Soyuz T-4

Soyuz T-4

COSPAR ID	1981-023A
SATCAT no.	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	Baikonur 1/5
End of mission
Landing date	26 May 1981, 12:37:34 (1981-05-26UTC12:37:35Z) UTC
Landing site	125 kilometres (78 mi) E Dzhezkazgan
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 with Salyut 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-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.^[1] 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; its crew were the last to have inhabited Salyut 6.^[2]

Crew

Position	Crew
Commander	Vladimir Kovalyonok Third and last 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.^[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 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.^[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 of Dzhezkazgan, Kazakh SSR.^[1]

See also

• List of human spaceflights to Salyut space stations
• List of Salyut expeditions

References

• v
• t
• e

Soyuz programme

• List of Soyuz missions
• List of Soviet human spaceflight missions
• List of Russian human spaceflight missions

Main topics

• Soyuz (rocket family)
• Soyuz (spacecraft)
• Baikonur Cosmodrome
  • Site 1/5
  • Site 31/6
• Soyuz abort modes
• Cosmonaut ranks and positions

Past missions
(by spacecraft type)

Soyuz 7K-OK (1966–1970)	Kosmos 133† Soyuz 7K-OK No.1† (uncrewed) Kosmos 140 Soyuz 1† Kosmos 186 188 212 213 238 Soyuz 2 (uncrewed) 3 4 5 6 7 8 9
Soyuz 7K-L1 (1967–1970) (Zond lunar programme)	Kosmos 146 154† Zond 1967A† 1967B† Zond 4 1968A† 1968B† 5 6 1969A† Zond-M 1† M 2† Zond 7 8 9 10
Soyuz 7K-L1E (1969–1970)	Soyuz 7K-L1E No.1† Kosmos 382
Soyuz 7K-LOK (1971–1972)	Soyuz 7K-LOK No.1† No.2†
Soyuz 7K-OKS (1971)	Soyuz 10† 11†
Soyuz 7K-T (1972–1981)	Kosmos 496 573 Soyuz 12 Kosmos 613 Soyuz 13 Kosmos 656 Soyuz 14 15† 17 18a† 18 20 (uncrewed) 21 23† 24 25† 26 27 28 29 30 31 32 (uncrewed landing) 33† 34 (uncrewed launch) 35 36 37 38 39 40
Soyuz 7K-TM (1974–1976)	Kosmos 638 672 Soyuz 16 19 (Apollo–Soyuz) 22
Soyuz 7K-S (1974–1976)	Kosmos 670 772† 869†
Soyuz-T (1978–1986)	Kosmos 1001† 1074 Soyuz T-1 (uncrewed) T-2 T-3 T-4 T-5 T-6 T-7 T-8† T-9 T-10a† T-10 T-11 T-12 T-13 T-14 T-15
Soyuz-TM (1986–2002)	Soyuz TM-1 (uncrewed) TM-2 TM-3 TM-4 TM-5 TM-6 TM-7 TM-8 TM-9 TM-10 TM-11 TM-12 TM-13 TM-14 TM-15 TM-16 TM-17 TM-18 TM-19 TM-20 TM-21 TM-22 TM-23 TM-24 TM-25 TM-26 TM-27 TM-28 TM-29 TM-30 TM-31 TM-32 TM-33 TM-34
Soyuz-TMA (2002–2012)	Soyuz TMA-1 TMA-2 TMA-3 TMA-4 TMA-5 TMA-6 TMA-7 TMA-8 TMA-9 TMA-10 TMA-11 TMA-12 TMA-13 TMA-14 TMA-15 TMA-16 TMA-17 TMA-18 TMA-19 TMA-20 TMA-21 TMA-22
Soyuz-TMA-M (2010–2016)	Soyuz TMA-01M TMA-02M TMA-03M TMA-04M TMA-05M TMA-06M TMA-07M TMA-08M TMA-09M TMA-10M TMA-11M TMA-12M TMA-13M TMA-14M TMA-15M TMA-16M TMA-17M TMA-18M TMA-19M TMA-20M
Soyuz MS (2016–present)	Soyuz MS-01 MS-02 MS-03 MS-04 MS-05 MS-06 MS-07 MS-08 MS-09 MS-10† MS-11 MS-12 MS-13 MS-14 (uncrewed test flight) MS-15 MS-16 MS-17 MS-18 MS-19 MS-20 MS-21 MS-22 (uncrewed landing) MS-23 (uncrewed launch) MS-24

Current missions

• MS-25

Future missions

• 2024
  • MS-26

Uncrewed missions are designated as Kosmos instead of Soyuz; exceptions are noted "(uncrewed)".
The † sign designates failed missions. Italics designates cancelled missions.