OceanGate's 'Titan' submarine used new untested engineering which was 'experimental; a submarine expert has said.
All five men onboard were killed when the submarine 'Titan' imploded on a voyage to the wreckage of the Titanic on June 18.
And now the president of a company which offers similar deep-diving trips has said that the submersible was not tested thoroughly enough before being sent into the ocean.
