On June 18th, 2023, a submersible by the name of Titan, operated by the expedition company Ocean Gate, imploded at a depth of around 12,500 feet underwater off the coast of Newfoundland, Canada, while attempting to explore the wreck of the Titanic. On board were five passengers, including the CEO of Ocean Gate. After the incident, investigations have shown there were significant problems within the Titan’s fundamental design that could have directly led to the deaths of the passengers. In this article, I will be looking at the Titan incident and talking about the engineering failures by Ocean Gate that led to such an accident.
Material Failures
The most significant concern that was brought up was the use of experimental and untested materials within the Titan. The Titan, previously known as the Cyclops II, was built with carbon fiber rather than the traditionally used titanium. Carbon fiber is most commonly used in aerospace crafts, where the pressure exerted onto the craft is of tension rather than compression. This choice was made originally to save weight and costs, as a titanium hull would have required a significantly more expensive foam to keep buoyant. However, carbon fiber is still a relatively new material and has not been tested well enough to be used in any formal capacity, and its properties when under repeated stresses (which submersibles come under constantly when diving and resurfacing) are not well known. The submersible likely experienced delamination during its previous dives, which occurs when one layer of the composite peels off due to the structure deforming under pressure. Under such immense pressure, the delamination would have caused larger cracks, which could have led to the catastrophic failure of the structure.
The next concern lies at the end caps of the submarine. The Titan was built in a pill shape, with the aforementioned carbon fiber making up the center cylinder, while the end caps were made of Titanium. Titanium behaves differently from carbon fiber when under load. This difference can lead to increased stress at the connecting areas, which when under repeated loads, causes material fatigue and eventually potential snapping over time. Usually, these parts are constantly fatigue tested until their breaking point, such that if the parts fail, we know beforehand and understand the limits. However, Ocean Gate did not do any of this, instead only doing one test before the official dives.
Another untested part of the submarine was the acrylic glass viewport on the end of the submersible, installed on one of the Titanium end pieces. It was built out of seven inches of acrylic and was rated for only 1300 meters, while the Titanic sat at a depth of around three times that. Although Ocean Gate claimed that the acrylic was improved from when this rating was given, a lawyer stated that Ocean Gate “refused to pay for the manufacturer to build a viewport that would meet the required depth."
These aren't the only parts that were of concern either. In a 2018 report by a former employee of Ocean Gate, he stated that there were critical problems with the submersible's design and machining process. In an interview with him, he stated that "Glue was coming away from the seams of ballast bags, and mounting bolts threatened to rupture them; both sealing faces had errant plunge holes and O-ring grooves that deviated from standard design parameters. The exostructure and electrical pods used different metals, which could result in galvanic corrosion when exposed to seawater.”
The thruster cables posed “snagging hazards”; the iridium satellite beacon, to transmit the submersible’s position after surfacing, was attached with zip ties. The flooring was highly flammable; the interior vinyl wrapping emitted “highly toxic gasses upon ignition.”
All of these problems could have been solved or prevented by using correct methods or techniques. If the carbon fiber was cured using an autoclave to remove small voids between the epoxy (used to secure the different fibers), the strength of the carbon fiber would have increased tenfold. Furthermore, the use of syntactic foam and Titanium instead of carbon fiber would have removed this problem completely. There was an attempt by Ocean Gate to create an acoustic warning system to identify when the carbon fiber would have cracked and in turn when to resurface. However, such a system would have been close to useless when the cracks usually only preceded complete structural collapse by a few hundred milliseconds. As one source puts it, this warning system is like "setting up a camera to warn you when thunder is coming".
All of this could be attributed to an attempt at a money grab, with tickets for this trip being 250,000 USD each, but considering that the CEO himself went down with each group on their expeditions, Hanlon’s Razor comes to mind.
"Never attribute to malice that which can be adequately explained by stupidity."
Works Cited
Engineering.com. (2024). Was the OceanGate Sub Implosion an Engineering Failure? [online] Available at: https://www.engineering.com/story/was-the-oceangate-sub-implosion-an-engineering-failure [Accessed 7 Jan. 2024].
Mehdi Yari (2021). Galvanic Corrosion of Metals Connected to Carbon Fiber Reinforced Polymers. [online] Corrosionpedia. Available at: https://www.corrosionpedia.com/galvanic-corrosion-of-metals-connected-to-carbon-fiber-reinforced-polymers/2/1556 [Accessed 7 Jan. 2024].
Picchi, A. (2023). Years before Titanic sub went missing, OceanGate was warned about ‘catastrophic’ safety issues. [online] Cbsnews.com. Available at: https://www.cbsnews.com/news/missing-titanic-submarine-oceangate-safety-warnings-lawsuits/ [Accessed 7 Jan. 2024].
Taub, B. (2023). The Titan Submersible Implosion Was ‘an Accident Waiting to Happen’. [online] The New Yorker. Available at: https://www.newyorker.com/news/a-reporter-at-large/the-titan-submersible-was-an-accident-waiting-to-happen [Accessed 7 Jan. 2024].
The Feed (2023). The Titan: Specifications, Capabilities, Cost, Safety; all about the submersible that vanished during a di. [online] The Economic Times. Available at: https://economictimes.indiatimes.com/news/international/us/the-titan-specifications-capabilities-cost-safety-all-about-the-submersible-that-vanished-during-a-dive-to-titanic-shipwreck/articleshow/101155511.cms?from=mdr [Accessed 7 Jan. 2024]