Crew

Launched:

• Anatoly Solovyev (1)
• Viktor Savinykh (1)
• Aleksandr Panayatov Aleksandrov (1) - Bulgaria

Landed:

• Vladimir Lyakhov (3)
• Abdul Ahad Mohmand (1) - Afghanistan

Mission Parameters

• Mass: 7000 kg
• Perigee: 173 km
• Apogee: 241 km
• Inclination: 51.6°
• Period: 88.6 minutes

Mission Highlights

5th expedition to Mir.

Arrived at Mir carrying the second Bulgarian in space, Alexandrov (not to be confused with the Soviet cosmonaut of the same name). He became the first Bulgarian to reach a Soviet space station (Georgi Ivanov failed to reach Salyut 6 on Soyuz 33 in 1979—Alexandrov was his backup). Their launch had been advanced by 2 weeks late in the planning stages to improve lighting conditions for the Rozhen astronomical experiment. On September 5 cosmonauts Alexandr Lyakhov and Abdul Ahad Mohmand undocked from Mir. They jettisoned the orbital module and made ready for deorbit burn to return to Earth. However, unbeknownst to the cosmonauts or TsUP, the guidance computer was using the docking software of the Bulgarian Mir mission in June. The deorbit burn did not occur at the appointed time because the infrared horizon sensor could not confirm proper attitude. Seven minutes after the scheduled time, the sensor determined that the correct attitude had been achieved. The main engine fired, but Lyakhov shut it down after 3 s. A second firing 3 h later lasted only 6 s. Lyakhov immediately attempted to manually deorbit the craft, but the computer shut down the engine after 60 s. The cosmonauts were forced to remain in orbit a further day. Even if the main engine had permitted them to do so, they would not have been able to redock with Mir because they had discarded the docking system along with the orbital module. The cosmonauts were left for a day in the cramped quarters of the descent module with minimal food and water and no sanitary facilities. Reentry occurred as normal on September 7. After this the Soviets retained the orbital module until after deorbit burn, as they had done on the Soyuz Ferry flights.