Soyuz 25

Soyuz 25
COSPAR ID1977-099A Edit this at Wikidata
SATCAT no.10401
Mission duration2 days, 44 minutes, 45 seconds
Orbits completed32
Spacecraft properties
Spacecraft typeSoyuz 7K-T
ManufacturerNPO Energia
Launch mass6,860 kilograms (15,120 lb)
Crew
Crew size2
MembersVladimir Kovalyonok
Valery Ryumin
CallsignФотон (Foton - "Photon"
Start of mission
Launch dateOctober 9, 1977, 02:40:35 (1977-10-09UTC02:40:35Z) UTC
RocketSoyuz-U
Launch siteBaikonur 1/5[1]
End of mission
Landing dateOctober 11, 1977, 03:25:20 (1977-10-11UTC03:25:21Z) UTC
Landing site185 kilometres (115 mi) NW of Tselinograd
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee altitude198.5 kilometres (123.3 mi)
Apogee altitude258.1 kilometres (160.4 mi)
Inclination51.66 degrees
Period88.66 minutes
Soyuz programme
(Crewed missions)

Soyuz 25 (Russian: Союз 25, Union 25) was an October, 1977, Soviet crewed space flight, the first to the new Salyut 6 space station, which had been launched 10 days earlier. However, the mission was aborted when cosmonauts Vladimir Kovalyonok and Valery Ryumin failed to engage the docking latches of the station despite five attempts. Lacking sufficient fuel to attempt a dock at the other end of the station and with battery power for only two days, they returned to Earth.[2]

The failure led to a new rule whereby every crew had to have at least one person aboard who had previously flown in space.[3]

  1. ^ "Baikonur LC1". Encyclopedia Astronautica. Archived from the original on 2009-04-15. Retrieved 2009-03-04.
  2. ^ The mission report is available here: http://www.spacefacts.de/mission/english/soyuz-25.htm
  3. ^ Cite error: The named reference clark was invoked but never defined (see the help page).