Titanic expedition highlights risk of deep-sea tourism, experts say

TAMPA, Fla. - The Coast Guard now believes the submersible Titan had a "catastrophic implosion." The announcement came after debris from the submersible carrying five people to the Titanic's wreckage was discovered. 

A former Submarine Commander who spoke with FOX 13 says this was the most likely scenario after the vessel’s disappearance on Sunday.

"I think there was a defect that was somewhere in there right at the beginning. But of course, on the surface it doesn't really matter, because there's the pressure it's not great and there could be a tiny crack," David Marquet, the former submarine commander, said.

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He says the implosion would’ve been quick if that were the case as the pressure changed.

"You get to a certain depth and boom. And it just happens fast and instantaneous that they didn't feel anything," Marquet said. "They might not even have known anything. And I'm thankful for that. I'm sad about what happened."

Experts say this tragedy points to the risk of deep-sea tourism. It’s a growing industry that doesn’t face a lot of regulation. Attorneys say with a vessel of this small size, that’s unlikely to change.

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"It's a particular area in which we wouldn't expect the government to get involved, because this is not something that is available to the general public," Theresa Bennett with Admiralty & Maritime Law said.

Marquet says his hope is as much of the vessel as possible can be recovered to get a better idea of what happened.