Soyuz 7K-T Credit - © Mark Wade

Following the disastrous Soyuz 11 flight, when the crew was killed by cabin depressurization, the 7K-OKS design was subjected to a complete redesign, resulting in the substantially safer 7K-T space station ferry. One crew position was eliminated, making it possible for the two crew members to wear pressure suits during dangerous phases of the flight. Batteries replaced the solar panels of the earlier configuration, to eliminate the chance of undeployed panels causing problems as was the case on Soyuz 1. Numerous minor changes were made to improve the basic safety and redundancy of the design. The 7K-T would safely fly 31 times until replaced by the Soyuz T in 1981.

Soyuz Guidance and Controls

The re-entry maneuver was normally handled automatically by radio command. Spacecraft attitude in relation to the local motion along the orbit was determined by sun sensors, infrared horizon sensors and ion gauges, which could detect the spacecraft's direction of motion by the greater velocity of ions impacting the spacecraft in the direction of motion.

The cosmonaut could however take manual control of the spacecraft and manually re-enter. This was done by using the ingenious Vzor periscope device. This had a central view and eight ports arranged in a circle around the centre. When the spacecraft was perfectly centered in respect to the horizon, all eight of the ports would be lit up. Alignment along the orbit was judged by getting lines on the main scope to be aligned with the landscape flowing by below. In this way, the spacecraft could be oriented correctly for the re-entry maneuver.

To decide when to re-enter, the cosmonaut had a little clockwork globe that showed current position over the earth. By pushing a button to the right of the globe, it would be advanced to the landing position assuming a standard re-entry at that moment.

This manual system would obviously only be used during daylight portions of the orbit. At night the dark mass of the earth could not have been lined up with the optical Vzor device. The automatic system would work day or night. However problems were found on Soyuz 1 when the ion gauges would not function in ion 'pockets' of low density in the re-entry maneuver portion of the orbit.

The Soyuz kept (to this day) the little globe and Vzor system. On the early model Soyuz, prior to the Soyuz T of the 1980's, there was no on-board inertial navigation system. To perform an orbital maneuver, the parameters for an orbital maneuver would be transmitted from the ground. When the time came for a maneuver, the spacecraft would align itself to the local vertical and direction of motion by the methods mentioned above (automatic or manual). Then three gyros would be spun up, the spacecraft maneuvered automatically or manually to the required attitude for the maneuver, and the main engine would fire automatically at the prescribed time to make the orbit change. There was a simple delta-v gauge showing the velocity change. Since the Soyuz thrust to weight was so low (around 0.06, or only half a meter per second) this meant the maneuvers could be handled manually without much error (on re-entry burns the practice was to count to five after the engine was supposed to shut off before overriding it!)

The Soyuz had always had very limited maneuver capability, a source of some embarrassment during the ASTP joint flight where the Apollo did most of the maneuvering. Not until the Soyuz T version was enough maneuvering fuel and the inertial navigation system available to allow rendezvous with non-co-operative objects (like the dead Salyut 7 station on the epic Soyuz T-15 flight) and to fly around objects for inspection (this was theoretically possible in the old models, but due to limited fuel or conservatism it was never demonstrated).

Crew Size: 2. Design Life: 3 days. Orbital Storage: 110 days. Typical orbit: 227 km circular orbit, 51.5 deg inclination. Length: 7.48 m (24.54 ft). Maximum Diameter: 2.72 m (8.92 ft). Habitable Volume: 11.00 m3. Mass: 6,800 kg (14,900 lb). Main Engine: KTDU-35. Main Engine Thrust: 4.089 kN (919 lbf). Main Engine Propellants: Nitric Acid/Hydrazine. Main Engine Propellants: 500 kg (1,100 lb). Main Engine Isp: 282 sec. Spacecraft delta v: 210 m/s (680 ft/sec). Electrical System: Batteries. Electric System: 0.84 average kW.

• Soyuz 7K-T BO.  Other Designations: Bytovoy otsek. Part of: Soyuz 7K-T. Class: Manned. Type: Spacecraft Module. Purpose: Living section.

  Lightweight male/female docking system with roller-type probe, internal transfer tunnel (Collar Length: 0.22 m. Probe Length: 0.50 m. Base Diameter: 1.35 m. Ring Diameter: 1.35 m). Igla automatic rendezvous and docking system with lightweight antennae, single-dish tower. Four windows, BO separated after retrofire.

  Length: 2.98 m (9.77 ft). Basic Diameter: 2.26 m (7.41 ft). Maximum Diameter: 2.26 m (7.41 ft). Habitable Volume: 5.00 m3. Mass: 1,350 kg (2,970 lb).

• Soyuz 7K-T SA.  Other Designations: Spuskaemiy apparat. Part of: Soyuz 7K-T. Class: Manned. Type: Spacecraft Module. Purpose: Reentry capsule.

  Post-Soyuz 11 modification for crew of two in spacesuits. Analogue sequencer and computers operate spacecraft. Off-line periscopes, no covers on portholes, standard touchdown rockets, improved parachute, and low-rate + one voice telemetry system. 20-45 kg of return payload in addition to crew.

  Crew Size: 2. Length: 2.24 m (7.34 ft). Basic Diameter: 2.17 m (7.11 ft). Maximum Diameter: 2.17 m (7.11 ft). Habitable Volume: 3.50 m3. Mass: 2,850 kg (6,280 lb). Crew mass: 255 kg (562 lb). Payload: 1,355 kg (2,987 lb). RCS Coarse No x Thrust: 6 X 98 N. RCS Propellants: H2O2. Expr24: 40. Main Engine Propellants: 45 kg (99 lb).

• Soyuz 7K-T PAO.  Other Designations: Priborno-agregatniy otsek. Part of: Soyuz 7K-T. Class: Manned. Type: Spacecraft Module. Purpose: Equipment-engine section.

  Soyuz 7K-OK basic PAO service module with pump-fed main engines and separate RCS/main engine propellant feed system. Solar panels deleted and spacecraft powered by batteries only.

  Length: 2.26 m (7.41 ft). Basic Diameter: 2.15 m (7.05 ft). Maximum Diameter: 2.72 m (8.92 ft). Mass: 2,700 kg (5,900 lb). RCS Coarse No x Thrust: 14 X 98 N. RCS Fine No x Thrust: 4 X 98 N. RCS Coarse Backup No x Thrust: 8 x 10 N. RCS Fine Backup No x Thrust: 4 x 10 N roll. RCS Propellants: H2O2. Main Engine: KTDU-35. Main Engine: 305 kg (672 lb). Main Engine Thrust: 4.089 kN (919 lbf). Main Engine Propellants: Nitric Acid/Hydrazine. Main Engine Propellants: 500 kg (1,100 lb). Main Engine Isp: 282 sec. Backup Main Engine Thrust: 4.030 kN (906 lbf). Electrical System: Batteries. Electric System: 0.50 average kW. Electric System: 18.00 kWh.

• 1970 February 9 - Salyut project begins. -
  Ministry of General Machine Building (MOM) Decree 105-41 'On creation of the DOS using Almaz as a basis' was issued.

• 1970 February 16 - Salyut crash program authorised. -
  Decree 57ss 'On creation of the DOS using Almaz as a basis' was issued.

• 1971 July 4 - Soyuz 11 failure investigation - Program: Lunar L3, Salyut. Flight: Soyuz 11. Launch Vehicle: N1.
  This was a very difficult time for TsKBEM. All work at the bureaus came to a complete halt after the loss of Soyuz 11 and N1 6L. Simultaneous expert commissions investigated the loss of N1 6L and Soyuz 11. TsKBEM was seen as responsible for every failure. A virtually legal process ensued to fix guilt. Every design decision was examined and questioned. Additional Details: Soyuz 11 failure investigation.

• 1972 January 1 - TsKBEM reorganised - Program: Lunar L3, Soyuz, Almaz. Launch Vehicle: N1, RT-2.
  TsKBEM was given a completely new structure as a result of the findings of the expert commissions on the disasters for the previous year, Mishin remained as the Chief Designer for the organisation, but each programme now had its own chief designer:
  • N1: Boris Dorofeyev
  • 8K98P solid propellant ICBM: Igor Sadovskiy
  • N1 payloads: Vladimir Brorov [check]
  • Soyuz 7K-TM, or Soyuz M, for Soyuz-Apollo: Konstantin Bushuyev
  • Soyuz 7K-T: Yuri Semenov
  • Soyuz 7K-S or Soyuz VI: Yevgeni Shabarov
  Additional Details: TsKBEM reorganised.

• 1972 June 26 - Cosmos 496 - Program: Salyut. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,675 kg (14,715 lb). Perigee: 176 km (109 mi). Apogee: 253 km (157 mi). Inclination: 51.50 deg. Period: 88.70 min. Duration: 9.95 days.
  Recovered July 6, 1972 13:54 GMT. Soyuz 7K-T redesign test.

• 1972 August 1 - Soyuz 12 / DOS 2 (cancelled) - Program: Salyut. Crew: Kubasov, Leonov. Flight: Soyuz 12 / DOS 2.
  Planned first mission to the Salyut DOS 2 space station. Cancelled after it was destroyed during launch.

• 1972 October 1 - Soyuz 13 / DOS 2 (cancelled) - Program: Salyut. Crew: Lazarev, Makarov. Flight: Soyuz 13 / DOS 2.
  Planned second mission to the Salyut DOS 2 space station. Cancelled after it was destroyed during launch.

• 1973 June 1 - Soyuz (Almaz) 12 (cancelled) - Program: Almaz. Crew: Artyukhin, Popovich. Flight: Soyuz (Almaz) 12.
  Planned first crew to the first Almaz space station. Cancelled after the loss of control of Almaz OPS 1 (Salyut 2) in orbit.

• 1973 June 1 - Soyuz 12 / DOS 3 (cancelled) - Program: Salyut. Crew: Kubasov, Leonov. Flight: Soyuz 12 / DOS 3.
  Planned first mission to the Salyut DOS 3 space station (Cosmos 557). Cancelled after it failed in orbit.

• 1973 June 15 - Cosmos 573 - Program: Salyut. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,675 kg (14,715 lb). Perigee: 191 km (118 mi). Apogee: 308 km (191 mi). Inclination: 51.60 deg. Period: 89.50 min. Duration: 2.00 days.
  Soyuz test flight. Recovered June 17, 1973 6:01 GMT. Soyuz 7K-T redesign test, probably using one of the spacecraft allocated to the failed Salyut 2 or Cosmos 557 stations.

• 1973 August 1 - Soyuz (Almaz) 13 (cancelled) - Program: Almaz. Crew: Demin, Sarafanov. Flight: Soyuz (Almaz) 13.
  Planned second crew to the first Almaz space station. Cancelled after the loss of control of Almaz OPS 1 (Salyut 2) in orbit.

• 1973 September 1 - Soyuz 13 / DOS 3 (cancelled) - Program: Salyut. Crew: Lazarev, Makarov. Flight: Soyuz 13 / DOS 3.
  Planned second mission to the Salyut DOS 3 space station (Cosmos 557). Cancelled after it failed in orbit.

• 1973 September 27 - Soyuz 12 - Program: Salyut. Crew: Lazarev, Makarov. Flight: Soyuz 12. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,720 kg (14,810 lb). Perigee: 306 km (190 mi). Apogee: 348 km (216 mi). Inclination: 51.00 deg. Period: 91.00 min. Duration: 1.97 days.
  Experimental flight for the purpose of further development of manned space craft Soyuz 7K-T modifications. After the Soyuz 11 disaster, the Soyuz underwent redesign for increased reliability. Two solo test flights of the new design were planned. Crews for the first flight were those already planned for the deferred follow-on missions to the failed DOS 2 and DOS 3 space stations.

• 1973 November 30 - Cosmos 613 - Program: Salyut. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,675 kg (14,715 lb). Perigee: 199 km (123 mi). Apogee: 276 km (171 mi). Inclination: 51.60 deg. Period: 89.30 min. Duration: 60.00 days.
  Unmanned Soyuz test flight. Recovered January 29, 1974 5:29 GMT. Soyuz 7K-T duration test.

• 1973 December 18 - Soyuz 13 - Program: Salyut. Crew: Klimuk, Lebedev. Flight: Soyuz 13. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,560 kg (14,460 lb). Perigee: 188 km (116 mi). Apogee: 247 km (153 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 7.87 days.
  A unique flight of the 7K-T/AF modification of the Soyuz spacecraft. The orbital module was dominated by the large Orion 2 astrophysical camera. The crew conducted astrophysical observations of stars in the ultraviolet range. Additional experiments included spectrozonal photography of specific areas of the earth's surface, and continued testing of space craft's on-board systems.

• 1974 October 1 - Soyuz 16A (cancelled) - Program: Salyut. Crew: Volynov, Zholobov. Flight: Soyuz 16A.
  Planned but cancelled third mission to the Salyut 3 space station.

• 1975 January 10 - Soyuz 17 - Program: Salyut. Crew: Grechko, Gubarev. Flight: Soyuz 17. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 185 km (114 mi). Apogee: 249 km (154 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 29.56 days.
  Manned two crew. Docked with Salyut 4. Joint experiments with the Salyut scientific orbital station.

• 1975 April 5 - Soyuz 18-1 - Program: Salyut. Crew: Lazarev, Makarov. Flight: Soyuz 18-1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. FAILURE: During second-third stage separation third stage failed to separate from second stage but still ignited. Mass: 6,830 kg (15,050 lb). Apogee: 192 km (119 mi). Duration: 0.0149 days.
  Carried Oleg Makarov, Vasili Lazarev for rendezvous with Salyut 4; but during second-third stage seperation third stage failed to separate from second stage but still ignited. The crew demanded that the abort procedures be implemented but ground control could not see the launch vehicle gyrations in their telemetry. Soyuz finally was separated from by ground control command at 192 km, and following a 20.6+ G reentry, the capsule landed in the Altai mountains, tumbled down a mountainside, and snagged in some bushes just short of a precipice. The crew was worried that they may have landed in China and would face internment, but after an hour sitting in the cold next to the capsule, they were discovered by locals speaking Russian. Total flight duration was 1574 km and flight time 21 minutes 27 seconds. Lazarev suffered internal injuries from the high-G reentry and tumble down the mountain side and never flew again. Both cosmonauts were denied their 3000 ruble spaceflight bonus pay and had to apeal all the way to Brezhnev before being paid.

• 1975 May 24 - Soyuz 18 - Program: Salyut. Crew: Klimuk, Sevastyanov. Flight: Soyuz 18. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,825 kg (15,046 lb). Perigee: 186 km (115 mi). Apogee: 230 km (140 mi). Inclination: 51.70 deg. Period: 88.60 min. Duration: 62.97 days.
  Manned two crew. Docked with Salyut 4. Joint experiments with the Salyut scientific orbital station. The crew remained aloft aboard the station during the Apollo-Soyuz Test Project joint flight.

• 1977 July 1 - Soyuz 25A (cancelled) - Program: Almaz. Crew: Berezovoi, Lisun. Flight: Soyuz 25A.
  A Soyuz 25 mission to the Salyut 5 space station with the crew of Berzovoi and Lisun was to have followed Soyuz 24. However during the four months it took to prepare the Soyuz, Salyut 5 consumed higher than expected fuel in maintaining the station's orientation. The flight was cancelled and the spacecraft allocated for Soyuz 25 flew as Soyuz 30 to Glushko's civilian Salyut station.

• 1977 October 9 - Soyuz 25 - Program: Salyut 6. Crew: Kovalyonok, Ryumin. Flight: Soyuz 25. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,860 kg (15,120 lb). Perigee: 194 km (120 mi). Apogee: 240 km (140 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 2.03 days.
  Manned two crew. Unsuccessful mission. Failed to dock with Salyut 6.

• 1977 November 1 - Soyuz 26A (cancelled) - Program: Salyut. Crew: Dzhanibekov, Kolodin. Flight: Soyuz 26A.
  Planned mission to Salyut 6 that would make first docking with rear docking port and be the first crew to swap spacecraft and return in the spacecraft that ferried the Soyuz 25 crew. But after Soyuz 25 failed to dock with Salyut 6 and Soyuz 26 as finally flown had quite a different crew and mission profile.

• 1977 December 10 - Soyuz 26 - Program: Salyut 6. Crew: Grechko, Romanenko. Flight: Salyut 6 EO-1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 205 km (127 mi). Apogee: 235 km (146 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 37.42 days.
  Manned two crew. Docked with Salyut 6. Carried Yuri Romanenko, Georgi Grechko to Salyut 6; returned crew of Soyuz 27 to Earth. Conduct of joint experiments with the Salyut-6 scientific station.

• 1978 January 10 - Soyuz 27 - Program: Salyut 6. Crew: Dzhanibekov, Makarov. Flight: Salyut 6 EP-1, Salyut 6 EO-1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 190 km (110 mi). Apogee: 237 km (147 mi). Inclination: 51.70 deg. Period: 88.70 min. Duration: 64.95 days.
  Manned two crew. Carried Oleg Makarov, Vladimir Dzhanibekov to Salyut 6; returned crew of Soyuz 26 to Earth. Docked with Salyut 6.

• 1978 March 2 - Soyuz 28 - Program: Salyut 6. Crew: Gubarev, Remek. Flight: Salyut 6 EP-2, Salyut 6 EO-1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 192 km (119 mi). Apogee: 246 km (152 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 7.93 days.
  Manned two crew. Docked with Salyut 6. Delivery to the Salyut-6 station of the first international 'Intercosmos' team consisting of A.A. Gubarev (USSR) and V. Remek (Czechoslovak Socialist Republic) to carry out scientific research and experiments jointly developed by Soviet a nd Czechoslovak specialists.

• 1978 June 15 - Soyuz 29 - Program: Salyut 6. Crew: Ivanchenkov, Kovalyonok. Flight: Salyut 6 EO-2. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 193 km (119 mi). Apogee: 248 km (154 mi). Inclination: 51.60 deg. Period: 88.90 min. Duration: 79.64 days.
  Manned two crew. Docked with Salyut 6. Placed on board the Salyut-6 station a crew consisting of V.V. Kovalenko and A.S. Ivanchenkov to conduct scientific and technological investigations and experiments.

• 1978 August 26 - Soyuz 31 - Program: Salyut 6. Crew: Bykovsky, Jaehn. Flight: Salyut 6 EP-4, Salyut 6 EO-2. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 193 km (119 mi). Apogee: 243 km (150 mi). Inclination: 51.60 deg. Period: 88.80 min. Duration: 67.84 days.
  Manned two crew. Docked with Salyut 6. Delivered to the Salyut-6 station the third international 'Intercosmos' crew consisting of V F Bykovsky (USSR) and S Jaehn (German Democratic Republic) to carry out scientific research and experiments.

• 1979 February 25 - Soyuz 32 - Program: Salyut 6. Crew: Lyakhov, Ryumin. Flight: Salyut 6 EO-3. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 193 km (119 mi). Apogee: 256 km (159 mi). Inclination: 51.60 deg. Period: 88.90 min. Duration: 110.18 days.
  Manned two crew. Docked with Salyut 6. Transported a team consisting of V A Lyakhov and V V Ryumin to the Salyut-6 space station to conduct scientific investigations and experiments and repair work. Recovered June 15, 1979 16:18 GMT. Returned unmanned.

• 1979 April 10 - Soyuz 33 - Program: Salyut 6. Crew: Ivanov Georgi, Rukavishnikov. Flight: Salyut 6 EP-5-1, Salyut 6 EO-3. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,860 kg (15,120 lb). Perigee: 194 km (120 mi). Apogee: 261 km (162 mi). Inclination: 51.60 deg. Period: 89.00 min. Duration: 1.96 days.
  Manned two crew. Flight under the Intercosmos programme of an international team consisting of N N Rukavishnikov (USSR) and G I Ivanov (Bulgaria). Unsuccessful mission. Failed to rendezvous with Salyut 6.

• 1979 June 6 - Soyuz 34 - Program: Salyut 6. Flight: Salyut 6 EO-3. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 192 km (119 mi). Apogee: 254 km (157 mi). Inclination: 51.60 deg. Period: 88.90 min. Duration: 73.76 days.
  Docked with Salyut 6. Launched unmanned to provide return vehicle for Soyuz 32 crew of Lyakhov/Ryumin after Soyuz 33 primary propulsion system failure. Checked the operation of the spacecraft propulsion unit; transportated the crew of the Salyut-6 station back to earth.

• 1980 April 9 - Soyuz 35 - Program: Salyut 6. Crew: Popov, Ryumin. Flight: Salyut 6 EO-4. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 197 km (122 mi). Apogee: 247 km (153 mi). Inclination: 51.60 deg. Period: 88.90 min. Duration: 55.06 days.
  Manned two crew. Docked with Salyut 6. Carried crew comprising L I Popov and V V Ryumin to the Salyut-6 station to carry out scientific and technical research and experiments.

• 1980 May 26 - Soyuz 36 - Program: Salyut 6. Crew: Farkas, Kubasov. Flight: Salyut 6 EP-5, Salyut 6 EO-4. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 190 km (110 mi). Apogee: 263 km (163 mi). Inclination: 51.60 deg. Period: 89.00 min. Duration: 65.87 days.
  Transported the fifth international crew under the INTERCOSMOS programme, comprising V N Kubasov (USSR) and B Farkas (Hungary) to the Salyut-6 station to carry out scientific research and experiments.

• 1980 July 23 - Soyuz 37 - Program: Salyut 6. Crew: Gorbatko, Tuan. Flight: Salyut 6 EP-7, Salyut 6 EO-4. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 190 km (110 mi). Apogee: 273 km (169 mi). Inclination: 51.50 deg. Period: 89.10 min. Duration: 79.64 days.
  Manned two crew. Transported to the Salyut-6 station the sixth international crew under the Intercosmos programme, comprising V V Gorbatko (USSR) and Pham Tuan (Viet Nam), to conduct scientific research and experiments. Returned crew of Soyuz 35 to Earth. Recovered October 11, 1980 9:50 GMT.

• 1980 September 18 - Soyuz 38 - Program: Salyut 6. Crew: Romanenko, Tamayo-Mendez. Flight: Salyut 6 EP-8, Salyut 6 EO-4. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 195 km (121 mi). Apogee: 257 km (159 mi). Inclination: 51.60 deg. Period: 89.00 min. Duration: 7.86 days.
  Manned two crew. Docked with Salyut 6. Transported to the Salyut-6 station the seventh international crew under the INTERCOSMOS programme, comprising Y V Romanenko (USSR) and A. Tomaio Mendez (Cuba), to conduct scientific research and experiments.

• 1981 March 22 - Soyuz 39 - Program: Salyut 6. Crew: Dzhanibekov, Gurragcha. Flight: Salyut 6 EP-9, Salyut 6 EO-6. Launch Site: Baikonur. Launch Complex: LC31. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 198 km (123 mi). Apogee: 249 km (154 mi). Inclination: 51.80 deg. Period: 88.90 min. Duration: 7.86 days.
  Manned two crew. Docked with Salyut 6. Transported to the Salyut-6 orbital station the eighth international crew under the INTERCOSMOS programme, comprising V A Dzhanibekov (USSR) and Z. Gurragchi (Mongolian People's Republic) to conduct scientific investigations and experiments.

• 1981 May 14 - Soyuz 40 - Program: Salyut 6. Crew: Popov, Prunariu. Flight: Salyut 6 EP-10, Salyut 6 EO-6. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 6,800 kg (14,900 lb). Perigee: 192 km (119 mi). Apogee: 270 km (160 mi). Inclination: 51.60 deg. Period: 89.10 min. Duration: 7.86 days.
  Manned two crew. Docked with Salyut 6. Transported to the Salyut-6 orbital station the ninth international crew under the INTERCOSMOS programme, comprising L I Popov (USSR), and D. Prunariu (Romania), to conduct scientific research and experiments.

• 1982 April 1 - Soyuz Almaz 4 (cancelled) - Program: Almaz. Crew: Malyshev, Laveykin. Flight: Soyuz Almaz 4.
  Planned Soyuz flight to a dock with the Almaz OPS 4 space station. The mission was cancelled together with the Almaz program in 1981.