A close-in weapon system (CIWS ) is a point-defense weapon system for detecting and destroying short-range incoming

missile A missile is an airborne ranged weapon capable of self-propelled flight aided usually by a propellant, jet engine or rocket motor. Historically, 'missile' referred to any projectile that is thrown, shot or propelled towards a target; this ...

s and enemy aircraft which have penetrated the outer defenses, typically mounted on a

naval A navy, naval force, military maritime fleet, war navy, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operatio ...

ship. Nearly all classes of larger modern

warship A warship or combatant ship is a naval ship that is used for naval warfare. Usually they belong to the navy branch of the armed forces of a nation, though they have also been operated by individuals, cooperatives and corporations. As well as b ...

s are equipped with some kind of CIWS device. There are two types of CIWS systems. A gun-based CIWS usually consists of a combination of

radar Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...

s, computers, and rapid-firing multiple-barrel

rotary cannon A rotary cannon, rotary autocannon, rotary gun or Gatling cannon, is any large-caliber multiple-barreled automatic firearm that uses a Gatling-type rotating barrel assembly to deliver a sustained saturational direct fire at much greater ra ...

s placed on a rotating

turret Turret may refer to: * Turret (architecture), a small tower that projects above the wall of a building * Gun turret, a mechanism of a projectile-firing weapon * Optical microscope#Objective turret (revolver or revolving nose piece), Objective turre ...

. Missile-based CIWSs use either

infra-red Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those of ...

passive radar Passive radar (also referred to as parasitic radar, passive coherent location, passive surveillance, and passive covert radar) is a class of radar systems that detect and track objects by processing reflections from non-cooperative sources of illu ...

/ ESM, or

semi-active radar Semi-active radar homing (SARH) is a common type of missile guidance system, perhaps the most common type for longer-range Air-to-air missile, air-to-air and surface-to-air missile systems. The name refers to the fact that the missile itself is o ...

terminal guidance In the field of weaponry, terminal guidance refers to any guidance system that is primarily or solely active during the "terminal phase", just before the weapon impacts its target. The term is generally used in reference to missile guidance syst ...

to guide missiles to the targeted enemy aircraft or other threats. In some cases, CIWS are used on land to protect military bases. In this case, the CIWS can also protect the base from shell and rocket fire.

Gun systems

A Phalanx CIWS and ASELSAN STOP on the fore-starboard side of TCG Anadolu

A gun-based CIWS usually consists of a combination of radars, computers and rotary or

revolver A revolver is a repeating handgun with at least one barrel and a revolving cylinder containing multiple chambers (each holding a single cartridge) for firing. Because most revolver models hold six cartridges before needing to be reloaded, ...

cannon placed on a rotating, automatically aimed gun mount. Examples of gun-based CIWS products in operation are: *

AK-630 The AK-630 is a Soviet Union, Soviet and Russian fully automatic naval, rotary cannon, close-in weapon system. The "630" designation refers to the weapon's six gun barrels and their 30 mm caliber. The system is mounted in an enclosed automatic ...

, 630M, 306, 630M1-2, and 630M2 - 30×165mm caliber * Aselsan GOKDENIZ and GOKDENIZ ER - 35×228mm * DARDO and Fast Forty - 40×365mmR * Denel 35mm Dual Purpose Gun - 35×228mm * Goalkeeper CIWS - 30×173mm *

Kashtan CIWS The Kortik (, "dirk") close-in weapon system (CIWS) is a modern naval air defence gun-missile system deployed by the Russian Navy. Its export version is known as Kashtan (, English: Chestnut), with the NATO designation CADS-N-1 Kashtan. The Korti ...

and M variant - 30×165mm * Mauser BK-27 - 27×145mm *

Meroka CIWS The Meroka CIWS is a Spanish Navy 12 barrelled 20 mm close-in weapon system (CIWS), using twelve Oerlikon Contraves, Oerlikon 20 mm/12 guns mounted in 2 rows of 6 guns each. The system's primary purpose is defence against anti-ship mis ...

- 20×128mm *

Myriad CIWS Myriad CIWS was a twin 7 gun barrel, barrelled, 25 mm rotary cannon-style CIWS developed by a consortium including OTO Melara. The system's primary purpose, had it ever gone into production, would have been defense against anti-ship missiles, ...

- 25×184mm * PIT-Radwar OSU-35K - 35×228mm *

Rheinmetall Oerlikon Millennium Gun The Rheinmetall Oerlikon Millennium Gun or Rheinmetall GDM-008 is a close-in weapon system designed by Rheinmetall Air Defence AG (formerly known as Oerlikon Contraves) for mounting on ships. It is based on the 35/1000 revolver gun land-based a ...

- 35×228mm *

Rheinmetall Sea Snake 30 mm The Rheinmetall Sea Snake 30 mm is a close-in weapon system designed by Rheinmetall Air Defence AG for mounting on ships. It is based on the KCE30 30 mm revolver cannon, and was designed by a request of the German Navy. It is capable of employ ...

- 30×173mm *

Phalanx CIWS The Phalanx CIWS () is an automated gun-based close-in weapon system to defend military watercraft automatically against incoming threats such as aircraft, missiles, and small boats. It was designed and manufactured by the General Dynamics Co ...

Block 0, 1, 1A, and 1B - 20×102mm *

Sea Zenith Sea Zenith is a four-barrelled 25 mm CIWS used by the Turkish Navy on their MEKO 200 frigates, like the Barbaros and Yavuz classes. It was developed in the 1980s by Oerlikon Contraves ( Rheinmetall Air Defence since 2009) around their O ...

- 25×184mm * H/PJ-76A - 37×240mm * Type 730 and

Type 1130 The Type 730 is a Chinese seven-barrelled 30 mm Rotary cannon, Gatling gun/rotary cannon CIWS. It has a PLA Navy designation H/PJ12. It is mounted in an enclosed automatic turret and directed by radar, and electro-optical tracking systems. ...

CIWS - 30×165mm * Pantsir-M - 30×165mm

Limitations of gun systems

CIWS systems are short range: the maximum effective range of gun systems is about ; systems with lighter projectiles have even shorter range. The expected real-world kill-distance of an incoming anti-ship missile is about or less, still close enough to cause damage to the ship's sensor or communication arrays, or to wound or kill exposed personnel. Thus some CIWS like Russian Kashtan and Pantsir systems are augmented by installing the close range

surface-to-air missile A surface-to-air missile (SAM), also known as a ground-to-air missile (GTAM) or surface-to-air guided weapon (SAGW), is a missile designed to be launched from the ground or the sea to destroy aircraft or other missiles. It is one type of anti-ai ...

s on the same mounting for increased tactical flexibility. They have a limited kill probability compared to other antiair guns. Even if the missile is hit and damaged, this may not be enough to destroy it entirely or to alter its course. Even in the case of a direct hit, the missile or fragments from it may still impact the intended target, particularly if the final interception distance is short. This is especially true if the gun fires kinetic-energy-only projectiles.

Comparison table

Missile systems

A missile-based CIWS comprises a combination of radars and computers connected to either a rotating, automatically aimed launcher mount or

vertical launching system A vertical launching system (VLS) is an advanced system for holding and firing missiles on mobile naval platforms, such as surface ships and submarines. Each vertical launch system consists of a number of ''cells'', which can hold one or mo ...

. Examples of missile-based CIWS in operational service are: * 9M337 Sosna-R * HQ-10 / FL-3000N * Pantsir-M missile system * RIM-116 Rolling Airframe Missile * Sea Oryx *

Tor missile system The Tor (; ) is an all-weather, low-to medium-altitude, short-range surface-to-air missile system designed for destroying airplanes, helicopters, cruise missiles, unmanned aerial vehicles and short-range external ballistics, ballistic threats ( ...

Land-based

CIWS are also used on land in the form of Pantsir and C-RAM. On a smaller scale, ''

active protection system An active protection system (APS) is a system designed to actively prevent certain anti-tank weapons from destroying a vehicle. Countermeasures that either conceal the vehicle from or disrupt the guidance of an incoming guided missile threat are ...

s'' are used in some

tank A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and battlefield mobility provided by tracks and a powerful engine; ...

s (to destroy rocket propelled grenades (RPGs), and several are in development. The Drozd system was deployed on Soviet Naval Infantry tanks in the early 1980s, but later replaced by explosive reactive armour. Other systems that are available or under development are the Russian

Arena An arena is a large enclosed venue, often circular or oval-shaped, designed to showcase theatre, Music, musical performances or Sport, sporting events. It comprises a large open space surrounded on most or all sides by tiered seating for specta ...

, Israeli

Trophy A trophy is a tangible, decorative item used to remind of a specific achievement, serving as recognition or evidence of merit. Trophies are most commonly awarded for sports, sporting events, ranging from youth sports to professional level athlet ...

, American Quick Kill and South African-Swedish LEDS-150.

Laser systems

Laser-based CIWS systems are being researched. In August 2014 an operational prototype was deployed to the Persian Gulf aboard . The

Scientific and Technological Research Council of Turkey The Scientific and Technological Research Institution of Turkey (, TÜBİTAK) is a national agency of Turkey whose stated goal is to develop "science, technology and innovation" (STI) policies, support and conduct research and development, and to ...

( Turkish: ''Türkiye Bilimsel ve Teknolojik Araştırma Kurumu'', TÜBİTAK) is the second organisation after the US to have developed and tested a High Power Laser CIWS prototype System which is intended to be used on the TF-2000 class frigate and on Turkish airborne systems.

References

{{commons category, Close-in weapon system * Anti-aircraft guns Naval anti-aircraft guns Naval surface-to-air missiles Weapons countermeasures