Inspired by the recent DARPA call, two teams of MSc Unmanned Vehicle Systems Design (UVSD) Students at the University of Southampton have been developing systems that could be deployed for up to six months in the littoral zones of the world at depths of up to 50 m. Inside the pods are Quadrotor UAVs which can carry various sensor payloads and can perform automated surveys of their target areas.
Recent tests have been conducted in the Royal Navy Submarine Escape Training Tower (SETT) facility in Gosport. Sea Trials were completed in mid-July 2014: http://youtu.be/008VJd0c6lE