Goalkeeper CIWS

Goalkeeper is a Dutch close-in weapon system (CIWS) introduced in 1979 and in use. It is an autonomous and completely automatic weapon system for short-range defense of ships against highly maneuverable missiles, aircraft and fast maneuvering surface vessels. Once activated the system automatically performs the entire process from surveillance and detection to destruction, including selection of the next priority target.

Development
Development of the system began in 1975 with Holland-Signaal (now Thales Nederland) working with General Dynamics, which supplied the GAU-8 gun. A prototype, the EX-83 was first demonstrated to the Royal Netherlands Navy in 1979.

In 2012 the Dutch ministry of defense announced that the Goalkeeper systems in use by the Netherlands Navy will receive radar upgrades, mechanical improvements, new high-precision frangible ammunition and a new electro-optical tracking system. Also the system's surface mode will be improved to counter high speed boats and fast attack craft. These upgrades will make the system more capable to defend ships against the latest threats such as modern anti-ship missiles, more effective in littoral environments and less vulnerable to malfunctions. It also expands the life of the system to at least 2025. The first of 16 systems will be upgraded and tested by Thales Nederland, the others at the naval base in Den Helder.

Target selection
Goalkeeper has two radar sub-systems, one to find threats and another to track and engage them, which operate together to identify and prioritise targets, and engage the highest priority one.

The 2D I band search radar, which can handle up to 18 targets at once, generates a threat picture which the gun system uses to identify and prioritize threats. The system has identify friend or foe (IFF) functionality to rule out friendly traces. The tracking radar operates in both I band and K band to enable quick acquisition on the threat bearing. Data from both the I band and K band return signals indicate target range and can be used to identify, and respond to the use of, electronic countermeasures (ECM). The dual band system also reduces the effect of clutter, which can mask the target at low altitude. A camera system on the assembly provides a visual fallback for the system operator.



Target engagement
The GAU-8/A Avenger 30 mm Gatling gun, as used by the A-10 Thunderbolt II aircraft, was selected for the system. The 30 mm round has a greater mass than the M61 Vulcan used in the Phalanx CIWS, so it provides much greater destructive power with similar muzzle velocity and range.

The 30 mm round has a discarding nylon sleeve (sabot) with a 21 mm sub-calibre tungsten penetrator. The nylon sabot provides a seal between penetrator and barrel, and reduces wear.

The tracking radar is capable of monitoring the line of fire and commanding minor adjustments.

Supersonic missiles that are damaged may still have enough momentum to hit the ship—the only way to ensure the protection of the ship is either to detonate the warhead of the missile or obliterate the missile.

The system's reaction time to a Mach 2 sea-skimming missile such as the Russian SS-N-22 Sunburn from automatic detection to kill is reported to be 5.5 seconds with the firing synchronized to start the engagement at a range of 1,500 m and ending with a kill at 300 m.

Operational History
Goalkeeper’s capabilities have been proven many times during sea-going trials. During live-fire exercises, multiple different targets including Harpoons, Exocets and target drones were shot down by Goalkeeper. During anti-piracy operations off the coast of Somalia the system destroyed several pirate boats and skiffs that had been seized by the Netherlands Navy.

Specifications

 * Gun: GAU-8/A Avenger 30 mm seven-barrel Gatling gun.
 * Height: 3.71 m (above deck) 6.2 m (including deck penetration).
 * Weight: 6,372 kg with 1,190 rds of ammunition (above deck), 9,902 kg (total).
 * Elevation +85° to −25° at 80°/s.
 * Muzzle velocity: 1,109 m/s (MPDS round).
 * Turret speed 360° in 3.8 seconds
 * Rate of fire: 70 rounds/second (4,200 rounds/minute).
 * Maximum burst size: 1,000 rounds.
 * Ammunition: 1,190 linkless (HEI, API, TP, MPDS, FMPDS) rounds in a below-deck magazine.
 * Reload time: 9 minutes (loading is done below deck)
 * Weapons range: 350 to between 1,500 and 2,000 meters dependent on ammunition.
 * Search radar: I band/linear array. I band is X band. Beamsize 1.5 degrees horizontal, 60 degrees vertical. Rotates at 1 Hz (60 RPM). Range approx. 30 km.
 * Engagement radar: I band and K band monopulse cassegrain.
 * Optical system: TV (Future EO/IR)
 * 100% kill distance: 500 m

Operators

 * 🇬🇧 United Kingdom: Royal Navy
 * HMS Illustrious (R06), HMS Bulwark (L15), HMS Albion (L14) (Will be retired from the Royal Navy in 2015)
 * 🇨🇱 Chile: Chilean Navy
 * 2 Jacob van Heemskerck-class frigates
 * 🇳🇱 Netherlands: Royal Netherlands Navy
 * 4 De Zeven Provincien class air-defence frigates, 1 Goalkeeper per ship, full provisions for second system, only HNLMS Evertsen has two Goalkeepers.
 * 2 Karel Doorman class frigates, 1 Goalkeeper per ship
 * 2 Rotterdam class amphibious transport docks, 2 Goalkeepers per ship
 * 1 Karel Doorman class support ship, 2 Goalkeepers (in service 2015)
 * 1 HNLMS Amsterdam Replenishment oiler, 1 Goalkeeper, decommissioned in 2015
 * 🇰🇷 South Korea: Republic of Korea Navy
 * Gwanggaeto the Great-class destroyers
 * Chungmugong Yi Sun-sin-class destroyers
 * Sejong the Great-class destroyers
 * Dokdo-class amphibious assault ship
 * 🇵🇹 Portugal: Portuguese Navy
 * 2 Karel Doorman-class frigates
 * 🇧🇪 Belgium: Belgian Navy
 * 2 Karel Doorman-class frigates
 * 🇶🇦 Qatar: Qatar Armed Forces
 * 4 Vosper Thornycroft Vita-class