How Deep-Sea 'Titanic' Trip Became a Nightmare After Wealthy Adventurers' Submersible Disappeared

Rescuers are racing against the clock to try to find five people onboard the 'Titan,' a submersible that vanished Sunday

How could an excursion for five thrill-seekers heading to see the wreckage of the Titanic on a cutting-edge submersible — with a reported price tag of $250,000 per seat — turn into a nightmare?

Rescuers are racing against the clock to try to find five people onboard the Titan, a submersible that disappeared Sunday after a planned 7-to-9-hour trip down to view the wreckage of the Titanic.

It comes down to basics, Butch Hendrick, founder of Lifeguard Systems, which developed rescue procedures for surface and underwater rescues, tells PEOPLE. Hendrick, who was not involved in the development of the Titan, has trained thousands of divers and water rescuers for more than 50 years in more than 15 countries.

Related: Banging Sounds in 30-Minute Intervals Heard During Search for Missing 'Titan' Submersible: Report

“It has no real emergency systems on it,” Hendrick says. “It is supposed to self-surface, but if it’s flooded or entangled, none of those are going to work. There’s no emergency beacons that would automatically go on and signal our Coast Guard. It’s an unknown search.”

Although the watercraft is referred to as a submarine, it’s actually a submersible. A submarine has power, while a submersible does not. The OceanGate vessel Titan was dropped into the water on Sunday by its support vessel — the Canadian research icebreaker Polar Prince — to travel nearly 13,000 feet down to the shipwreck site off the coast of Newfoundland.

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It was to descend to the ocean floor and propel around the wreckage for a few hours before dropping the ballast and returning to the surface to be picked up by ship. Instead, the support vessel lost contact with Titan about an hour and 45 minutes into its descent.

The company Action Activation has confirmed that British billionaire Hamish Harding, who serves as its chairman, is one of the passengers aboard the submersible. Pakistani-British businessman Shahzada Dawood and his son Suleman Dawood are also on board the sub, PEOPLE has confirmed.

OceanGate CEO Stockton Rush and Titanic expert Paul-Henry Nargeolet were the other two passengers, according to the New York Times, ITV and the BBC.

Rush told The Associated Press in June 2021 that the Titan’s technology was “very cutting edge” and was developed with the help of NASA and aerospace manufacturers. “This is the only submersible — crewed submersible — that’s made of carbon fiber and titanium,” Rush said, per the AP, calling it the “largest carbon fiber structure that we know of,” with 5-inch-thick carbon fiber and 3.25-inch-thick titanium.

Related: Who Is on the Missing 'Titanic'-Bound Sub? All About the Passengers

But according to the New York Times, in 2018, leaders in the submersible craft industry were so worried about what they called the “experiment” approach of OceanGate that more than three dozen of them signed a letter to the company warning of  possible “catastrophic” problems with the submersible.

According to legal documents obtained by The New Republic, in 2018, a submersible pilot voiced concerns about the safely of the sub.

Trips to the Titanic site have been going on for years, but OceanGate opened up a tourist opportunity for those with the money to spend on the risky submersible treks.

Snugly fitting five on the floor of the sub, the time frame for oxygen onboard the vessel is set at about 96 total hours, but Hendricks’ believes the oxygen could possibly run out sooner.

“So we take five people, put them inside this submersible that is having problems, just the anxiety alone will reduce that time window because the respiratory rates will go up and their use of oxygen [too],” Hendrick says.

The first thought was that perhaps the Titan had popped up on the surface, far away from the ship. But Hendrick says he believes if that was the case, it would have been spotted by now.

“They have spent well over 50 hours with fixed wing aircraft, military pilots who are trained to search for the small body of a human, and this thing is 21-22 feet long, so if it was on the surface they would have found it,” Hendrick says.

Related: Admiral Leading 'Titan' Submersible Mission Says Unidentified Noise is ‘Target’ for Search

The Titan could also be entangled on the bottom of the ocean floor, or it may have flooded after an integral leak. If it is drifting midwater, it could also be very difficult to find. Some have speculated that the Titan may have imploded, something Hendricks says is entirely possible as well.

“If the integrity of the outside hull suddenly gave out, it would have imploded,” Hendrick says. “But it could have simply flooded inside from a small leak. Once the salt water entered it, if it hits the electrical system it rapidly becomes its own ground.”

Hendrick believes there may still be time to save the people inside, but it would be a miracle. The hatch is battened down with bolts that lock into the main gate, which must be opened before the people onboard could be released — and this would have to occur from the outside.

"…The chances we could find it, get it to the surface and get them out alive is very slim at this point. But we still have to stay positive,” Hendricks says.

In a statement released Tuesday, OceanGate said, “For some time, we have been unable to establish communications with one of our submersible exploration vehicles which is currently visiting the wreck site of the Titanic. Our entire focus is on the wellbeing of the crew and every step possible is being taken to bring the five crew members back safely. We are deeply grateful for the urgent and extensive assistance we are receiving from multiple government agencies and deep-sea companies as we seek to reestablish contact with the submersible. We pray for the safe return of the crew and passengers, and we will provide updates as they are available.”

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