Best- and worse-case scenarios for the lost vessel

The tourist submersible that went missing over the weekend on an expedition to the Titanic may have gotten stuck on the century-old sunken ship’s wreckage or be bobbing undetected in the Atlantic Ocean — unless it met a worse fate and imploded on its journey, experts say.

Titanic expedition leader G. Michael Harris said he feared tragedy had struck the lost submersible and that there was nothing the Navy could do to save its five passengers — three of whom he said he knows personally.

“Worst situation is something happened to the hull. Our fear is that it imploded at around 3,200 meters,” Harris told Fox News. 

When asked if there was something the Navy could do Harris shook his head to say “no.”

“I don’t see anything that can happen at this point. I’m trying to be somewhat cautious, I don’t want to be the naysayer of what’s going on. When you’re talking 6,000 pounds per square inch, it is a dangerous environment,” Harris said.

Harris noted that very few people have trekked as deep into the ocean as the Titanic’s wreckage — which sits nearly 13,000 feet (2.4 miles) below sea level.

“More people have been to outer space than to this depth of the ocean. When you’re diving in these situations, you have to cross your t’s, dot your i’s. You have to do everything absolutely perfect and by the book.”

Rear Admiral John Mauger, who is overseeing the search and rescue mission for the missing submarine, said that it’s also possible that the vessel could be trapped in the Titanic, which lies about 370 miles off the coast of Newfoundland, Canada.

“We don’t have equipment onsite that can do a survey of the bottom,” Mauger told The Mirror. “There is a lot of debris so locating it will be difficult. Right now, we’re focused on trying to locate it.”

Michael Guillen, a former ABC science editor, said that the terrifying scenario would not be the first time that’s happened on an expedition to the deep-sea wreck.

He recalled how he had gone on a trip to the Titanic on the Mir 1 submersible in 2000 when the vessel encountered a strong underwater current that propelled them into the storied ship, where it got stuck under the stern.

“When we collided with the propeller, and I started seeing those big chunks of metal raining down on us … the first reaction I had was, ‘This can’t be happening,’” he told ABC News on Tuesday.

“This voice came into my head and said, you know, ‘This is how it’s going to end for you,’” he recalled. “I’ll never forget those words.”

Guillen said that he feared that he would die, but a team managed to maneuver the submersible free and navigate it back to the surface.

“I’m very aware of what these poor souls on board the ship the Titan are experiencing,” he said. “I am just heartbroken about it.”

The Coast Guard on Tuesday said they also have hope that the missing sub is bobbing undetected somewhere in the vast waters.

“If it’s on the surface, we’re fairly sure we’re going to be able to find it,” Capt. Jamie Frederick said, noting that there had been fog in the area where the sub was lost, but visibility was improving Tuesday.

OceanGate Expeditions, a private company that provides tours for the Titanic wreckage site for as much as $250,000, confirmed that their new sub had gone missing with five crew members.

Its passengers included British billionaire Hamish Harding, Pakistani businessman Shanzada Dawood and his 19-year-old son Sulaiman, French deep diver Paul-Henri Nargeolet and OceanGate CEO Stockton Rush.

The 21-foot-long craft submerged Sunday about 400 miles south of St. John’s, Newfoundland, before losing contact with its mothership, the Polar Prince, an hour and 45 minutes later.

Even though the submarine lost contact at about 9:45 a.m., it wasn’t reported missing to the US Coast Guard until 5:40 p.m. — eight hours later.

Oceangate Expeditions said the vessel had up to 96 hours of “life support” in emergency oxygen after it first went missing. By Tuesday afternoon, US Coast Guard officials said there was likely only 41 hours of oxygen remaining.

The ongoing search operation is focused on an area about 900 miles off the coast of Cape Cod at a depth of nearly 13,000 feet — making it the deepest-ever rescue mission in history if successful.

Experts, however, have cautioned that few craft can reach that depth and even if they could, it’s incredibly unlikely they could attach to the submersible and pull it up to the ocean’s surface.

A submersible, unlike a submarine, does not have enough power to launch itself into the ocean and return on its own, meaning a support ship must launch and recover it.

“Throw in a bunch of tourists in a new sub, which was just created in the last couple of years,” Harris said. “It’s not looking good.”