Titan implosion: Highlights from the Coast Guard's weekslong hearing

A two-week hearing into OceanGate's Titan submersible concluded on Friday, as the U.S. Coast Guard investigates the unprecedented, catastrophic implosion that killed five people while on a deep-sea voyage to the Titanic wreckage.

The Coast Guard's Marine Board of Investigation heard from more than two dozen witnesses during its hearing. They included several former employees of OceanGate, whose co-founder and CEO, Stockton Rush, was among those killed in the June 2023 implosion.

The main purpose of the hearing was to uncover the facts related to the implosion and to make recommendations to prevent similar casualties, the Coast Guard said. The National Transportation Safety Board is also investigating the implosion and will make its own determination as to the probable cause.

In addition to Rush, those killed in the implosion included French explorer and Titanic expert Paul Henri Nargeolet, British businessman Hamish Harding, Pakistani businessman Shahzada Dawood and his 19-year-old son, Suleman.

The submersible company suspended all exploration and commercial operations after the deadly implosion.

"There are no words to ease the loss endured by the families impacted by this tragic incident, but we hope that this hearing will help shed light on the cause of the tragedy and prevent anything like this from happening again," Jane Shvets with Debevoise & Plimpton, OceanGate's counsel, said during opening remarks.

Here are highlights from the hearing.

Last messages from the doomed dive

One of the last messages sent from Titan as the doomed submersible descended toward the ocean floor on June 18, 2023, was "all good here," according to an animation created by the Coast Guard that showed the text communications with the surface vessel, the Polar Prince.

The short text messages were the only means of communication between the Titan crew and the personnel on the Polar Prince as the vessel attempted to reach the Titanic, which sits 3,800 meters below sea level.

At approximately 2,274 meters, the Titan sent the message, "All good here," according to the animation.

The last communication from the submersible was sent at approximately 3,341 meters: "Dropped two wts," meaning drop weights, according to the Coast Guard.

All communications and tracking from the submersible to Polar Prince were lost at 3,346 meters, according to the Coast Guard.

Tym Catterson, a former contractor for OceanGate, testified that he believes the intention of shedding the two 35-pound weights was to slow the vessel down as it approached the ocean floor. He thought the weight was dropped a little earlier than is typical -- not due to any emergency but to ensure a smooth landing, he said.

Newly released footage of Titan

Debris from the Titan was found on the ocean floor by a remotely operated vehicle following a four-day search.

The Coast Guard released footage during the hearing that shows Titan debris, including the tail cone, aft dome, aft ring, hull remnants and carbon fiber debris, on the seafloor. The footage was from a remotely operated vehicle.

The Coast Guard also released footage of the Titan submersible's salvage captured by a remotely operated vehicle on June 26, 2023. The recovered wreckage was transported to a facility for analysis.

'Shudder' felt on Polar Prince around when Titan lost contact

Neubauer revealed during the hearing that the master of the Polar Prince said in hindsight he believes he felt the ship "shudder" around the time when communications with the sub were lost following the implosion.

The statement was provided to the board in October 2023, when the unidentified master was asked if he or crew members heard anything indicating the submersible imploded, Neubauer said.

"The answer from the master was, 'With the benefit of hindsight, I now believe I felt the Polar Prince shudder at around the time communications were reportedly lost, but at the time, we thought nothing of it. It was slight,'" Neubauer said.

Capt. Jamie Frederick with U.S. Coast Guard Sector Boston, who testified on the Titan search and rescue mission, said if that information had been reported immediately to the Coast Guard, that could have had a "drastic impact on the search efforts."

OceanGate whistleblower testifies

Several witnesses typically testified each day during the hearing, though the Coast Guard devoted one full day to the testimony of David Lochridge, the former director of marine operations for OceanGate.

Lochridge said the company only cared about making money and it wasn't interested in scientific research.

"I knew that hull would fail," he said. "It's an absolute mess."

Lochridge said he was fired days after he submitted a report in January 2018 outlining his safety concerns about the submersible's carbon-fiber hull, including imperfections, and he subsequently filed a complaint with the Occupational Safety and Health Administration. His whistleblower retaliation case was closed in late 2018 after he and OceanGate entered a settlement agreement in their respective lawsuits, OSHA said. Lochridge's safety allegations regarding the Titan were referred to the Coast Guard, OSHA said.

Paying passengers address Titan risk

Two people who paid to go on dives to the Titanic on the Titan testified that they understood the risk of going on the experimental, unclassed vessel.

Fred Hagen, a commercial building contractor and developer, said that in conversations with people such as Nargeolet, he understood the risk if something went wrong during a dive to the Titanic shipwreck.

"The conversation as related to me was that there were few assets on Earth capable of getting to depth, and that if something went wrong, that, you know, we were all going to die," he said.

"That was the paradigm that we had to be comfortable with," Hagen added.

Renata Rojas, a banker, testified that she knew the submersible was experimental but felt safe.

"For me, it was the drive of exploration," she said. "Exploration requires risks."

"Mission specialists," as the paying passengers were called by OceanGate, paid $250,000 for a seat on the Titan to see the famed Titanic shipwreck.

Rojas, who was volunteering and assisting the surface crew during the Titan's final, fatal expedition, got emotional recounting that day.

"They were just very happy to go," Rojas recalled of the passengers, crying during her testimony. "That's the memory I have. Nobody was really nervous. They were excited about what they're going to see."

Former employees say they wouldn't go on Titan

Two former OceanGate employees said they wouldn't go on the Titan due to concerns, while the company's co-founder said he never did because it didn't interest him.

Catterson testified that he would not have felt comfortable going to the depths of the Titanic wreckage in the vessel, saying he had questions about the integrity of its carbon fiber and titanium construction.

Tony Nissen, OceanGate's former engineering director, testified that Rush had asked him to be the pilot to run the Titanic missions and he turned him down.

"I told him, I'm not getting in it," Nissen said. "He asked me why, and I said, 'Because the operations crew, I don't trust them.'"

"He said, 'Well, what if I'm mission director?'" Nissen continued. "I said, 'You still have the same operations crew.' But I didn't trust Stockton either."

OceanGate co-founder Guillermo Sohnlein, who left the company in 2013, years before OceanGate began conducting dives with the Titan, said he was offered the chance to go to on the sub but never went because he wasn't interested in seeing the Titanic wreckage.

"Neither Stockton nor I were ever driven by tourism," Sohnlein said. "We were never motivated by going somewhere that people had already been before. The reason we got into this was because we both wanted to explore. We wanted to not only explore ourselves but create the technologies that would allow us to explore the ocean."

Sub experts on concerns

Several submersible experts testified about concerns they had with OceanGate and its operations.

Karl Stanley, the owner of the Honduras-based deep-sea diving expedition company Roatan Institute of Deepsea Exploration, went on one of the first crewed dives of the first prototype of the submersible in April 2019 in the Bahamas. During the dive to Titanic depth, he said the prototype carbon-fiber hull was "making noises," and the cracking sounds "amplified" the deeper they went.

Stanley said he raised his concerns about the noises in emails to Rush following the dive, writing that it seemed like there was a defect, and advised Rush to "gain more experience to mitigate risk." His emails noted that Rush told him indirectly not to speak about the noises he heard on the dive. Stanley said his emails with Rush ultimately strained their relationship.

A month after the dive, a crack was found in the carbon-fiber hull prototype, and it was not used for any Titanic dives, according to the Coast Guard.

"OceanGate came very, very close to killing me and had a severe impact on my business as well as an entire industry," Stanley said.

William Kohnen, the CEO and founder of submersible maker Hydrospace Group, discussed a draft Marine Technology Society letter he wrote in March 2018 to Rush based on public safety concerns raised during a conference.

"This was considered an issue of where we as consensus, as professionals in this industry, had significant concerns -- not on one particular thing, but the overall approach of neglecting the years of experience and tradition and diligence that we applied," he said.

The letter was ultimately never sent but Rush somehow got ahold of the draft, Kohnen said.

Triton Submarines co-founder and CEO Patrick Lahey said that when he toured OceanGate's prototype Titan sub in the Bahamas in approximately March 2019, he "wasn't particularly impressed by what I saw and I told them."

"They were very nice people, and they seemed well-intentioned. I just said it looked to me like a lot of this stuff was not quite ready for prime time," he said.

He said he believes experimental vessels should not be taking people to the deep sea.

Rush said he would 'buy a congressman': Ex-staffer

A former OceanGate employee testified that he resigned from the submersible company after Rush told him he would "buy a congressman" to make any problems with its Titan vessel go away.

Matthew McCoy was an active duty member of the U.S. Coast Guard prior to joining OceanGate in April 2017 as an operations technician as the company was building the first Titan prototype.

McCoy said he told Rush he was concerned about operating the experimental Titan vessel without a certificate of inspection and that it would not be inspected by the U.S. Coast Guard.

He said the conversation became "tense" and ended with Rush saying that "if the Coast Guard became a problem, that he would buy himself a congressman and make it go away."

"That will stand in my mind for the rest of time," McCoy said. "I've never had anybody say that to me directly, and I was aghast."

He said he quit a day after that conversation, in September 2017.

Issues and concerns with the sub

Issues and concerns with the Titan and its transport were revisited in testimony throughout the hearing.

During a 2021 dive, the forward dome detached while attempting to recover the Titan.

In 2022, the thruster controls malfunctioned and caused the vessel to spin once it reached the Titanic depth, though the pilot was able to retrain it himself and they completed the dive. In another dive that year, a loud bang was heard as the Titan ascended. Don Kramer, the acting chief of the NTSB's materials laboratory, testified that his team determined that the hull's strain response changed after this loud bang incident in subsequent dives.

In 2023, the Titan partially sank four weeks before the implosion following a night of high seas and fog, according to the Coast Guard. Days before the implosion, passengers slammed against the vessel during resurfacing when the platform malfunctioned.

One former OceanGate employee testified that there were also concerns about having to tow the sub on the open seas when they switched to using the Polar Prince in 2023.

The Titan had 70 equipment issues in 2021 that needed correcting, and 48 more in 2022, according to the Coast Guard.

Engineering firm finds implosion cause 'indeterminate'

Kemper Engineering principal engineer Bart Kemper told investigators that his firm could not determine a root cause of the implosion at this time.

"There are multiple unmitigated single-mode failures, which means that all it takes is that one thing to go for the whole thing to do," he said.

Kemper said the fact that there was an unknown design life of the sub "is a huge factor in that."

"Conceivably, the number of dives that occurred with the Titan was its actual design life," he said. "Or it might have even been less by design and exceeded it. We do not know."