Source scope
This article uses the Thai ASR transcript in workbook [18_00-19_00]9arm_.xlsx, Videos!D21 (36,539 characters with no timecodes), to identify the topics discussed in the video. It checks accident and engineering facts against the official NTSB report MIR-25-36 and separates those findings from the speaker’s explanation.
The video audio has not been reviewed, so this article cannot confirm that the ASR is complete or accurate and does not claim to have checked the speaker’s exact words. The engineering discussion below follows NTSB MIR-25-36, preserving key terms and the status of the report’s findings. It is not advice on designing or operating a submersible.
Read this article alongside the original 9arm video, “Summary of the Titan submersible investigation.” The video walks through the NTSB report after the investigation and discusses the hull structure and monitoring system. This article uses the official final report as its main factual source.
Visit the 9arm video directory or read the related article about the Titan before the final investigation report to see how the available information changed.
What the NTSB report says happened
The NTSB’s Marine Investigation Report MIR-25-36 says that on June 18, 2023, the Titan lost pressure-vessel integrity while diving to the Titanic wreck. The submersible imploded, killing all five people aboard. The final report is dated October 2, 2025.
The NTSB identified the probable cause as OceanGate’s inadequate engineering process for determining the pressure vessel’s actual strength and durability, together with continuing to operate a damaged vessel. The NTSB worked with the Coast Guard in the investigation. A safety report is not a civil-liability judgment.
Damage associated with dives 80, 82 and 88
- After dive 80: The NTSB said the pressure vessel likely developed at least one delamination between material layers, weakening the structure.
- After dive 82: The report found additional damage whose origin was unknown, further degrading the pressure vessel.
- Dive 88: Accumulated damage before this dive led to local buckling and failure of the pressure vessel.
The NTSB did not conclude that “carbon fiber caused the accident” by itself. The report discussed damage to the component and its bonded layers, insufficient testing, an incorrect assessment of actual strength, and the decision to continue using the vessel after damage information was available.
Monitoring data existed, but analysis was inadequate
The 9arm video explains a real-time monitoring system that recorded strain-gauge and acoustic-emission data during dives. The NTSB report says OceanGate’s analysis of pressure-vessel monitoring data was deficient, allowing the damaged submersible to continue operating. The findings concern design, testing, data interpretation and safety decisions together—not simply whether sensors were present.
Search findings and regulatory oversight
The NTSB said OceanGate did not notify search-and-rescue authorities of its voyage plan. The report said that following the cited emergency response plan could have allowed responders to prepare resources and locate the wreckage sooner, even though it concluded that the people aboard could not have been saved in this event. Separately, the NTSB found that U.S. Coast Guard search-and-rescue coordination was effective and led to the Titan wreckage being found in a timely manner.
The report also found that the voluntary guidance and oversight for small passenger vessels in the United States at the time did not adequately address pressure vessels for human occupancy (PVHO). The NTSB recommended that the U.S. Coast Guard study standards with experts, develop U.S. rules, revise guidance NVIC 05-93 and propose relevant international standards through the IMO. These are recommendations in the report, not confirmation that all of the proposed rules are already in force.
Frequently asked questions
What did the NTSB identify as the probable cause?
The NTSB identified an inadequate engineering process for determining the pressure vessel’s actual strength and durability, along with continued use of a damaged vessel. The resulting damage accumulated and led to local buckling.
Did the report say carbon fiber was the only cause?
No. The report discusses pressure-vessel damage together with design and testing, analysis of monitoring data and inadequate oversight.
Did the NTSB blame the Coast Guard for a delayed search?
The report says OceanGate did not notify search-and-rescue authorities of its voyage plan. It also says U.S. Coast Guard search-and-rescue coordination was effective and led to the wreckage being found in a timely manner.
Is an NTSB report a legal ruling on liability?
No. The NTSB says its investigations identify causes and make safety recommendations; they do not decide the civil rights or liability of individuals or companies.