Soyuz 31
Bykowski (above) and Jähn (below) | |
| Operator | Soviet space program |
|---|---|
| COSPAR ID | 1978-081A |
| SATCAT no. | 11010 |
| Mission duration | Capsule: 67 days, 20 hours and 12 minutes Original crew: 7 days, 20 hours and 49 minutes |
| Spacecraft properties | |
| Spacecraft type | Soyuz 7K-T |
| Manufacturer | NPO Energia |
| Launch mass | 6,800 kg (15,000 lb) |
| Crew | |
| Crew size | 2 |
| Launching | Valery Bykovsky Sigmund Jähn |
| Landing | Vladimir Kovalyonok Aleksandr Ivanchenkov |
| Callsign | Ястреб (Yastreb - "Hawk") |
| Start of mission | |
| Launch date | 26 August 1978, 14:51:30 UTC |
| Rocket | Soyuz-U |
| Launch site | Baikonur 1/5 |
| End of mission | |
| Landing date | 2 November 1978, 11:04:17 UTC |
| Landing site | 140 km (87 mi) SE of Dzhezkazgan |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Low Earth |
| Perigee altitude | 196.8 km (122.3 mi) |
| Apogee altitude | 259.9 km (161.5 mi) |
| Inclination | 51.64 degrees |
| Period | 88.81 minutes |
| Docking with Salyut 6 | |
| Docking port | Aft port |
| Docking date | 28 August 1978, 16:37:37 UTC |
| Undocking date | 7 September 1978, 16:37:37 UTC |
| Time docked | 10 days |
| Redocking with Salyut 6 | |
| Redocking port | Front port |
| Redocking date | 7 September 1978, 16:37:37 UTC |
| Unredocking date | 2 November 1978, 11:04:17 UTC |
| Time redocked | 55 days, 18 hours and 26 minutes |
Soyuz 31 (Russian: Союз 31, Union 31) was a 1978 Soviet crewed space flight to the Salyut 6 space station. It was the seventh mission to and sixth successful docking at the orbiting facility. The Soyuz 31 crew were the second to visit the long-duration Soyuz 29 resident crew.
Soyuz 31 carried Valery Bykovsky and Sigmund Jähn, the first German cosmonaut, into space. They swapped Soyuz craft with the long-duration crew and returned to Earth in Soyuz 29, the resident crew returned to Earth in Soyuz 31.