A WHISTLEBLOWER RAISED SAFETY CONCERNS ABOUT OCEANGATE’S SUBMERSIBLE IN 2018. THEN HE WAS FIRED:

The director of marine operations at OceanGate, the company whose submersible went missing Sunday on an expedition to the Titanic in the North Atlantic, was fired after raising concerns about its first-of-a-kind carbon fiber hull and other systems before its maiden voyage, according to a filing in a 2018 lawsuit first reported by Insider and New Republic.

David Lochridge was terminated in January 2018 after presenting a scathing quality control report on the vessel to OceanGate’s senior management, including founder and CEO Stockton Rush, who is on board the missing vessel.

According to a court filing by Lochridge, the preamble to his report read: “Now is the time to properly address items that may pose a safety risk to personnel. Verbal communication of the key items I have addressed in my attached document have been dismissed on several occasions, so I feel now I must make this report so there is an official record in place.”

The report detailed “numerous issues that posed serious safety concerns,” according to the filing. These included Lochridge’s worry that “visible flaws” in the carbon fiber supplied to OceanGate raised the risk of small flaws expanding into larger tears during “pressure cycling.” These are the huge pressure changes that the submersible would experience as it made its way and from the deep ocean floor. He noted that a previously tested scale model of the hull had “prevalent flaws.”

Carbon fiber composites can be stronger and lighter than steel, making a submersible naturally buoyant. But they can also be prone to sudden failure under stress. The hull that Lochridge was writing about was made by Spencer Composites, the only company to have previously made a carbon fiber hull for a manned submersible. (That submersible was commissioned by explorer Steve Fossett for a record-breaking dive, but he died in a light aircraft crash before it could be used.)

Related: OceanGate took eight hours to report missing sub to Coast Guard after it lost contact — as Navy commander says crew has a ‘one percent chance of survival.’