what happened on 2nd jan in chapter 3

A torrent of green and white water broke over the ship and the narrator's head smashed into the wheel. He became aware of flying overboard and sinking below the waves. The narrator had by then accepted the certainty of his death and was beginning to lose consciousness. He felt quite peaceful in his resignation. But his head popped out of the water and he saw the Wavewalker was capsizing with her masts almost horizontal. Then a wave hurled her upright and his lifeline jerked taut, he grabbed the guard rails and sailed through the air into the Wavewalker's boom. Subsequent waves tossed him around the deck like a rag doll. His ribs had cracked, his mouth was filled with blood and broken teeth but he managed to find the wheel, line up the stern for the next wave and hang on.