T-80UD is a variant of the T-80U Main Battle Tank, fitted with a diesel engine in place of the high performance gas turbine. The original T-80 with a gas turbine was produced in 1976. The T-80UD with conventional diesel engine was introduced in 1985 and entered service with the Soviet Army in 1987. Design of the T-80UD is similar to the T-80U except the powerplant. Development of this MBT commenced in the mid 1970s. Production of the T-80UD commenced in Ukraine in 1987. About 500-800 of these MBTs were built, and it was planned as the primary MBT of the Soviet Army. However with the collapse of the Soviet Union its production ceased in 1991. These tanks are currently in service with Russia and Ukraine. A number of Ukrainian T-80UDs were exported to Pakistan in the late 1990s. Armour protection of the T-80UD includes composite armour with built-in explosive reactive armour blocks. The vehicle is fitted with NBC protection and automatic fire suppression systems
