A toxic culture of belittling and retaliation within operator OceanGate was one of the factors which led to the Titan submersible's deep-sea implosion, the US Coast Guard has found.
The submersible was descending on an expedition to visit the Titanic's undersea wreckage in June 2023 when it experienced "a loss of structural integrity", the report found.
The disaster resulted in the deaths of all five people on board, including OceanGate's chief executive Stockton Rush.
In an extensive 300-page report into the disaster, the US Coast Guard determined that the Titan's structural failure could have been avoided.
But employees of its operator OceanGate were "belittled for voicing concerns" and that Mr Rush in particular ignored key safety checks and "deliberately sidelined" the company's board.
"OceanGate's management actively retaliated against employees who raised legitimate compliance related concerns," the report found.
"Decisions were made unilaterally at the top, with Mr Rush often bypassing established protocols and ignoring the concerns of other experienced OceanGate employees and contractors."
The Coast Guard likewise found significant structural engineering problems associated with the Titan, including "the use of unproven materials in the deep-sea environment".
It found OceanGate showed a "disregard for the necessary safety protocols" when designing, building and testing the vessel.
"Mr Rush's overconfidence influenced OceanGate's personnel, contractors, and mission specialists, creating an environment where safety concerns were ignored or underemphasised in favour of operational continuity.
"The analysis reveals a disturbing pattern of misrepresentation and reckless disregard for safety in OceanGate's operation of the TITAN submersible, with Mr Rush seemingly using inflated numbers to bolster the perceived safety and dive count of the final TITAN hull."
Disaster was 'preventable'
Mr Rush, Shahzada Dawood and his son Suleman Dawood, Hamish Harding, and Paul-Henri Nargeolet were declared dead days after the vessel first went missing on June 18, 2023, in a remote area of the North Atlantic.
A deep-sea robot later found pieces of its wreckage on the sea floor less than 500 metres from the Titanic, four kilometres below the ocean surface.
In its report into what it deemed a "preventable tragedy", the US Coast Guard found there were significant concerns raised during the design and testing of the vessel that went unheeded by OceanGate and its chief executive.
It also found that there had been warning signs of "potential damage" to the vessel's hull at least a year prior to the disaster.
"Had OceanGate taken the warnings more seriously, involved independent safety experts, or adhered to more rigorous testing and safety protocols, many of the risks that contributed to the eventual implosion could have been mitigated or avoided entirely.
"Instead, the company’s systemic failures created an environment where risks were ignored, and consequences were inevitable."
OceanGate's financial situation and subsequent cost-cutting also meant the submersible was stored outdoors during the Canadian winter, likely contributing to the hull's weakening.
