The announcement, called "Falling Up", cites cost and complexity that limits the Navy from operating over vast areas.

That makes a lot of sense, considering the cost of ships, which are expensive and limited in scope -- keep going up.

And as the technology of unmanned systems has been realized in Iraq & Afghanistan with the use of drones, the Navy wants to get in on the action.

The concept of DARPA's Upward Falling Payloads (UFP) would be "deployable, unmanned, distributed systems that lie on the deep-ocean floor in special containers for years at a time."