CIWS
Close-In Weapon System
Close-In Weapon System is an automated shipboard defense system designed to detect and destroy incoming anti-ship missiles and aircraft at short range as a last line of defense.
The Close-In Weapon System (CIWS) is a ship's final layer of defense against incoming anti-ship missiles that have penetrated all other defensive measures. The most widely deployed CIWS is the Phalanx, a radar-guided 20mm Gatling gun capable of firing 4,500 rounds per minute. The system operates autonomously, its radar detects, tracks, and engages threats without human intervention, a necessity given the extremely short reaction times involved when an anti-ship missile is seconds from impact.
The Phalanx uses a closed-loop tracking system where the same radar that tracks the incoming missile also tracks the outgoing stream of bullets, automatically correcting aim in real time. This "bullet hose" approach creates a wall of tungsten projectiles in the path of the incoming missile. The system can engage targets from about 1.5 kilometers away, giving it only seconds to destroy a supersonic missile.
As anti-ship missiles have grown faster and more maneuverable, CIWS technology has evolved. The SeaRAM system replaces the Phalanx gun with a launcher for Rolling Airframe Missiles, offering greater range and effectiveness against advanced threats. Other nations have developed their own CIWS solutions, including Russia's Kashtan and the Netherlands' Goalkeeper, each optimized for their respective threat environments.
Related Terms
Anti-Ship Missile
A guided weapon designed to strike and damage or sink naval vessels, using radar, infrared, or satellite guidance to find and engage targets at sea.
Carrier Strike Group
A naval formation centered on an aircraft carrier, typically including guided-missile cruisers, destroyers, a submarine, and a supply ship, capable of projecting power anywhere on the globe.
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