books.google.co.uk - The successor to the Chieftain from the 1960's, work began in 1976 on development of a new MBT specifically for the Iranian army, who needed a more capable tank than the Chieftain to suit their climatic and geographical conditions. However, once the revolution occurred in 1979 the British army was reluctantly...http://books.google.co.uk/books/about/Challenger_Main_Battle_Tank_1982_97.html?id=6Pkeug7XXmUC&utm_source=gb-gplus-shareChallenger Main Battle Tank 1982-97
