The latest on the Titan submersible tragedy and what’s next in the recovery efforts

FILE PHOTO: The Titan submersible, operated by OceanGate Expeditions to explore the wreckage of the sunken SS Titanic off the coast of Newfoundland, dives in an undated photograph. OceanGate Expeditions/Handout via REUTERS NO RESALES. NO ARCHIVES. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY./File Photo

The desperate search to find the missing Titan submersible turned into a recovery effort Thursday after officials announced the vessel imploded sometime this week, killing all five aboard, near the Titanic shipwreck.

Deep-sea robots will continue searching the sea floor for clues about what happened deep in the North Atlantic. The pilot and four passengers died in the catastrophic implosion.

READ MORE: How the unconventional design of the Titan sub may have destined it for disaster

The Titan, owned by undersea exploration company OceanGate Expeditions, had been chronicling the Titanic’s decay and the underwater ecosystem around the sunken ocean liner in yearly voyages since 2021.

Many questions about what occurred underwater remain: Exactly when and why did the implosion occur? Will the victims’ bodies ever be found? How could this tragedy have been prevented?

Here’s what we know so far:

When and where did the Titan go missing?

The craft submerged Sunday morning, and its support vessel lost contact with it about an hour and 45 minutes later, according to the Coast Guard.

The vessel was reported overdue about 435 miles (700 kilometers) south of St. John’s, Newfoundland, according to Canada’s Joint Rescue Coordination Centre in Halifax, Nova Scotia.

The Titan was launched from an icebreaker that was hired by OceanGate and formerly operated by the Canadian Coast Guard. The ship has ferried dozens of people and the submersible craft to the North Atlantic wreck site, where the Titan has made multiple dives.

READ MORE: Titan submersible: What is a ‘catastrophic implosion’?

What happened aboard the Titan?

The vessel suffered a catastrophic implosion, killing all five aboard, sometime this week after it submerged Sunday morning. It’s not clear exactly when or where the implosion occurred. But a senior military official said Thursday that a U.S. Navy acoustic system detected an “anomaly” Sunday that was likely the Titan’s fatal implosion.

The Coast Guard announced that debris from the submersible had been found and the end of rescue efforts Thursday, bringing a tragic close to a saga that included an urgent around-the-clock search and a worldwide vigil for the missing vessel.

READ MORE: What is the OceanGate Titan submersible and how does it work?

“The debris is consistent with the catastrophic loss of the pressure chamber,” Rear Adm. John Mauger, of the First Coast Guard District, said in a news conference Thursday.

A deep-sea robot discovered the debris, near the Titanic shipwreck, that authorities say came from the submersible.

The senior military official said the Navy went back and analyzed its acoustic data after the Titan was reported missing. That anomaly was “consistent with an implosion or explosion in the general vicinity of where the Titan submersible was operating when communications were lost,” the official said.

The official spoke on condition of anonymity to discuss a sensitive acoustic detection system.

The Navy passed on the information to the Coast Guard, which continued its search because the Navy did not consider the data to be definitive.

The Wall Street Journal on Thursday first reported the Navy’s involvement.

What’s next and who was killed?

The Coast Guard will continue searching near the Titanic for more clues about what happened to the Titan.

Officials say there is not a timeframe for when they will call off the massive international search. Mauger said that the prospect of finding or recovering remains was unknown.

READ MORE: Who died on tourist Titan submersible?

The Transportation Safety Board of Canada said Friday it’s launching an investigation involving the loss of the Titan that will focus on the cargo vessel Polar Prince.

Polar Prince is a Canadian-flagged ship that served as mothership to the Titan submersible. The Transportation Safety Board will investigate the Polar Prince in its role as a support vessel and will conduct a safety investigation into the circumstances of the operation, the agency said. It said it will coordinate with other agencies in the days ahead.

There were 17 crew members and 24 people on board the Polar Prince, the agency said.

The Titan victims are: Oceangate chief executive and Titan pilot Stockton Rush; two members of a prominent Pakistani family, Shahzada Dawood and his son Suleman Dawood; British adventurer Hamish Harding; and Titanic expert Paul-Henri Nargeolet.

“These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world’s oceans,” OceanGate said in a statement. “We grieve the loss of life and joy they brought to everyone they knew.”

Who regulates deep-sea expeditions?

The Titan’s voyage down into the North Atlantic highlights the murkily regulated waters of deep-sea exploration.

It’s a space on the high seas where laws and conventions can be sidestepped by risk-taking entrepreneurs and the wealthy tourists who help fund their dreams. At least for now.

The Titan’s fatal implosion has drawn attention to how these expeditions are regulated.

READ MORE: Past deep sea rescues show the challenges of saving those on board

The Titan operated in international waters, far from the reach of many laws of the United States or other nations. It wasn’t registered as a U.S. vessel or with international agencies that regulate safety, nor was it classified by a maritime industry group that sets standards on matters such as hull construction.

Stockton Rush, the OceanGate Expeditions CEO and Titan pilot who was among the dead, had said he didn’t want to be bogged down by such standards.

Experts say wrongful death and negligence lawsuits are likely in the Titan case — and they could be successful. But legal actions will face various challenges, including waivers signed by the Titan passengers that warned of the myriad ways they could die.

READ MORE: Submersible tragedy: ‘Profound grief’ for family of British-Pakistani father and son on Titanic sub

How much did the search cost?

The cost of the search will easily stretch into the millions of dollars for the U.S. Coast Guard alone. The Canadian Coast Guard, U.S. Navy and other agencies and private entities also rushed to provide resources and expertise.

There’s no other comparable ocean search, especially with so many countries and even commercial enterprises being involved, said Norman Polmar, a naval historian, analyst and author based in Virginia.

The aircraft, alone, are expensive to operate.

The Pentagon has put the hourly cost at tens of thousands of dollars for turboprop P-3 Orion and jet-powered P-8 Poseidon sub hunters, along with C-130 Hercules, all utilized in the search.

READ MORE: James Cameron says he wishes he’d sounded alarm over lost submersible

Some agencies can seek reimbursements. But the U.S. Coast Guard is generally prohibited by federal law from collecting reimbursement pertaining to any search or rescue service, said Stephen Koerting, a U.S. attorney in Maine who specializes in maritime law.

The first priority in search and rescue is always saving a life, and search and rescue agencies budget for such expenses, said Mikki Hastings, president and CEO of the National Association for Search and Rescue.

Rescue agencies don’t want people in distress to be thinking about the cost of a helicopter or other resources when a life is in danger.

“Every person who is missing – they deserve to be found. That’s the mission regardless of who they are,” Hastings said.