The deep-sea exploration community was shocked and saddened by the Titan disaster on June 18, which killed its five passengers.
It was the first time in nearly a hundred years that anyone had died during a dive. Now, federal investigators are trying to figure out what went wrong with the submersible. Some engineers who spoke to The New York Times have pointed out some possible flaws in the submersible’s design.
OceanGate’s Titan, was different from most submersibles. It had a pill-shaped hull that could fit more people inside. Most submersibles have a spherical hull, which is better at handling the huge pressures of the deep sea.
The ill-fated submersible also used a cheaper material for its hull: carbon fiber. Most submersibles use titanium, which is more expensive but also stronger.
Titan had a carbon fiber cylinder in the middle, and titanium hemispheres on the ends. This meant that there were joints between two different materials, which can be tricky to seal properly.
These design choices may have made Titan more vulnerable to failure. A tubular hull shape is not as good as a spherical one at resisting the pressure that builds up as you go deeper into the ocean. A bigger hull also needs to be stronger and thicker than a smaller one to survive the same pressure.
Titan’s hull was mostly made of carbon fiber, unlike Alvin, a research submersible that has been diving safely over 4,500 times since 1973.
Alvin has an all-titanium hull. Carbon fiber is strong and light, but it is better at resisting forces that pull it apart than forces that squeeze it together.
Under the extreme pressure of a deep-sea dive, carbon fiber may crumple or crack.
Another major drawback is that carbon fiber and titanium behave differently when they are compressed or expanded. This can affect how well they stick together at the joints. Other factors, like water, salt, and how tight the hatch bolts are, can also weaken the hull structure.
OceanGate did a lot of work and testing for Titan, but they did not get any certification from any of the organizations that specialize in making sure deep-diving crafts are safe. OceanGate’s CEO, Stockton Rush, said that certification would hold back innovation, but experts say that testing and certification are very important for safety.
The materials used for the hull should be tested for how they handle stress and damage over time. The submersible should be tested under the same conditions and pressures that it will face in the ocean. Testing can help find and fix any problems or weaknesses.
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OceanGate wanted to make deep-sea exploration better by breaking some of the usual rules. That can be a good thing, but safety should always come first.
Experts say that testing and certification should be given a lot of attention to make sure that a submersible is reliable and safe.
Kedar Kirane, a mechanical engineer with expertise in damage and fracture, said that if he had designed the Titan, he would be more focused on testing and certification.
“I would probably emphasize the actual testing itself because that’s very critical. Safety is at stake, so before actually using it in a real-world application, I would make sure it passes all the certification and a lot of experiments.”
Investigators are still looking into what caused Titan to implode.