Missing Titanic submarine: Five things that may have gone wrong

Missing Titanic submarine: Five things that may have gone wrong. It is another mystery of the deep.

As hopes fade for the five wealthy Titanic tourists who vanished while exploring the wreck aboard a mini submarine – one question keeps being asked.

What happened?

It is possible that no one will ever know after the sub, called Titan, suddenly went silent hundreds of miles off the coast of Canada and around 13,000ft underwater beside the Titanic.

On board were five men including a British billionaire, one of Pakistan’s richest men and his son, a famed French explorer, and the CEO of the company running the dive.

But submarine experts agree that five possible accidents are the most likely cause.