TANKS HAVE BEEN around for more than 80 years; developed by the Admiralty, they were taken on board by the Army and have spawned a wide variety of go-anywhere vehicles. They are extremely expensive to produce and as applications alter, so too does the requirement.

Currently in the British Army inventory there are several sub-types of tracked vehicle but only two heavyweight main battle tanks (MBT), Challenger 1 and 2, the latter gradually replacing the former. Vickers Defence Systems developed the Challenger 2 as a private venture following the poor showing of the Challenger 1 during the Gulf War. In that conflict the MBT performed well, but there was a need for a more able MBT to continue to support NATO effectively. The French put forward their Leclerc, the Germans fielded the Leopard 2 (Improved) and the Americans leaned on the British with their M1A1 Abrams. In the event, the Vickers Challenger 2 saw off the opposition and came through rigorous tests with flying colours.

It was intended that the Mk 2 would replace only half the existing fleet of Challenger 1s as well as the ageing Chieftain tanks, but the UK MoD decided to replace the entire MBT fleet with the new tank. Costing some £4m each, the Challenger weighs in at 62,500kg and has a maximum speed of 56km/hr. Powered by a Rolls-Royce Perkins CV-12 Condor V-12 12-cylinder engine, with six forward and two reverse gears, it has a range of 450km.

Armament consists of a newly developed Royal Ordnance L30A1 120mm rifled gun; 1 x 7.62mm co-axial machine gun, 1 x 7.62mm anti-aircraft gun and 10 smoke grenade launchers. The use of the L30A1 is of interest as most other MBTs are fitted with smooth-bore barrels, the rifle gun allows the use of high-explosive squash head (HESH) rounds to be fired as well as the more conventional armour-piercing fin-stabilised discarding Sabot (APFSDS) rounds. Housed in a newly designed Chobham armour and welded-steel turret, the gun is fully electrically stabilised and able to traverse 360 degrees.

It transpired that during Exercise Saif Sarefa in Oman during 2001 the Challenger 2 had problems with dust. These arose from penny-pinching by Whitehall accountants who would not pay for better dust filters and were not the result of any shortcomings in the MBT. However, the Oman Army that also uses the Challenger 2, had no such problems having fitted the correct manufacturer's recommended dust filters.

The Challenger 1-based CRARRV (Challenger armoured recovery and repair vehicle) continues in service with the British Army, and while the Mk 1 will disappear this year, the CRARRV will continue until it also is replaced by the new Challenger 2-based heavy armoured repair and recovery vehicle. Deliveries will begin towards the end of this year.

Also from the Vickers stable comes the AS-90 self-propelled gun. This first saw the light of day in 1981 and following trials was chosen by the British Army in 1989. Powered by a Cummins VTA 903T 660T-660 V-8 diesel engine, it is capable of 55km/hr and has a range of 370km. The main armament is a 155mm gun with a maximum range of 24,700m using standard ammunition, or with extended-range full-bore ordnance, 30,000m. The AS-90 is still capable of development using different calibre guns of 155mm. Trials are in progress.

Of smaller tracked vehicles in the British Army the Alvis-built CVRT (combat vehicle reconnaissance tracked) Scorpion also has spawned variants. First seen in 1969, the Scorpion is no longer in the British Army although variants continue, including the FV102 Striker anti-tank vehicle with five Swingfire anti-tank guided missile launchers; FV103 Spartan armoured personnel carrier; FV104 Samaritan ambulance; FV105 Sultan command vehicle; FV106 Samson recovery vehicle and the FV107 Scimitar reconnaissance vehicle with a 30mm gun. Other variants in the Army are the Sabre, fitted with a Vickers Defence Systems Fox light armoured car turret, also with a 30mm cannon and additionally a 7.62mm co-axial machine gun.

The Scorpion CVRT family is now fitted with the well-proven Perkins T6-3544 turbo-charged six-cylinder diesel engine in place of the originally fitted Jaguar J60 4.2-litre petrol engine. Over the years the CVRT has proved itself in combat, notably during the Falklands crisis in 1982 and the Gulf War in 1991, two very different climates and terrains. Fast and manoeuvrable the CVRT has a range of 644km at a maximum cross-country speed of 50km/hr. On tarmac it can travel at 80km/hr. It has been a tremendous success for Alvis. Scorpion derivatives have been sold worldwide and production did not finally cease until 1996 when over 4,000 had been manufactured.

The FV103 Spartan armoured personnel carrier (APC), has a crew of two and space for up to five fully equipped infantry and the purpose-built Warrior APC has a crew of three and can accommodate seven fully equipped soldiers. It was to a specification by, what was then, the Fighting Vehicles and Engineering Establishment at Chertsey that work commenced on a new generation of APCs. GKN had been developing their Sankey mechanised combat vehicle 80 (MCV 80) and they won the contract for a prototype to General Staff Requirement 3533.

First tested in 1984 the MCV 80 was successful and quantity orders were placed with GKN. Production was centred at the GKN facility at Telford and commenced in 1986. Named Warrior it was declared operational in 1988. Fitted with a Vickers turret carrying a main armament of a 30mm L21 Rarden cannon and a 7.62mm L94A1 co-axial chain gun, the Warrior is powered by a Perkins CV-8 TCA diesel engine and has a range of 660km.

Warrior production ceased in 1995 after 789 vehicles had left the factory. During a decade of production several variants had been built, including command vehicles, artillery observation vehicles fitted with a dummy Rarden gun and carrying a Marconi battlefield artillery engagement system and EMI portable surveillance and target acquisition radar; FV512 recovery vehicles and FV513 repair vehicles.

All variants of the Warrior have been successful and have handled a wide variety of tasks for the British Army. On deployment in Bosnia they were fitted with armour on the front and sides. Although this proved effective against tank shells and small arms, it was of no help against the friendly fire of USAF A-10 Thunderbolts. Three Warriors were destroyed. At the other end of the scale in tracked vehicles the Hagglunds BV206S APC also has proved to be a success. Developed by Hagglunds and the Swedish Army, the prototypes were completed in 1989 and entered service with the Swedes that year.

Alvis bought Hagglunds and the BV206S is now unlike anything else on the battlefield. It is an all-terrain APC consisting of two separate all-steel bodies linked together by a steering unit. Both units are mounted on rubber-band type tracks and both are armoured to protect occupants from shell splinters and small-arms fire at point-blank range. The window glass is also armoured to the same level.

Carrying a crew of two, with space for two others in the front compartment, the rear unit has space for eight fully equipped infantrymen. The BV206S is powered by a Steyr M16 six-cylinder in-line diesel engine giving it a maximum speed of 50km/hr and a range of 370km. It is also capable of defence, a single 12.7mm machine gun being mounted on the roof of the front unit. Alternatives include a 7.62mm machine gun or a 40mm grenade launcher.

The BV206 is fully amphibious and is also air-transportable either by helicopter or fixed wing, it weighs 5,300kg empty. Mainly used by the Royal Marines in the UK, the BV206 is also now in service in France, Sweden and Germany. This review of the main tracked vehicles in service with the British Army cannot fail to include the venerable Chieftain. Designed by Vickers to replace the Centurion MBT, the Chieftain has been replaced by Challenger but variants on the basic design still continue in service. The Chieftain armoured repair and recovery vehicle (ARRV), the armoured vehicle-launched bridge (AVLB) and armoured vehicle Royal Engineers (AVRE) are based on the Chieftain Mk 5 and some are conversions of the MBT.

In the case of the AVLB, the turret was replaced with an armoured roof plate. The commander's hatch and the bridge-launching equipment was installed on the roof plate. Chobham armour is fitted to the hull for extra protection and the AVLB can carry either a folding No 8 bridge on the front of the hull that can span 22m or a No 9 bridge that is carried horizontally and can be swung vertically to be lain in front. It spans 12m.

To assist on a battlefield the AVLB carried a mine-clearing plough in front and towed a trailer carrying a Royal Ordnance Giant Viper mine-clearing system. These main tracked vehicles are not due for replacement by the Army for some years to come although some will be retired as defence cuts take their toll, but they represent what the British Army has to go to war with at the present time.