Soyuz-T
The Soyuz-T was the third generation of the Soyuz spacecraft and operated from 1979 to 1986. The T designation stood for "transport", reflecting its primary role ferrying crews to and from space stations. The design was based on the second-generation Soyuz 7K-T and incorporated experience gained from the Military Soyuz program and the Soyuz 7K-TM used for the Apollo–Soyuz Test Project.
Soyuz-T introduced several major improvements over earlier models. It was the first Soyuz to use solid-state electronics and featured an upgraded onboard computer intended to reduce the docking difficulties encountered on previous missions. Solar panels returned to the design, enabling autonomous flight for up to 11 days, and the spacecraft adopted a new propulsion system, the KTDU-426. Unlike preceding versions, Soyuz-T could carry three cosmonauts wearing pressure suits.