One year after five individuals traveling to the Titanic wreck began their dive on the Titan submersible—a vessel touted for providing an "unrivaled view of the deep ocean"—there still isn't a complete view of what went wrong.

While the U.S. Coast Guard Marine Board of Investigation (MBI) recently confirmed it "continues to actively investigate the factors that led to the tragic loss of the Titan on June 18, 2023," it admitted the process is taking "longer than initially projected to complete."

"The investigation into the implosion of the Titan submersible is a complex and ongoing effort," MBI Chair Jason Neubauer stated in a June 14 press release. "We are working closely with our domestic and international partners to ensure a comprehensive understanding of the incident." 

As for the reason for the delay, the MBI cited factors like "the need to contract two salvage missions to secure vital evidence and the extensive forensic testing required." 

And "as the one-year anniversary date approaches," the release added, "the MBI extends its deepest condolences to the families and friends of the five individuals who lost their lives during the incident."

It was June 19, 2023 when the Coast Guard announced it was searching for a 21-foot sub that had submerged the day before and lost contact about an hour and 45 minutes into the dive. The search location—approximately 900 miles east of Cape Cod—involved waters as deep as 13,000 feet.

The people on board the Titan sub were identified as adventurer and aviation mogul Hamish Harding, CEO of the OceanGate expedition company Stockton Rush, deep-sea explorer and Titanic expert Paul-Henri Nargeolet, businessman Shahzada Dawood and his 19-year-old son Suleman Dawood. After a days-long search above and below the surface and time surpassing the Titan's estimated 96-hour oxygen supply, OceanGate announced it believed the five individuals had "sadly been lost."

"These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world's oceans," the company said in a June 22 statement. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

That same day, the Coast Guard shared it found debris from the Titan.

"This morning, an ROV—a remote operated vehicle—from the vessel Horizon Arctic discovered the tail cone of the Titan submersible approximately 1,600 feet from the bow of the Titanic on the sea floor," Rear Admiral John Mauger said at the time. "The ROV subsequently found additional debris. In consultation with experts from within the unified command, the debris is consistent with the catastrophic loss of the pressure chamber."

Three days later, the Coast Guard launched a Marine Board Investigation into the loss of the sub and individuals onboard. Soon after, the Coast Guard "received debris and evidence recovered from the seafloor at the site of the Titan submersible," including what it said were "presumed human remains." (In October, the Coast Guard said "additional presumed human remains" were found and transported to U.S. medical professionals for analysis.)

In early July, OceanGate revealed it "suspended all exploration and commercial operations." One year after the incident, the company told the Associated Press it "has ceased all operations and is continuing to cooperate with authorities, including the U.S. Coast Guard, in their investigations." Representatives of the company also expressed their "deepest condolences to their families and loved ones, as well as everyone impacted by this tragedy."

One year after their deaths, reflect on the lives of those lost.

On June 18, 2023, a deep-sea submersible Titan, operated by the U.S.-based company OceanGate Expeditions and carrying five people on a voyage to the wreck of the Titanic, was declared missing. Following a five-day search, the U.S. Coast Guard announced at a June 22 press conference that the vessel suffered a "catastrophic implosion" that killed all five passengers on board.

Pakistani-born businessman Shahzada Dawood and his 19-year-old son Suleman Dawood, both British citizens, were also among the victims.

Their family is one of the wealthiest in Pakistan, with Shahzada Dawood serving as the vice chairman of Engro Corporation, per The New York Times. His son was studying at the University of Strathclyde in Glasgow, Scotland.

Shahzada's sister Azmeh Dawood told NBC News that Suleman had expressed reluctance about going on the voyage, informing a relative that he "wasn't very up for it" and felt "terrified" about the trip to explore the wreckage of the Titanic, but ultimately went to please his father, a Titanic fan, for Father's Day.

The Dawood Foundation mourned their deaths in a statement to the website, saying, "It is with profound grief that we announce the passing of Shahzada and Suleman Dawood. Our beloved sons were aboard OceanGagte's Titan submersible that perished underwater. Please continue to keep the departed souls and our family in your prayers during this difficult period of mourning."

OceanGate CEO Stockton Rush was the pilot of the Titan. The entrepreneur—who founded the research company in 2009 in Everett, Wash.—had long been interested in exploration. Rush, 61, previously said he dreamed of becoming the first person on Mars and once said that he'd "like to be remembered as an innovator."

In addition to leading voyages to see the remnants of the Titanic, Rush had another surprising connection to the historic 1912 event: His wife Wendy Rush is the great-great-granddaughter of a couple who died on the Titanic, Ida and Isidor Straus.

British billionaire Hamish Harding confirmed he was a part of the mission in a June 17 Instagram post, a day before the submersible went into the water and disappeared.

"I am proud to finally announce that I joined @oceangateexped for their RMS TITANIC Mission as a mission specialist on the sub going down to the Titanic," he wrote. "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. A weather window has just opened up and we are going to attempt a dive tomorrow."

Harding—the chairman of aircraft company Action Aviation—said the group had started steaming from St. Johns, Newfoundland, Canada and was planning to start dive operations around 4 a.m. on June 18. The 58-year-old added, "Until then we have a lot of preparations and briefings to do."

His past explorations included traveling to the deepest part of the ocean in the Mariana Trench, telling Gulf News in 2021, "It was an incredibly hostile environment. To travel to parts of the Challenger Deep where no human had ever been before was truly remarkable."

The Dubai-based businessman also circumnavigated the Earth by plane with the One More Orbit project and, last year, took a trip to space on Amazon founder Jeff Bezos' Blue Origin New Shepard rocket. Harding shared his love for adventure with his son Giles, described as a "teen explorer" on his Instagram.

As for the fifth member, a representative for French explorer Paul-Henri Nargeolet told the New York Times that he was a passenger on the Titan, with Harding also referencing him on Instagram as a member of the team. 

The Times described him as a maritime expert who was previously part of the French Navy. The 71-year-old was a bonafide Titanic specialist and has traveled to the wreckage 35 times before. Nargeolet served as the director of RMS Titanic, Inc., a company that researches, salvages and displays artifacts from the famed ship, per the outlet. 

Alongside fellow passenger Hamish Harding, he was a member of The Explorers Club, founded in 1904.

As Harding noted in his post, the submersible—named Titan—was a part of an OceanGate Expeditions tour that explores the wreckage of the RMS Titanic, which infamously sank in 1912.

The company expressed its sympathies to the families of the victims. "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. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

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