| COSPAR ID | 1981-023A |
|---|---|
| SATCATno. | 12334 |
| 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 | |
| Crew size | 2 |
| Members | Vladimir Kovalyonok Viktor Savinykh |
| Callsign | Photon |
| Start of mission | |
| Launch date | 12 March 1981, 19:00:11 (1981-03-12UTC19:00:11Z) UTC |
| Rocket | Soyuz-U |
| Launch site | Baikonur1/5 |
| End of mission | |
| Landing date | 26 May 1981, 12:37:34 (1981-05-26UTC12:37:35Z) UTC |
| Landing site | 125 kilometres (78 mi) EDzhezkazgan |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Low Earth |
| Perigee altitude | 201 kilometres (125 mi) |
| Apogee altitude | 250 kilometres (160 mi) |
| Inclination | 51.6 degrees |
| Period | 88.7 minutes |
| Docking withSalyut 6 | |
| Docking date | 13 March 1981, 20:33 (1981-03-13UTC20:33Z) UTC[1] |
| Undocking date | 26 May 1981, 09:20 (1981-05-26UTC09:21Z) UTC[1] |
Soyuz programme (Crewed missions) | |
Soyuz T-4 was aSoviet space mission which launched the crew of Salyut 6 EO-6, the sixth and final long-duration crew of theSalyut 6 space station. It was launched on 12 March 1981 and docked with the station the next day.[1] During their stay, the EO-6 crew was visited bySoyuz 39 andSoyuz 40. Soyuz T-4 returned to Earth on 26 May 1981; its crew were the last to have inhabited Salyut 6.[2]
| Position | Crew | |
|---|---|---|
| Commander | Vladimir Kovalyonok Third and last spaceflight | |
| Flight engineer | Viktor Savinykh First spaceflight | |
| Position | Crew | |
|---|---|---|
| Commander | Vyacheslav Zudov | |
| Flight engineer | Boris Andreyev | |
The docking with Salyut 6 was delayed after the Soyuz's onboard Argon computer determined it would occur outside radio range with the TsUP.[3] 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.[1] This freed the remaining docking port for the arrival of theSoyuz 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.[1]
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 ofDzhezkazgan,Kazakh SSR.[1]
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| Past missions (by spacecraft type) |
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Uncrewed missions are designated asKosmos instead ofSoyuz; exceptions are noted "(uncrewed)". The † sign designates failed missions.Italics designates cancelled missions. | |||||||||||||||||||||||||||
