The little-known Soviet mission to rescue a dead space station (3)
The indicator tubes indicated the atmosphere on the station was normal, so the crew equalized the pressure between the compartments in a similar manner to what they had done before with the outside hatch of the airlock. Mission control advised them to put on their gas masks, just in case, and open the hatch.
They floated in with their flashlights and their winter coats, and found the station cold and dark, with frost along the walls. Savinikh tried to turn the lights on—nothing, not that he expected anything. They took off their gas masks—they were making it even more difficult to see around the darkened station, and there was no smell of fire. Savinikh dived to the floor and opened the shade covering a window. A ray of sunlight fell on the ceiling, illuminating the station a little bit. They found the crackers and salt tablets that were left on the table by the previous crew—part of a traditional Russian welcoming ceremony that is still performed on the ISS today—as well as all the onboard station documentation neatly packed and secured to its shelves. All of the ventilators and other systems that normally hummed noisily were off. Savinikh recalls in his flight journal “it felt like being in an old, abandoned home. There was a deafening silence pressing upon our ears.” [1]
Now that the crew and mission control were aware of their predicament, they had to do something about it. The crew woke the next morning to instructions from the ground: first examine “Rodnik,” the potable water storage system, and see if the water there was frozen. They were also given limitations on their ability to work. Due to the lack of ventilation in the frozen station, a cosmonaut’s exhalations would build up around him, and he could easily succumb to carbon dioxide poisoning. Therefore the ground limited the crew to working in the station one at a time, with the one in the ship keeping an eye on the one in the station for signs of CO2 poisoning. Dzhanibekov went first.
Earth: “Volodya, if you spit, will it freeze?”
Dzhanibekov: “I’m trying it now. I spit, and it froze. In three seconds.”
Earth: “Did you spit right on the window, or where?”
Dzhanibekov: “No, on the insulation. The rubber here is frozen. It’s like a rock.”
Earth: “That doesn’t make us feel any better.”
Dzhanibekov: “Us neither.”
Later, Savinikh took his place, and tried to pump air either in or out of the air bladders of the system.
Savinikh: “I’ve gotten the Rodnik schematics. Pump connected. The valves aren’t opening. There’s an icicle sticking out of the air pipe.”
Earth: “Understood, let’s put Rodnik aside for now. We’ll run to the other side. We need to know, how many “live” battery blocks there are that we can reanimate. We’re working on a procedure to connect the station’s solar panels directly to the blocks.”
The problem with Rodnik was serious. The crew had water reserves for eight days in total, enough to last until June 14. It was already flight day 3—if they rationed their water use down to a minimum, tapped into the Soyuz’s emergency water supply, and managed to heat up a couple water packets that were on the station, they could stretch their supplies until June 21, giving themselves not more than 12 days to repair the station. [1]
Dzhanibekov works in the cold to repair Salyut 7The station’s batteries were normally charged by an automated system, which itself needed electricity in order to function. Somehow, the crew needed to get electricity into the batteries. The easiest way to recharge them would have been to transfer power from the Soyuz’s batteries, but it was still unclear what the status of the station’s electrical system was. If there was still an electrical short somewhere in the station’s systems, it could knock out the Soyuz’s electrical system as well, and the cosmonauts would be stranded. [1]
Instead, ground controllers came up with a complex procedure for the crew to implement. Firstly, they would test the station’s batteries to see how many of them could accept a charge. Much to their happiness, six of the eight batteries were deemed salvageable. Next, the crew prepared cables to connect the batteries directly to the solar panels. All told, they had to put together 16 cables, connecting the leads of the cables by their bare hands in the cold of the station. With the cables connected, the crew would clamber into the Soyuz and use its attitude control engines to re-orient the station so that its solar panels would face sunlight.
Earth: “We’re going to go a turn around the Y-axis using the control system of Soyuz T-13 to light up the solar panels. Before our next communications session, we need you to connect the positive leads to all the good battery blocks. Then we’ll complete the re-orientation and start charging the first block."
Dzhanibekov: “We’re going to do this manually?”
Earth: “Yes, manually.”
Savinikh: “OK.”
Dzhanibekov: “I’m ready.”
Earth: “Turn along the pitch axis until the sun comes into view. As soon as that happens, start braking the rotation.”
Dzhanibekov: “OK. Handle is down. Pitching.”
Earth: “Have you started braking yet?”
Dzhanibekov: “Not yet.”
Earth: “The air also concerns us. We need to organize a duct in the work section.”
Dzhanibekov: “Understood. We only have one regenerator [CO2 scrubber]: that’s why the readings take so long to get to the desired level."
Earth: “We’ll think about it: maybe install a second regenerator.”
Dzhanibekov: “We have enough cables for that…. the sun is centered in my visual field...turning clockwise.”
Savinikh: “It’s like in good winter weather. There’s snow on the windows and the sun is shining!”
Earth: “We consider the charging to have begun.”
Dzhanibekov: “Thank God!”
Earth: “Not understood. We didn’t hear you.”
Dzhanibekov and Savinikh together: “Thank God!”
Earth: “Great work.”
Savinikh notes in his flight journal, “that day was the first happy spark of hope in that mountain of problems, unknowns, and hardships that Volodya and I were faced with solving”
All the while they had been working, they really didn’t know if they would be staying, or if they would run out of water first. They tried not to talk about it, focusing instead on their work. After having re-orientated the station and waiting for about a day, five batteries had been charged.
The crew disconnected them from their rudimentary charging system, and connected them to the station’s electrical grid. They turned on the lights, and much to their relief, the lights came on.
Over the next few days, they set about re-initializing various systems on board the station. They turned on the ventilation and air regenerators so that they could both work on the station at the same time. There was so much to do, that they spent the entire day in the station, coming back to the Soyuz to sleep happy and “wonderfully frozen.” [1]
On June 12, flight day 6, the crew began replacing the fried communications system and testing the water coming out of the slowly-thawing Rodnik system for contaminants.
On June 13, flight day 7, the crew continued their work with the communications system, and by afternoon Moscow time, ground control had re-established a link with the station. They also tested the automatic docking system, knowing that if the test failed they would have to go home. The station needed supplies, and they could only be brought in large enough quantities by cargo ships which could not be controlled manually like the Soyuz. But thankfully, the test was successful, and the cosmonauts continued their mission.
Finally, on June 16—flight day 10 and two days after water supplies were initially supposed to run out—“Rodnik” was fully operational. There were finally enough working systems and enough supplies to continue the mission. [1]
Dzhanibekov and Savinikh report from a recently-revived Salyut 7.The rest of the storyA single faulty sensor was determined to be the cause of the station’s descent into a frozen darkness. It was a sensor which monitored the state of charge of battery number four. The sensor was designed to shut down the charging system when the battery to which it was connected was full, in order to prevent overcharging that battery. Each of the seven primary batteries and the single backup battery had such a sensor and any one of the sensors - primary or backup - had the authority to shut down the charging system. [3]
At some point after the loss of communication with the station, battery four’s sensor developed a problem. It began to report the battery as full even when it wasn’t. Every time the on-board computer sent a command to charge the batteries, which happened once a day, battery four’s sensor would immediately cancel the charge. Eventually on-board systems drained the batteries completely, and the station slowly began to freeze. Had communication with the station been available, controllers could have intervened and overridden the faulty sensor. Without communication, it was impossible to tell exactly when the sensor had failed. [3],[12]
Dzhanibekov stayed on the station for a total of 110 days. He returned home on Soyuz T-13 with Georgi Grechko, who had flown up to the station with Vladimir Vasyutin and Alexander Volkov on Soyuz T-14 in September of 1985. Vasyutin, Volvkov, and Savinikh remained on board for a long term expedition which was cut short in November as Vasyutin fell ill, forcing an emergency return to Earth.
On February 19, 1986, the core block of Salyut 7’s successor station, Mir, was launched. Although its replacement was in orbit, Salyut 7’s role in the Soviet space station program was not quite finished. The first crew to launch to Mir did something unprecedented. After arriving at Mir and performing initial operations to bring the new station online, they boarded their Soyuz and flew to Salyut 7, the first and, to date, only time in history a station-to-station crew transfer had taken place. They completed the work left behind by the Soyuz T-14 crew, after which they returned to Mir before eventually returning to Earth.
The Soviets hoped to continue using Salyut 7 even after Soyuz T-15 had departed, and so the station was placed into a high altitude storage orbit. However, with the collapse of the Soviet Union and the Russian economy, funding for future missions to Salyut 7, either with Soyuz ships or the then-in-development Buran shuttle, never materialized, and the station’s orbit slowly degraded until it underwent an uncontrolled re-entry over South America in 1991. [7]
Although the station itself is gone, its legacy of triumph over adversity remains. Salyut 7 experienced some of the most serious problems of any station in the Salyut series, but while earlier stations were lost, the skill and determination of the designers, engineers, ground controllers, and cosmonauts of Salyut 7 kept the station flying. That spirit lives on today in the International Space Station, which has flown continuously for over 15 years. It too experiences systems failures, coolant leaks, other problems, but like their predecessors who worked on Salyut 7, the designers, engineers, ground controllers, cosmonauts, and astronauts exhibit that same determination to keep flying.
Nickolai Belakovski is an engineer with a background in aerospace engineering. He is fluent in English and Russian and gathered a number of technical and non-technical sources in order to understand what really happened in the leadup to and execution of the Soyuz T-13 mission. His bibliography is included below.
1. Savinikh, Victor. "Notes from a Dead Station." Publishing House of the Alice System. 1999. Web. <http://militera.lib.ru/explo/savinyh_vp/index.html> *
2. Gudilin, V. E., Slabkiy, L. I. “Rocket-space systems.” Moscow, 1996. Web. <http://www.buran.ru/htm/gudilin2.htm> *
3. Blagov, Victor. "Technical abilities, mastery, and the courage of people." Science and Life, 1985, volume 11: pages 33-40. Web. <http://epizodsspace.no-ip.org/bibl/n_i_j/1985/11/letopis.html> *
4. Portree, David S. F. Mir hardware heritage. Washington, DC: National Aeronautics and Space Administration, 1995. Print. Web. <http://ston.jsc.nasa.gov/collections/TRS/_techrep/RP1357.pdf>
5. Glazkov, Yu. N., Evich, A. F. “Repair on Orbit.” Science in the USSR, 1986, volume 4. Web. <http://epizodsspace.no-ip.org/bibl/nauka-v-ussr/1986/remont.html> *
6. "Soyuz T-13." Wikipedia. Wikimedia Foundation, 21 Apr. 2014. Web. <http://en.wikipedia.org/wiki/Soyuz_T-13>.
7. Mcquiston, John. "Salyut 7, Soviet Station in Space, Falls to Earth After 9-Year Orbit." The New York Times. The New York Times, 6 Feb. 1991. Web. <http://www.nytimes.com/1991/02/07/world/salyut-7-soviet-station-in-space-falls-to-earth-after-9-year-orbit.html>
8. Kostin, Anatoly. "The Ergonomic Story of the Rescue of Salyut 7." Ergonomist, February 2013, volume 27: pages 18-22. Web. 26 May 2014. <http://www.ergo-org.ru/newsletters.html> *
9. Chertok, B. E. "People in the Control Loop." Rockets and People. Washington, DC: NASA, 2011. 513-19. Web. 09 Aug 2014. <http://www.nasa.gov/connect/ebooks/rockets_people_vol4_detail.html> [English], <http://militera.lib.ru/explo/chertok_be/index.html> [Russian]
10. Nesterova, V., O. Leonova, and O. Borisenko. "In Contact -- Earth." Around the World, October 197, volume 2565: issue 10 Web. 9 Aug. 2014. <http://www.vokrugsveta.ru/vs/article/3714/>.*
11. Canby, Thomas Y. "Are the Soviets Ahead in Space?" National Geographic 170.4 (1986): 420-59. Print.
12. Savinikh, Victor. "Vyatka Baikonur Space." Moscow: MIIGAAiK. 2002. Web. <http://epizodsspace.airbase.ru/bibl/savinyh/v-b-k/obl.html>>*
Source: * denotes a source in Russian
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