The company that built and operated the ill-fated Titan submarine did not originally plan to develop its own vessels, its co-founder testified Monday before a U.S. Coast Guard panel investigating what caused the vessel to implode last year, killing all five people aboard.
A two-week hearing of the Marine Board of Investigation resumed Monday with testimony from Guillermo Sohnlein, who co-founded OceanGate with Stockton Rush in 2009. Sohnlein, who served as CEO for a time, left the company in 2013, 10 years before Rush and four others died in the implosion while diving on the wreck of the Titanic in the North Atlantic.
Businessman Shahzada Dawood and his 19-year-old son Suleman Dawood, businessman Hamish Harding and French diver Paul-Henri Nargeolet also died in what authorities described as a "catastrophic implosion".
Sohnlein was not involved in the development of Titan, CNN previously reported. But his testimony shed light on OceanGate's origins, early years and the founders' goals for the company: expanding humanity's access to the deep ocean.
OceanGate initially hoped to have a fleet of five submarines that could dive to 20,000 feet (6,000 meters) deep and wouldn't need a dedicated mother ship, Sohnlein said, giving the fleet the flexibility to be chartered anywhere in the world as oceanographic research vessels. The plan was for researchers to pay to collect their data aboard one of OceanGate's submarines, Sohnlein said.
But when the company discussed its requirements with submarine manufacturers, no one could deliver what OceanGate needed, Sohnlein said. As entrepreneurs, he and Rush faced two choices: "You either change your business model or you find a better technical solution."
"And Stockton, being the engineer that he was, chose to find a better technical solution," Sohnlein said. The company would have to build its own submarines.
It was around this time, Sohnlein said, that OceanGate first considered using carbon fiber to build a pressure hull, a part that was eventually used in the Titan.
The construction of the ill-fated submarine has become a major investigative topic for the Coast Guard panel. Last week, the panel heard testimony that Sohnlein's former company and business partner put profits ahead of science and safety. And warnings were repeatedly ignored before the Titan imploded.
Sohnlein, however, disputed this testimony, portraying Rush as an explorer who conducted Titan's first dive to 13,000 feet (4,000 m) alone to prevent others from taking the same risk.
"Neither Stockton nor I were ever motivated by tourism," he said, referring to the expeditions OceanGate would eventually conduct to bring deep-pocketed clients to the site of the Titanic. "We were never motivated by going where people had been before. The reason we got into this was because we both wanted to explore."
The submarine lost contact with its support vessel, the Polar Prince, an hour and 45 minutes into the dive on June 18, 2023. The wreck, which was a few hundred yards from the Titanic, was found June 22 after an extensive search, according to the Marine Board of Investigation, the Coast Guard's top investigative body.
According to industry experts, it was the first time a manned deep-sea submarine imploded.
'Smoke and mirrors'
On Monday, the board also heard from Roy Thomas, an engineer with the American Bureau of Shipping, whose testimony highlighted the risks of using carbon fiber in hull construction.
The agency provides classification services, a process to ensure that ships meet certain standards. Thomas said OceanGate has not applied for classification from the agency. OceanGate acknowledged that the Titan was not classified in a 2019 blog post, CNN previously reported.
It was important that the hull be built of "robust materials" with a documented history of "external pressure applications," Thomas said. For the desk, materials included steel, aluminum, titanium and, for the windows, acrylic plastic.
Carbon fiber doesn't hold up well when exposed to external pressure, Thomas said, and is "prone to fatigue damage," which can remain hidden. Manufacturing defects are another concern, he said.
"Currently there are no recognized national or international standards for carbon fiber pressure hulls for human habitation," Thomas said.
Last year, Sohnlein told "CNN This Morning" that safety has always been a top priority for OceanGate and Rush, whom he described as a "very strong risk manager."
"I believe he believed that every innovation he created, whether it was technological or within diving operations, was intended to both expand humanity's ability to explore the oceans and improve the safety of those who did so," Sohnlein said.
But last week's testimony, including from key witness and former OceanGate director of maritime operations David Lochridge, told a different story about Rush and his views on the ship's safety.
Lochridge, who described the company as focused on "making money" and offering "very little in the way of science," testified that he had expressed concerns about the safety of OceanGate's operations in 2018 and that he had "no confidence at all" in the way the Titan was being built.
"It was all smoke and mirrors," Lochridge said of how the company he was fired from in 2018 operated. "All that social media you see about all those previous expeditions. They always had issues with their expeditions."
On Thursday, a marine scientist who dived aboard Titan as a crew member last year during its fourth mission testified that the submarine experienced a platform failure six days before it imploded.
Steven Ross, who said the Coast Guard did not inspect the Titan in 2021, 2022 or 2023, said the platform malfunctioned June 12, causing the five passengers aboard to slam into the back of the submarine for at least an hour during that trip. The dive was piloted by Rush and was aborted, according to Ross, who said no one was injured.
Others testified last week that Rush, an aerospace engineer, knowingly broke the rules when he piloted an experimental submarine that had not been thoroughly tested in order to make himself more attractive to wealthy tourists and researchers seeking deep-sea voyages.
Antonella Wilby, a former engineering contractor for OceanGate, testified Friday that her repeated concerns about the Titan's safety were ignored and that the submarine's navigation and acoustic communications systems failed during a 2022 expedition.
"No aspect of the operation seemed safe to me," said Wilby, who was eventually removed from the communications and navigation teams. "When you're answering specific questions with, 'That's just what the founder of the company wants,' instead of actual design decisions and data and analysis, that was a red flag to me."
CNN's Ray Sanchez, Alaa Elassar, Cindy Von Quednow, Isabelle Chapman and Curt Devine contributed to this report.For more CNN news and newsletters, create an account at CNN.com