Soyuz T-4

Soyuz T-4

Soyuz T-4
COSPAR ID 1981-023A[1]
SATCAT № 12334[1]
Mission duration 74 days, 17 hours, 37 minutes, 23 seconds
Orbits completed 1,178
Spacecraft properties
Spacecraft type Soyuz-T
Manufacturer NPO Energia
Launch mass 6,850 kilograms (15,100 lb)
Crew size 2
Members Vladimir Kovalyonok
Viktor Savinykh
Callsign Photon
Start of mission
Launch date 12 March 1981, 19:00:11 (1981-03-12T19:00:11Z) UTC
Rocket Soyuz-U
Launch site Baikonur 1/5
End of mission
Landing date Did not recognize date. Try slightly modifying the date in the first parameter. UTC
Landing site 125 kilometres (78 mi) E Dzhezkazgan
Orbital parameters
Reference system Geocentric
Regime Low Earth
Perigee 201 kilometres (125 mi)
Apogee 250 kilometres (160 mi)
Inclination 51.6 degrees
Period 88.7 minutes
Docking with Salyut 6
Docking date 13 March 1981, 20:33 (1981-03-13T20:33Z) UTC[2]
Undocking date Did not recognize date. Try slightly modifying the date in the first parameter. UTC[2]

Soyuz programme
(Manned missions)
← Soyuz T-3 Soyuz 39

Soyuz T-4 was a Soviet space mission which launched the crew of Salyut 6 EO-6, the sixth and final long-duration crew of the Salyut 6 space station. It was launched on 12 March 1981 and docked with the station the next day.[2] During their stay, the EO-6 crew was visited by Soyuz 39 and Soyuz 40. Soyuz T-4 returned to Earth on 26 May 1981.


  • Crew 1
    • Backup crew 1.1
  • Mission parameters 2
  • Mission highlights 3
  • References 4


Position Crew
Commander Vladimir Kovalyonok
Third spaceflight
Flight Engineer Viktor Savinykh
First spaceflight

Backup crew

Position Crew
Commander Vyacheslav Zudov
Flight Engineer Boris Andreyev

Mission parameters

  • Mass: 6850 kg
  • Perigee: 201 km
  • Apogee: 250 km
  • Inclination: 51.6°
  • Period: 88.7 minutes

Mission highlights

The docking with Salyut 6 was delayed after the Soyuz's onboard Argon computer determined it would occur outside radio range with the TsUP. Despite this, the docking occurred successfully on 13 March 1981. The Progress 12 spacecraft was already docked to the station by the time the crew arrived, and they spent several days unloading the Progress before its undocking on 19 March.[2] This freed the remaining docking port for the arrival of the Soyuz 39/EP-9 crew on 22 March.

In mid-May, Kovalyonok and Savinykh replaced the spacecraft's 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.[2]

The EO-6 crew undocked from Salyut 6 on 26 May, leaving behind the Soyuz's orbital module. Soyuz T-4 landed over three hours later, touching down 125 kilometres (78 mi) east of Dzhezkazgan, Kazakh SSR.[2]


  1. ^ a b McDowell, Jonathan. "SATCAT". Jonathan's Space Pages. Retrieved 24 March 2014. 
  2. ^ a b c d e f "Soyuz T-4". Spacefacts. 24 November 2013. Retrieved 24 March 2014.