The Causes of the Tragedy of Titan’s Batiscap

A year after the tragic implosion of the Titan, American Coast Guard (US Coast Guard) continues a complex investigation into the causes of the disaster. The investigation to prevent similar incidents in the future will take longer than initially expected.

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The disaster of Titan’s batiscap — a year later

June 18 will be exactly one year since the Titan submersible, belonging to OceanGate Expeditions, during a mission to the wreck of the Titanic, lost contact with the Canadian research ship (mother ship) Polar Prince. Within an hour and 45 minutes after the start of the cruise, the contact was discontinued, which started an international search and rescue operation.

An ongoing year of investigation revealed that the disturbing record of communication between the Titan batiskaf and his mother ship, which was distributed by millions of people on the Internet, was entirely false. One of the U.S. portals allegedly described in detail the last communication between the batiscaf trying to reach Titanic with five passengers on board and the mother ship. Captain Jason D. Neubauer, Chairman of the Marine Investigation Council, confirmed that his team of investigators had found no evidence that the people aboard Titan knew there would be a fatal implosion. "I am convinced that this false transcription... was made up," Neubauer said. Neubauer hopes that the truth about transcription will bring comfort to the families of five men aboard Titan, knowing that they did not suffer during the last moments of their lives.

American Coast Guard announced that her investigation into the implosion of Titan's batiscaf, which was initially to last 12 months, would require more time.

We work intensively with our partners to ensure a comprehensive understanding of this incident. The need for two rescue missions to secure relevant information was one of the reasons for extending the investigation. We are grateful for the international and interagency cooperation that was necessary for the recovery, preservation and forensic examination of evidence from a distant part of the ocean and extreme depths.
Jason Neubauer, Chairman of the Maritime Investigation Council (MBI)

Tragic loss and effects

Implosion Titan's batiscafu had disastrous effects. June 22, 2023, American Coast Guard announced that submersible He experienced a "catastrophic loss of the pressure chamber" during the descent, which was confirmed by the discovery of remains of approximately 900 nautical miles east of Cape Cod, Massachusetts.

The Death of Tragedy

Stockton Rush – Executive Director of OceanGate,
Shahzada Dawood – member of one of the richest Pakistani families,
Suleman Dawood, son of Shahzada Dawood,
Hamish Harding – British billionaire and traveller,
Paul-Henry Nargeolet – French diver and expert in the field of Titanic.

OceanGate, which charged $250,000 per person per person voyage aboard Titan, she suspended all operations in early July 2023 after numerous warnings regarding potential security issues.

Comparison with my analysis of 2023

It is worth recalling my analysis published a year ago, which met with great interest – read by over 40,000 people. It pointed to numerous technical and structural negligencees in Titan's batiskaf. My analysis described in detail the phenomenon of implosion caused by hydrostatic pressure at a depth of 3780 meters, which is about 400 kg/cm2. Then I used an example where I compared this pressure to a situation where three baths filled with water were placed on a single penny coin.

I also explained that while the phenomenon of explosion is commonly known, implosion, being its inverse in the sense of the direction of force response, is not so common. A common feature of both is the dynamic response to the pressure differential. This is most often analysed in the context of phenomena such as cavitationwhere microbubbles When imploding, the vapours act destructively on vacuum zones e.g. propellers and flow installations; tank installations where excessive fluid discharge (both liquid and gas) causes the tank to collapse inside; and vacuum bombs where the spray of the combustible substance after ignition creates an area of short-term vacuum, which then hits with a pressure wave.

The case of Titan's batiscaf most depicts the problem of tanks, where inside the passenger compartment walls 1 atmosphere (this is known from the surface) and externally 400 atmospheres resulting mainly from hydrostatic pressure at a depth of 3780 m. I also added that it is clear that submersible is extremely tight.

I stressed at the time that Titan had a positive buoyancy, but that was not enough to prevent the tragedy. I pointed out the fatigue of the material, the stresses resulting from the changes in pressure, and the underestimation of safety margins when selecting the thickness of the unit walls. My analysis highlighted deficiencies in emergency systems and deficiencies in performance quality, which could have contributed to the disaster. During the annual investigation, the cause of the marine disaster was not clearly established, which is related to a very specific situation that has no equivalent in history.

The unique features should be identified as the place of tragedy and the design, which premeditatedly avoided commonly used standards. While the uniqueness of the high-pressure environment itself has many problems with the easy completion of the evidence resulting from its dispersal, deformation and partial or complete sinking into the loose layer of the ocean floor sand, it is a very interesting issue to assess the relevance of the investigation of the causes of the disaster outside the scope of indicating the responsibility resulting from the expectations of the families of victims and claims ducts.

From a technical perspective, the analysis of the cause has two faces: one doubting its legitimacy resulting from the theory that the analysis of the tragedy of amateur construction when our engineering knowledge is far further and the other treating the uniqueness of this case as an area enriching our knowledge of the so-called "blind streets of development", which shows what to do in the case of the development of subsequent generations of boats and submarines.

Personally, I am more inclined towards this second concept with particular emphasis on the area associated with the cooperation of various critical materials, areas of construction such as the outer hull itself which is at the same time a manned compartment – I would point out that it was a single-plane structure, i.e. one where we have one hull without the other outer hull, the failure of which is not conclusively consistent with the death of the crew, and allows us to monitor its condition and respond in the event of failure.

In Titan's case, we have faced a very risky combination of composite materials and traditional ones like a titanium head. In this type of fusion, the problem is different elasticity and resistance to fatigue processes. While titanium is a proven and stable material while maintaining appropriate technological and quantitative regimes, composite materials are no longer.

These are characterized by far more flexibility and different characteristics of fatigue resistance. The combination of materials with different characteristics puts a huge requirement for this plane, both in the screw connection area and the sealing itself. Keep in mind that submersible While immersing and rising, he was subjected to a variable pressure of 0,14 g/cm2 being raised to 400000 g/cm2 being at the level of the wreck of the Titanic. The increase in these pressures and thus stress is more than 2.8 million times.

In addition, by adding safety margins, a calculation would take into account the increase in stress significantly higher, as a reference taking multiple cycles down to the depth and time between the technical repair facility. For example, one descent per month, inspection and diagnostic procedures after and before each immersion and general renovation after the cycle e.g. 2 years. Without the definition of refurbishment regimes, there is no possibility to select appropriate safety margins, and the accident is only a matter of the quantities carried out voyages. Let me repeat: if the Polish ship industry did submersible There would not be such a far-reaching recklessness towards an environment as extreme as the ocean depth.

Ongoing investigation and future action

In October, Coast Guard retrieved "additional probable human remains" and recent remains from Titan. Neubauer then stressed that MBI was making every effort to fully understand the factors that led to this tragedy. Through international cooperation, there is hope that future disasters of this type will be avoided. Understanding the causes of this tragic implosion is crucial to improving safety standards in deep sea exploration. This will allow better security of future missions and the lives of participants in such expeditions, including through stricter rules preventing implementation voyageThese are on amateur constructions.