BATON ROUGE - A local expert that specializes in deep ocean exploration is giving insight as to what went wrong on the Titan submersible's last mission. 

Parks Stephenson says a flaw in the design of the OceanGate Titan submersible could have been to blame for its implosion. He told WBRZ on Friday that he was approached years ago by OceanGate when the submersible was being built. 

"And this is just my opinion alone. The cause of the disaster was the design and construction of that vehicle," said Stephenson.

Stephenson believes the submersible should have been a spherical shape and built out of titanium. Instead, the sub was a cylindrical shape made from a variety of materials, including a carbon fiber hull. 

When mistakes are made in these situations, they can become fatal. That's why Stephenson is hoping the Titan disaster will serve as a wake up call.

"I want to add my voice to a growing number of voices who are calling for a law for all passenger carrying submersibles to be properly certified," Stephenson said.