An archive image of the interior of the submersible.OCEAN GATE

It’s a race against time. Search teams from the mysteriously missing submarine in Atlantic waters, with five people on board, they have the hours counted to find them. Because the little ‘Titan’, from the Ocean Gate company, He had only 96 hours of oxygen supplies, or four days. And they are exhausted. The expedition left Newfoundland, Canada, last Sunday.

The Pisces III was trapped on the seabed 480 meters deep, off Ireland, also in the Atlantic. The Titan was heading towards the remains of the Titanic, which lie about 3,800 meters below the surface. It is designed to be submerged up to 4,000 meters deep, as the company explains on its website.. It is the deepest of the three submersibles that Ocean Gate has.

on board of Pisces III only two people traveled: Pilot Roger Chapman, 28, former Royal Navy submariner, and engineer and pilot Roger Mallinson, 35. His mission was work and routine: laying telephone cables on the seabed.

But they had an accident and they spent three days trapped in the small submersible. When they were rescued alive, they had only 12 minutes of oxygen left.. How have they managed to survive so far?

Dwindling oxygen supplies: every hour counts

On August 29, 1973, Chapman and Mallinson began the dive with a full oxygen tank. And they knew that, as important as their cable-laying job, it was take care of the life support in the submersible. For that, as the two recall in this BBC report, every 40 minutes they turned on a lithium hydroxide fan to absorb the carbon dioxide (CO2) they exhaled. Then they injected a small amount of oxygen.

But when they finished their work and started the return to the mothership, the submersible struck and sank. dropped, at 65 kilometers per hour, to the seabed. When they realized they were alive, the two crew members made contact with the base and They began to organize themselves to survive.

The submarine had 72 hours of oxygen in the event of an accident. That is, oxygen for three days. But they had already used up eight hours in the immersion They had 66 left.

In the case of titan submarinewe remember, they wear oxygen reserves for 96 hours and five people. But the days pass and every hour counts. The submarine lost contact on Sunday, 1h45 after its dive.as the US Coast Guard explains. That’s when they’re estimated to have 96 hours of battery life. This Tuesday, the coastguard warned that the submarine had “about 40 hours of breathable air” left.

Does not speak, does not move, very cold and headache

the first thing they did Chapman and Mallinson was to shut down the electrical systems and turn everything off. Did you know, to conserve oxygen, the less physical exertion the better. “If you turn everything off, you use a quarter of the oxygen. You don’t talk or move”, they explain on the BBC. Moreover, the two men they positioned themselves as high as possible in the submarinebecause they explain that the stale and heavy air settles down, at the bottom.

We are talking about a cabin 6 meters long, very small, so they had very little space. It should be taken into account that the dimensions of the Titan are almost the same (6.70), but three more people are in it.

Mallinson recalls on the BBC that they they barely spoke. “We just held hands and hugged each other to show we were okay. It was very cold, we were wet. It’s amazing how intensely cold you can feel.”. and they started to suffer severe headaches, because they lacked oxygen. “But our job was to stay alive“, they remember.

So is that of The Titans crew. All however, they signed a document, before the expedition, in which they clearly accepted that they risked dying.

Sign that you accept death accordingly

What the document you sign before you travel on the commercial submersible Titan says is exactly this: “A trip on an experimental submersible device, not approved by a regulatory body, which may result in physical harm, disability, emotional trauma or death.”. We see it in this video, shared on Twitter by CNN contributor Frida Ghitis.

“The word ‘death’ is mentioned three times on the first page of the document, we never get it out of our heads”remember the writer Mike Reiss in statements to the BBC. “You sign a disclaimer that lists one after another the ways you could die on the trip,” he explains. Reiss made the same trip last year. “You know exactly what you’re getting into,” he says.

CBS correspondent David Pogue also traveled last year.. Speaking to BBC’s ‘The Context’ programme, Pogue explains that the submarine has up to seven different functions to get it back to the surface and that it is “really worrying” that none of them have worked so far.

and warns that returning to the surface is the only option. If the sub had been caught in something or had no chance to maneuver, there would have been none. “There is no save, there is no escape pod. You must rise to the surface or die.”

The same warns Reiss. “If it’s in the background, I don’t know how anyone will be able to access it.much less bring it back.”

Oxygen running out: how to prolong it?

The fact is that these hours are crucial. And by the way, the five people trapped inside may experience something similar to what Chapman and Mallinson experienced. Oxygen dosing was key in his case, and it can be now too.

The oceanographer explains it Eugenio Fraile, of the IEO, in statements to the Cuatro program “Everything is a lie”. The Titan “disappeared Sunday at 9:00 p.m.”, so “it’s the first day, it would still have 3 days of survival left”. If they had about 40 hours left this Tuesday afternoon, according to the U.S. Coast Guard, Today, they have oxygen left for a little over a day.

Chapman and Mallinson had a 72-hour oxygen supply, but they managed to lengthen them much more. As? Because they decided to let the carbon dioxide build up in the sub a bit longer, beyond the stipulated 40 minutes, in order to retain more oxygen. This This caused lethargy and drowsiness. When they were rescued, the Britons had been inside for 84.5 hours. “We had 72 hours of life support when we started diving, so we managed to last another 12.5 hours“recalls Chapman on the BBC.

But oxygen is not the only thing. Fraile also mentions another important factor: the cold, the temperature at which they are. “We are talking about the fact that they are at a depth of 3,800 meters and at this depth, ocean water is about 2 degrees.

Under these conditions, it is also likely that they will not carry many provisions on the Titan. It is not common. “They don’t usually take a lot of food on board, as the dives are usually relatively short, 8 or 12 hours”Brother explains.

Neither optimism nor security

Neither Reiss, nor Pogue, nor Fraile are very optimistic about the outcome of this expedition. Reiss confesses that he himself thought he might die when he did his senior year. “When I got into the submarine, I thought to myself that this could be the end.” “No one can be caught off guard,” acknowledges the writer. “It’s not the holidaysnor a search for emotions,” he explains. “It’s exploration, they’re explorers.”

As an oceanographer, Fraile warns that ‘any action at sea is really complex’, and if it is under the sea, even more. “Every little thing we want to do on the surface of the ocean, Under the sea it is complicated 4, 5 and 6 times more”.

And moreover, he explains that in the case of these commercial submarines that do these types of expeditions, the security is not the same than in normal submarines. “Their security systems are totally different.” And also warns that “The people on board are rich who want inaccessible tourism. On many occasions, being able to reach a place no one has been is better than your own safety. These are not conditions for putting someone overboard”.

The GPS does not work underwater, nor the radio, which means there is “no way” to communicate with the vessel, And this is what complicates everything the most: don’t even know where they are. “He’s looking for a needle in a haystack. It doesn’t look good at all,” Fraile concludes.