The expert said he believes the deadly malfunction happened at a depth of around 5,500 feet, leading to the point where Titan could not be manoeuvred.
"The Titan changes position and falls like an arrow vertically because the 400 kilos (880 pounds) of passengers that were at the porthole unbalance the submersible," Martín explained.
"Everyone rushes and crowds on top of each other. Imagine the horror, the fear, and the agony. It had to be like a horror movie," the expert added, saying the free fall would have took anywhere between 48 and 71 seconds.
He said those on board would have realised what was happening, adding: "In that period of time, they are realising everything. And what’s more, in complete darkness. It’s difficult to get an idea of what they experienced in those moments.
"After those 48 seconds, or one minute, the implosion and instantaneous sudden death occurs."
An investigation into the implosion is ongoing.
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