Theodore Taylor's own life experience probably had the most influence on this book. His father worked in shipyards so Taylor grew up around boats, which is where the first part of the story takes place. Phillip grows up in a harbor town around ships and he leaves for America on a ship which wrecks and lands him on raft. Taylor, growing up around ships and the water, probably knew quite a bit about both and could write based on that experience. He also attended a Merchant Marine Academy and served in the Navy so most of the first half of his life was spent in and around the ocean and ships. The story takes place in the midst of WWII and Taylor grew up during the war, so he knew about U-Boats and torpedoes because those were topics which were heavily reported on during that time.