Chieftain tank
The Vickers MBT followed on from a 24-tonne 20-pdr gunned tank design intended for export. This would be as well equipped as a Centurion but substantially cheaper and with eight Vickers Vigilant anti-tank missiles it would be as effective. However, with the introduction of the 105 mm L7 gun into the British, US and German tank designs, this light tank would have been less powerful while too large for the reconnaissance role, and so a new design was required. With armour twice that of the light tank design, it would still be 12 tonnes lighter than Centurion and hence more mobile. The design would use the new engine and transmission of the Chieftain tank then being developed. The development coincided with an agreement with India in 1961 to produce a tank design and help set up a factory there to produce it.