DALLAS (CBSNewsTexas.com) – When CBS News Texas first interviewed Bob Curtis earlier this week, he said the odds the OceanGate's Titan passengers were still alive weren't good. 

"What was concerning to professionals around the world was zero communication," he said. "It would've taken a catastrophic electronic failure to make that happen, but still there are backup systems."

Curtis knows submarines inside and out. He's built them from scratch, having done work for commercial clients and the military. He says what happened with the Titan was catastrophic implosion.  

"The water pressure is so intense, so intense that this slightest breach and you have this immediate implosion and explosion," he said. "So for anybody in there, they didn't feel a thing." 

One of the biggest questions is, could this have been prevented? 

"This unfortunately was not something that was scrutinized," he said. "What you certainly want to do is invite to peer review.. and unfortunately, there wasn't a lot of that going on." 

Now, Curtis says multiple investigations will continue between the U.S Navy, Canada's Transportation Safety Board and industry organizations. 

"Why did that happen?" he said. "Why didn't we have more backup systems? How do we prevent it from happening again?"

Curtis says what will eventually come from this is international recommendations.