(NewsNation) — It has been one year since the Titan submersible vanished on its voyage to the historic wreckage site of the Titanic.

The Titan, owned by OceanGate, made its last dive June 18, 2023. The craft lost contact with its support vessel an hour and 45 minutes into the dive. Five people were on board, diving 12,000 feet below the surface of the Atlantic Ocean.

The loss of communication launched a four-day search for the vessel, which ended when evidence of an implosion was found on the ocean floor. Officials concluded that the craft had been destroyed and all five people on board were killed.

Few vessels dive that deep into the ocean, and engineers and experts in the field noted previous problems with the Titan as well as warnings that the submersible was unsafe.

The search-and-recovery mission is estimated to have cost up to $1.6 million.

The U.S. Coast Guard quickly convened a high-level investigation into what happened. Concerns leading up to the investigation included the Titan’s unconventional design and its creator’s decision to forgo standard independent checks.

Investigation taking longer than expected

The investigation into the Titan implosion originally had a 12-month timeline but has been extended multiple times.

Coast Guard officials said in a statement last week that they would not be ready to release the results of their investigation by the anniversary. A public hearing to discuss the findings won’t happen for at least two more months, they said.

Investigators “are working closely with our domestic and international partners to ensure a comprehensive understanding of the incident,” Marine Board of Investigation Chair Jason Neubauer said, describing the inquiry as a “complex and ongoing effort.”

OceanGate said in a Tuesday statement that it “has ceased all operations and is continuing to cooperate with authorities, including the U.S. Coast Guard, in their investigations.” The company also said in its statement that it expresses “our deepest condolences to their families and loved ones, as well as everyone impacted by this tragedy.”

In addition to OceanGate co-founder Stockton Rush, the implosion killed two members of a prominent Pakistani family, Shahzada Dawood and his son Suleman Dawood; British adventurer Hamish Harding; and Titanic expert Paul-Henri Nargeolet.

The Titanic expedition

In 2021, OceanGate Expeditions began what it expected to be an annual voyage to track the rate of decay of the Titanic, according to the tour group’s website.

The purpose of the Titanic expedition was to chronicle the decay of the iconic ocean liner that sunk in 1912 after hitting an iceberg, killing all but about 700 of the 2,200 passengers and crew on board. The ship’s wreckage was discovered in 1985 and has been slowly deteriorating to metal-eating bacteria.

Tickets for the five-person submersible cost $250,000 a seat, with the vessel being the only one of its size capable of reaching the Titanic wreck.

Titan submersible missteps: Report

The CEO of OceanGate overstated how far along the project was and lied about issues with the vessel’s hull, a new Wired investigation revealed.

Concerns about the Titan go back at least to 2016. That June, a test tank that evolved into the Titan imploded thousands of miles ahead of the company’s safety margin during a smaller-scale test run.

Rather than ordering new models to continue testing after the 2016 incident, OceanGate began work on its full-sized model, and the vessel first successfully ventured to the Titanic shipwreck in 2021, Wired reported.

Wired’s investigation revealed that Boeing and the University of Washington contributed early on to OceanGate’s carbon-fiber submersible project, but their work wasn’t included in the final design.

Documents, emails and interviews also pointed to a company culture that was dismissive of employees who were cautious of or questioned decisions along the way. Some were fired.

The report also accuses Rush of overstating OceanGate’s progress and lying about issues with the vessel’s hull.

According to Wired, the hull was warping under compression about 37% more than it should. When an engineer voiced concerns, however, OceanGate’s director of engineering suggested in an email that the employee simply didn’t “have the stomach for this type of engineering,” reporters found.

Deep-sea exploration won’t stop

The Georgia-based company that owns the salvage rights to the Titanic plans to visit the sunken ocean liner in July using remotely operated vehicles, and a real estate billionaire from Ohio has said he plans a voyage to the shipwreck in a two-person submersible in 2026.

Several deep-sea explorers told The Associated Press that the Titan disaster shook the worldwide community of explorers, but it remains committed to continuing its missions to expand scientific understanding of the ocean.

Ohio real estate investor Larry Connor called Patrick Lahey, the co-founder and CEO of Triton Submarines, and said he wanted to build a sub that can dive to “Titanic-level depths” a few days after Titan imploded, the Wall Street Journal reported.

Lahey said Connor, who according to Forbes is worth $2 billion, aimed to “demonstrate to the world that you guys can do that.”

Now, Lahey and Connor are planning to make their journey in a two-person vessel called the Triton 4000/2 Abyssal Explorer, so named because it can dive to 4,000 meters. It is listed at $20 million on the company’s website.

The Associated Press, NewsNation’s Steph Whiteside, Caitlyn Becker and Katie Smith contributed to this report.