Challenger is a development of the Centurion line / Cacique, modified to produce the two Shir / Iran had originally planned for service with the Iranian forces. After the Iranian Revolution the Shir Iran 2 project was taken by the British army and the end result was later renamed Challenger 1 Challenger. The main differences between Challenger and its predecessor are the driving force chief of Challenger, producing 1,200 hp at 2,300 rpm, much more powerful than the Chieftain engine, and the Chobham armor, which gives very high levels of protection against weapons tank.
The Challenger 1 has been in service with the British army since 1983. It was originally produced by Royal Ordnance Factory in Leeds, which was acquired by Vickers Defence Systems in 1986. It plans to begin withdrawing the Challenger service in 1998 and must be completely replaced by Challenger 2 in 2002. Challenger 1 took part in Operation Desert Storm where the Iraqi forces did not have a single vehicle out of combat while Challenger destroyed about 300 Iraqi tanks.