Background: Challenger 1

The Challenger replaced the Chieftain in the early 1980s. It came about as a result of a series of unconnected events across the world.

The roots of the vehicle go back to an order from Iran in 1974 for a number of modified and upgraded Chieftains, named the Shir, of which there were two variants planned. The former (Shir 1) was an upgraded Chieftain, and the other (Shir 2) was for a more modified version. Modifications for the Shir 2 were principally made to the weak points of the Chieftain: the engine and suspension. The Leyland engine was replaced by a Perkins diesel and the suspension (Horstmann bogie) was given a longer travel to improve cross-country performance. With hindsight, this can be seen as the Challenger 1 running gear.

In a roughly parallel move, the British Army was seeking to develop a Chieftain replacement utilising the new composite Chobham armour, as well as upgrades to the rest of the Chieftain systems. The project was known as the MBT 80 and was pitched against the US M1 Abrams and the German Leopard II. When it became clear that the armour would not be ready in time, this project was cancelled and the quest was on for a replacement.

In 1979, following the Iranian revolution and the departure of the Shah, the Shir order was cancelled. Thankfully for Vickers and the British government, the Jordanians stepped into the gap and took over the order for the Shir 1 which they subsequently named Khalid 1.

The British also spotted the as yet undelivered Shir 2. The obvious political and commercial appeal of a home-grown successor to the Chieftain meant that it became the new MBT, Challenger. Although accepted in late 1982, it was as an interim solution and conditional upon the successful addressing of a series of issues around the sights, generator drives and other equipment. Between 1983 and 1990, around 420 were delivered.

Compared to its predecessor, the Challenger 1 was a major improvement. Its new engine was much more powerful and much more reliable. The Hydragas suspension featured a long wheel travel, resulting in a far better crew ride than that of the old Horstmann type of the Chieftain (and the Conqueror before that). The desirability of this feature had been known since the days of the Christie suspension of the 1930s (see T34) but achieving a solution to the perceived penalties had meant that the British tendency was to remain with other systems.

‘Stop-gap’ (as Challenger 1 might be regarded) or not, it went on to acquit itself well in service. During the First Gulf War in 1900-91, when British Challengers destroyed over 300 Iraqi AFVs without loss.

Aside from the British Army, the only other nation to operate the Challenger 1 has been Jordan.

Challenger 2:

Since the Challenger 1 was generally seen as a stopgap (albeit a very competent one), it was clear to all, especially the manufacturer Vickers, that a longer term replacement would be necessary.

They began a private development of what would become the Challenger 2 in 1986, while deliveries of the Challenger 1 were still taking place (a similar story to the Tiger 1 and Tiger 11 from 50 years earlier).

Despite the commonality of the name, the two tanks are really very different, sharing only about 5% of their components. The Perkins engine is retained, as is the 120mm rifled gun. However these carry over items are modified. Perhaps most importantly the Challenger 2 featured the so-called Chobham armour. This classified development is a form of composite said to offer better protection aganist both kinetic and hollow charge projectiles, than steel armour.

Initial trials fully vindicated the claims of the manufacturer and exceeded the specifications laid down by the Army. Challenger 2 started entering service in 1998.

Challenger 2 has seen service in various peace-keeping operations and also the Second Gulf War. During the latter conflict, one Challenger 2 was hit by 14 RPGs at close range and a MILAN anti tank missile. All the crew remained in the tank and were unharmed. The tank was recovered, repaired and back in action 6 hours later.

Alone among the larger NATO nations, the UK stayed with a rifled 120mm gun. The main competitor is the Rheinmetall L55 smooth bore 120mm fitted to the Leopard 2, firing fin-stabilised rounds. The question mark over the furutre of rifled 120mm ammunition and the desirability of NATO commonality has led to the Rheinmetall gun being trialled and installed. Although the gun fitted the existing installation, changes had to be made to accommodate the large, fixed case ammunition (as opposed to the separate ammunition of the earlier gun). An export version (Challenger 2E) with an MTU powerpack has also been trialled. This offers more power from a physically smaller engine. Engineer, recovery and bridgelaying derivatives have also been produced. There are no current plans to develop a successor to Challenger 2.