There was a a slight shudder in the Titan submersible prior to its implosion deep in the waters of the Atlantic Ocean, killing five people, a hearing into the tragedy has been told on its last day.
The submersible's crew lost contact with its support vessel on June 18 last year about 2 hours after making its final dive.
The vessel had imploded, killing its five-member crew — OceanGate co-founder Stockton Rush, French diver Paul-Henri Nargeolet, British billionaire Hamish Harding, Pakistani businessman Shahzada Dawood and his 19-year-old son, Suleiman.
OceanGate owned the Titan and took it on several dives to the Titanic going back to 2021.
A Coast Guard panel that is investigating the Titan disaster has heard two weeks of testimony that ended on Friday local time.
Here are the key takeaways from the hearings:
Co-founder spoke of buying off a congressman
The final day of hearings brought some dramatic moments, including when a former OceanGate employee testified that company co-founder Stockton Rush brushed aside worries about the US Coast Guard.
Mr Rush reportedly said that "if the Coast Guard became a problem, then he would buy himself a congressman and make it go away," according to Matthew McCoy, who resigned after the interaction.
Stockton Rush (right) alongside fellow founder Guillermo Sohnlein. (ABC News/Reuters: Shannon Stapleton)
Friday's hearing also heard that the captain of Titan's support vessel felt, in hindsight, there was a slight shudder around the time the submersible imploded on its way to the wreckage of the Titanic last year.
Captain Jamie Frederick, commander of the Boston Coast Guard sector, said it was "unconscionable that they wouldn't share that" in real time, and said it could have "changed the equation" in terms of the Coast Guard rescue response.
NASA, Boeing describe limited roles in sub's creation
NASA and Boeing officials on Thursday described what they called their limited roles in the creation of the doomed submersible Titan.
This is despite the OceanGate co-founder previously touting ties to NASA and aerospace manufacturers.
Debris from the Titan submersible was recovered from the ocean floor near the wreck of the Titanic days after the implosion in June 2023. (AP: Paul Daly/The Canadian Press)
Justin Jackson, a materials engineer, said NASA was unable to fulfil a role in building and testing the carbon fibre hull because of the COVID-19 pandemic.
He said NASA officials were uncomfortable with being linked to the experimental submersible, saying "our folks had some heartburn" when OceanGate suggested NASA's endorsement.
Boeing was involved in an early feasibility study of the use of carbon fibre for Titan's hull and in OceanGate's acoustic sensors on the hull before the relationship ended.
Mark Negley, material and process engineer at Boeing, said OceanGate ultimately departed from some of its recommendations on the pressure hull.
The Titan vessel could dive to a depth of 4,000 metres. (Associated Press/ABC News)
Clients referred to as 'explorers', not passengers
Amber Bay, director of administration for OceanGate, pushed back at a question focusing on whether OceanGate felt a sense of "desperation" to complete the dives because of the high price tag.
Ms Bay insisted on Tuesday that the company would not "conduct dives that would be risky just to meet a need."
That said, she told the Coast Guard panel: "There definitely was an urgency to deliver on what we had offered and a dedication and perseverance towards that goal."
She also referred to clients as "mission specialists" and "explorers," not passengers.
Amber Bay, director of administration for OceanGate, speaks at the Titan sub hearing. (AP: Corey Connor/Pool)
She noted that she knew all of them.
"There's not a day that passes that I don't think of them, their families and the loss," she testified through tears.
Co-founder hopeful for a renewed interest in exploration
OceanGate co-founder Guillermo Sohnlein said he hoped the tragedy would yield a renewed interest in exploration.
"This can't be the end of deep ocean exploration," Mr Sohnlein said on Monday.
He said the company was started with a laudable goal: "We wanted to give humanity greater access to the ocean, specifically the deep ocean."
Guillermo Sohnlein told the hearing he hoped the disaster did not lead to the end of "deep-sea exploration".
Expert says carbon fibre is susceptible to fatigue failure
Roy Thomas of the American Bureau of Shipping testified about challenges associated with carbon fibre, which was used for the pressure hull of the sub.
He noted that carbon fibre was difficult to manufacture and salt water could damage and weaken the material in multiple ways.
Mr Thomas said there was no recognised standard for a submersible carbon fibre pressure hull for human occupancy and that carbon fibre was "susceptible to fatigue failure under repeated external pressurisation".
Members of the investigative board stand for a moment of silence at the conclusion of the hearings. (AP: Mic Smith)
The lead engineer said he wouldn't get in the Titan
When testifying about a dive that took place several years before the fatal accident, lead engineer Tony Nissen said he felt pressured to get the Titan ready and he refused to pilot it.
"I'm not getting in it," Mr Nissen said he told Mr Rush.
Mr Nissen said Mr Rush was difficult to work for, made demands that often changed day-to-day, and was focused on costs and schedules.
Mr Nissen said he tried to keep his clashes with Mr Rush hidden so others in the company wouldn't be aware of the friction.
Sub malfunctioned a few days before its fatal dive
Scientific director Steven Ross said that on a dive just a few days before the Titan imploded, the vessel had a problem with its ballast, which keeps vessels stable.
The issue caused passengers to "tumble about" and crash into the bulkhead, he said.
"One passenger was hanging upside down. The other two managed to wedge themselves into the bow," Mr Ross testified.
He said nobody was injured but it took an hour to get the vessel out of the water.
Mr Ross added he did not know if a safety assessment or hull inspection was carried out after the incident.
Steven Ross, former OceanGate scientific director, speaks via video link at the hearing. (AP: Corey Connor)
It wasn't the first time the Titan had problems
A paid passenger on a 2021 mission to the Titanic said the journey was aborted when the vessel started experiencing mechanical problems.
"We realised that all it could do was spin around in circles, making right turns," Fred Hagen said.
"At this juncture, we obviously weren't going to be able to navigate to the Titanic."
He said the Titan resurfaced and the mission was scrapped.
Mission specialist Fred Hagan said it was "never supposed to be safe" diving in the Titan. (AP: Corey Connor)
Mr Hagen said he was aware of the risks involved in the dive.
"Anyone that wanted to go was either delusional if they didn't think that it was dangerous, or they were embracing the risk," he said.
One employee said authorities ignored his concerns
Operations director David Lochridge said the tragedy could possibly have been prevented if a federal agency had investigated the concerns he raised with them on multiple occasions.
Mr Lochridge said that eight months after he filed a complaint with the Occupational Safety and Health Administration, a caseworker told him the agency had not begun investigating.
David Lochridge had complained to federal authorities about OceanGate. (AP: Andrew J. Whitaker/The Post/ Pool)
By that time, OceanGate was suing Mr Lochridge and he had filed a countersuit.
A couple of months later, Mr Lochridge said, he decided to walk away from the complaint.
He said the case was closed and both lawsuits were dropped.
"The whole idea behind the company was to make money," he told the hearing.
"There was very little in the way of science."
After Mr Lochridge's testimony, the federal agency responded that, at the time, it had "promptly referred" his safety concerns to the Coast Guard.
AP