An inquiry into the doomed final descent, held in South Carolina, is expected to last two weeks.
Among the last words heard from the crew were “all good here”, it emerged on Monday. The crew lost radio contact with a support team on the surface after an exchange of texts about the submersible’s depth and weight.
The disappearance prompted a deep-sea search amid immediate fears for oxygen levels and the safety of the five people on board. The US Coast Guard had estimated that if the Titan was not breached the oxygen in the submersible was likely to last from 70 to 96 hours.
The exact cause of the implosion is still under investigation, but there has been intense scrutiny of Seattle-based OceanGate’s past legal and regulatory battles.
David Lochridge, the company’s former director of marine operations, was sacked in 2018 and subsequently sued by the company after he became a whistleblower over safety concerns about the Titan.
On Tuesday, Mr Lochridge told the inquiry that the tragedy could have been prevented if US safety authorities had listened to his warnings. He also criticised OceanGate’s company culture as being obsessed with “making money” and offering “very little in the way of science”.