5 September 1989 21:38 GMT. Landing Date: 1990-02-19 04:36:00 PM. Flight Time: 166.29 days. Alternate Name: Soyuz TM-8. Flight Up: Soyuz TM-8. Flight Back: Soyuz TM-8. Call Sign: Vityaz (Knight ). Crew: Serebrov, Viktorenko. Backup Crew: Balandin, Solovyov. Program: Mir. The Mir Expedition EO-5 docked with Mir on 8 September. The Mir orbital station team consisted of A S Viktorenko, commander of the spacecraft, and A A Serebrov, on-board engineer. The crew attached the new Kvant-2 module to the station and conducted five spacewalks in installation activities and test of the Soviet YMK manned maneuvering unit. Total mission cost was given as 80 million rubles, with an expected return of 25 million rubles net profit.
Narrative (adapted from D S F Portree's Mir Hardware Heritage, NASA RP-1357, 1995)
Soyuz TM-8 arrived at Mir after five months during which the station was uninhabited. The Kvant-2 and Kristall modules were now ready for launch, and the station began its second period of expansion. On September 29 the cosmonauts installed equipment in the docking system in preparation for the arrival of Kvant 2, the first of Mir’s 20-ton add-on modules. Solar storm warnings. On September 30 a powerful flare burst out on the Sun. Initial predictions indicated that the cosmonauts could receive many times the maximum permissible level of radiation. In the event, the cosmonauts received only about as much radiation as they would normally receive in two weeks of flight.
It was announced on October 10 that problems with a batch of computer chips pushed back the launch of Mir’s second add-on module by at least 40 days from the planned October 16 launch date. The major focus of Viktorenko and Serebrov’s mission was to receive, check out, and activate the module, so their schedule underwent heavy revision.
Kvant 2 was launched on November 26. Soon after launch the TsUP discovered that the right solar array had not deployed properly, allowing it to flop freely. By rolling Kvant 2 and rotating the array simultaneously, the TsUP was able to fully extend and lock the array. On December 2 Kvant 2 closed to within 20 m of the Mir front port before its Kurs control system terminated the approach. It had sensed that the module was moving too fast. Problems also developed on Mir: the Argon 16B control computer shut down the attitude control gyrodynes in Kvant after detecting an error. Viktorenko and Serebrov assumed manual control of Mir for the second attempt, which was successful. The Lyappa manipulator arm on Kvant 2 then inserted itself into a fixture on the multiport docking node and pivoted the module into place at the top lateral port. The transfer required about 1 hr
On 12 December the crew flew Soyuz TM-8 from the aft port of Mir and docked to the forward port now cleared of the Kvant-2 module. Progress-M 2 arrived at Mir and remained docked to the aft port from December 22, 1989-February 9, 1990
The new guidance control computer for Mir, the Salyut 5B system delivered by Kvant 2, needed star sensors more capable than those in place on Kvant. On January 8, in the first of the EVAs postponed from Principal Expedition 4, Viktorenko and Serebrov opened one of the three free docking node hatches, transferred the twin 80-kg sensor packages outside, and installed them on Kvant. Start of the 2-hr, 56-min EVA was delayed 1 hour by a depressurisation problem in Soyuz TM-8—when the cosmonauts lowered pressure in the docking node, an improperly set valve released air from the spacecraft as well.
On January 11 the cosmonauts became the last to use a docking node hatch for an EVA. They removed for return to Earth the Enchantillons space exposure experiment rack set up by Chretien during his December 1988 EVA, removed and discarded the ERA platform installed by Chretien and Volkov, and made modifications to the docking node in preparation for the arrival of the next large module, Kristall.
Cosmos 2054, the third Altair/SR geosynchronous satellite took up position at 344° E in mid-January. It was launched on December 27, 1989. Combined with Cosmos 1897, it permitted Mir to maintain contact with the TsUP in Moscow about 70% of the time.
On January 26 Viktorenko and Serebrov donned new Orlan-DMA spacesuits. These were improved versions of the Orlan suits they had worn on their first two EVAs. They then entered and depressurized the special EVA airlock compartment at the outboard end of Kvant 2. The EVA airlock hatch is wider than the docking hatches (1 m vs 0.8 m) to permit passage of the YMK, the Soviet MMU equivalent, which is stored in Kvant 2. The central instrument-science compartment of Kvant 2 can also be sealed and depressurised, expanding the size of the airlock and providing a backup. The cosmonauts attached a mooring post to the outside of the airlock compartment and removed a Kurs antenna so it could not interfere with future EVAs. EVA duration was 3 hr, 2 min.
The Soviet "flying armchair" manoeuvring unit weighed 218 kg and had been delivered to the station aboard Kvant-2. Serebrov donned the unit on February 1 and moved up to 33 m from the station. In case the YMK malfunctioned, during the test he was bound by a tether attached to a winch on the mooring post installed on the previous EVA. The EVA lasted 4 hr, 59 min.
On February 5 Viktorenko flew the YMK to a distance of 45 m. He carried the Spin-6000 device, which measured radiation from Mir induced by cosmic ray bombardment. EVA duration was 3 hr, 45 min.
On February 13 the EO-6 relief crew of Balandin and Solovyov arrived at the station aboard Soyuz TM-9. Soon after they arrived in orbit, Balandin and Solovyov noted that three of eight thermal insulation blankets on their spacecraft’s descent module had come loose at their lower (heat shield) ends and were waving about as the spacecraft manoeuvred in space. It was thought they could block optical navigation sensors, and that the damaged insulation might cause the spacecraft to overheat or cool down so much that condensation would form on its optical equipment. The possibility existed that an electrical short might occur if condensation developed on equipment. Docking with Mir occurred as normal. The cosmonauts and TsUP worked out procedures by which the TsUP monitored Soyuz TM-9's temperature and manoeuvred Mir to move it in and out of sunlight as needed to maintain proper temperature. In the meantime, cosmonauts worked in the hydrolab training facility in Zvezdny Gorodok, outside Moscow, to develop EVA repair procedures. Consideration was also given to sending a rescue Soyuz-TM carrying a single cosmonaut to pick up the cosmonauts and return them to Earth.
The problem was considered manageable and the Soyuz TM-8 crew had an uneventful return to earth after a productive mission.
Mir EO-5 Chronology
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