|Given names:||Vladimir Vasiliyevich||Viktor Petrovich|
|Spacecraft (Launch):||Soyuz T-4||Soyuz T-4|
|Launchtime:||19:00 UTC||19:00 UTC|
|Spacecraft (Landing):||Soyuz T-4||Soyuz T-4|
|Landingtime:||12:37 UTC||12:37 UTC|
|Mission duration:||74d 17h 37m||74d 17h 37m|
|Given names:||Vyacheslav Dmitriyevich||Boris Dmitriyevich|
Launch from the Baikonur Cosmodrome; landing 125 km east of Dzheskasgan.
Following a one day solo flight Soyuz T-4 docked with Salyut 6 on March 13, 1981. Docking with Salyut 6 delayed after the onboard Argon computer determined it would occur outside of radio range with the TsUP. The cosmonauts became the fifth and final resident crew of the Salyut 6 space station.
In mid-May 1981, Vladimir Kovalyonok and Viktor Savinykh replaced the Soyuz T-4 probe with a Salyut drogue. This may have been an experiment to see if a Soyuz-T docked to a space station could act as a rescue vehicle in the event that an approaching Soyuz-T equipped with a probe experienced docking difficulties and could not return to Earth.
Visiting crews were: Interkosmos missions Soyuz 39 on March 23, 1981 and Soyuz 40 on May 15, 1981, resulting in common science research onboard the station. One of the first mission objectives of this crew was, to unload the earlier launched Progress 12 spacecraft. Meteorological studies from the Bermuda triangle were conducted too.
Last update on March 30, 2013.