I know its russian defense forum. But guys you seriously don't keep an eye on US latest happenings . DARPA's Unmanned Submarine Stalker Could Change Naval Warfare Forever
ACTUV concept, a possible solution for persistently tracking enemy submarines, especially the diesel AIP kind, with maximum affordability in mind.
Meet The Sea Hunter:
Sea Hunter will be a trimaran design, with the vast majority of its hull and superstructure built of lightweight and radar-translucent carbon-composite materials. It will have a length of around 130 feet and its center hull will be long and streamlined. The trimaran design lends itself to endurance, sea keeping, and speed, which will be necessary for keeping up with sprinting diesel submarines as well as those that are running slow and quiet for long periods of time. The first ACTUV prototype, named Sea Hunter, is currently under construction at Oregon Iron Works and will be tested on the Columbia River later this year. Oregon Iron Works have become something of a Scaled Composites-like boutique manufacturing house for exotic, experimental and stealthy naval vessels.
The unmanned, unarmed, and highly autonomous ship's design is largely based around a series of plug-and-play modular components, allowing the vessel to be reconfigured for different missions with relative ease. Periphery sensors will include multiple types of radar, electro-opitcal systems for viewing the ship's surroundings in day and night, and electronic support measures used to sniff out enemy radio and sensor transmissions. The Sea Hunter's most potent sensors will be its mid-frequency sonar, built into a bulbous enclosure that juts out below the ship's keel, used for locating undersea targets at longer ranges while its high-frequency active sonars, mounted in small protrusions below its main hull, will better refine tracking and make it extremely hard for the object being pursued to slip away. These high-frequency sonar systems will also be able take a synthetic 'picture' of the sub's target so that Sea Hunter's computers can help classify and identify it by comparing the target to images and sound signatures stored in its memory banks. From there, on-board automation helps predict what the target will do next and will send updates to controllers thousands of miles away when the target does something of significance or when it observes something in its area worth noting.