Missing Titanic submersible live updates: Texts show OceanGate CEO dismissed concerns

Five people, including the company CEO, were aboard the sub when it imploded.

All passengers are believed to be lost after a desperate dayslong search for a submersible carrying five people that vanished while on a tour of the Titanic wreckage off the coast of Newfoundland, Canada.

The 21-foot deep-sea vessel, operated by OceanGate Expeditions, lost contact about an hour and 45 minutes after submerging on Sunday morning with a 96-hour oxygen supply. That amount of breathable air was forecast to run out on Thursday morning, according to the United States Coast Guard, which was coordinating the multinational search and rescue efforts.

RCMP to investigate the deaths aboard Titan sub

Officials with Canada's Transportation Safety Board said at a press conference Saturday that they have begun speaking with people on board the Polar Prince, which launched the ill-fated Titan submersible.

The Polar Prince returned to its port, St. John's, Newfoundland, on Saturday morning.

"I would say that we've received full cooperation," TSB Director of Marine Investigations Clifford Harvey said. "It's been a really good interaction thus far and is really getting full cooperation with all the individuals involved."

In addition, the Royal Canadian Mounted Police (RCMP) said they are "examining the circumstances" of the deaths on board Titan, and will launch a full investigation if "the circumstances indicate criminal, federal or provincial laws may possibly have been broken."

-ABC News' Matt J. Foster

US taxpayer cost for search and rescue may be $1.5 million, expert says

A defense budget expert estimates once the U.S. military participation concludes, the cost for the search and rescue mission of the five passengers on board the Titan submersible will cost the U.S. around $1.5 million.

Mark Cancian, a senior advisor with the Center for Strategic and International Studies, came up with the estimate based on aircraft sorties, cross referencing the U.S. Department of Defense cost numbers, Coast Guard Cutter costs and flying hour costs. He said some costs have already been set aside in various budgets, with resources simply diverted to the site.

He emphasized that these are strictly well-informed guesses.

A spokesperson for the Coast Guard's District 1 in Boston would not give an estimate of costs so far, saying, "We cannot attribute a monetary value to Search and Rescue cases, as the Coast Guard does not associate cost with saving a life."

-ABC News' Jaclyn C. Lee

US Coast Guard to lead sub investigation

The U.S. Coast Guard will be the organization leading the investigation into the OceanGate sub incident.

The NTSB announced the news on Friday via Twitter, noting it will "contribute to their efforts."

OceanGate CEO claimed sub was safer than scuba diving, texts show

A Las Vegas father and son told ABC News OceanGate CEO Stockton Rush pressured them for months into taking two seats on the now failed mission to the Titanic, making bold claims about the vessel's safety.

Financier Jay Bloom shared text messages between himself and Rush where Rush dismissed concerns from Bloom and his son Sean about taking the trip on the Titan submersible.

"While there's obviously a risk it's way safer than flying in a helicopter or even scuba diving," Rush texted.

"He sort of had this predisposition that it was safe," Bloom told ABC News. "And anybody who disagreed with him, he felt it was just a differing opinion."

Bloom added that Rush flew out to Las Vegas in a homebuilt plane to convince him to attend the voyage aboard the submersible.

"He flew it all the way to Vegas. And I was like, 'This guy is definitely down to take risk,'" Bloom said.

-ABC News' Sam Sweeney

Sub's carbon-fiber composite hull was the 'critical failure,' James Cameron says

Renowned Hollywood director and Titanic researcher James Cameron said he believes the carbon-fiber composite construction of the submersible's hull was the "critical failure" that led to its implosion during a deep-sea tour of the Titanic wreckage.

"You don't use composites for vessels that are seeing external pressure. They're great for internal pressure vessels like scuba tanks, for example, but they're terrible for external pressure," Cameron, who famously directed the Oscar-winning film "Titanic," told ABC News' George Stephanopoulos in an interview Friday on "Good Morning America."

"This was trying to apply aviation thinking to a deep-submergence engineering problem. We all said that it was, you know, a flawed idea and they didn't go through certification," he continued. "I think that was a critical failure.

"The thing that's insidious here," Cameron added, is the way these materials "fail at pressure."

"They fail over time, each dive adds more and more microscopic damage," he said. "So, yes, they operated the sub safely at Titanic last year and the year before, but it was only a matter of time before it caught up with them."

OceanGate CEO Stockton Rush, who was among the five crew members killed on the submersible, had previously defended the decision to manufacture the Titan with the material, saying he believed a sub made with carbon fiber would have a better strength-to-buoyancy ratio than titanium.

Bob Ballard, the oceanographer and explorer who discovered the Titanic wreckage in 1985, told ABC News that he expects the investigation into what happened "will go on for quite some time."

"There will be now a very systematic survey. I've done this before," he said during the interview Friday morning. "The [remotely operated vehicles] are going to do a very, very precise, systematic mapping that will collect the photography and high-definition imagery and they'll also be recovering the objects."