AS-90

AS-90

AS-90s firing in Basra, Iraq in 2008
Type Self-propelled artillery
Place of origin United Kingdom
Production history
Manufacturer Vickers Shipbuilding and Engineering
Number built 179
Specifications
Weight 45.0 tons (100,800 lb)
Length 9.07 m (29 ft 9 in)
Width 3.5 m (11 ft 6 in)
Height 2.49 m (8 ft 2 in)
Armour max. 17 mm (0.66 in) steel
Main
armament
 155 mm L31 39 calibre gun (48 rounds)
Secondary
armament
 7.62 mm NATO L7 GPMG
Engine Cummins VTA903T V8 diesel
660 hp (493 kW)
Power/weight 14.66 hp/t
Suspension Hydropneumatic (Hydrogas)
Operational
range
 420 km (261 mi)
on road
Speed 53 km/h (33 mph)
Crew member with AS-90 shell
Inside AS-90 on Exercise Steel Sabre, 2015

The AS-90 (Artillery System for the 1990s; known officially as Gun Equipment 155 mm L131) is a lightly armoured self-propelled artillery piece used by the British Army.

The AS-90 was first deployed by the British Army in 1993.[1] 179 AS-90s were acquired to re-equip six of the eight self-propelled field artillery regiments (each 24 guns) in the 1 (BR) Corps, replacing the 105 mm FV433 Abbot SPG and older M109 155 mm Self Propelled Gun. It remains in UK service and will equip three field regiments supporting armoured infantry brigades for the foreseeable future. 134 in service in 2008, 117 in 2015.[2]

AS-90 was designed and built by the Armaments division of Vickers Shipbuilding and Engineering (VSEL), whose parent company became BAE Systems in 1999. VSEL provided 179 vehicles between 1992 and 1995 at a cost of £300 million ($480 million USD).

The AS-90 underwent a capability enhancement program in 2008 and 2009, primarily relating to upgrades of the AS-90's electronic system.

In 1999, Marconi Electronic Systems was contracted to upgrade British Army AS-90s to include a 52 calibre gun in order to increase the range of the artillery.[3] Critical to the program was a bi-modular charge system from Somchem of South Africa (selected after extensive trials of ammunition from many suppliers), which offered greatly reduced barrel wear. However, this ammunition failed to meet the requirement for insensitive munitions and the project was terminated.[4]

Development

AS-90 started in the mid-1980s as a private venture on the 'gamble' that the tri-national SP70 would fail. When this duly occurred, the Ministry of Defence (MoD) issued a cardinal point specification on one page for a new 155 mm SPG. Four tenders were submitted, and AS-90 was the only offer that was not 'brochureware'. The MoD was also required to consider the US "Paladin", an upgraded M109 howitzer.

The MoD has undertaken studies in 2006-09 to "up gun" the Royal Navy's main shipboard gun armament, the 4.5 inch Mark 8 naval gun, to accept 155 mm ammunition from the AS-90.[5] This would introduce a common gun calibre for the British Army and Royal Navy, helping with ammunition logistics, and encouraging joint Army-Navy development of extended range and precision guided shells.[6]

Design

In 1963 certain NATO nations, including the UK, agreed a Ballistics Memorandum of Understanding for a 155 mm 39 calibre ordnance and a baseline projectile with the shape used for the US M549 rocket-assisted shell. The AS-90 uses a conforming 39 calibre barrel which fires the L15 unassisted projectile out to a range of 24.7 km. However, this was a new design of ordnance using a split sliding block breech with Crossley obturation, instead of the more usual screw breech, to permit bagged charges (no metal cartridge cases). The breech mechanism has a primer magazine holding 18 primers. The standard ammunition is that designed for FH-70 (L15 HE and associated propelling charges) although in training the less effective but cheaper M107 with Green and White propelling charges is used.

It is fitted with an auxiliary power unit to eliminate the need to run the main engine to keep the batteries charged while stationary; electrical servos drive the automated elevation, traverse, magazine, shell transfer arm and loader as well as power for electronics and communications.

The vehicle is fitted with an autonomous navigation and gun laying dynamic reference unit (DRU) mounted on the trunnion. All main turret functions are controlled by a Turret Control Computer (TCC) with control and display units for the No 1 (Detachment Commander), No 2 (loader) and No 3 (layer). The combination of the DRU, TCC and powered laying controls provide autolaying. Every gun is fitted with a radar Muzzle Velocity Measuring Device. Reversionary mode laying uses deflection laying via the direct fire sight.

The gun can be brought into action fully closed down, the barrel can be clamped and unclamped from within the vehicle. Into and out of action times are less than 1 minute.

Characteristics

AS-90 on Salisbury Plain

Variants

Haubicoarmata "Krab"

AS-90D - Modified for desert use. Thermal protection for crew and extra cooling for engine and machinery. Tracks adapted for reduced wear in sandy conditions.

AS-90 "Braveheart" - Basically the AS-90, but fitted with the 52 calibre length gun. This project was terminated due to non-compliant propellant charges.

Haubicoarmata "Krab" - (eng. Howitzer-cannon Crab) Licensed "Braveheart" turret on a K9 Thunder chassis, with modern "Azalia" BMS. Designed and integrated in Poland, by Huta Stalowa Wola and WB Electronics. Two Krab ("Crab") prototypes were built in 2001, and successfully completed all required evaluations and state acceptance trials. Initial serial production started in 2008, with eight units delivered to Polish Land Forces for testing.[7] In 2014 production of Krab chassis was forwarded to Korean Samsung Techwin, which will provide 120 units, replacing Polish build UPG chassis in serial vehicles.[8]

Operators

 United Kingdom

See also

References

Wikimedia Commons has media related to AS 90.
  1. ↑ Additional deployment information Deagel.com
  2. ↑ UK Ministry of Defence, ed. (23 April 2015), Vehicle & Aircraft Holdings within the scope of the Conventional Armed Forces in Europe Treaty Annual (PDF) (2015 ed.), p. 4.
  3. ↑
  4. ↑ Army Technology - AS90 BRaveheart 155mm - Self Propelled Howitzer
  5. ↑ 155MM Study Looks To Pack More Punch Into The Royal Navy's Fleet BAe Systems Press release, 14 December 2007
  6. ↑ Army to get new precision "search and destroy" anti-armour weapon MoD Press release, 20 November 2007
  7. ↑
  8. ↑ Samsung Techwin signs deal for delivering 120 K9 Thunder self-propelled howitzers to Poland. armyrecognition.com, December 17, 2014.
  9. ↑ "1st Regiment Royal Horse Artillery". British Army. Retrieved 4 August 2015.
  10. ↑ "The Scottish Gunners". British Army. Retrieved 4 August 2015.
  11. ↑ "The West Midland Gunners". British Army. Retrieved 4 August 2015.
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