WASHINGTON — The crew of the Titan's support ship felt a "shudder" around the time they lost contact with the submersible during its doomed dive to the Titanic shipwreck, the Coast Guard said Friday.

U.S. Coast Guard Marine Board of Investigation Chair Jason Neubauer revealed during the last day of a two-week hearing on the implosion that the master of the Polar Prince told them that in hindsight, he believes he felt the ship "shudder" around the time when communications with the sub were lost during the June 2023 expedition.

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 OceanGate 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 Friday 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."

“My initial reaction is, if that was information they have, to me personally, it would be unconscionable that they would not share that with the unified command," Frederick said.

Neubauer added that from the crew's perspective, the shudder was "not immediately connected to the event" so wasn't reported to the Coast Guard.

Frederick detailed during his testimony the complex, international search and rescue response, which culminated with a remotely operated vehicle able to go to a depth of 6,000 meters finding the Titan debris on June 22 on the ocean floor.

"They discovered the tail cone first. And then as we continued to find additional debris, it became apparent that it had been a total loss," he said.

The implosion killed all five passengers, including Stockton Rush, the co-founder and CEO of the sub's maker, OceanGate. French explorer Paul Henri Nargeolet, British businessman Hamish Harding, Pakistani businessman Shahzada Dawood and his 19-year-old son, Suleman, were also killed.

Frederick said the responders understood the Titan had survival systems on board and that they "never even got to the point to have the discussion of suspension."

"I wouldn't even want to speculate on when that would happen," he added.

Frederick also addressed knocking noises detected by sonar buoys in the vicinity of the search location the day after the Titan imploded. He said the data was given to the U.S. Navy, which determined two days later it was not anyone knocking on the hull of the Titan. "They were 100% certain that it was not human in nature," he said.

He also addressed an "anomaly" consistent with an implosion that was detected by the U.S. Navy in the general vicinity of where the Titan was at the time communications were lost. He said he was informed of the data a day after the Titan was lost and the information was classified at the time.

"It was one piece of data. It wasn't definitive," he said. "The Navy couldn't tell us that it was 100% definitive, that it was an implosion."

Rush said he would 'buy a congressman' to make Titan problems go away: Ex-employee

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

Matthew McCoy was an active duty member of the U.S. Coast Guard prior to joining OceanGate as an operations technician in April 2017 as the company was building the first Titan prototype, which was never used on Titanic dives. He said he quit six months later, in September 2017, a day after his conversation with Rush.

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 Rush responded that the Titan would be operating in the Bahamas and launch out of Canada and would not fall under U.S. jurisdiction.

"I think I had expressed to him that still taking U.S. passengers on there for hire at any point in time, if they touched the U.S. land, you know, U.S. port, that would also be of consideration," McCoy said.

He said the conversation became "tense" and ended with Rush saying that "if the Coast Guard became a problem, 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. And basically, after that, I resigned. I couldn't work there anymore."

Asked by the Marine Board of Investigation if he felt like Rush was trying to intimidate him or if it was "more like bluster," McCoy said he felt like Rush was trying to "either intimidate me or impress me."

McCoy, a member of the Coast Guard Reserve, said he wasn't clear on the regulations for the sub but was concerned about potentially violating U.S. law. He said he considered whether to notify the Coast Guard but OceanGate hadn't done any dives in the U.S. with Titan.

He said he subsequently learned of a complaint OceanGate whistleblower David Lochridge filed in 2018 with the Occupational Safety and Health Administration following his termination. McCoy said he thought there would be a "deeper investigation" into OceanGate at that point. Lochridge's 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.

McCoy said there was an "alarm bell" before he quit that made him concerned about OceanGate's operations and the production of the Titan's carbon-fiber hull.

When he started, he said, it was "made very clear" OceanGate was working with the University of Washington's Applied Physics Laboratory and Boeing, "so they had a lot of what sounded like legitimacy behind them, as far as the engineering."

But he said he soon learned the company had broken ties with the laboratory and Boeing wasn't going to be doing the layup for the carbon fiber. He said he felt OceanGate's engineering department "didn't seem overly qualified" and there were mostly "college interns" during the summer he was there.

He said after he left OceanGate he didn't keep tabs on the company for long.

"I just kind of quit following the company, not thinking that they would ever actually dive the Titan," he said.

Coast Guard investigation continues into 'unprecedented' incident

OceanGate suspended all exploration and commercial operations after the deadly implosion.

The main purpose of the hearing was to uncover the facts related to the implosion and to make recommendations, the Coast Guard said.

At the conclusion of the two-week hearing Friday afternoon, Neubauer said the Coast Guard will conduct an analysis of the evidence collected and issue any recommendations to the commandant of the Coast Guard "to help ensure that nobody has to endure a future similar occurrence."

Neubauer said that process can take several months but his priority is to "get this investigation done expeditiously, because I feel there are global issues at stake."

Any determination on potential criminal acts will also be sent to the commandant of the Coast Guard, who would decide whether to make a referral to the Department of Justice, Neubauer said.

The National Transportation Safety Board will issue a separate report on its findings, including their official determination of the probable cause of the incident, at a later date, Marcel Muise, an investigator with the agency's Office of Marine Safety, said at the conclusion of the hearing.

Neubauer offered his condolences to the families of those killed and thanked the more than two dozen witnesses who testified in the proceedings.

"It takes courage to testify in the public spotlight, especially in the aftermath of a traumatic event," he said. "The subject matter covered during the sessions was often highly technical and emotionally charged, and I'm grateful to each witness who stopped and assisted in our efforts to fully understand this unprecedented incident."

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