After four days of testimony from 10 witnesses and the presentation of numerous exhibits, the U.S. Coast Guard’s Marine Board of Investigation hearings on the Titan submersible implosion have revealed a wealth of details about the vessel’s design and operations.

However, critical questions remain unanswered, including why the submersible failed during its June 2023 expedition to the Titanic and who may be held responsible for the deaths of its five passengers. As the hearings head into their second and final week, these issues remain at the forefront.

OceanGate CEO Stockton Rush, who perished while piloting the Titan, was largely blamed during the first two days of the hearing. Tony Nissen, the former director of engineering, described Rush as someone who prioritized speed and cost, frequently changing his decisions.

Nissen also revealed that Rush fired him after he insisted on discarding the Titan’s initial carbon fiber hull due to safety concerns. David Lochridge, a former director of marine operations, testified that Rush had made piloting mistakes during a dive to the wreck of the Andrea Doria, panicked, and angrily threw the submersible’s controller at him.

Lochridge described Rush’s behavior as bullying and said he often shifted blame to others.

David Lochridge testified that several crucial parts of the Titan were assembled using components from a home improvement store, following Stockton Rush’s instructions. After Lochridge was fired for raising numerous safety concerns, he filed a whistleblower complaint with the Occupational Safety and Health Administration, but Rush retaliated by suing both him and his wife for breach of contract and fraud.

Despite the criticism, Rush had his supporters. Renata Rojas, who had participated in multiple OceanGate expeditions, described Rush as “very fair” and denied Lochridge’s account of the Andrea Doria incident.

Fred Hagen, another paying passenger, praised Rush as a brilliant individual who worked to foster a safety-conscious culture, even in a high-risk setting. “It wasn’t supposed to be safe,” Hagen told the panel. “It was meant to be a thrilling adventure.”

A Critical Analysis of the Titan Submersible Incident Tony Nissen defended his initial design of the Titan, but multiple witnesses testified that the submersible’s construction often bypassed or ignored established industry practices. OceanGate tested only one scale model of the carbon fiber hull, and despite its early failure under high pressure, the company proceeded with building a full-scale version.

Dave Dyer, an engineer at the University of Washington, testified that his lab stopped providing support to OceanGate in 2016 due to disagreements, including concerns over the use of glass control spheres, which Dyer feared could explode at great depths like a bomb. These spheres housed the control electronics for the Titan’s thrusters.

Rather than scanning the first hull for defects or setting a finite number of dives, OceanGate depended on an unproven acoustic monitoring system to detect early signs of failure. Lochridge harshly criticized the Titan, calling it “an abomination” and describing the carbon fiber hull as “disgusting.” Both he and Nissen stated they would never have dived in the vessel themselves.

A Critical Analysis of the Titan Submersible Incident  After Nissen and Lochridge’s departures, the Titan was rebuilt with a new hull that was never tested according to industry standards or certified by an independent third-party agency. Patrick Lahey, CEO of Triton Submarines, testified that certifying a new type of hull was not only feasible but crucial for safety. “We were developing and certifying the world’s deepest-diving sub at the same time they were working on this amateurish contraption,” Lahey stated, emphasizing that there was no reason OceanGate couldn’t have had the Titan certified.

A Critical Analysis of the Titan Submersible Incident  OceanGate’s initial Titanic missions in 2021 were plagued with issues, such as the Titan’s forward titanium dome detaching after a dive, concerning acoustic monitoring readings, and a thruster failure at a depth of 3,500 meters. A Coast Guard slide revealed 70 equipment problems needing correction from that season’s dives.

Though things slightly improved in 2022, with 48 recorded issues, problems persisted, including dead batteries prolonging a mission from around seven hours to 27, and the sub being damaged during recovery.

One dive in 2022 ended with a loud bang and cracking sound upon surfacing. Antonella Wilby, an engineering contractor for OceanGate, was so alarmed that she considered notifying the board of directors but was warned by a colleague that she risked being sued if she did. “Anyone should be able to speak up about safety without fear of retaliation, and that was not my experience,” Wilby testified, adding that her concerns were completely dismissed.

On the Titan’s second-to-last dive in 2023, contractor Tym Catterson admitted to skipping a safety check, which left the sub listing at a 45-degree angle for an hour, causing discomfort to those aboard.

A Critical Analysis of the Titan Submersible Incident  Testimony on the safety of the Titan’s unique carbon fiber hull was divided. Dave Dyer noted that carbon fiber could be suitable for deep-sea submersibles, while Tony Nissen firmly believed that, with proper computer modeling and the acoustic monitoring system, the hull could be used indefinitely.

However, Lochridge, Tym Catterson, and former HR director Bonnie Carl were more skeptical about the hull’s design and implementation, though they admitted they were not engineers.

Next week’s hearings, featuring Nissen’s successor, Phil Brooks, additional submersible engineers, and a carbon fiber expert from Boeing, are expected to clarify many of these concerns. Notably, testimony from an engineer at the National Transportation Safety Board’s Materials Laboratory next Wednesday may reveal the physical cause of the Titan’s implosion by examining the wreckage.

A Critical Analysis of the Titan Submersible Incident  Investigators emphasized that the Titan should have undergone inspection by the U.S. Coast Guard before carrying paying passengers. However, none of those questioned could explain why this did not occur, even though OceanGate reportedly contacted the Coast Guard several times to notify them of its underwater operations.

Lochridge testified that OSHA informed him in 2018 that it had relayed his safety concerns to the Coast Guard. One of the Coast Guard witnesses scheduled to testify next week is based in Puget Sound, near OceanGate’s headquarters, and may provide relevant insights.

Notably, U.S. Coast Guard Rear Admiral John Lockwood, who has been on OceanGate’s board since 2013, is not listed as a witness. Lochridge and Bonnie Carl indicated that Lockwood’s role was to ensure oversight and facilitate interactions with the Coast Guard.

A Critical Analysis of the Titan Submersible Incident  John Lockwood is not the only significant absence from the witness list. Multiple witnesses this week highlighted the important roles of OceanGate employees, such as Wendy Rush, Scott Griffith, and Neil McCurdy, in making critical business, regulatory, and operational decisions, including those made on the day of the accident.

None of these individuals are scheduled to testify, nor have any representatives from the hull manufacturers been called. The Coast Guard has not explained this absence, aside from denying that it is due to concerns that these witnesses might invoke their Fifth Amendment rights to avoid answering questions.