The astonishing collapse 4km below the ocean's surface: an encounter with instant death

At a depth of two-and-a-half miles or approximately three thousand, eight hundred and twenty-one meters beneath the ocean's surface, the pressure becomes an astounding three-and-a-half tons per square inch. To withstand this extreme force, the submersible's windows are constructed to be nine inches thick. However, the consequences of window failure would be dire, lasting only a mere two microseconds.

Unveiling the Mystery: The Tragic Tale of the Titan Submersible

The above quote from James Cameron's iconic film Titanic has gained attention online due to its chilling relevance to the recent disappearance of the Titan submersible in the North Atlantic. During its descent to the ocean's depths, the submersible, carrying five passengers, vanished, leaving behind only debris located approximately 487 meters away from the Titanic's bow at a depth of 3.8 kilometers. The U.S. Coast Guard concluded that the vessel experienced a "catastrophic implosion," resulting in the loss of all lives on board and extinguishing any hopes of a rescue.

Unveiling the Environmental Conditions: The Causes of Extraordinary Pressure

What exactly causes the extraordinary pressure in the depths of the deep sea? According to the American Museum of Natural History, atmospheric pressure is the force exerted by the weight of the air above us. It can be visualized as a towering column of air extending from your location to the outer reaches of the atmosphere, exerting pressure on the top of your head.

As we ascend to higher altitudes, the atmospheric pressure decreases due to the reduced weight of the air column pressing down on our bodies. At sea level, the pressure we experience is typically one atmosphere, which can be imagined as approximately one kilogram of weight pressing down on every square centimeter or 14.7 pounds per square inch (PSI).

In the ocean, the pressure intensifies due to the weight of the water above us, as water is much denser than air. For every 10 meters of depth in the ocean, the pressure increases by one atmosphere.

Diving Into the Depths: The Astonishing Pressure in the Deep Sea

The depth at which the Titanic wreck rests subjected the Titan submersible to an astounding pressure ranging from 375 to 400 atmospheres. This amounts to approximately 2500 kilograms (5500 pounds) of force pressing down on every square inch.

To provide a different perspective, Associate Professor Eric Fusil, the director of the Shipbuilding Hub at the University of Adelaide, explains that the immense pressure in the deep sea is equivalent to over 4000 tonnes of force applied to a one-square-meter area.

A Remarkable Demonstration: The Effects of Pressure on Objects

The profound impact of this pressure was vividly demonstrated during Australian marine archaeologist Emily Jateff's 2005 expedition to the Titanic. Jateff attached a bag filled with styrofoam cups to the exterior of the submersible she traveled in. As a result of the pressure at such depths, the cups were drastically compressed to about one-eighth of their original size.

According to Fusil, this level of pressure can be compared to crushing a soda can in your hand until it shrinks down to the dimensions of a very small marble.

The Catastrophic Implosion: Understanding the Tragic Outcome

The implosion that led to the catastrophic destruction of the Titan is a phenomenon characterized by the collapse of a pressure vessel due to external compression. This devastating event occurs within a mere 20 milliseconds, resulting in the loss of all lives on board.

The rapidity of the implosion surpasses the brain's capacity to process information, leaving the individuals on board with no opportunity to comprehend the unfolding events.

The significant pressure difference between the interior of the hull, maintained at one atmosphere, and the 400 atmospheres prevailing in the surrounding depths highlights how even a minute fracture or flaw could have triggered the implosion of the Titan.

Mitigating Risks: Designing Submersibles to Withstand Pressure

To mitigate the risks associated with deep-sea exploration, it is crucial to employ shapes like spheres or cylinders that possess inherent structural stability to balance the stresses within the material. Additionally, the materials used must have the capability to endure exceptionally high stresses.

In contrast to other submersibles designed for extreme depths, which are constructed using a single metallic material such as titanium, the Titan utilized a combination of two materials: titanium for the end caps and a composite carbon fiber for the body.

Titanium was chosen for its high-yield strength, enabling it to easily absorb deformation under a wide range of pressures. The titanium pressure vessel had the ability to contract and regain its original shape without suffering permanent deformation, a property known as plastification.

On the other hand, carbon fiber is renowned for its stiffness and resistance to movement. As Fusil explains, the Titan featured a combination of two materials with opposing behaviors.

The Vulnerabilities: Potential Flaws and Challenges

Speculatively, Fusil suggests that a defect might have occurred during the bonding process between the composite material and the titanium components. This analysis aligns with the views of retired US Navy Captain Alfred McLaren, who emphasizes the challenges of sealing dissimilar materials subjected to varying depths and temperatures. The differing reactions of the molecules in such situations can potentially introduce vulnerabilities.

McLaren further emphasizes that with each deep-sea voyage undertaken by a submersible, the risk of encountering defects increases. Even a minuscule flaw, such as a hole in the submersible's seal, no larger than the diameter of a strand of hair, could have catastrophic consequences.

The Tragic Fate: The Instantaneous Loss of Lives

In the event of an implosion, the passengers would have been instantaneously killed either by the folding metal or by the crushing pressure, which would have collapsed the air-filled spaces in their bodies, including their lungs. The submersible would have flooded rapidly, and the lives of the occupants would have been extinguished within a fraction of a second, as described by McLaren.

Unraveling the mysteries of extreme pressure in the deep sea is crucial not only for the advancement of scientific knowledge but also for enhancing the safety and reliability of future submersible expeditions. As we strive to push the boundaries of exploration, understanding the forces that lie beneath the ocean's surface becomes vital to safeguarding human lives and uncovering the secrets hidden within the depths.