The design of the vacationer submersible that has gone lacking whereas diving down 13,000ft to view the Titanic is "unconventional" and never like "anything else that has preceded it” says an experienced shipwreck hunter.

David Mearns also said "classes of some sort should be realized". And he said there should be a "rethink" about future expeditions to view the Titanic, with an investigation into how and why the sub called Titan went missing.   

The five-man craft, owned and operated by OceanGate Expeditions, whose CEO Stockton Rush is one of the five people on board, lost communications with its mothership on Sunday (June 18) and now there is a race against time to locate the vessel before the oxygen supply runs out on Thursday.

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Mearns, a marine scientist and oceanographer who has made a reputation for himself by discovering quite a few historic shipwrecks, has raised considerations in regards to the Titan craft's design.  

“The sub is no doubt an unconventional design and build, including the launching systems,” he advised LBC. “It’s not like anything else that has preceded it.”

Made from titanium and filament-wound carbon fibre, the submersible has 4 electrical thrusters which are piloted with a modified Logitech gaming controller and Mearns feels that earlier than any extra journeys are made to the Titanic, there must be some critical conversations about any future journeys to the legendary wreck.

“Whatever happens, and hopefully all five men come home safely, I think there’s going to be an investigation and a rethink about this type of activity,” Mearns added. “Lessons of some type need to be learned.”

It is designed to hold as much as 5 individuals and constructed to dive to depths of 13,123 toes and journey at three knots (3.5mph). The craft is 22 toes lengthy and weighs 23,000lb.

Mearns is aware of two of the boys on board, UK billionaire Hamish Harding and former French navy commander Paul-Henri Nargeolet.

“I know both men – one professionally and one socially – they are from completely different backgrounds and positions in life, but I know they would’ve got on together like a house on fire,” Mearns went on.

“They’re two characters so it would not surprise me if we learned that Hamish requested that PH join him – he knows the debris field and he knows the two bits of Titanic as well as anybody does.

“Theres probably only one or two people who have done more dives to the site than he has.”