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AS-90 self-propelled artillery.JPG
AS-90s firing in Basra, Iraq, in 2008
TypeSelf-propelled howitzer
Place of originUnited Kingdom
Service history
In service1992–present
WarsIraq War
Production history
ManufacturerVickers Shipbuilding and Engineering
No. built179
Mass45.0 long tons (45.7 t; 50.4 short tons)
Length9.07 m (29 ft 9 in)
Width3.5 m (11 ft 6 in)
Height2.49 m (8 ft 2 in)
Crew5 to move or 10 to use (incl. driver)

Armourmax. 17 mm (0.66 in) steel
155 mm L31 39 calibre gun (48 rounds)
7.62 mm NATO L7 General Purpose Machine Gun
EngineCummins VTA903T V8 diesel engine
660 hp (493 kW)
Power/weight14.66 hp/t
SuspensionHydropneumatic (Hydrogas)
420 km (261 mi) on road
Maximum 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 an armoured self-propelled artillery weapon used by the British Army.

It can fire standard charges up to 24.9 km (15.5 mi) using 39-calibre long barrel and 30 km (19 mi) with 52-caliber long barrel. The maximum rate of fire is 3 rounds in 10 seconds (burst); 6 per minute for 3 minutes (intense); and 2 per minute for 60 minutes (sustained).


AS-90 was designed and built by the Armaments division of Vickers Shipbuilding and Engineering (VSEL). Between 1992 and 1995, VSEL supplied 179 vehicles at a cost of £300 million ($480 million). The AS-90 was first deployed by the British Army in 1993.[1] The AS-90s were acquired to re-equip six of the eight self-propelled field artillery regiments (each of 24 guns) in the I (BR) Corps, replacing the 105 mm FV433 Abbot and older M109 155 mm Self Propelled Gun and FH70 towed howitzer. In 1999, VSEL became a part of BAE Systems.

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.[2] Critical to the programme 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.[3]

It remains in UK service and equips three field regiments supporting armoured infantry brigades for the foreseeable future. In 2008, there were 134 AS-90 in service further reduced to 117 by 2015.[4] In 2008 and 2009, a capability enhancement programme primarily upgraded AS-90's electronic system.

The initial expected out-of-service date for the AS-90 had been 2030,[5] but this was later delayed to 2032 with a replacement planned to enter service in 2029.[6]

On 24 April 2022, the Daily Express reported that AS-90s and 45,000 artillery rounds would be sent to Ukraine[7] but that was subsequently denied by Defence Secretary Ben Wallace.[8] On 14 January 2023, British Prime Minister Rishi Sunak announced that Britain would send 30 AS-90 to Ukraine, amongst other supplies (including 14 Challenger 2 tanks), for use in the ongoing Russo-Ukrainian War.[9]

To fill the gap in British Army artillery left buy the donation, the UK government announced they were buying 14 Archer Artillery Systems in March 2023. The deal was negotiated in just eight weeks as part of the urgent operational requirements procurement process; the first vehicles are to be fully operational by April 2024. The purchase will fill a hole in capabilities until a new system is decided upon as part of the Mobile Fires Platform program, which the Archer is one of the competitors in.[10]


AS-90 started in the mid-1980s as a private venture on the gamble that the tri-national SP70 would fail. When this did occur, the Ministry of Defence (MoD) issued a cardinal point specification on one page for a new 155 mm self-propelled gun. The MoD was also required to consider the US "Paladin", an upgraded M109 howitzer. The MoD undertook 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.[11] This would have introduced 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.[12] The Royal Navy did not adopt this gun system.[citation needed]


In 1963 certain NATO nations, including the UK, agreed to 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,[13] 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. In-to and out-of action times are less than 1 minute.


AS-90 on Salisbury Plain
  • Crew: 5, on board when moving (driver plus 4 gun detachment), full gun detachment 10 including driver, 4 detachment members in the turret.
  • Length: 9.07 m
  • Width: 3.3 m
  • Height: 3.0 m
  • Armour: 17 mm (maximum, steel)
  • Weight: 45 tons[vague]
  • Calibre: 155 mm
  • Range: 24.9 km (39 cal), 30 km (52 cal) standard charges
  • Rate of fire: 3 rounds in 10 seconds (burst), 6 rounds per minute for 3 minutes (intense), 2 rounds per minute for 60 minutes (sustained)
  • Secondary armament: 7.62 mm L7 GPMG
  • Ammunition carried: 48 projectiles and charges (31 turret and 17 hull), 1000 MG rounds
  • Main engine: Cummins VTA903T 660 bhp 90 degree V8, 4 stroke, liquid cooled, turbo diesel
  • Max speed: 55 km/h (Road)
  • Vehicle range: 370 km or 231 mi (Road)
  • Ground clearance: 0.41 m; Gradient: 60°; Vertical obstacle: 0.75 m; Trench crossing: 2.8 m; Fording depth: 1.5 m


Armatohaubica "Krab"


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.[citation needed]

Armatohaubica "Krab" – ("Cannon-howitzer crab")

Licensed "Braveheart" turret on a South Korean K9 Thunder SPG chassis, with modern "Azalia" BMS. Designed and integrated in Poland, by Huta Stalowa Wola and WB Electronics. Two Krab 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.[14] In 2014 production of Krab chassis was forwarded to Samsung Techwin, which will provide 120 units, replacing Polish built UPG chassis in serial vehicles.[15]


 United Kingdom

Future operators[edit]


  • 30 AS-90 promised by the United Kingdom on 14 January 2023.[18][19] The Ukrainian Armed Forces already operate several Krab vehicles, an AS-90 variant.

See also[edit]


  1. ^ Additional deployment information
  2. ^ George Robertson (9 June 1999), "AS90 Howitzer", House of Commons Debatea, UK Parliament, vol. 332, cc330-1W, retrieved 28 December 2016
  3. ^ "AS90 Braveheart 155mm Self-Propelled Howitzer". Retrieved 28 December 2016.
  4. ^ 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.
  5. ^ Quin, Jeremy (9 March 2020). "Artillery: Decommissioning:Written question – 24276". UK Parliament. Retrieved 10 March 2020.
  6. ^ Chuter, Andrew (29 July 2020). "British Army's AS90 howitzers to stick around amid replacement delay". Defense News. Retrieved 5 July 2022.
  7. ^ "United Kingdom to provide AS90 155mm tracked self-propelled howitzers to Ukraine". 24 April 2022. Retrieved 24 April 2022.
  8. ^ "UK military aid to Ukraine could rise to £500m, MPs told". the Guardian. 25 April 2022. Retrieved 25 April 2022.
  9. ^ Beale, Jonathan; Andersson, Jasmine (15 January 2023). "UK to send Challenger 2 tanks to Ukraine, Rishi Sunak confirms". BBC. BBC News. Retrieved 15 January 2023.
  10. ^ British Army buys 14 Archer howitzers to fill gap left by Ukraine aid. Defense News. 16 March 2023.
  11. ^ 155MM Study Looks To Pack More Punch Into The Royal Navy's Fleet Archived 12 February 2012 at the Wayback Machine BAe Systems Press release, 14 December 2007
  12. ^ Army to get new precision "search and destroy" anti-armour weapon Archived 11 December 2007 at the Wayback Machine MoD Press release, 20 November 2007
  13. ^ "Obturator for ordnance".
  14. ^ "Kraby dla 11. MPA – Altair Agencja Lotnicza". Retrieved 28 December 2016.
  15. ^ Samsung Techwin signs deal for delivering 120 K9 Thunder self-propelled howitzers to Poland., 17 December 2014.
  16. ^ "1st Regiment Royal Horse Artillery". British Army. Retrieved 4 August 2015.
  17. ^ "The Scottish Gunners". British Army. Retrieved 4 August 2015.
  18. ^ "Ukraine war: UK reveals number of tanks to be sent to Kyiv for first time". 15 January 2023. Retrieved 15 January 2023.
  19. ^ "PM accelerates Ukraine support ahead of anniversary of Putin's war". Retrieved 15 January 2023.