Titanic sub implosion: Was the deep ocean vehicle safe?

The implosion of a submersible touring the deep-sea wreckage of the Titanic, killing all five passengers on board, has prompted questions about the regulations overseeing such voyages — and whether the vehicle itself was safe.

On Friday, the company responsible for the tour, OceanGate Expeditions, defended the decisions of its chief executive Stockton Rush, who died on board the submersible.

“Stockton was one of the most astute risk managers I’d ever met. He was very risk-averse,” Guillermo Söhnlein, OceanGate’s co-founder, told the news agency Reuters. “He was very committed to safety.”

But in the days since the submersible first went missing, passengers have come forward to share their stories of glitches and mishaps on expeditions to the ocean floor.