The Sub Pilot was a mercenary employed by Eli Mills. He and another man piloted Marine One into the Jurassic World lagoon in search of the Indominus rex. Throughout the mission, he remained in radio contact with Jack on the surface. As they entered the lagoon, he assured his nervous co-pilot that the Mosasaurus was probably long dead from starvation due (perceived) to a lack of food in the lagoon.
While his companion grabbed a piece of the I. rex ribs, the submarine pilot used a circular saw to cut it free, then sent it to the surface so it could be retrieved by Air One. However when trying to exit the paddock the Mosasaurus appeared and ate the submarine whole, having survived all this time despite the sub pilot's confident reassurances. Both men were killed.