An analysis of the wreckage of OceanGate’s Titan submersible has revealed how its hull came apart.
Images of the craft’s pieces scattered on the seabed show that the carbon fiber hull has separated into several layers – a known problem with the material.
The evidence was presented to the U.S. Coast Guard on Wednesday during a public hearing into the submarine’s catastrophic failure in June 2023 that killed all five people on board.
It has not been confirmed whether the hull was the first part of the submarine to give way, but details suggest it is a key element in the investigation.
Investigators are seeking to uncover details of what led to the tragedy and come up with recommendations that could prevent future deadly trips.
The Titan, operated by OceanGate, imploded less than two hours into its descent during a dive toward the wreck of the Titanic.
The Titan’s hull was made of several layers of carbon fiber mixed with resin.
It’s a very unusual material for a deep-sea submarine because it’s unreliable under pressure – most craft are made from metals like titanium.
Don Kramer, an engineer with the National Transportation Safety Board, showed the U.S. Coast Guard a series of images of sections of the hull on the seafloor.
He described how, in some fragments, the layers of carbon fibers had come apart – a process known as delamination.
In other places the material was cracked.
It has not been confirmed whether damage to the hull caused the implosion.
“I offer no analysis at this stage as to whether [the damage] “This happened before or after the implosion,” he said.
Mr Kramer also described how his team analysed samples of the Titan’s hull that were left behind after it was built. They looked at scraps of material from the submarine’s construction.
He described that the samples had areas where the carbon fiber layers had separated, as well as creases, voids and gaps.
Any irregularities in the material could have affected how the hull performed under the immense pressures exerted underwater.
The U.S. Coast Guard was also informed that a loud bang heard during a dive a year before the disaster could have damaged the submarine’s structure.
Passengers reported it as the submarine surfaced after a dive to the Titanic in 2022. One passenger described it as an “alarming audible event” in his testimony last week.
At the time, OceanGate CEO Stockton Rush said he believed it was the caisson moving within the metal frame surrounding it.
But a new analysis of sensor data by the National Transportation Safety Board suggested the noise signaled some sort of change in the hull structure.
This may have changed the way the submarine was able to respond to the pressures of the depths.
Mr Kramer pointed out several other problems with the submarine’s design, including that the porthole window was not designed to dive to the depths of the Titanic and that the unusual shape of the hull prevented even distribution of pressure.
