VSEL AS-90 (L-131)

     Notes:  The AS-90 evolved from the former international European program called GBT-155 which should have produced the SP-70 self-propelled artillery vehicle.  The AS-90 entered service in 1995, with 179 built for the British Army by the early 2000s; however, LRIP started as early as 1985.  Being a sort of “hurry up” program (the FV-433 Abbot and the M-109 were getting a bit too long in the tooth, and no suitable replacement was available), may components from other vehicles were used on the AS-90, including the L/39 155mm howitzer used on the FH-70, armor partially made from SP-70 armor panels, and a number of automotive components from the Challenger 1 main battle tank.  The “hurry up” nature did not, however, prevent the British from coming up with first-class SP artillery vehicle.  The test program that produced the AS-90 was named “GBT-155.” A further upgrade of the AS-90, the AS-90 Braveheart was cancelled and not reinstated into the budget until after the British intervention in the 2003 Iraq invasion. The AS-90 currently equips three field regiments of the Royal Horse Artillery and the Royal Artillery, with Bravehearts equipping some of the batteries of the Royal Artillery.

     The AS-90 is capable of firing any sort of munitions which are compatible with NATO 155mm howitzers in general, including those made by Singapore, China, the Middle East, and about a dozen other examples.  Though the L/39 gun is standard on British AS-90s, Kuwaiti AS-90s use an L/52 barrel as standard.  An L/45 barrel and an L/41 barrel have also been tested and are available, but have not yet had any customers. (These alternate barrels came out of the British Army tests of larger guns for the Braveheart, until they decided to go for the 52-caliber gun.)

The British AS-90 and the Braveheart

     As stated above, the British AS-90 uses a 155mm L/39 howitzer, and has a coaxial L-8A2 machinegun.  The turret is capable of fire from any facing direction. The driver is on the front left behind the glacis plate and the commander is in the turret on the left; he is not normally furnished a weapon and does not have a mount, but some have been retrofitted.  The commander has 360-degree vision blocks, but no cupola.  The loader has a hatch on the right turret roof, but it is a simple hatch and has no vision blocks.  On either side of the turret are large armored boxes for storage (two on the right and three on the left); these are rather large boxes, almost 2x1 meters.  The position where the third box would be on the right side is blocked by a hatch on the side of the turret. On either side of the main gun, facing outwards, are cluster of five smoke grenade launchers. Behind the commander and loader’s hatches is a large flat area of deck space, which gets pressed into equipment storage in short order.  The rear of the turret has a pair of large gears; a conveyor (normally carried by the PLS DROPS-type vehicle that are used for such, but sometimes carried by the AS-90 externally) leads directly from the resupply truck to the AS-90.  The AS-90 has a 7-compartment automatic fire detection and suppression system. The AS-90 fitted with an advanced navigation and gunlaying system (AGLS); as the navigation system lies on inertial navigation, it has a somewhat limited capacity for self-laying and conducting fire missions on its own, and usually depends upon an FDC for fire coordinates, which the AS-90’s fire control computer crunches and automatically feeds to the gun.  Computerized fire control helps this, as does a mapping module.  Gun loading is semiautomatic, with an arm taking the round from the magazine to the gun breech, and the loader puts in the bagged charged.  The magazine holds 31 rounds; 17 more are carried in a bin on the floor of the vehicle and must be loaded into the magazine or breech manually.  The loader may also have to shift around the rounds in the magazine to present the autoloader with the proper rounds to be fired; the 17 rounds in the bin are usually special rounds such SFMs and suchlike, and are normally loaded manually by the loader.  The loader and the crew of the ammunition truck also load the rounds from the truck; often, the loader himself must load these fresh rounds into the magazine and bin, as well as charge bags. Needless to say, the loader is a busy fellow during a fire mission.

     Power for the AS-90 is the same as that of the Braveheart, being a Cummins VTA-903 turbocharged diesel with an automatic transmission.  Some automotive components are also taken from the Challenger 1 tank. The engine and transmission form a unitary powerpack, and are removed and installed together. Layout for the AS-90 and the Braveheart version is essentially identical; what’s different is the gun and the electronics. As with many British-made vehicles, the interior includes a ration cooker/water heater that is large enough for the entire crew’s rations at once. Another difference is the secondary armament; the loader’s hatch normally has an L-7 machinegun on a pintle mount (though his seat rotates); on the Braveheart, an additional heavy weapon is mounted by the commander’s hatch.  In other crew protection, the AS-90 has an overpressure NBC system with a vehicular system backup, and a 5kW APU for powering systems with the engine off.  There a door in the rear, primarily for reloading the AS-90 from an external source, but also used for entrance and exit.  This door is small, to give the AS-90 as small an open area as possible, to enter and exit, the crew much crouch almost double.

     The gun of the AS-90 can be quickly and fairly easily upgraded; 75 minutes in 2^nd Echelon maintenance is all it takes to put a new, longer barrel on an AS-90 and calibrate the fire control equipment to the new barrel.  The gun, regardless of length, has an elevation of +70 degrees and a depression of -5 degrees.

     The AS-90 Braveheart entered service with British Forces in 1992, though production and adoption has been slow.  The AS-90 Braveheart is a development of the Kuwaiti AS-90D, and therefore the Braveheart has superior performance in desert conditions.  The original termination occurred due to things like non-standard charges and other minor things which, altogether, made the Braveheart difficult is not impossible to integrate into existing artillery units.  These problems were later solved. The Braveheart has an additional loader, as it was discovered that on the AS-90, one loader could all too often not keep up. (Unfortunately, the capacity of the ration heater remained unchanged, so one crewmember has to wait a bit for his dinner.) The Braveheart may be equipped with an L/39 or an L/52 cannon barrel, though none have used the L/39 barrel since testing phase.  The Braveheart has a Dynamic Reference Unit (DRU) allowing the Braveheart to fire accurately with up to a 20 degree cant.  Both charges and projectiles are handled automatically, leaving only fuze attachment to the crew’s devices.  Unlike the AS-90, the Braveheart does not require stabilizing spades at the rear.  This is due to a hydrogas suspension system for the rear 4 shock absorbers.  Included in the fire control system is the automatic loading system and the vehicle’s fire control system.  The fire control system can fire, position, and produce a fire solution using on-board mapping systems and computers.  These computers (and radios) are helped by the installation of GPS with an inertial guidance backup.  In essence, the Braveheart does not need an FDC, though one is often used to provide faster solutions and intelligence; indeed, the Braveheart crew doesn’t need to even open their hatches or stick their heads outside of the vehicle to produce accurate fire (until it needs reloading, of course).  This is enhanced by a telephone to talk to the crew. At the rear of the turret is an air conditioner.  The Braveheart has the British equivalent of a BMS with vehicle and ammunition state monitors, and navigation screens for the driver and commander, and firing information for the gunner and loaders.  There is a mapping module and computer, able to plot courses and waypoints.

     The fire control suite includes automatic lay of the gun from computer coordinates.  Semi-accurate fire is available with the gun moving at a slow speed, but a full stop is recommended.  Advanced fire control is available for direct fire or direct lay situations, or the coaxial machinegun.  In addition, the Braveheart uses LINAPS, the Laser Inertial Digital Gun Sight, which provides exact bearing and elevation of the barrel and the FIN3110 ring laser-gyro, which is embedded to the GPS, as well as incidental benefit to direct fire for the main gun and coax.  The Braveheart is powered by a 660-horsepower turbocharged diesel engine, coupled to an automatic transmission, and an 8kW APU is provided to power systems while the engine is off. The Braveheart is capable of firing virtually any 155mm howitzer round, including the newest US M-982 Excalibur GPS-guided rounds.  It is also capable of firing the new Denel Assegai family of 155mm rounds, which include VLAPs (Velocity-enhanced Long-range Artillery Projectile).  Other special rounds useable include US and German Sensor-Fused Munition (SFM) rounds.

     Action in Iraq led to the development of the Braveheart Desert AS-90.  This blends features from the Braveheart with the AS-90D, and the improvements of the AS-90D are present on the Desert Braveheart. The Desert AS-90 has a thermal cover and thermal paint, which provides protection to the crew from the hot metal of the vehicle.  This has incidental benefit in evading thermal imaging and passive IR sensors, giving the observing vehicle -2 to detect the Desert Braveheart using IR, Thermal, or FLIR sensors. The Desert Braveheart also carries a radio and radar jammer, making radar detection one level harder, attempts at MIJI done at -4, and radio-guided missiles are at -3 to hit. The Desert AS-90 is otherwise different in its filters, engine appointments, and power cooling systems, as well as wider tracks for negotiating sandy terrain.

     A modification of the AS-90 Braveheart’s turret was mounted on a PT-91 Twardy tank chassis, creating the Polish Krab self-propelled artillery system. The Braveheart underwent trials in Sweden, but ultimately not chosen due to cost; trials are currently being done in India with a Braveheart turret mounted on the chassis of a T-72.

The Kuwaiti Version: AS-90D

     The AS-90D is essentially an evolved version of the AS-90, optimized for the desert fighting environment. This includes a high-efficiency air filtration system and better air filters (under the glacis, they take up most of the front end).  A 5kW APU has been added, along with a powerful air conditioning system which can cool the interior of the vehicle even with the back loading doors open.  The oil, fuel, and transmission fluid lines are specially sealed against the elements (especially dust and sand), as are the engine, transmission, and drive train themselves.  The Kuwaitis chose to keep the ration heater, as well as install a small refrigerator (about the size of a medium cooler).  The tracks are about 0.3 meters wider each to provide better traction in deep sand. Rubber and metal shields are installed on the lower hull to keep down the sand that the AS-90D generates itself when moving, and the driver can erect a small windscreen for when he drives with his head outside of the hatch.  The Kuwaitis wanted better direct-fire capability for its AS-90Ds, so a ballistic computer has been installed for use by the main and coaxial machinegun in direct fire.  The Kuwaitis also chose to give their AS-90Ds a commander’s machinegun.  (As with a standard AS-90, the commander’s seat rotates and the machinegun is on a track.)  Some of the Braveheart’s howitzer fire control was available for the AS-90D, with the GPS, mapping computer, and fire solution computer being installed.  These computers aren’t as powerful as later iterations, and fire solutions useful for accurate fire are best done by an FDC.  (Without an FDC, increase scatter by 5 meters.)  The gun is an L/52 gun.

     Twilight 2000 Notes: Few Bravehearts made it into active service in the Twilight 2000 timeline; perhaps 15% of Britain’s AS-90 force were Bravehearts.  The rest of the AS-90s were “stock” AS-90s, with 60% of them having L/39 barrels, 25% with L/52 barrels, 12% with L/45 barrels, and 3% with L/41 barrels.  The Desert Braveheart never made it to the party, but some (about 10) AS-90Ds made it into Kuwaiti service.

*Roof AV for the turret and hull are 5.  Floor AV is 6Sp.

Vickers FV-433 Abbot

     Notes: This British SPH also served with India (who still operates some 80 “Value Engineered” Abbots).  It was rapidly replaced by the AS-90 series in British service, fast enough to make them a hot item on the collector’s market with many left over for museum pieces.  In particular, they are common in European “tank-driving” adventures since they are lighter and easier to care for than a real tank.  The comedian Ross Noble revealed on the 3 July 2011 Top Gear show that he owns and operates an Abbot, and he is far from alone.  The Abbot is the SPH member of the FV-430 family of vehicles, though the chassis used is a stretched version of the FV-430 chassis with a different engine(s) and different configuration of its unitary powerpack.  The Abbot entered British service in 1965, and left service in 1995.   The designation of FV-433 Abbot continues the World War 2 convention of giving artillery vehicles ecclesiastic names, though it was the last artillery vehicle in the British Army to receive such a name.

The Standard Abbot

     Unlike most of its contemporaries, the Abbot was equipped with the then-new L-13 105mm howitzer instead of a 155mm gun.  This was done partially for reasons of economy and partially because of the limitations of the FV-430 chassis.  In addition, the US-built M-109, which did have a 155mm gun, came into British service at about the same time, and it was felt that a relatively high-mobility howitzer in the Abbot might be desirable. A new family of ammunition was designed for the Abbot’s gun.  It was similar to US 105mm howitzer ammunition of the time, using mostly US-pattern primers for the shells and reduced-charge bag charges, ignited by electrical primers.  In addition, the Mark 2 series included an improved-lethality HE round, improved smoke, colored marker (red and orange), Illumination, and HESH shells for direct-fire antivehicle combat. The L-13 on the Abbot has a maximum depression of -5 and elevation of +70, and HESH shells were designed for the L-13 because the gun was able to depress enough to engage vehicles.  The shells also had new charge settings: Normal and Super. The shells were rammed into the breech by an electrical servomotor, but the charges were inserted by hand.  In addition, though turret traverse was electric, gun elevation and depression was manual. The small turret meant that there was no room for fancy fire control equipment, but it did have simple scale-type sights to get the gunner onto the right elevation and traverse. These sights were replaced in the early 1970s by a relatively-primitive fire control computer called FACE.  Along with a data-transmitting secure radio and another simple computer called AWDATS, the Abbot was able to have commands from the FDC be inputted directly into the FACE. There was no coaxial machinegun, though the commander had (at first) an L-4A4 Bren Gun, and later an L-7 machinegun.  Though he had no cupola, his seat rotated by moving his body and the machinegun was on a track, making the loader able to fire at almost any ground target.  The turret has a 360-degree rotation, and the gun elevates to +70 degrees and depresses to -5 degrees, making quite capable of direct fire.

     The Abbot had a standard long-range radio and a short-range radio for general conversations; in addition, the Abbot had hookups for the use of field telephones (one line going to the FDC, and one or two going to adjacent guns).  After the more flexible Clansman series of radios were installed, field telephone use tapered off, though the capability remained.  In addition, the commander could speak into a bullhorn on the roof of the turret from his position (presumably to give and take orders in high-noise environments). Setup is similar to most such vehicles, with the driver on the front right, commander on the turret left, and a loader’s hatch on turret right.  The Abbot had no shortage of crewmen, but the small degree of automation present in the Abbot made this necessary; however, two of these crewmen ride in one of the ammunition carriers that travel with the Abbot.  At the rear of the vehicle is a large door for crew entry and exit as well as ammunition resupply. The driver has a gas pedal and a pair of laterals to steer and brake, similar to the M-113 APC; the original engine was a Rolls-Royce K60 multifuel engine with 240 horsepower, but this was later replaced with a Cummins turbocharged diesel with the same horsepower, but mechanically less complex.  The engine is on the left, so the driver had to be relocated to the front right. In addition to his loading duties, the on-board loader operates the long-range radios. A collective vehicular NBC system protects the crew. The transmission is automatic, and the Abbot was amphibious after raising a flotation screen; in water, the Abbot is propelled by track movement.  Suspension is by torsion bars, with no shock absorbers.

     Popular use of the Abbot includes the use of restored retired Abbots for civilian tank-driving adventures.  The Scottish TV series Gary: Tank Commander features an FV-433 as “the Tank.”  An FV-433 was used in the final episode of the British TV series, Spaced. In the 2012 movie The Dark Knight Rises, two FV-433’s comprise part of the National Guard’s forces.

The “Value-Engineered” Abbot: Artillery on the Cheap

     When India first ordered the Abbot, they were not the economic powerhouse that they are now and couldn’t afford the best stuff; in addition, a lot of countries were snubbing India, since they dared to develop nuclear weapons.  So when they ordered the Abbot, they asked that Vickers shave off the price as much as possible and still produce a working SP howitzer.  This was the “Value-Engineered” Abbot.  This Abbot had basically no power-operated features – the electrical turret traverse was deleted, as was the shell rammer.  The collective vehicle NBC system was removed, the crew relying on their own personal NBC equipment.  It has no night vision. The “Value-Engineered” Abbot had no provision for swimming.  The sight was a simple dial sight, and the radios were basic ones that were essentially out of date.  68 of the 80 Abbots that India still uses are of this type.  A further 20 are used by the British and kept at the BATUS in Alberta, Canada, for use as training vehicles.

     Twilight 2000 Notes: The British Army still had about 40 Abbots in service in 1995 in the T2K timeline.  In addition, those owned by private individuals were “borrowed” by the British Army; even some museum pieces were reactivated.  The Indians, of course, used theirs, and the 20 “Value-Engineered” Abbots at the BATUS saw service with the Canadian Army against the Russians or Quebecois.