Lessons Learned: What Happened to the Titan Submersible?

Five people died when the commercial submersible Titan imploded on June 18, 2023, in what is considered to be a preventable tragedy.

The U.S. Coast Guard (USCG) Marine Board of Investigation looked into the fatal incident and found that OceanGate’s failure to follow established engineering protocols for safety, testing, and maintenance of their submersible, was the primary causal factor. The investigation further identified the need for proper corporate governance, a professional workplace culture, and improved regulatory oversight, in particular for novel vessel designs and operations.

A report from DOE OPEXshare discusses NSTB’s (National Transportation Safety Board) findings on the hull failure and implosion of the submersible Titan, manufactured and operated by OceanGate, while diving to the Titanic wreck in the North Atlantic Ocean. There were five fatalities, and the vessel was a total loss, according to a 2023 customs declaration. The submersible’s value, combined with its launch and recovery system, was estimated to be about $4.2 million USD.

You can watch our Navy Submarine experts discuss the incident here.

Titan safety issues identified include OceanGate’s inadequate engineering process for the Titan; OceanGate’s flawed analysis of Titan strain gage and acoustic emission (real-time monitoring system) data as a measure of pressure hull integrity; OceanGate’s failure to notify search and rescue assets about its planned expedition; and insufficient voluntary guidance and US regulations for pressure vessels for human occupancy.

As a result of this investigation, NTSB made four new safety recommendations to the US Coast Guard.

1. Commission a panel of experts to study current pressure vessel for human occupancy (PVHO) operations, including, at a minimum, the availability of domestic and international design and construction standards; the competency and credentialing of persons on board; the distinction between crew and passengers and whether all PVHOs should be inspected regardless of operational category; maintenance and operation of submersibles; the effects of operational changes, such as storage conditions and towing; failure modes and best practices; and emergency response procedures, and disseminate findings of the study to industry. (M-25-012) Implement US regulations for pressure vessels for human occupancy informed by the findings of the study recommended in Safety Recommendation M-25-012. If necessary, obtain legislative authority to act on this recommendation. (M-25-012)

2. Implement US regulations for pressure vessels for human occupancy informed by the findings of the study recommended in Safety Recommendation M-25-012. If necessary, obtain legislative authority to act on this recommendation. (M-25-013)

3. Revise Navigation and Vessel Inspection Circular 05-93 to include the revised definition of small passenger vessel as reflected in the Passenger Vessel Safety Act of 1993 and to reflect the findings of the study recommended in Safety Recommendation M-25-012. (M-25014)

4. Propose that the International Maritime Organization make MSC.1/Circ. 981 mandatory to promote consistent application of pressure vessel for human occupancy rules among member states. (M-25-015)

The US Coast Guard was the lead US federal agency in this investigation. The National Transportation Safety Board (NTSB) learned of this casualty from the Coast Guard on June 18, 2023. NTSB investigators traveled to Newfoundland and Labrador, Canada; Washington; North Carolina; and Rhode Island to inspect the wreckage of the Titan and exemplar equipment and to interview OceanGate staff. Wreckage retrieved from the accident site by the Odysseus and the Horizon Arctic was taken to Rhode Island by the Coast Guard buoy tender Sycamore.

The Coast Guard additionally contracted with the US Navy’s Supervisor of Salvage (SUPSALV) to retrieve additional wreckage from the accident scene, accompanied by NTSB and Coast Guard investigators, in September 2023, retrieving the aft dome and an external camera among the wreckage. NTSB investigators also participated in the Coast Guard Marine Board of Investigation hearings in September 2024.

Content: DOE OPEXshare, “US Coast Guard/NTSB Titan Implosion,” October 2025.