Structural errors likely led to submersible implosion

Questions continue after debris from the recreational submersible Titan is found floating near the site of the HMS Titanic wreckage in the North Atlantic. 

Those on board were U..K. billionaire Hamish Harding, Pakistani businessman Shahzada Dawood and his son Sulaiman Dawood, as well as the CEO of the submarine company, OceanGate’s Stockton Rush, and French diver Paul-Henri Nargeolet.

Evan Lemley, UCO’s assistant dean of the School of Engineering, Dr. Evan Lemley, said investigators will not know exactly how the submersible imploded until engineers look at how the debris is bent and crushed. He described the Titan as a “really unconventional design.”

Lemley said that most submarines are spherical structures so that they experience equal pressure from all directions. They also are built with titanium exteriors. In contrast, the Titan was spherical except for the sharp tail at the back of the submersible. The Titan also was fitted with titanium at the front and back, but the middle of the submersible was made of carbon fiber. This material is not common for watercraft.

Lemley said carbon fibers are thin strips of carbon atoms, and are usually found in airplanes and race cars. Where they reduce the weight of the object.

The center of the submersible had five inches of carbon fiber wrapped around it. That’s 480 layers of carbon fiber that were “glued” together, creating a cause for concern if air bubbles were trapped between the layers, which could cause cracking, Lemley said. 

Another location of stress would be the tail — another plausible cause of the implosion, Lemley said.

OceanGate took the Titan down on 50 test dives to the Titanic and experienced no reported problems. In 2018, an engineer for OceanGate warned of the “catastrophic” risks of diving in the tank.

Lemley said sending the Titan 50 times under 10,000 feet of water can cause the carbon fiber to fail over time. Lemley said this is called fatigue.

There was no certification test on OceanGate’s watercraft. The Titan began its descent to the wreckage of the Titanic, on June 18. An hour and 45 minutes later, the Polar Prince, the ship that transported the submersible to the site, lost all contact with the Titian.

The next day, the Polar Prince sent out an alarm to notify the U.S. National Coast Guard about the missing submarine. 

Both the U.S. and Canadian coast guards began a 900-mile search off in the North Atlantic.

What OceanGate has shared with the media is the structure of the submarine. It is bolted from the outside and has an oxygen supply for up to 96 hours. 

The Titan was designed to resurface if technological failures arise. The trip underwater costs $250,000 per person. It included an eight-day excursion that promised to explore over 100 miles of the deep sea.