Game-based training offers great potential for providing low-cost training systems for learning cognitive and procedural skills within the U.S. Navy. We introduce an effort, sponsored by the Office of Naval Research, to harness, apply and harden this capability by creating validated training games for the Navy. Over the period of fourteen months, our multi-disciplinary team collaborated to develop and validate a flooding control training game to help students at the U.S. Navy Recruit Training Command (RTC) learn to be better sailors. The Flooding Control Trainer (FCT) provides individual training within the simulated interior of an Arleigh-Burke class destroyer. The trainer reinforces damage control skills that the recruits have been exposed to in lectures, but which they have not had a chance to practice in context. In developing the trainer, we focused on both the specific application domain as well as the design methods required to ensure that the trainer was based on relevant learning objectives, incorporated a strong narrative, used an instructional strategy and a game play style that were complementary, and contained embedded assessment capabilities. The FCT is based on the open-source Delta3D engine. To support effective training, we augmented the engine with a task-based instructional infrastructure and a variety of feedback mechanisms, including real-time guidance and feedback as well as after-action debrief. We conducted several empirical tests of the product, including a usability study and a learning validation study using the target recruit population as subjects. The results indicate that the FCT is usable, well-received by recruits and produces a significant improvement in performance across a range of cognitive and procedural skills, including situational awareness, communications, navigation and decision-making. We present our approach, describe the training game design, discuss the studies conducted and their results, and discuss next steps to create Navy training games for use beyond RTC.