Back Союз 15 Bulgarian সয়ূজ ১৫ Bengali/Bangla Soiuz 15 Catalan Sojuz 15 Czech Sojus 15 German Soyuz 15 Spanish سایوز۱۵ Persian Sojuz 15 Finnish Soyouz 15 French Soiuz 15 Galician
 | |
| Mission type | Salyut 3 crew transport |
|---|---|
| Operator | Soviet space program |
| COSPAR ID | 1974-067A |
| SATCAT no. | 7421 |
| Mission duration | 2 days, 12 minutes |
| Orbits completed | 32 |
| Spacecraft properties | |
| Spacecraft | Soyuz 7K-T No.4 |
| Spacecraft type | Soyuz 7K-T/A9 |
| Manufacturer | OKB-1 |
| Launch mass | 6,570 kg (14,480 lb)[1] |
| Landing mass | 1,200 kg (2,600 lb) |
| Crew | |
| Crew size | 2 |
| Members | Gennady Sarafanov Lev Dyomin |
| Callsign | Дунай (Dunay - "Danube") |
| Start of mission | |
| Launch date | 26 August 1974, 19:58:05 UTC |
| Rocket | Soyuz 11A511 |
| Launch site | Baikonur 1/5[2] |
| End of mission | |
| Landing date | 28 August 1974, 20:10:16 UTC |
| Landing site | 48 km (30 mi) at the southwest of Tselinograd |
| Orbital parameters | |
| Reference system | Geocentric orbit[3] |
| Regime | Low Earth orbit |
| Perigee altitude | 254 km (158 mi) |
| Apogee altitude | 275 km (171 mi) |
| Inclination | 51.60° |
| Period | 89.60 minutes |
 Soviet stamp featuring Sarafanov and Dyomin (1974) | |
Soyuz 15 (Russian: Союз 15, Union 15) was an August 1974 crewed space flight which was to have been the second mission to the Soviet Union's Salyut 3 space station with presumably military objectives.[4]
Launched 26 August 1974, the Soyuz spacecraft arrived at the station, but cosmonauts Gennady Sarafanov and Lev Dyomin were unable to dock because the electronics in the Igla docking system malfunctioned. Without sufficient fuel for prolonged attempts at manual docking, the mission had to be abandoned. The cosmonauts powered down all nonessential systems in the Soyuz and waited until the next day for reentry.[5] The crew landed 28 August 1974. Analysis of the launch window was cited by observers for concluding a flight of 19 to 29 days had been planned.[5]
In the event of the failure, official TASS statements merely claimed that the mission was intended to practice docking maneuvers with the Salyut 3 station.[4] They also said that a new automatic docking system was tested which would be used on future Progress transport craft.[5]
The failed mission exposed a number of serious design flaws in the Soyuz 7K-T spacecraft, namely its lack of reserve propellant and electrical power for repeated docking attempts. In addition, the Igla docking system was found to be in major need of improvement. Since it was impossible to carry out these changes before Salyut 3 finished its operating lifespan, they had to wait for future space stations. The backup spacecraft for the Soyuz 15 mission was placed in storage and later flown as Soyuz 20 despite being past its intended shelf life.
- ^ Cite error: The named reference
Displaywas invoked but never defined (see the help page). - ^ "Baikonur LC1". Encyclopedia Astronautica. Archived from the original on 15 April 2009. Retrieved 4 March 2009.
- ^ Cite error: The named reference
Trajectorywas invoked but never defined (see the help page). - ^ a b Clark, Phillip (1988). The Soviet Manned Space Program. New York: Orion Books, a division of Crown Publishers, Inc. ISBN 0-517-56954-X.
- ^ a b c Newkirk, Dennis (1990). Almanac of Soviet Manned Space Flight. Houston, Texas: Gulf Publishing Company. ISBN 0-87201-848-2.