceanGate’s trips to see Titanic wreckage have included archeologists and marine experts, they are also open to general clients, who can pay $250,000 to participate.

In a 2017 interview with Fast Company, CEO Stockton Rush said he wanted to use the Titanic voyages as proof of robotic technology for oil and gas companies.

According to OceanGate’s website, the company also provides equipment and staff for scientific research projects.

In response to Titan going missing, OceanGate said in a statement it is cooperating with the search and “exploring and mobilizing all options to bring the crew back safely.”

It’s unclear.

When the submersible lost communication with the control crew, the mothership — located about 400 miles south of St. John’s in Newfoundland — called in the Coast Guard.

The five passengers on Titan include clients, a diving expert, and OceanGate CEO Rush himself, multiple news outlets confirmed.

The clients do not necessarily have maritime experience but receive training according to OceanGate.

British businessman Hamish Harding said on his social media he would be joining the voyage. Harding previously went into space on Blue Origin’s New Shepard rocket.

Harding’s post added that diver PH Nargeolet was scheduled to be on the trip, too. Nargeolet is a Titanic expert who has participated every year according to OceanGate’s archived web page.

A well-known Pakistani father-son duo is also aboard, according to their family.

“As of now, contact has been lost with their submersible craft and there is limited information available,” the family of Shahzada and Suleman Dawood said in a statement shared with news outlets.

» READ MORE: A Philadelphia University graduate is among the missing Titanic submarine group

Shahzada is a graduate from Philadelphia University according to his personal biography.

Days into the search, multiple news outlets confirmed with OceanGate the CEO was aboard.

The CEO and founder is a longtime advocate for deep-sea tourism. He also shares a tie to Pennsylvania.

According to The New York Times, Rush is a descendant of two signers of the Declaration of Independence: Benjamin Rush and Richard Stockton. Benjamin Rush was also the founder of the College of Physicians here in Philadelphia.

According to the Coast Guard, the search zone covers roughly 900 miles east of Cape Cod, Mass. and stretches 13,000 feet deep. The conditions are reportedly choppy and foggy.

“It is a challenge to conduct a search in that remote area,” Coast Guard District 1 Rear Admiral John Mauger said during a news briefing. “But we are deploying all available assets to make sure that we can locate the craft and rescue the people onboard.”

The Coast Guard said it is searching on and below the surface, using sonar technology. No acoustics from the vessel have been detected.

According to OceanGate’s web archive, a Titanic dive typically takes about 10 hours.

Titan began its descent Sunday morning with about four days of emergency capability.

Authorities estimated Tuesday morning that the vessel’s supply was down to two days’ worth.

Yes. According to CBS correspondent David Pogue, when he traveled on an OceanGate Titanic expedition last summer, the ship’s control room lost contact one-way with the submersible for about three hours, citing technical difficulties.

“The difference this year is that it seems like they lost contact with the ship,” Pogue told NPR. “They can’t even reach the sub and that’s really scary.”

According to Williams of the Independence Seaport Museum, missing submarines are not new, but are somewhat rare in modern history.

The U.S. Navy’s Submarine Force has lost 65 submarines in its 123 years, the vast majority during World War II Williams said. It’s unclear how many non-U.S. military submarines have faced issues over time.

Williams said the exact cause of some sunk submarines is unknown since there were no survivors.

“Post-war submarine losses in the U.S. Navy have been significantly less,” he said.

Among the most notable post-war losses was the USS Thresher, a vessel lost in 1963 while performing deep-diving tests east of Cape Cod.

Williams said that a chain of malfunctions led Thresher to slowly sink and eventually implode. It prompted the Navy to implement a safety program that holds its submarines to rigorous standards. Since the program’s implementation, Williams said, the Navy has only lost one submarine.

But vessels like OceanGate’s Titan aren’t necessarily held to the same standards.

According to NPR, a waiver voyagers had to sign before boarding says Titan has not been approved or certified “by any regulatory body.”