Books in the Corps of Discovery series

Bill Clark realizes he's not on Earth anymore when his plane crash lands 10,000 miles from help on an unexplored, uninhabited planet. Uninhabited by homo sapiens, that is. It seems most of the inhabitants are hungry predators straight out of the Ice Age.With no hope of rescue, Bill and his fellow survivors have to rely on all their training, skills, and quick reactions to stay alive. And that's just the first week!