Challenger 2

The FV4034 Challenger 2 is a British main battle tank (MBT) in service with the armies of the United Kingdom and Oman. It was designed and built by the British company Vickers Defence Systems (now known as BAE Systems Land & Armaments).^[5]

Vickers Defence Systems began to develop a successor to Challenger 1 as a private venture in 1986. A £90 million deal for a demonstrator vehicle was finalised in January 1989. In June 1991, the Ministry of Defence placed a £520 million order for 140 vehicles, with a further 268 ordered in 1994. Production began in 1993 and the unit's tanks were delivered in July 1994, replacing the Challenger 1. The tank entered service with the British Army in 1998, with the last delivered in 2002. It is expected to remain in service until 2035. The Royal Army of Oman ordered 18 Challenger 2s in 1993 and a further 20 tanks in November 1997.

The Challenger 2 is an extensive redesign of the Challenger 1. Although the hull and automotive components seem similar, they are of a newer design and build than those of the Challenger 1 and only around 3% of components are interchangeable.^[6] The tank's drive system provides a 550 km range, with a maximum road speed of 59 km/h. It has a four-man crew.

The Challenger 2 is equipped with a 120-millimetre (4.7 in) 55-calibre long L30A1 tank gun,^[7] the successor to the L11 gun used on the Chieftain and Challenger 1. Uniquely among NATO main battle tank armament, the L30A1 is rifled, because the British Army continues to place a premium on the use of high explosive squash head (HESH) rounds in addition to armour-piercing fin-stabilized discarding-sabot armour-piercing rounds. The Challenger 2 is also armed with a L94A1 EX-34 7.62 mm chain gun and a 7.62 mm L37A2 (GPMG) machine gun. Fifty eight main armament rounds and 4,200 rounds of 7.62 mm ammunition are carried.

The Challenger 2 is considered to be one of the best protected tanks in the world.^[8] The turret and hull are protected with second generation Chobham armour (also known as Dorchester). However, on one occasion, in August 2006, during the post-invasion stage of the Iraq War 2003 an RPG-29 was fired at a Challenger 2 that was climbing over a ramp, the front underside hull armour of the tank which was not augmented with an explosive reactive armour package was damaged, the tank subsequently returned to base under its own power and was quickly repaired and back on duty the following day.^[9][10] As a result, the explosive reactive armour package was replaced with a Dorchester block and the steel underbelly lined with armour as part of the 'Streetfighter' upgrade as a direct response to this incident. To date, the only time the tank has ever been seriously damaged during operations, was by another Challenger 2 in a 'blue on blue' (friendly fire) incident.

It has seen operational service in Bosnia, Kosovo and Iraq.

History

The Challenger 2 is the third vehicle of this name, the first being the A30 Challenger, a Second World War design using the Cromwell tank chassis with a 17-pounder gun. The second was the Persian Gulf War era Challenger 1, which was the British army's main battle tank (MBT) from the early 1980s to the mid-1990s.

Vickers Defence Systems began to develop a successor to Challenger 1 as a private venture in 1986. Following the issue of a Staff Requirement for a next-generation tank, Vickers formally submitted its plans for Challenger 2 to the Ministry of Defence (MoD). Secretary of State for Defence George Younger announced to the House of Commons that Vickers would receive a £90 million contract for a demonstrator vehicle, a deal that was finalised in January 1989.^[11] The demonstration phase contained three milestones for progress, with dates of September 1989, March 1990, and September 1990. At the last of these milestones, Vickers was to have met 11 key criteria for the tank's design.^[11]

In June 1991, after competition with other tank manufacturers' designs (including the M1A2 Abrams and the Leopard 2 (Improved)), the MoD placed a £520 million order for 127 MBTs and 13 driver training vehicles. An order for a further 259 tanks and 9 driver trainers (worth £800 million) was placed in 1994. Oman ordered 18 Challenger 2s in 1993 and a further 20 tanks in November 1997.

Production began in 1993 at two primary sites: Elswick, Tyne and Wear and Barnbow, Leeds, although over 250 subcontractors were involved. The first tanks were delivered in July 1994.

The Challenger 2 successfully completed its Reliability Growth Trial in 1994. Three vehicles were tested for 285 simulated battlefield days. Each day consisted of:

• 27 km (17 mi) of on-road travel
• 33 km (21 mi) of off-road travel
• 34 main armament rounds fired
• 1,000 7.62 MG rounds fired
• 16 hours weapon system operation
• 10 hours main engine idling
• 3.5 hours main engine running

Challenger 2 Tank of the Royal Scots Dragoon Guards (Squadron D) during live fire training exercises on Bergen-Hohne Training Area (Germany)

An equally important milestone was the In-Service Reliability Demonstration (ISRD) in 1999. 12 fully crewed tanks were tested at the Bovington test tracks and at Lulworth Bindon ranges. The tank exceeded all staff requirements.

The Challenger 2 entered service with the British Army in 1998 (with the 2nd Royal Tank Regiment in Germany), with the last delivered in 2002. It is expected to remain in service until 2035. It serves with the Queen's Royal Hussars, the King's Royal Hussars and the Royal Tank Regiment, each of which is the tank Regiment of an Armoured Infantry Brigade. Under Army 2020, only three Challenger 2 Tank Regiments will remain: the Queen's Royal Hussars, the King's Royal Hussars and the Royal Tank Regiment; in addition, a single Army Reserve regiment, The Royal Wessex Yeomanry, will provide Armoured Resilience.

Deliveries of the Challenger 2 to Oman were completed in 2001.

The Trojan minefield breaching vehicle and the Titan bridge-laying vehicle based on the chassis of the Challenger 2 were shown in November 2006; 66 are to be supplied by BAE Systems to the Royal Engineers, at a cost of £250 million.^[12]

A British military document from 2001 indicated that the British Army would not procure a replacement for the Challenger 2 because of a lack of foreseeable conventional threats in the future.^[13] However, IHS Jane's 360 reported on the 20 September 2015 that following discussions with Senior Army Officers and Procurement Officials at DSEI 2015, as well as the head of the British Army, General Sir Nick Carter, that the British Army was looking at either upgrading the Challenger 2 or outright replacing it. Sources confirmed that the future of the MBT was being considered at the highest levels of the Army. This stemmed from the British Army's concern with the new Russian T-14 Armata main battle tank and the growing ineffectiveness of the ageing L30 rifled gun and its limited suite of ammunition. Further, it was confirmed that numerous armoured vehicle manufacturers had discussions with the MoD about a potential replacement for the Challenger 2.^[14] Shortly after, the British Army decided that purchasing a new tank would be too expensive and chose to proceed with a Challenger 2 life extension project (LEP).^[15]

Design

Armament

A Challenger 2 firing its main gun during an exercise. The round is visible to the left of the smoke cloud

Close-up of muzzle showing rifling

A row of Challenger II on a firing range at BATUS, Canada

The Challenger 2 is equipped with a 120-millimetre (4.7 in) 55-calibre long L30A1 tank gun,^[7] the successor to the L11 gun used on Chieftain and Challenger 1. The gun is made from high strength Electro Slag Remelting (ESR) steel with a chromium alloy lining and, like earlier British 120 mm guns, it is insulated by a thermal sleeve. It is fitted with a muzzle reference system and fume extractor, and is controlled by an all-electric control and stabilisation system. The turret has a rotation time of 9 seconds through 360 degrees.

Uniquely among NATO main battle tank armament, the L30A1 is rifled and along with its predecessor, Royal Ordnance L11A5, the only Third Generation Main Battle Tank Guns to use a rifled barrel. This is because the British Army continues to place a premium on the use of high explosive squash head (HESH) rounds in addition to Armour-piercing fin-stabilized discarding-sabot rounds. HESH rounds have a longer range (up to 8 kilometres or 5 miles further) than APFSDS, and are more effective against buildings and thin-skinned vehicles.^[16]

Forty-nine main armament rounds are carried in the turret and hull; these are a mix of L27A1 APFSDS (also referred to as CHARM 3), L31 HESH and L34 white phosphorus smoke rounds, depending on the situation. As with earlier versions of the 120 mm gun, the propellant charges are loaded separately from the shell or KE projectile. A combustible rigid charge is used for the APFSDS rounds, and a combustible hemispherical bag charge for the HESH and Smoke rounds. An electrically fired vent tube is used to initiate firing of the main armament rounds. (The main armament ammunition is thus described to be "three part ammunition", consisting of the projectile, charge and vent tube.) The separation of ammunition pieces also aids in ensuring lower chances of ammo detonation.

The Challenger 2 is also armed with a L94A1 chain gun EX-34 7.62 mm chain gun coaxially to the left of the main gun, and a 7.62 mm L37A2 (GPMG) machine gun mounted on a pintle on the loader's hatch ring. 4,200 rounds of 7.62 mm ammunition are carried. The Challenger can also mount a remote weapons system bearing a 7.62 mm L37A2 (GPMG) machine gun, a 12.7mm heavy machine gun or a 40mm automatic grenade launcher.^[17]

Fire control and sights

Close up view of a Challenger 2

The digital fire control computer from Computing Devices Co of Canada contains two 32-bit processors with a MIL STD1553B databus, and has capacity for additional systems, such as a Battlefield Information Control System.

The commander has a panoramic SAGEM VS 580-10 gyrostabilised sight with laser rangefinder. Elevation range is +35° to −35°. The commander's station is equipped with eight periscopes for 360° vision.

The Thermal Observation and Gunnery Sight II (TOGS II), from Thales, provides night vision. The thermal image is displayed on both the gunner's and commander's sights and monitors. The gunner has a stabilised primary sight using a laser rangefinder with a range of 200 m (660 ft) to 10 km (6.2 mi). The driver's position is equipped with a Thales Optronics image-intensifying Passive Driving Periscope (PDP) for night driving and a rear view thermal camera.

Protection

Challenger II with armour upgrades to the sides of the turret, skirts, bar armour to rear. Smoke grenade launchers visible on turret front. Counter-IED ECM antennas are on the platform on the turret, and additional ECM equipment overhangs the left and right front fenders.

The Challenger 2 is one of the most heavily armoured and best protected tanks in the world.^[8] The turret and hull are protected by second generation of Chobham armour (also known as Dorchester), the details of which are classified but which is said to be more than twice as strong as steel. Crew safety was paramount in the design, using a solid state electric drive for its turret and gun movement, thus removing the traditional risk of hydraulic rupture into the crew compartment. Explosive reactive armour kits are also fitted as necessary along with additional bar armour. The nuclear, biological and chemical (NBC) protection system is located in the turret bustle. The tank's shape is also designed with stealth technology to reduce radar signature.

On each side of the turret are five L8 smoke grenade dischargers. The Challenger 2 can also create smoke by injecting diesel fuel into the exhaust manifolds.

Drive system

A Royal Scots Dragoon Guards Challenger II climbing an obstacle during a training exercise 17 Nov 2008, in Basra, Iraq

The tank's drive system comprises:

• Engine: Perkins 26.6 litre CV12 diesel engine delivering 1,200 hp (890 kW).
• Gearbox: David Brown TN54 epicyclical transmission (6 fwd, 2 rev.).
• Suspension: second-generation hydrogas.
• Track: William Cook Defence hydraulically adjustable double-pin.
• Maximum speed: 37 mph (60 km/h) on road); 25 mph (40 km/h) cross country
• Range: 280 mi or 450 km on road); 156 mi (250 km) cross country, on internal fuel

As of 2013, the British Army has, at various events featuring the Challenger 2, begun to state the range of 550 km.^[3] They have also publicly stated a maximum road speed of 59 km/h while equipped with 15 tons of additional modules.^[3]

Crew and accommodation

The British Army maintained its requirement for a four-man crew (including a loader) after risk analysis of the incorporation of an automatic loader suggested that auto-loaders reduced battlefield survivability. Mechanical failure and the time required for repair were prime concerns.

Similar to every British tank since the Centurion, and most other British AFVs, Challenger 2 contains a boiling vessel (BV) for water, which can be used to brew tea, produce other hot beverages and heat boil-in-the-bag meals contained in field ration packs.^[18] This BV requirement is general for armoured vehicles of the British Armed Forces, and is unique to the armed forces of the UK and India.

Operational history

The Challenger 2 had been used in peacekeeping missions and exercises before, but its first combat use came in March 2003 during the invasion of Iraq. 7th Armoured Brigade, part of 1st Armoured Division, was in action with 120 Challenger 2s around Basra. The type saw extensive use during the siege of Basra, providing fire support to the British forces and knocking out multiple enemy tanks, mainly T-54/55s. The problems that had been identified during the large Saif Sareea II exercise, held 18 months earlier, had been solved by the issuing of Urgent Operational Requirements for equipment such as sand filters and so during the invasion of Iraq the tank's Operational availability was improved.

A Challenger 2 crosses into Iraq, 2003

During the 2003 invasion of Iraq, the Challenger 2 tanks suffered no tank losses to enemy fire, although one was penetrated by an IED. This was, at the time, unprotected by Dorchester armour. The driver was injured. In one encounter within an urban area, a Challenger 2 came under attack from irregular forces with machine guns and rocket propelled grenades. The driver's sight was damaged and, while attempting to back away under the commander's directions, the other sights were damaged and the tank threw its tracks entering a ditch. It was hit directly by 14 rocket propelled grenades from close range and a MILAN anti-tank missile.^[20] The crew survived, remaining safe within the tank until it was recovered for repairs, the worst damage being to the sighting system. It was back in operation six hours later, after repairs had been done. One Challenger 2 operating near Basra survived being hit by 70 RPGs in another incident.^[21]

In August 2006 south east of al-Amarah, southern Iraq, an RPG-29 capable of firing a tandem-charge penetrated the frontal armour of a Challenger 2 commanded by Captain Thomas Williams of The Queens's Royal Hussars. The tank, which had already been hit by 10-15 RPGs, small arms and sniper fire, was attempting to draw fire away from another callsign that had become stricken. Its driver, Trooper Sean Chance, lost part of his foot in the blast; two more of the crew were slightly injured. Chance was able to reverse the vehicle 1.5 mi (2.4 km) to the regimental aid post despite his injuries. The incident was not made public until May 2007; in response to accusations that crews had been told the tank was impervious to the insurgents weapons, the MoD said "We have never claimed that the Challenger 2 is impenetrable."^[9][10] Since then, the explosive reactive armour has been replaced with a Dorchester block and the steel underbelly lined with armour as part of the 'Streetfighter' upgrade as a direct response to this incident.

Two Challenger 2s have been damaged in combat, but only one has been destroyed:

• 25 March 2003: A friendly fire ("blue-on-blue") incident in Basra in which one Challenger 2 of the Black Watch Battlegroup (2nd Royal Tank Regiment) mistakenly engaged another Challenger 2 of the Queen's Royal Lancers after detecting what was believed to be an enemy flanking manoeuvre on thermal equipment. The attacking tank's second HESH round hit the open commander's hatch lid of the QRL tank sending hot fragments into the turret, killing two crew members. The strike caused a fire that eventually led to an explosion of the stowed ammunition, destroying the tank. It remains the only Challenger 2 to be destroyed on operations.^[22]
• 6 April 2007: in Basra, Iraq, a shaped charge from an IED penetrated the underside of a tank resulting in the driver losing three of his toes and causing minor injuries to another soldier.^[23]

An upgraded Challenger II with added explosive reactive armour panels, manufactured by Rafael Advanced Defense Systems^[24]

To help prevent incidents of this nature happening again, Challenger 2s have been upgraded with a new passive armour package, including the use of add-on armour manufactured by Rafael Advanced Defense Systems of Israel.^[24] When deployed on operations the Challenger 2 is now normally upgraded to TES (Theatre Entry Standard), which includes a number of modifications including armour and weapon system upgrades.

Upgrades and variants

CLIP/CLEP

The Challenger Lethality Improvement Programme (CLIP) was a programme to replace the current L30A1 rifled gun with the smoothbore Rheinmetall 120 mm gun currently used in the Leopard 2A6. The use of a smoothbore weapon would have allowed Challenger 2 to use NATO standard ammunition developed in Germany and the US. This includes tungsten-based kinetic energy penetrators, which do not have the same political and environmental objections as depleted uranium rounds. The production lines for rifled 120 mm ammunition in the UK have been closed for some years, so existing stocks of ammunition for the L30A1 are finite.^[25] In 2009, a new HESH round manufactured in Belgium has been trialled. This means that the Challenger 2 now has available a new Tungsten FIN and HESH rounds, if and when required, which secures a line of ammunition for its 55 calibre rifled main gun, the L30, when required in the future.

Challenger II fitted with 120 mm smoothbore gun for trials

A single Challenger 2 was fitted with the L55 and underwent trials in January 2006.^[26] The smoothbore gun is the same length as the L30A1, and is fitted with the rifled gun's cradle, thermal sleeve, bore evacuator and muzzle reference system. Early trials apparently revealed that the German tungsten DM53 round was more effective than the depleted-uranium CHARM 3.^[8] The ammunition storage and handling arrangements will need to be changed to cater for the single-piece smoothbore rounds, instead of the separate-loading rifled rounds. In 2006, a figure of £386 million was estimated to fit all Challengers in the British Army with the Rheinmetall 120 mm gun.^[25]

Other improvements have also been considered, including a regenerative NBC protection system.^[27] In addition several Challenger 2s had the pintle mounted GPMG on the loader's crew hatch replaced with a remote controlled turret, allowing the loader to operate the weaponry without having to expose himself to enemy fire.

In May 2007, the Ministry of Defence's Future Systems Group invited BAE to tender for the Challenger 2 Capability Sustainment Program (C2 CSP), which combined all upgrades into one programme. However, by mid-2008, the programme was in danger of slipping, or even being cancelled, as a result of defence budget shortfalls.^[28]

In July 2013, it was confirmed that the Challenger II Life Extension Programme is in the concept stage and will be in initial gate by 2014.,^[29] this later slipped to early 2015. In June 2014, it was stated that not all of the 227 Challenger 2s may be modified to CLEP standard and the smoothbore cannon had been dropped.^[30]

By the January 14, 2016 closing date for PQQ in the life extension programme BAE Systems, General Dynamics UK and Lockheed Martin UK had responded, the procurement process is expected to take two years with a commencement decision taken in 2019. By this time the £700m programme had been further refined to a goal of extending the life of the tank to 2035 and adressing obsolence issues such as turret subsytems and optics, with the exclusion of barrel replacement and the programme may be applied to the inventory of Oman too. At the same time a separate two year contract was awarded to BAE and Krauss Maffei Wegmann to develop an update to the bridging variant in part to address the increase in weight of the Challenger II from 62.5t to 75t arising from upgrades made during the Iraq campaign.^[31] A Royal Tank Regiment Newsletter dated December 2015 stated that the LEP includes managing to curb obsolescence in several turret systems – including TI sights, the Fire Control Computer (FCC) and electronic architecture in turret. Improved technology will be integrated as a new system on the platform, which will deliver more accurate engagements at range and improved FCC power, meaning that CR2 will remain a battle winning asset out to the extended out of service date. Parallel work strands will provide extensions to virtual training systems, deliver improved Live Fire Monitoring Equipment (LFME) and work is ongoing to develop improved 120mm ammunition natures.^[32]

Titan

TITAN Bridge Launcher with No.12 Bridge at Salisbury Plain

The Titan armoured bridge layer is based on aspects of the Challenger 2 running gear and will replace the Chieftain Armoured Vehicle Launched Bridge (ChAVLB). The Titan came into service in 2006 with the Royal Engineers, with 33 in service. Titan can carry a single 26-metre long bridge or two 12-metre long bridges. It can also be fitted with a bulldozer blade.

Trojan

Trojan AVRE

The Trojan Armoured Vehicle Royal Engineers is a combat engineering vehicle designed as a replacement for the Chieftain AVRE (ChAVRE). It uses the Challenger 2 chassis, and carries an articulated excavator arm, a dozer blade, and attachment rails for fascines. Entering service in 2007, 33 were produced.

Challenger 2E

The Challenger 2E is an export version of the tank. It has a new integrated weapon control and battlefield management system, which includes a gyrostabilised panoramic SAGEM MVS 580-day/thermal sight for the commander and SAGEM SAVAN 15 gyrostabilised day/thermal sight for the gunner, both with eyesafe laser rangefinder. This allows hunter/killer operations with a common engagement sequence. An optional servo-controlled overhead weapons platform can be slaved to the commander's sight to allow operation independent from the turret.

The power pack has been replaced by a new 1,500 hp (1,100 kW) EuroPowerPack with transversely mounted MTU MT 883 diesel engine coupled to Renk HSWL 295TM automatic transmission. The increase in vehicle performance is significant. The smaller volume but more powerful power pack incorporates as standard a cooling system and air-intake filtration system proved in desert use. The free space in the hull is available for ammunition stowage or for fuel, increasing the vehicle's range to 550 km (340 mi).

BAE announced in 2005 that development and export marketing of 2E would stop. This has been linked by the media to the failure of the 2E to be selected for the Hellenic Army in 2002, a competition won by the Leopard 2.^[33]

CRARRV

CRARRV on display at Salisbury Plain

The Challenger Armoured Repair and Recovery Vehicle (CRARRV) is an armoured recovery vehicle based on the Challenger 1 hull and designed to repair and recover damaged tanks on the battlefield. It has five seats but usually carries a crew of three soldiers from the Royal Electrical And Mechanical Engineers (REME), of the recovery mechanic and vehicle mechanic/technician trades. There is room in the cabin for two further passengers (e.g. crew members of the casualty vehicle) on a temporary basis.

The size and performance are similar to the MBT, but instead of armament it is fitted with:

• A main winch with 50 tonnes-force pull in a 1:1 configuration or 98 tonnes-force pull using an included pulley in a 2:1 configuration and anchor point on the vehicle, plus a small auxiliary winch to aid in deploying the main winch rope.
• Atlas crane capable of lifting 6,500 kg (14,300 lb) at a distance of 4.9 m (16 ft) (this is sufficient to lift a Challenger 2 power pack).
• In order to improve the flexibility and supplement the transportation power packs around the battlefield, the British Army procured a quantity of dedicated CRARRV High Mobility Trailers (CRARRV HMT). Each CRARRV HMT enables a CRARRV to transport a single (Challenger, Titan or Trojan) power pack or two Warrior power packs by altering the configuration of dedicated fixtures and attachment of fittings.
• Dozer blade to act as an earth anchor/stabiliser, or in obstacle clearance and fire position preparation.
• Large set of recovery and heavy repair tools including a man portable ultrathermic cutting system with an under water cutting capability and a man portable welding solution.

The design prototype is on display at The REME Museum of Technology in Arborfield, Berkshire.

Operators

Map of Challenger 2 operators.

•  United Kingdom: British Army 408 delivered (227 still in service, including 59 used for training or held in reserve)^[34]
•  Oman: Royal Army of Oman 38 delivered

See also

• List of armoured fighting vehicles

Tanks of comparable role, performance and era

• Ariete Italian main battle tank
• Type 99 tank Chinese main battle tank
• AMX Leclerc French main battle tank
• Leopard 2 Germain main battle tank
• Merkava Israeli main battle tank
• T-90 Russian main battle tank
• M1 Abrams US main battle tank
• K1 88-Tank South Korean main battle tank
• K2 Black Panther South Korean main battle tank

Notes

References

External links

Wikimedia Commons has media related to Challenger 2 tanks.

• British army Challenger 2 webpage