And so the story goes that...
"In Yevamoth 121a, Rabbi Gamliel related, “I was once traveling on board a ship when l observed a shipwreck and was sorely grieved for the apparent loss of a scholar who had been traveling on board that ship. (And who was he? — Rabbi Akiva.) When I subsequently landed, he came to me and sat down and discussed matters of halacha. ‘My son,’ I asked him, ‘who rescued you?’ ‘The plank of a ship,’ he answered me, ‘came my way, and to every wave that approached me I bent my head.’” (http://www.thejewishweek.com/editorial_opinion/letters/talmudic_surfer)