The Unconventional Design of the Titan Sub: A Recipe for Disaster?

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The Unconventional Design of the Titan Sub: A Recipe for Disaster?

The tragic implosion of the Titan submersible has raised concerns about whether its unique design and the creator’s disregard for standard safety checks in the industry ultimately led to its own demise.

According to U.S. Coast Guard Rear Adm. John Mauger, all five individuals aboard the Titan lost their lives when the sub was crushed near the iconic Titanic wreckage. The multinational search efforts came to a somber conclusion after the vessel initially lost contact with its mother ship in the unforgiving North Atlantic on Sunday.

OceanGate Expeditions, the owner and operator of the Titan, had been using the submersible to transport people to the Titanic since 2021. The sub gained attention for its unconventional features, including a carbon fiber composite hull and an elongated chamber for crew and passengers, which diverged from the more traditional spherical cabin areas and all-titanium construction.

Chris Roman, a professor at the University of Rhode Island’s Graduate School of Oceanography, who has extensive deep-sea diving experience with the Alvin submersible, explained that the spherical shape of most submersible cabins is considered ideal due to the equal distribution of water pressure on all sides. This design ensures there are no areas of higher stress or vulnerability.

In contrast, the Titan featured a larger, elongated tube-shaped chamber, making it one of the largest submersibles in operation. However, this elongation subjected the sub to increased external pressure in the midsections, resulting in higher fatigue and delamination loads, as highlighted by Jasper Graham-Jones, an associate professor of mechanical and marine engineering at the University of Plymouth.

Graham-Jones explained that fatigue is comparable to bending a wire repeatedly until it breaks, while delamination is akin to splitting wood along the grain, which is easier than chopping across it. Furthermore, the Titan’s hull had undergone numerous stress-inducing dives, resulting in the formation of tiny cracks that might have been initially undetectable but eventually led to critical and uncontrollable growth.

OceanGate promoted the Titan’s carbon fiber and titanium construction as being lighter and more efficient for deep dives compared to other submersibles. However, Graham-Jones pointed out that carbon composites have a limited lifespan when subjected to excessive loads or poor design, leading to stress concentrations. In contrast, most submersibles utilize an all-titanium construction, which is known for its durability.

Documents revealed that OceanGate had been warned about potential catastrophic safety issues arising from the experimental development of the vessel. Concerns were raised by David Lochridge, then-director of marine operations at OceanGate, in a 2018 lawsuit, stating that the testing and certification process was inadequate and posed a significant danger to passengers in an experimental submersible.

The Marine Technology Society, an organization comprising ocean engineers, technologists, policymakers, and educators, also expressed apprehension about the size of the Titan, the construction material, and the lack of third-party scrutiny for the prototype. Will Kohnen, the chairman of the organization, sent a letter to OceanGate in 2018, warning that the absence of certification could potentially lead to negative outcomes, ranging from minor incidents to catastrophic failures, impacting the entire industry.

Graham-Jones emphasized that seeking outside expertise to ensure compliance with the highest industry standards is standard practice in engineering. However, in a 2019 blog post, OceanGate criticized the third-party certification process, citing its time-consuming nature and stifling effect on innovation.

Renowned undersea explorer Robert Ballard, who first discovered the Titanic wreckage in 1985, considered the absence of external certification and classification a significant factor in the submersible’s failure, labeling it a “smoking gun.” He noted that numerous dives to similar depths had been conducted without incident, raising further questions about the Titan’s integrity.

James Cameron, director of the movie “Titanic” and an experienced deep-sea explorer, suggested that the submersible’s hull failure was the most likely cause of its destruction. However, he acknowledged that other factors might have contributed to this primary failure. Cameron cast doubt on the use of composites for vessels exposed to external pressure, supporting the theory that the composite material used in the Titan may have played a role in its demise.

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More about submersible design

• Titan Submersible Disaster Raises Questions About Design and Safety
• OceanGate Expeditions
• Marine Technology Society
• Carbon Fiber Composites in Marine Applications
• Deep-Sea Exploration and Submersibles