Advanced Gun System

.

Originally designed for mounting as a vertical gun, this 155 mm (6.1") caliber gun has since been slated for mounting within a more conventional turret arrangement. The AGS is designed to offer a weapon system capable of delivering precision munitions at a high rate of fire and at over-the-horizon ranges. As a vertical gun system it would only have been capable of firing guided munitions; the turret mounting will allow the use of unguided munitions as well.

Description

The AGS uses the same 155 mm caliber as most American field artillery forces, although it does not share the ability to fire the same ammunition. Instead, a new range of ammunition is under development for this weapon. The gun barrel is 62 calibers long, and is able to fire the entire magazine (300+ rounds) with an average rate of fire of ten rounds per minute using a water cooled barrel. The AGS is to be mounted in a turret specifically designed for the Zumwalt class destroyer with fully automated ammunition supply and operation. The turret itself is designed to be stealthy, allowing for the entire length of the barrel to be enclosed within the turret housing when not firing.

Ammunition

The development of new ammunition for the AGS under the name Long Range Land Attack Projectile (LRLAP) is one of the major advances offered by the AGS program. The munitions are to be highly accurate, with a circular error probable of 50 m or less. Lockheed-Martin conducted a flight test of the munition in July 2005, reporting a flight distance of 59 nautical miles (109 km).

The LRLAP ammunition features separate projectile and propellant portions. Total weight is 225 pounds (102 kg), including a bursting charge of 24 lb (11 kg). The maximum length of the combined munition is 88 inches (223 cm), amounting to about 14 calibers.

Operation

A primary advantage of the AGS over the existing Mark 45 5" gun which equips most major surface combatants of the US Navy is its increased capability for supporting ground forces and striking land targets. With a 10 round per minute capacity, it offers the ability to deliver firepower close to that of a battery of six 155 mm howitzers. This will increase the utility of vessels equipped with the weapon, especially in areas in which the US Navy exercises absolute sea supremacy.

Usage

The AGS is currently only slated for inclusion on the Zumwalts although it could also be included in other future ship designs. No plans have been revealed to retrofit it to current ship designs. The shortening of Zumwalt procurement to two ships increases the likelihood that BAE will attempt to market AGS to other programs.

History

There has been research on extending the range of naval gunfire for many years. Gerald Bull and Naval Ordnance Station Indian Head tested an 11 inch sub-calibre saboted long-range roundcitation | first=L. Bruce | last= Van Dam|title = Does the Past Have a Place in the Future? The Utility of Battleships into the Twenty-First Century | url=http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A367903&Location=U2&doc=GetTRDoc.pdf |format=PDF |publisher=US Army Command and General Staff College| place=Fort Leavenworth, Kansas|date=1999-06-04, citing a letter from Major Tracy Ralphs to Senator John Warner on 1999-02-25] in a stretched 16"/45 Mark 6 battleship gun in 1967.cite web | url = http://www.navweaps.com/Weapons/WNUS_16-50_mk7.htm |title = United States of America 16"/50 (40.6 cm) Mark 7 | publisher = Tony DiGiulian, navweaps.com | date= 2008-08-09] The Advanced Gun Weapon System Technology Program (AGWSTP) evaluated a similar projectile with longer range in the 1980s. After the battleships were decommissioned in 1992, the AGWSTP became a 5" gun with an intended range of convert|180|km|mi, which then led to the Vertical Gun for Advanced Ships (VGAS). The original DD-21 was designed around this "vertical gun", but the project ran into serious technology/cost problems and was radically scaled back to a more conventional 6.1 inch Advanced Gun System (AGS). One advantage of this move was that the gun was no longer restricted to guided munitions.

ee also

*4.5 inch (114 mm) Mark 8 naval gun The main British naval gun, currently being upgraded by BAE to take advanced 155 mm munitions. [cite web|url=http://www.royal-navy.mod.uk/server/show/ConWebDoc.13557|title=Royal Navy Prepares to Roll out the Big Guns|publisher=Royal Navy|date=2008-08-28]

Notes and references

External links

* [http://youtube.com/watch?v=pg1uHRVx8-I Video - Advanced Gun System (AGS) Employment in Asymmetric Warfare Simulation Scenario]
* [http://youtube.com/watch?v=ilwIhIwf5yI Video - Navy Advanced Gun System (AGS) Non-combatant Evacuation Simulation Scenario]