"It just breaks my heart for their families, it's just very unbelievable," Bill Price told Eyewitness News. "It's so surreal."
Price was on the Titan in 2021 during a voyage with OceanGate chief executive and pilot Stockton Rush and Paul-Henri Nargeolet, both of whom died in Sunday's implosion.
Price is one of the few people who went on the sub to the bottom of the ocean. Images from 2021 show him inside the vessel visiting the wreck of the Titanic.
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Even back then he says there were issues: the vessel lost communication an hour into the journey and a propulsion unit wasn't working. Neither was a mechanism that releases weights and allows the sub to rise back up.
"At that point Stockton had decided to try to manually release the weights, so we had gone through a process of rolling the sub back and forth, and fortunately we were able to dislodge the weights and rise back up," Price said recalling his first trip on the sub.
Having gone through that the first time, Price said he agreed to go on another trip with Rush and Nargeolet the next day. This time, he was able to see the Titanic wreckage.
"The first time we experienced the difficulties I was not scared. I had full confidence in both Stockton and P.H.," Price said. "They are very experienced and they have a lot of technical knowledge. I think that the whole crew was calm and collected."
The vessel suffered a catastrophic implosion, killing all five aboard, sometime after it submerged Sunday morning. It's not clear exactly when or where the implosion occurred, but a U.S. Navy acoustics system detected an "anomaly" Sunday that was likely the Titan's fatal implosion.
The Coast Guard announced that debris from the submersible had been found and the end of rescue efforts Thursday, bringing a tragic close to a saga that included an urgent around-the-clock search and a worldwide vigil for the missing vessel.
A deep-sea robot discovered the debris, near the Titanic shipwreck, that authorities say came from the submersible.
The tragedy is raising questions about OceanGate's sub design and operations.
Price said he was confident when he went on the Titan.
"It was not a charlatan scenario. It was not a fly by night," Price said. "It was very sophisticated operation. The people involved were extremely careful, very technical and checked and double checked and triple checked everything, so it's important that people know that."
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The Associated Press contributed to this report.