(NewsNation) — The Titan submersible hearing resumed Friday with witnesses continuing to recount their experience with OceanGate as the U.S. Coast Guard investigates the submersible implosion that killed five people on a dive to the wreck of the Titanic.

The final witness of the day, Antonella Wilby, was a contractor who worked for OceanGate. She said on one dive, a passenger heard a noise “as loud as an explosion,” and she did not feel the company was taking that customer’s concerns seriously. When she took her concerns to the director of administration, Wilby said she was told there were concerns about her and that she “didn’t have an explorer mindset.”

Wilby was also asked about safety culture.

“I saw what I would classify as safety theater,” Wilby said.

She defined that as people doing things like carrying expensive safety devices but being unwilling to have basic conversations about procedures. Wilby, a remote-operated vehicle pilot, had joined OceanGate with hopes of becoming a submersible pilot but declined to go on dives after feeling that her worries about safety weren’t being taken seriously.

Mission specialist Fred Hagen was the first to testify. Other witnesses have said mission specialist was a title given to those who paid to dive with OceanGate.

Hagen suggested that anyone who thought going into depth with the Titan was safe was “delusional,” characterizing the project as experimental and adventurous.

He described several incidents that occurred during various dives he took part in. Those included a dive where the front dome sheared off when the submersible was being lifted onto the deck of a support ship and a dive where the incorrectly weighted submersible spiraled to the ocean floor, where thrusters failed to work and some weights meant to drop to allow the vessel to resurface became stuck.

“It was clear that it was dangerous,” Hagen said. “It’s kind of like jumping out of an airplane. I mean, you don’t do it because it’s safe, you do it because it’s an adrenaline rush.”

Dave Dyer, engineer with the University of Washington’s Applied Physics Laboratory, testified about testing and early development on the Titan. The group stopped working with OceanGate in 2017, years before the implosion.

Dyer said earlier plans for the submersible had been entirely made of carbon fiber, but when a smaller model of the sub was subjected to the expected pressure, it failed several times. That led to the domes being swapped out for titanium.

When asked, Dyer said he would not consider one unmanned test of a submersible sufficient to begin sending people on dives.

OceanGate and the lab parted ways due to disagreements about how the company approached engineering and testing.

Triton Submarines CEO Patrick Lahey testified regarding certification, a process that can be both time-consuming and costly. While most submersibles are certified through independent organizations, it is not a requirement to operate.

Lahey stated that he was unimpressed the times he had run into Stockton Rush and OceanGate, saying that in his view, the Titan was not quite ready for prime-time. He also expressed that he “had not and would not” dive in an unclassified vessel and said that while innovation is important he considers certification “foundational” to operate submersibles.

After viewing a prototype for Titan, Lahey said he noted issues including the use of glass spheres as junction boxes, no lift handles and generally described the work as “amateurish.”

Lahey also explained how his company has worked with certifying organizations to develop new rules or do additional testing for novel innovations on submersibles. Previous witnesses had stated that the Titan was not classified because there were no existing rules for submersibles with a carbon fiber hull.

He also brought up a letter for the Marine Technologists Society that expressed concerns that Titan was unsafe and that the mission to the Titanic could have serious consequences. When lawyers for OceanGate provided a press release that indicated the draft letter had never been formally sent, Lahey appeared genuinely shocked and confused as to why it was never delivered to OceanGate.

It was noted that while it had not been formally issued, the draft letter was shared with OceanGate and Rush.

What has been learned so far?

The Coast Guard’s investigatory panel has listened to three days of testimony that raised questions about the company’s operations before the doomed mission. The public hearing is part of a high-level investigation into the cause of the implosion.

OceanGate co-founder and CEO Stockton Rush was among five people who died when the submersible imploded en route to the site of the Titanic wreck in June 2023.

Mission specialist Renata Rojas was the latest person to testify before the investigatory panel Thursday.

Rojas refuted testimony from previous witness David Lochridge regarding the OceanGate mission to the wreck of the Andrea Doria. She said that while the submersible did crash into the side of the wreck, there was no panicking or crying from passengers as Lochridge described.

Lochridge labeled the experimental submersible unsafe before its last, fatal voyage.

During questioning about her role in various dives, Rojas described the role she and other passengers played. She also likened the project to NASA’s Apollo program of the 1960s, saying it was “testing by doing.”

In an emotional closing statement, Rojas said the loss of her friends was still very raw but “exploration takes risks” and she hopes the implosion does not dampen innovation or other projects involving citizen scientists.

On Monday, witnesses painted a picture of a troubled company that was impatient to get its unconventionally designed craft into the water. The accident sparked a worldwide debate about the future of private undersea exploration.

OceanGate said it has been fully cooperating with the Coast Guard and NTSB investigations since they began. The Titan had been making voyages to the Titanic wreckage site going back to 2021.

OceanGate Scientific Director Steven Ross also testified before the hearing wrapped Thursday. More witnesses are expected to testify with the hearing set to continue into next week.

Titan submersible implosion

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 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.

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

In addition to 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 Associated Press contributed to this report.