Challenger 2 FV4034 Challenger 2 is a British main battle tank ( MBT ) currently 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 and Armaments ) . The manufacturer advertises it as the world ' s most reliable main battle tank . As of January 2008 , two Challenger 2s have been damaged in combat , and one destroyed by another Challenger 2 in a friendly fire incident . Challenger 2 is an extensive redesign from Challenger 1 , the MBT from which it was developed . It uses the basic hull and automotive parts of its predecessor but all other components are new . Fewer than 5 % of components are interchangeable . Challenger 2 has now replaced Challenger 1 in service with the British Army and is also used by the Royal Army of Oman . It has seen operational service in Bosnia , Kosovo and Iraq ( 2003 – present ) . During the 2003 invasion of Iraq the Challenger 2 tanks operating in the Gulf suffered no total losses to enemy fire . In one engagement a Challenger survived 14 hits from rocket - propelled grenade s and one MILAN anti tank missile . History . 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 pdr 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 ( later Alvis Vickers , now BAE Systems Land 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 £90 million contract for a demonstrator vehicle , a deal that was consummated in January 1989 . 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 . 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 is known to have consisted of : 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 . Challenger 2 entered service with the British Army in 1998 ( with the Royal Scots Dragoon Guards in Germany ) , with the last delivered in 2002 . It is expected to remain in service until 2035 . It serves with the Royal Scots Dragoon Guards , the Royal Dragoon Guards , the Queen ' s Royal Hussars , the King ' s Royal Hussars and the 2nd Royal Tank Regiment , each of which is the tank unit of an armoured or a mechanised brigade . One squadron of the 1st Royal Tank Regiment uses Challenger 2 in a training / demonstration role . Deliveries of 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 £250M . Design . Armament . Challenger 2 is equipped with a 120 mm ( 4 . 7 - inch ) 55 calibre long L30A1 tank gun , 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 stabilization system . The turret has a rotation time of 9 seconds through 360 degrees . 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 APFSDS armour - piercing 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 . 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 . ) Contrary to speculation , the use of three - part ammunition rather than the NATO standard single part cased ammunition does not reduce the rate of fire of Challenger 2 ; in fact , a loader can often sustain a higher rate of fire than tanks firing single part ammunition , with or without auto - loaders . The Challenger 2 is also armed with a L94A1 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 . Fire Control and sights . 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 , for example 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 to 10 km . The driver ' s position is equipped with a Thales Optronics image - intensifying Passive Driving Periscope ( PDP ) for night driving . Defence . Challenger 2 is one of the most heavily armoured and best protected tanks in the world . The turret and hull are protected with second generation Chobham armour ( also known as Dorchester ) the details of which are still classified . Although Chobham armour is classified , the military claims it to be twice as strong as steel . Explosive reactive armour ( ERA ) kits are also fitted as necessary . The nuclear , biological and chemical ( NBC ) protection system is located in the turret bustle . On each side of the turret are five L8 smoke grenade dischargers . Challenger 2 can also create smoke by injecting diesel fuel into the exhaust manifolds . 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 . Like every British tank since the Centurion , and most other British AFVs , Challenger 2 contains a boiling vessel ( BV ) also known as a kettle or " bivvie " for water which can be used to brew tea , produce other hot beverages and heat boil - in - the - bag meals contained in ration packs . This BV requirement is general for armoured vehicles of the British Armed Forces , and is one such requirement almost unique to the Armed forces of the UK . Operational usage . Challenger 2 had already 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 tanks saw extensive use during the siege of Basra , providing fire support to the British forces . The tank ' s availability was excellent and the problems that were identified during the large Saif Sareea II exercise , which took place eighteen months earlier , were solved by the issuing of Urgent Operational Requirements for equipment such as sand filters . In one encounter within the 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 eight rocket propelled grenades from close range and a MILAN anti - tank missile , and was under heavy small arms fire for hours . The crew survived remaining safe within the tank until the tank was recovered for repairs , the worst damage being to the sighting system . It was back in operation six hours later after the repairs . One Challenger 2 operating near Basra survived being hit by 70 RPGs in another incident . There have been only two Challenger 2s damaged in combat and one destroyed : To help prevent incidents of this nature happening again , Challenger 2s have been upgraded with a new passive armour package . When deployed on operations the Challenger 2 is now normally upgraded to TES ( Theatre Entry Standard ) , this includes a number of modifications including armour and weapon system upgrades . Upgrades and variants . Challenger Lethality Improvement Programme . The Challenger Lethality Improvement Programme is a programme to replace the current L30A1 rifled gun with the 120 mm Rheinmetall L55 smoothbore gun currently used in the Leopard 2 A6 . The use of a smoothbore weapon allows Challenger 2 to use NATO standard ammunition developed in Germany and the US . This includes more lethal tungsten - based kinetic energy penetrator s , 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 . A single Challenger 2 was fitted with the L55 and underwent trials in January 2006 . 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 . 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 gun . Other improvements have also been considered , including a regenerative NBC protection system . 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 . Challenger 2E . 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 with a new 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 powerpack 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 . 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 . CRARRV . The " Challenger Armoured Repair and Recovery Vehicle " ( CRARRV ) is an armoured recovery vehicle based on the Challenger 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 Vehicle Mechanic and Recovery Mechanic 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 : Titan . 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 is a combat engineering vehicle , styled as an AVRE for Armoured Vehicle , Royal Engineers in British Army parlance , designed as a replacement for the " Chieftain AVRE " ( ChAVRE ) . It uses the Challenger 2 chassis , and will carry an articulated excavator arm , a dozer blade , and attachment rails for fascine s . Like Titan , 33 are intended to reach service .