Marcel Muise, far left, National Transportation Safety Board, asks questions of Patrick Lahey, Triton Submarines, and subject matter expert for the Coast Guard Marine Board of Investigation (MBI) hearing into the loss of the Titan submersible in North Charleston, South Carolina, on Sept. 20, 2024. The hearing examines all aspects of the loss of the Titan, including pre-accident historical events, regulatory compliance, crewmember duties and qualifications, mechanical and structural systems, emergency response, and the submersible industry. (U.S. Coast Guard photo by Petty Officer 2nd Class Kate Kilroy)