Controlling a robotic submersible 10 km below the ocean surface is not some trivial task. Water is not exactly translucent to
What do you think will be the preferred form of communication between this UUV and it's oceanographic mothership? Could it have been ELF communication, or a dipping sonar that emits a direct beam SASER (sonic equivalent of laser using phonons instead of photons) in the terahertz range, or perhaps both? It should be noted that the US Navy shutdown the last of it's ELF communication facilities back in 2004, which means their ability they could intercept ELF comms between motherships and their UUV's would be slim. I'm guessing the motherships could use ELF comms to track their UUV, a dipping sonar SASER to directly guide the UUV, and perhaps a backup seafloor bed inertial guidance integration in the drone.
There is no indication that I am aware of as to the nature of the communication solution. I think the primary mode will be autonomous
"cruise missile" travel with a dynamic bathymetry assessment system. They cannot feed high resolution bathymetry data into any drone
since such data does not exist. So the drone has to scan the topography and is also useful for mapping it. As for communication
to the "mothership" your ideas are as good as mine. I think there will be communications pods lowered to some depth (3 km?) at
certain locations that can be used to interact with the drone. Maybe it will also come to the surface like a submarine. But pods
allow the drone to stay hidden. It may well be that the pods are another class of drone that also travels at "mid depth" and forms
part of a layered communication infrastructure. As long as the enemy does not know where you are, then it is OK.