Autonomous underwater vehicles are described that are stackable with other like autonomous underwater vehicles on a suitable launch platform, such as within a vertical missile launch tube of a submarine, waiting to be deployed into the water. The underwater vehicles can be deployed or launched individually, in groups, or all together into the water. While stacked together, the stacked autonomous underwater vehicles can connect to one another or to external structure of the launch platform. In addition, the underwater vehicles can be positively buoyant or can be made to have controllable buoyancy to allow the underwater vehicles to float up and out of the launch platform during deployment without an external deployment force.