The FV4034 Challenger 2 (MoD designation "CR2") is a third generation British main battle tank (MBT) in service with the armies of the United Kingdom, Oman, and Ukraine.

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.

[citation needed] While the British Chieftain was heavily armed and armoured, its engine and suspension were considerably subpar compared to its contemporaries, leading to poor cross-country performance and a lack of maneuverability.

It also proved only marginally more reliable than the Chieftain, which was considered unreliable and a maintenance problem in the field, and the lack of significant improvement was much to the annoyance of the British Army.

Initial studies by the British Army invariably selected the Leopard 2, which was protected as well as Challenger but had much better mobility and used the smoothbore 120 mm gun that would give it commonality with other NATO forces.

[19] After some supportive lobbying by Baron Young, the Thatcher government chose to proceed with the Vickers entry in December 1988, giving it the official name Challenger 2.

[25] Both batches ordered by Oman contain notable differences from the UK version: a larger cooling group and rear towing eyes, running gear and bazooka plates similar to Challenger 1, and a loader's Browning 0.5 Calibre M2 Heavy Machine Gun.

[28] 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 the limited types of ammunition supported.

[28] Shortly after, the British Army decided that purchasing a new tank would be too expensive and chose to proceed with the Challenger 2 Life Extension Project (LEP).

[34] After the Russian invasion of Ukraine in 2022, the then British Prime Minister, Boris Johnson, declined Ukrainian requests for Challenger 2 tanks to be part of the military aid packages arranged by the United Kingdom and other NATO countries.

[35] In April 2022, Johnson and his German counterpart Olaf Scholz stated that both Western European allies would withhold their MBTs from the war.

These tanks were the first Western MBTs offered to Ukraine, supplementing donations of Western manufactured infantry fighting vehicles, armoured personnel carriers, and self-propelled artillery;[38][39][40] A number of other countries have subsequently announced that they would supply Ukraine with Western-manufactured MBTs; specifically the American M1 Abrams and German-made Leopard 1 and Leopard 2.

It uses a solid state electric drive for turret and gun motion, instead of hydraulic systems that can leak fluid into the crew compartment.

The type saw extensive use during the siege of the city, providing fire support to the British forces and knocking out Iraqi tanks, mainly T-54/55s.

[citation needed] The tanks deployed to Iraq were "desertised" in an effort to avoid the difficulties that had been identified in Challenger 2 during Exercise Saif Sareea II in Oman 18 month earlier.

In one encounter within an urban area, a Challenger 2 came under attack from irregular forces with machine guns and rocket propelled grenades (RPGs).

Since 2017, the UK has regularly deployed Challenger 2 tanks, alongside Warrior Infantry Fighting Vehicles, to Estonia as part of Operation Cabrit.

The two squadrons of tanks currently deployed, form part of the British contribution to the NATO Enhanced Forward Presence multinational battlegroup in the Baltics.

[75] In August 2024, British news media reported that Challenger 2 tanks were participating in Ukraine's Kursk Oblast incursion.

[77] The third claimed kill used a six second video clip posted on social media of a FPV drone striking a Challenger 2 parked in a tree line near the driver’s position.

[74][77][78] A fourth Challenger 2 tank was destroyed south of Malaya Loknya during the incursion on 5 January 2025 after a Russian FPV drone struck the gun mantlet.

The use of a smoothbore weapon would have allowed Challenger 2 to use NATO standard ammunition, including tungsten-based kinetic energy penetrators which do not have the same political and environmental objections as depleted uranium rounds.

[85] The HAAIP programme, awarded to BAE Systems, was intended to apply a common engine and suspension standard to Challenger 2, the DTT, CRARRV, Titan and Trojan, improving reliability.

The proposed CV12 upgrade by Caterpillar Defense would fit electronically controlled common rail fuel injection and introduce engine health monitoring (HUMS).

[103] In 2005, the MoD recognised a need for a Capability Sustainment Programme (CSP) to extend the service life of the Challenger 2 into the mid-2030s and upgrade its mobility, lethality and survivability.

The turret also received modifications to improve the speed of traverse and to provide greater space as well as regenerative braking to generate and store power.

[132] In August 2023, photos appeared of Challenger 2s in Ukrainian service featuring top-mounted slat armor, similar to those found on Russian vehicles used in the conflict, primarily to protect from UAV attacks.

The power pack has been replaced by a new 1,500 hp (1,100 kW) EuroPowerPack with a transversely mounted MTU MT883 diesel engine coupled to Renk HSWL 295TM automatic transmission.

However, the MoD confirmed that the information was in fact still classified, and that if Gaijin were to disseminate the tank's specifications, they would be liable to prosecution under the Official Secrets Act.

[148] Many of the pre-production prototype Challenger 2 vehicles are on display in the United Kingdom: In 2021, the then UK Minister for Defence Procurement, Jeremy Quin, acknowledged in a written answer, that were no current plans to dispose of a production vehicle to a museum, but that the UK MoD were aware that The Tank Museum intend to secure one for their collection.