The Fleet Rehabilitation and Modernization (FRAM) program of the United States Navy might be considered the beginning of the final phase in the shift of mission for destroyers from a surface attack role to that of a submarine hunter. The United States Navy (USN) is the branch of the United States armed forces responsible for naval operations. ... USS Lassen, an Arleigh Burke-class destroyer In naval terminology, a destroyer is a fast and manouverable yet long-endurance warship intended to escort larger vessels in a fleet or battle group and defend them against smaller, short-range attackers (originally torpedo boats, later submarines and aircraft). ... USS Los Angeles A submarine is a specialized watercraft that can operate underwater. ...

The ships received a larger combat information center (CIC) and sonar control as well as an antisubmarine rocket (ASROC) launcher, a torpedo magazine, and the 01-level afterdeck was converted to a hangar and helicopter flight deck to facilitate the use of drone antisubmarine helicopters (DASH). The new ASROC launcher was installed between the stacks in the space formerly held by the 21-inch torpedo tubes which, in turn, were replaced by two 15.5-inch triple torpedo tube mounts located in the waist at the after stack one to port and the other to starboard. The DASH flight deck and hangar replaced the after 5-inch double mount which reduced the main surface battery to four 5-inch/38-caliber guns in two twin mounts forward and the 40 mm and 20 mm gun mounts were removed. This modernization was designed to extend the life of the destroyer by at least eight years. A combat information center (CIC, or action information center) is the tactical center of a warship, manned and equipped to collect, present, manage, evaluate and disseminate information for the use of the embarked flag officer, commanding officer, and control agencies. ... The F70 type frigates (here, La Motte-Picquet) are fitted with VDS (Variable Depth Sonar) type DUBV43 or DUBV43C tugged sonars Sonar (sound navigation and ranging) is a technique that uses sound propagation under water to navigate or to detect other watercraft. ... An anti-submarine weapon is any weapon system designed for anti-submarine warfare (ASW), that is to attack and destroy enemy submarines and other underwater devices. ... An older Matchbox ASROC launcher, phased out in the 1990s ASROC (for Anti-Submarine Rocket) is an antisubmarine missile system, developed by the United States Navy, and installed on over 200 surface ships, generally cruisers and destroyers. ... A modern torpedo, historically called a self propelled torpedo, is a self-propelled guided projectile that (after being launched above or below the water surface) operates underwater and is designed to detonate on contact or in proximity to a target. ... An afterdeck is the part of a ships deck amidships towards the stern. ... Hangars can be used to hold airplanes, airships and helicopters. ... A helicopter is an aircraft which is lifted and propelled by one or more large horizontal rotors (propellers). ... The flight deck of an aircraft carrier is the surface from which its aircraft take off and land, essentially a miniature airfield at sea. ... Shadow 200 UAV flying over Iraq. ... Port is the nautical term (used on boats and ships) that refers to the left side of a ship, as perceived by a person facing towards the bow (the front of the vessel). ... Starboard is the nautical term (used on boats and ships) that refers to the right side of a vessel, as perceived by a person facing forward (i. ... In military science, a battery is a group of artillery cannons or rockets, so grouped in order to facilitate battlefield communication and the organization of barrages. ...