Ship footage captures sound of Titan sub imploding

The footage was recently obtained by the USCG and shows Wendy Rush, the wife of Mr Rush, hearing the sound of the implosion while watching on from the sub's support ship and asking: "What was that bang?"

The video has been presented as evidence to the USCG Marine Board of Investigation, which has spent the last two years looking into the sub's catastrophic failure.

The documentary also reveals the carbon fibre used to build the submersible started to break apart a year before the fatal dive.

Titan's support ship was with the sub while it was diving in the Atlantic Ocean. The video shows Mrs Rush, who was a director of Oceangate with her husband, sitting in front of a computer that was used to send and receive text messages from Titan.

When the sub reaches a depth of about 3,300m, a noise that sounds like a door slamming is heard. Mrs Rush is seen to pause then look up and ask other Oceangate crew members what the noise was.

Within moments she then receives a text message from the sub saying it had dropped two weights, which seems to have led her to mistakenly think the dive was proceeding as expected.

The USCG says the noise was in fact the sound of Titan imploding. However, the text message, which must have been sent just before the sub failed, took longer to reach the ship than the sound of the implosion.

All five people on board Titan died instantly.

Prior to the fatal dive, warnings had been raised by deep sea experts and some former Oceangate employees about Titan's design. One described it as an "abomination" and said the disaster was "inevitable".

Titan had never undergone an independent safety assessment, known as certification, and a key concern was that its hull - the main body of the sub where the passengers sat - was made of layers of carbon fibre mixed with resin.

The USCG says it has now identified the moment the hull started to fail.

Carbon fibre is a highly unusual material for a deep sea submersible because it is unreliable under pressure. A known problem is that the layers of carbon fibre can separate, a process called delamination.

The USCG believes that the carbon fibre layers of the hull started to break apart during a dive to the Titanic, which took place a year before the disaster - the 80th dive that Titan had made.

Passengers on board reported hearing a loud bang as the sub made its way back to the surface. They said that at the time Mr Rush said that this noise was the sub shifting in its frame.

But the USCG says the data collected from sensors fitted to Titan shows that the bang was caused by delamination.

"Delamination at dive 80 was the beginning of the end," said Lieutenant Commander Katie Williams from USCG.

"And everyone that stepped onboard the Titan after dive 80 was risking their life."

Titan took passengers on three more dives in the summer of 2022 - two to the Titanic and one to a nearby reef, before it failed on its next deep dive, in June 2023.

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