Read for instance BBC
Harrison Okene, 29, was on board the tug boat Jascon-4 when it capsized in heavy swells.
It sank to the seabed, upside down, but Mr Harrison was trapped in an air pocket and able to breathe. […]
“I was there in the water in total darkness just thinking it’s the end. I kept thinking the water was going to fill up the room but it did not,” he said.
“I was so hungry but mostly so, so thirsty. The salt water took the skin off my tongue.”
“I could perceive the dead bodies of my crew were nearby. I could smell them. The fish came in and began eating the bodies. I could hear the sound.”
But after 60 hours, Mr Harrison heard the sound of knocking.