Difference between revisions of "Goalkeeper CIWS"

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Goalkeeper is a Dutch close-in weapon system (CIWS), which defends ships against incoming missiles and ballistic shells. This system consists of an autocannon and an advanced radar which tracks incoming fire, determines its trajectory, then aims the gun and fires; all in only 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. The system can also be deployed to protect airfields.

Development

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.

Description

Target selection

Goalkeeper has two radar sub-systems; search and track, which operate in conjunction with one another to identify and prioritise targets before engaging the highest priority.

The 2D I band search radar, which can track up to 18 targets at once, generates a threat picture which the gun system uses to identify threats and prioritise. Once a target has been prioritised the engagement radar is slewed to the target bearing indicated by the search radar. 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, was selected for the system. The 30 mm round has a greater mass than the M61 Vulcan used in the Phalanx CIWS so that it has greater stopping power despite the similar muzzle velocity and range.

The 30 mm round has a discarding nylon sleeve, or 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 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^{[citation needed]} to be 5.5 seconds with the firing synchronised to start the engagement at a range of 1,500 m and ending with a kill at 300 m.

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
• 100% Kill distance: 500 m
• Cost: €16 million

Operators

• United Kingdom: Royal Navy
  • HMS Illustrious (R06), HMS Invincible (R05), HMS Albion (L14), HMS Bulwark (L15) and the four Type 22 batch 3 frigates.
  • Illustrious and Invincible were previously equipped with Phalanx. They were replaced with three Goalkeepers (per ship). The other ship of the same class, HMS Ark Royal (R07), retained the Phalanx.
• 23x15px Croatia^{[citation needed]}
• Chile: Chilean Navy
  • 2 Jacob van Heemskerck-class frigates
• Netherlands: Royal Netherlands Navy
  • The system entered service with all Royal Netherlands Navy's large surface ships since in 1980.
• 23x15px 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
• 23x15px Portugal: Portuguese Navy
  • 2 Karel Doorman-class frigates
• Belgium: Belgian Navy
  • 2 Karel Doorman class frigates

External links

• ThalesGroup .pdf
• RN page about the Goalkeeper CIWS.
• General Dynamics fact sheet.
• Naval weapons.com article on the Goalkeeper CIWS.
• Goalkeeper CIWS at the Royal Netherlands Navy LCF Frigate information page
• Goalkeeper CIWS on Youtube