Goalkeeper CIWS

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Goalkeeper CIWS on a British Invincible class aircraft carrier

Goalkeeper is a Dutch close-in weapon system, which defends ships against incoming missiles and ballistic shells. The system consists of an autocannon and an advanced radar which tracks incoming fire, determines its trajectory, then aims the gun and fires in a matter of seconds. The system is fully automatic, needing no human input once activated. The name comes from the football/soccer position. The system is made by Thales Navy Netherlands, and over 50 have been produced. The system can also be deployed to protect airfields.

1 Development
2 Description
3 Specifications
4 Comparison to Phalanx
5 Operators
6 External links

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

The system first acquires a target using the 2D I band search radar, which can track up to 18 targets at once. The engagement radar is then slewed to the heading indicated by the search radar. The engagement radar operates in both I band and K band, which enables the engagement radar to use the search radar's signal to find the target quickly without additional searching. Also, data from the I band and K band return signals can be compared to increase resistance to electronic countermeasures (ECM) and clutter. The engagement radar is also backed up by an optical system.

Target hit by Goalkeeper

The GAU-8/A Avenger 30 mm gun, as used by the A-10 Thunderbolt II was selected for the system, primarily because, although the muzzle velocity and range are similar to the M61 Vulcan, the projectiles are much heavier (430 grams compared to 100 grams). This is critical because 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 detonate the warhead of the missile or obliterate the missile.

The system's reaction time to a Mach 2 sea-skimming missile like the Russian SS-N-22 Sunburn from automatic detection to kill is reported to be 5.5 seconds with the engagement starting at a range of 1500 m and ending with a kill at 300 m.

Gun: GAU-8/A Avenger/77 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 degrees at 80 degrees/sec.
Muzzle velocity: 1,109 m/s (MPDS round).
Turret Speed 360° in 3.8 seconds
Rate of fire: 70 or 75 rounds/second (4,200 rounds/minute).
Maximum burst size: 300 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. Beamsize 1.5 degrees horizontal, 60 degrees vertical. Rotates at 60 rpm. Range approx 30 km.
Engagement radar: I band and K band monopulse cassegrain.
Optical system: TV
Kill distance: 500 meters
Cost: £8 Million

The Phalanx CIWS is another system that is widely used in the same role, there are several key differences between the two systems:

Goalkeeper's projectiles are much larger (30 mm versus 20 mm) and have greater kinetic energy.
Goalkeeper is twice as expensive as the Phalanx.
Phalanx can be welded to any section of deck and plugged in, while Goalkeeper requires significant "deck penetration" and integration.
Phalanx's ammo drum is mounted directly on the gun, while the Goalkeeper is reloaded from below deck.
Phalanx can only track and engage one target at a time, while Goalkeeper can track 18 targets and switch to engage the greatest threat.^{[citation needed]}
Both weapons have similar maximum ranges, however Goalkeeper's kill distance is reportedly slightly further (350 to 500 meters compared to 300 meters for the Phalanx).