The British Challenger 2 Tank

The British Challenger 2 Tank Background

The British Chieftain had served the Royal Armoured Corps as the most advanced tank of its day. It was the first tank to mount a 120mm main gun, which was also a calibre Length 55, something many countries still aspire too. However a replacement capable of being fitted with Chobham composite armour was sought after nearly 20 years service, called the Chieftain replacement program.

The British FV4211 aka the aluminium Chieftain was the first to be fitted with Chobham aka Burlington, but the project was cancelled. The UK entered into a new joint project with Germany called FMBT. The project did not see any working prototypes like the FV4211 had, but the FMBT project was cancelled.

The UK started a new project called the MBT80, which focused on the development of the firepower of the Chieftain replacement since FV4211 had rectified the issues with adding Chobham armour to a new tank. Only 2 ATR was built, but as no final designs were completed the project ended.

However the British Army could ill afford to wait until the early 90’s, which was the earliest predicted time scale it would take for the establishment to complete the development process for a replacement for the Chieftain. The Royal Ordnance Factory in Leeds had started production of an improved Chieftain design for Iran in the early 80’s called the Shir 2, which was capable of being equipped with the new composite armour, which was now called Chobham armour. However with the Iranian Revolution the order for the Shir 2 was cancelled, but with a number of modifications it was accepted in to service with the British Army as the Challenger in 1983 as a stop gap.

The British Armies tank doctrine had always been survivability through superior firepower and armoured protection, viewing mobility as the least important. Both the US with its Abrams and Germany with its Leopard 2, value firepower and mobility over armoured protection for survivability, which was reflected in their designs and the reason both vehicles were rejected as the replacement for the Chieftain.


The British Challenger 2 Tank Development

Challenger 2

In 1986 ROF Leeds and the Challenger production line were acquired by Vickers Defence Systems, which later became Alvis Vickers and is now known as BAE Systems Land. Vickers Defence Systems submitted a design, which was a modified Challenger hull, but only 5% of the components of the new design were compatible with the Challenger, as the new design had over 150 modifications including a brand new turret. A £90 million fixed-price contract to undertake a demonstration phase was awarded, which was to last until the end of September 1990. By August 1989, work started on building the nine prototypes, which were to also demonstrate that both a depleted uranium projectile and a new charge system could be developed for the Royal Ordnance 120mm CHARM gun.

The VDS new design was chosen as the British Armies new MBT and replacement for their Chieftain fleet, designated the Challenger 2 FV4034. VDS were awarded the contract worth £520 million to produce 140 tanks In June 1991, which included 13 training vehicles. Their production started in 1993 and the first delivery’s to the British Army were made on the 16th of May 1994.

The original idea by the MOD of a mixture of Challenger 1’s and 2’s within the British Army were dropped and VDS received a further order in July 1994 to build an additional 259 Challenger 2’s and over 280 of the Challenger 1’s were sold to Jordan. The Challenger 2 AKA “CR2” entered service in 1998 with the Royal Scots Dragoon Guards in Germany.


The British Challenger 2 Tank Operational History

The Challenger 2’s first deployment was to the Former war savaged Yugoslavia. It provided fire support for UN security forces apart from one throwing a track and crashing through some poor families house it had a relatively quiet tour.

However the vehicle had been involved in Saif Sareea II, also known as “Operation Swift Sword II”, which was a major military exercise in September and October 2001 in Oman.

The 66 Challenger 2’s which contributed to the exercise suffered from poor reliability. This was not due to any inherent defect with the tank, but rather due to the failure of the Army to adequately ‘desertise’ the tanks. Lessons learnt led to some modifications to the 120 Challenger 2’s deployed to secure the South of Iraq, notably Basra during Telic 1.

The real test for the Challenger 2 came in Operation Telic 1, which is better known as the 2003 Invasion of Iraq.

During Telic 1 the Challenger 2 did not see as many tank on tank engagements as the Challenger 1 had during the Gulf War of 1991. Many of the Tank on Tank battles were abandoned Iraqi tanks, including the famous 14 on 14 documented tank battle. However it was used to spearhead all the assaults and raids into Basrah, noticibly Al Zubiah, to open up the south for the remainding British Forces.

Challenger 2 Street Fighter
The British Challenger 2 Tank – Late Iraq War

Telic 1 Challenger 2 history was best known for a Royal Scots Dragoon Guards tank throwing its tracks and getting stuck in a ditch, which was reportedly hit by 14 RPG variants and a MILAN anti-tank missile. The attack saw the sights on the vehicle destroyed, but the armour was un-penetrated and the crew walked away when the vehicle was recovered.

The term “blue on blue” refers to Fratricide, or an accidental attack on friendly forces. On the 25th of March one Challenger 2 engaged another Challenger with HESH rounds. HESH is a typical high explosive lobed round meaning its firing trajectory is a high arch making it at range a top attack weapon. 1 round hit the back decks of the tank injuring the crew and another hitting the top of the turret reportingly with an open commanders hatch. This vicious explosion and enormous heat cooked off the tanks ammunition consequently destroying the tank. tragically killing two crewman. This engagement remains the only Challenger 2 to be catastrophically killed on operations.

After Telic 1, the number of Challenger 2’s in theatre were reduced and moved to more of a security role rather than an aggressive war fighter. Often providing an armoured fist when striking into the city, as well as leading most convoys and providing a physical deterrent.

It was during this period in August 2006 that a Challenger 2 from the Queens Royal Hussars was struck by a deadly tandem charged RPG-29 anti-tank missile. Though there were various inaccurate reports on the web at the time, the missile dropped short, exploding on the ground sending shrapnel and blast up under the tank penetrating the then unprotected steel belly of the tank, The Driver; Trooper Sean Chance, lost three of his toes in that attack.

In April 2007 whilst on a security patrol in Basra, a Challenger 2 of the 2nd Royal Tank Regiment hit an Improvised Explosive device, this was a EFP = Explosively formed projectile designed to form a moulten jet of copper capable of penetrating through a lot of armour. This attack again was a belly attack. The driver, Trooper Stephen Shine boor the brunt of the blast as it tore through the floor of his drivers cab. The lower section of his left leg was damaged so badly doctors were forced to amputate above the knee. Steve still serves in the 2nd Royal Tank Regiment and was later deployed on Operation Herrick (Afghanistan). He also skies for the British Army Team (FEAR NAUGHT!!).

The Challenger 2 remained in Iraq until roughly 2009. For a number of years it operated at Squadron strength, which is just 14 vehicles. Many claim that as there were less Challenger 2’s than the US Abrams series deployed to Iraq, the Abrams would therefore take greater losses. After the invasion and during the “occupation” or Iraq, 14 Challenger 2’s and the CRARRV were out working almost every night and therefore were in greater demand than their Abrams cousin, which meant these Challenger 2 were still attacked regularly. Sadly 5% of the Abrams deployed were returned to the US as either heavily damaged or destroyed during this period.

Challenger 2
The British Challenger 2 Tank

The Challenger 2 had no losses, despite being attacked every night by the same enemy, with the same weapons. To say that British Forces did not receive the same intense level of attack, though on a smaller scale, is seen by British Forces as an insult.

The Combat Support vehicles based on the Challenger 2 have been deployed to Operation Herrick (Afghanistan) such as the CRARRV TROJAN and TITAN Armoured Vehicle Launch Bridge during the 2010 Operation Moshtarak.


The British Challenger 2 Tank Protection

The Challenger 2 uses the latest version of Chobham armour, which is referred to Dorchester, which is the name of the town where the armour is manufactured. Though many countries use composite armour, it is the bonding process and the matrix with which the composition (hence term composite) of ceramic materials is held in, that makes the Chobham series of armour more effective than that of other composite armour, as it keeps the ceramics under a certain tension and hardening them further. The CR2, like all tanks is made of steel. However the CR2’s is called Sheffield Steel, which is known as a crucible steel. This is a process used to remove impurities found in other steels, resulting in a superior quality.

Tank

An un-deployed Challenger 2 simply has its base Dorchester armour covering its hull and turret fronts. These are simply known as MBT’s or in the driver training world “Gun-tanks”. They are used through out the British Royal Armoured Corps for training and exercises, in Germany, Poland, Canada and the UK.

Up armoured

This is the term used by tank crews for adding additional modules to the area’s that in the event of a hit/strike will raise the crew survivability chance. Deployed Challenger 2’s will all be Up-armoured. The Up-armour development and evolution process can be broken down into tiers.

Tier 1 – Tanks sent to Kosovo in 2001 were up armoured with a single layer of modular slabs along the hull on both sides. These comprised of the latest Dorchester variant. Also fitted to the CR2 like CR1 before it was a Nose cone consisting of several dozen ERA bricks bolted on to the Glacis plate. Tier 1 was also used on those tanks deployed for the Invasion of Iraq in 2003, known as Operation Telic 1.

Tier 2 – This saw the addition of modules along the sides of the turret of tier 1 tanks during the later Op Telic’s as the risk and danger to the crew changed from traditional Anti-Tank weapons to a more generic IED threat.. This also saw the replacement of the distinct nose cone of ERA slabs to a massively heavy and thick nose cone of the latest Dorchester variant, This was a solid object containing no ERA.

Tier 3 – Additional armour was successfully trailed by the armoured trials and development unit Bovington, which included additional ERA slabs on top of the existing add-on armour slabs on the sides of the hull. This was hoped to reduce the regularity of replacing expensive and heavy add-on Dorchester slabs. This bought the weight of the Challenger 2 up to 74.95 tonnes!


The British Challenger 2 Tank Firepower

Challenger 2

The CR2 Main Armament is the L30, which is manufactured by BAE Systems Land Systems (formerly RO Defence). The L30 is rifled, giving the CR2 greater accuracy, as the rifling imparts a spin to the fired round which stabilizes it and prevents it from tumbling, as well as giving the CR2 the ability to fire heavier rounds. The 120mm L30 cannon is made from Electro Slag Re-melting steel (ESR) to lengthen the cannons life and increase its accuracy.

To quote one British CR2 crewman ” Thanks to the quality of the L30, the old issue of wearing down of the rifling through repeated firing is almost non-existent. On average we fire 450+ rounds a year on active vehicles during training exercises and we averaged 200 during Operation Telic 1. In all my years of service, I’ve never known an L30 to be replaced due to wearing of the rifling “.

He went on to say ” The L30’s rifled barrel is more than capable of firing and withstanding the ammunition required during a normal conventional operations training year and has done since 1998. When the recommended rates of fire are adhered to and the correct maintenance and service of the weapon system is carried out, the barrel has no disadvantage over that of a smoothbore “.

To initiate the firing sequence in the L30 CHARM3 120mm gun all 3 parts of ammunition must be in place, firstly the Projectile is loaded, followed by a bag charge of tightly wrapped cordite strips.

Then the breach is closed and a Vent Tube is automatically loaded inside a special chamber within the breach blocks. When the firing switch is pressed a small electrical charge is sent to the back of the vent tube and it is fired.

The Vent tube blasts a jet of fire through a special guide in the breach blocks and into the chamber via a small hole. this is then channelled into the back of the Bag charge which has a small built in bag of fine powder in its base.

Upon firing and recoil the empty Vent tube is ejected out the back of the breach and is caught by a cloth shield. Another Vent tube is then automatically loaded. and the loading sequence can begin once more.

Thou some may class the vehicle as using a three part ammo, the Vent Tubes are loaded into the breach in a magazine, so are not manually loaded with the projectile and charge by the operator during each loading sequence, therefore we still refer to the Challenger 2 as using 2 part ammo.

The Challenger 2 is capable of firing several types of ammunition:

Operational Natures –

1. Armour Piercing Fin-Stabilised Discarding Sabot (APFSDS for short) is the L27 CHARM3 and has a DU tip to avoid “mushrooming” on contact with the enemy armour. Tankies call this round “FIN”. The L14 propellant system is based on a rigid Combustible Case Charges (CCC for short) and loaded after the FIN.

2. High Explosive Squash Head (HESH for short) is a multi-functional round. When it impacts on a wall/armour, the explosive spreads on to the outer surface, known as a “pat” and then is detonated, which sends a shockwave through the armour blowing off an inner section known as a “Spalding”, which is the size of a plate and fly’s around the turret cooking off the ammo, cutting hydraulics and carving the crew up. The blast can also damage the sights, sensors, tracks and main gun inflicting either a firepower kill or mobility kill. Its extremely effective as a demolition round and anti-personnel. Its armed by the rifling of the L30 and requires a low m/v to form the pat, so is fired at a high trajectory to gain range using the L3A3 cordite stick charge.

3. White Phosphorous is used for Covering Withdrawals, Covering enemy positions and used as a Marker for Target/obstacle recognition. The L34 is the same size and weight as a HESH round and three are carried on a typical bomb load unless a specific reason is pre defined.

Training Natures –

1. DS/T (Discarding Sabot Training) DST to the crew. It is made of Tungsten and cheaper than the L27 CHARM3.

2. The HESH Training Round is Called SH/P “shuss Pee” to its crews, made from Portland Concrete and totally Inert, its size and weight is that same of what a HESH round is, 17.5kg

3. There is no White Phosphorous training round.

Challenger 2

A bomb load is made up of 33 FIN, 3 Smoke and 13 HESH. In a Sabre Troop the Troop leader can redistribute the HESH or Smoke about his 3 Tank Callsigns. Or choose to carry more HESH on his Tank (The Centre Callsign) This is called being “HESH Heavy” giving the Troop Corporal on his left and Troop Sergeant on his right more KE rounds ,as they are more likely to engage enemy tanks first.

For close encounters, the Challenger 2 is equipped with a co-axial Boeing 7.62mm chain gun, which is located to the left of the main gun. The loader has a 7.62mm GPMG L37A2 anti-air machine gun, mounted on the cupola.

Upgrading to the German L55 smoothbore

Challenger 2
The British Challenger 2 Tank with L55 smoothbore

There are two types of main guns used on tanks, rifled and smoothbore. Both have advantages and disadvantages. Rifling imparts a spin to the fired round which stabilizes its flight and prevents it from tumbling. This increases its range and accuracy compared to a smoothbore, which automatically starts to tumble as its left the muzzle.

The energy released from the combustion of the rounds charge builds up behind the round as it travels down the main gun. Some of the energy escapes through the grooving of the rifling. Energy doesn’t escape with a smoothbore, which requires a higher level of muzzle velocity to stop the round from tumbling. A number of tanks using shorter smoothbores are swapping to cal Length 55 main guns to increase muzzle velocity, AKA the L55. The increased length means that the round has further to travel down the barrel, which means the energy from the charge has longer to build up, pushing the round hard out of the muzzle, increasing its velocity. This then means the round takes longer to tumble and increases the range and accuracy as well as the punch to get through the enemies armour.

It was for this reason that a lot of people have mistakenly believed that the CR2 was swapping over to a L55 smoothbore. This is incorrect. The British do not name their main guns after their cal Length like the Germans, so people are unaware that the CR2 L30 main gun is a cal Length 55 and therefore already has a high muzzle velocity. The reason the British Army field tested the German L55 smoothbore was for a cost cutting exercise to purchase cheaper rounds.

It was found with previous generation rifled main guns, that as the round makes its way down the barrel it starts to wear down the rifling, shortening the main guns life, where as this wouldn’t happen on smoothbores, therefore it was found to be more cost effective to use smoothbores when operating large tank fleets, like the USA’s Abram and Germany’s Leopard 2, which totalled ten thousand plus during the Cold War and why both vehicles were equipped with smoothbores. This means there are more smoothbores and as such, a higher demand for the number of smoothbore rounds, which in turn drives down their production costs and makes them cheaper to purchase.

The Challenger 2 will not be fitted with the German L55 smoothbore Main Gun!!

Smoothbores use one part rounds and store these in one large box in the rear of the turret. Rifled uses 2 part. This means the non explosive part is kept in the turret and the explosive charge (2nd part) is kept separately in the hull. The field tests showed that the one part rounds did not fit in the existing storage set up and to fit a normal compliment of 1 part rounds would require a new turret, of which the cost would be higher than any savings made buying cheaper rounds, especially considering at the time some turrets were only four years old!

BAE did conduct some research in trying to move storage in the turret around, but only a maximum of six 1 part rounds could be stored. It’s for these reasons that the British Army are no longer pursuing the adoption of a smoothbore main gun.

Future supply chain of new ammunition

However TankNutDave has learnt that during 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 calibre Length 55 rifled main gun, the L30 when required in the future.


The British Challenger 2 Tank Fire Control Systems

Challenger 2

The digital fire control computer is supplied by Computing Devices Company (now General Dynamics – Canada). Both the Gunner and Commander have Primary Sights. They can both either switch between their day channels (magnification x4 and x10) or the channel from the Thermal Imaging Sight, which is called the “Thermal Imaging Sensor Head”. It has a magnification x4 and x11.5 and is also displayed on TV monitors AKA a display module. There is a display module at both the commanders and gunners station next to their PS’s. The 4Hz laser rangefinder (range 200m to 10km) can be operated on either channel through the PS or display module. All sights are gyro stabilised.

The commander’s cupola is equipped with eight periscopes which provide him with a 360° vision to check around the vehicle. The Gunner has a x1 magnification periscope so that he can traverse the turret and elevate the main gun whilst the vehicle is on the move and not engaging targets.

The CR2’s Hydrogas suspension gives it an increased stability for whilst firing on the move.


The British Challenger 2 Tank Digitalisation

The main complaint about the CR2 was its lack of secure modern digital communications. This has been resolved through out 2006 with the introduction of the Bowman tactical, digital communications system with a built in GPS receiver, which paved the way for the Challenger 2 to be fitted and integrated into the BOWMAN, with the Platform Battlefield Information System Application (PBISA) from General Dynamics UK. It operates a program called Combat, which displays a digital battlefield map known as “Situational Awareness” displaying the other Challenger 2/British Army AFV’s thanks to the new BOWMAN’s GPS receiver, which also provides live updates as the AFV’s are on the move. The system integrates the commander’s display, inertial navigation system, digitisation processing computer and driver’s display panel, giving the commander and crew exceptional Situational Awareness and allows other British Army AFV’s to send E-mails between each other and send instant Contact Reports back to HQ.

The system also allows the commander to point at a spot on the digital map and send a go to order to the drivers display, which shows him an arrow and range to that spot, as well as the best route.


The British Challenger 2 Tank Mobility

Challenger 2
The British Challenger 2 Tank Powerpack

The CR2’s 1200bhp is generated by a Perkins CV12 26 litre diesel engine. The gearbox is a David Brown TN54 epicyclical transmission with 6 forward and 2 reverse gears. It has a 450km on road and 250km cross country capability. Many publications claim the Challenger 2 has a top road speed of 59km/h, however this only a requirement …..

The engine is electronically governed to 3200 RPM and that in 6th gear is it capable of 70km/h (road speed and cross-country) thanks to its Hydropneumatic suspension AKA Hydrogas. It uses a nitrogen springing medium, which is approximately six times more flexible than conventional steel as used in TorsionBar suspension. This allows the CR2 to maintain a relatively high speed as the nitrogen springing easily absorbs irregularities in the terrain it crosses in comparison to TorsionBar.

The TA (Track adjuster) is a hydraulically extended wheel on an Exocentric axle fixed to a ram operated by the driver. This allows him to adjust the tightness of the track and avoid any unnecessary stress on the William Cook Defence double-pinned tracks. It also increases the ease and maintenance of the tracks to get them off.

New Hydrogas suspension for 2010….

The British Armies Armoured Trials and Development Unit have also been trialling a new Hydrogas Suspension system to increase the vehicles mobility in response to the addition of the new modular armour during 2010.

There have also been unconfirmed rumours to the possibility of a new 1500hp engine, but this is purely rumour, however it should not be forgotten that the Challenger 2 is compatible with the 1500hp MTU EuroPowerPack and gave the best cruising range and lower fuel consumption in comparative tests with the Leopard 2A5 and Abrams M1A2.


The British Challenger 2 Tank Street Fighter

Challenger 2

Since late 2007 & early 2008, the Challenger 2 has been going though an-upgrade program called ‘Street Fighter’. It has seen a number of new systems being fitted to CR2’s heading to Iraq and will soon be standard on all CR2’s. A new CCTV camera has been fitted in the rear of the vehicle, so that the driver can see what he is doing as he reverses, rather than the commander using his sights and giving instructions. The driver now has a new forward-looking thermal sight. It has received additional modular armour on the sides of the turret to complement the existing modular armour on the sides of the hull. It’s also been fitted with new armour on the belly of the hull. Another new system is the Remote Weapons Station. This is controlled from within the vehicle and equipped with a thermal imaging camera and replaces the loaders L7, so he is not exposed to use it. It can be mounted with either a 7.62mm or 50 cal MG or 40mm GMG (grenade machine gun).


Defence Cuts announced for 2010

The British Armed Forces have taken a pounding as a result of the report titled “The Strategic Defence and Security Review” of 2010. The review has been interpreted by other online and media sources, that the British Army Challenger 2 fleet should be dramatically reduced to 130.

Sources close to TankNutDave have confirmed that the first 40 Challenger 2’s have been gutted of vital systems and chopped up for scrap metal by civilian contractors in the summer of 2011 and that an un-disclosed number of such vehicles in an identical state (the turrets are held to the hulls with straps) remain in storage ready to be also scrapped.

However this incorrect. The report recommends “reduce our holdings of Challenger 2 main battle tanks by around 40%. This is consistent with our assessment of likely adversaries and future types of conflict.”. As of 2014 the British Army Challenger 2 fleet stands at 227 vehicles.


Challenger 2 Life Extension Programme

The Challenger 2 LEP is as of 2015 still in the development stages. Its main goal is to seek the replacement of obsolete components that are no longer built and possible upgrades (this does not include the fitting of a L55 smoothbore gun). This is currently being completed by BAE Systems.

Its findings will be presented to the British Armies capability branch at Headquarters Army at Andover, Hampshire. A decission will be made on what replacement and any upgrades can be covered in the services equipment procurement and support budgets. This could effect the number of Challenger 2 that benefit from the program.

In early 2015, BAE announced that it had won a £50 million contract for engineering support for the British Army armour fleet including Challenger 2. The contract merges current support contracts.


The British Challenger 2 Tank Export Market

Challenger 2

The Challenger 2 has suffered two major blows in foreign sales. The first has been its late development. The M1A1 had impressed Arabic/Middle East and North African customers during the Gulf War, so were already ordering and taking delivery’s before the CR2 entered production. The second was the end of the Cold War. Without the need for huge tank fleets anymore, Germany and the Netherlands found themselves with the cost of maintaining vehicles they no longer needed so could offer 2nd hand Leopard 2 A4’s at a very reduced cost (Germany donated Poland theirs!) and of course the added bonus of a surplus of cheaper rounds.

The Challenger 2 E is the most recent model and specifically designed for export. It has a different 1500 bhp compact engine, increasing the fuel capacity and the range to 550km. It also has different on board computers and imaging equipment, but on the whole it’s designed for harsh environmental and climactic conditions, such as desert warfare.

Its only export customer so far has been Oman, who placed a contract worth £140 million in July 1993, and a second contract in November 1997 worth £100 million to buy a total of 38 Challenger 2’s, four Challenger Armoured Repair and Recovery Vehicles and two driver training tanks.

The Greek Trials

In late 1998, the Hellenic Army (Greece) conduct tests of the firepower and mobility (not the armoured protection) of the French Leclerc, the Leopard 2 A5 (they used the Swedish Strv 122!) Russian T-80U, Ukrainian T-84 and the British CR2E.
The Greeks scored the Leopard 2A5 – 78.65% the M1A2 Abrams – 72.21% the Leclerc – 72.03%; and the CR2E – 69.19%

The Leopard 2A5 was the only one with a demonstrated deep fording capability, while the M1A2 had the best firing results during hunter/killer target engagements. The 1500hp MTU EuroPowerPack of the Leclerc and CR2E gave the best cruising range and lower fuel consumption. The Greeks were already operating the Leopard 2 A4 (reduced cost 2nd hand) and in 2000 the Leopard 2 A6 was selected as their new principal MBT.

When the CR2 was returned the FCS was tested and found in good order. It was found that the main gun had soot and debris in the barrel. This was because the Greeks had been supplied with the old Challenger 1’s L23 APFSDS for the trials and as such the old L14A2 case charge, which was a modified for desert weather L14A1 and had been so hurriedly manufactured that WNC-supplied L8 combustible cases were modified to meet urgent deliveries for the Gulf War. It was the old L14A2 case charges that had been responsible for the debris in the barrel and fouling the shots fired in Greece. The CR2 is no longer marketed.