Mechanical engineering expert Eric Fusil takes a look at what ultimately happened to the crew of the ill-fated expedition.
Search and rescue officials have revealed that parts of the missing sub have been found on the ocean floor.
With time running out for the crew, experts have weighed in on the safety measures missing from the stricken sub.
The world's most famous unmanned submersible has made a triumphant return from its maiden voyage.
A two-man submersible was attacked by a pair of the invertebrates during an expedition in the Bering Sea.
A huge 26ft long magnapinna squid has been filmed by Shell from one of its submersible vehicles.