It’s getting dark, and Vladimir Dzhanibekov is cold. He has a flashlight, but no gloves. Gloves make it difficult to work, and he needs to work quickly. His hands are freezing, but it doesn’t matter. His crew’s water supplies are limited, and if they don’t fix the station in time to thaw out its water supply, they’ll have to abandon it and go home, but the station is too important to let that happen. Quickly, the sun sets. Working with the flashlight by himself is cumbersome, so Dzhanibekov returns to the ship that brought them to the station to warm up and wait for the station to complete its pass around the night side of the Earth. 
He’s trying to rescue Salyut 7, the latest in a series of troubled yet increasingly successful Soviet space stations. Its predecessor, Salyut 6, finally returned the title of longest manned space mission to the Soviets, breaking the 84-day record set by Americans on Skylab in 1974 by 10 days. A later mission extended that record to 185 days. After Salyut 7’s launch into orbit in April 1982, the first mission to the new station further extended that record to 211 days. The station was enjoying a relatively trouble-free start to life. 
However, this was not to last. On February 11, 1985, while Salyut 7 was in orbit on autopilot awaiting its next crew, mission control (TsUP) noticed something was off. Station telemetry reported that there had been a surge of current in the electrical system, which led to the tripping of overcurrent protection and the shutdown of the primary radio transmitter circuits. The backup radio transmitters had been automatically activated, and as such there was no immediate threat to the station. Mission controllers, very tired now that the end of their 24-hour shift was approaching, made a note to call specialists from the design bureaus for the radio and electrical systems. The specialists would analyze the situation, and produce a report and recommendation, but for now the station was fine, and the next shift was ready to come on duty.
Without waiting for the specialists to arrive, or perhaps not bothering to call them in the first place, the controllers on the next shift decided to reactivate the primary radio transmitter. Perhaps the overcurrent protection had been tripped accidentally, and if not, then it should still be functional and should still activate if there really was a problem. The controllers, acting against established tradition and procedures of their office, sent the command to reactivate the primary radio transmitter. Instantly, a cascade of electrical shorts swept through the station, and knocked out not only the radio transmitters, but also the receivers. At 1:20pm and 51 seconds on February 11, 1985, Salyut 7 fell silent and unresponsive. 
What do we do now?
The situation put flight controllers in an uncomfortable position. One option available to them was to simply abandon Salyut 7 and wait for its successor, Mir, to become available before continuing the manned space program. Mir was on schedule to be launched within one year, but waiting for Mir to become available would not only mean suspending the space program for a year; it also meant that a significant amount of scientific work and engineering tests planned for Salyut 7 would have to go undone. Moreover, admitting defeat would be an embarrassment for the Soviet space program, particularly painful considering the multitude of previous failures in the Salyut series as well as the apparent successes the Americans were enjoying with the Space Shuttle. 
There was only one other option: fly a repair crew to the station to fix it from the inside, manually. But this could easily become yet another failure. The standard procedures for docking to a space station were entirely automated and relied heavily on information from the station itself about its precise orbital and spatial coordinates. During those rare occurrences when the automated system failed and a manual approach was required, the failures were all within several hundred meters of the station. How does one approach a silent space station?  The lack of communication presented another problem: there was no way to know the status of the onboard systems. While the station was designed to fly autonomously, the automated systems could only cope with so many failures before human intervention would be required. The station could be fine upon the repair crew’s arrival, requiring no more repair work than replacing the damaged transmitters, or there could have been a fire on the station, or it could have depressurized from having been struck by space debris, etc.; there would be no way to know.
If there was a meeting in which top managers discussed and weighed all the options, the notes of that meeting have not been made public. What *is* known, however, is that the Soviets decided to attempt a repair mission. This would mean rewriting the book on docking procedures from scratch and hoping that nothing else went wrong aboard the station while communication was down, because if something else did go wrong, the repair crew might not be able to handle it. It was a bold move.
“Docking with a non-cooperative object”
The first order of business for the repair mission was figuring out how they would get to the station. For an approach to the station under better circumstances, the Soyuz (a 3-seat ship used to ferry cosmonauts to and from space stations) would receive information from the station via mission control (TsUP) as soon as it reached orbit, long before the station would be visible to the crew. This communication would contain information about the orbit of the space station so that the visiting craft could plot a rendezvous orbit. Once the two craft were 20-25km apart, a direct line of communication would be established between the station and the ship, and the automated system would bring the two craft together and complete the docking.
Although all Soyuz pilots were trained to perform a manual docking, it was rare for the automated system to fail. Of those rare failures, the worst was in June 1982 on Soyuz T-6 when a computer failure stopped the automated docking process 900m away from the station. Vladimir Dzhanibekov immediately took over controls and successfully docked his Soyuz with Salyut 7 a full 14 minutes ahead of schedule . Naturally, Dzhanibekov was the leading candidate to pilot any proposed mission to rescue Salyut 7.
An entirely new set of docking techniques had to be developed, and this was done under a project titled “docking with a non-cooperative object.”  The station’s orbit would be measured using ground-based radar, and this information would be communicated to the Soyuz, which would then plot a rendezvous course. The goal was to get the ship within 5km of the station, from which point it was deemed a manual docking was technically possible.  The conclusion of those responsible for developing these new techniques were that the odds of mission success were 70 to 80 percent, after proper modifications to the Soyuz. , The Soviet government accepted the risk, deeming the station too valuable to simply let it fall from orbit uncontrolled.
Modifications to the Soyuz began. The automated docking system would be removed entirely, and a laser rangefinder installed in the cockpit to assist the crew in determining their distance and approach rate. The crew would also bring night vision goggles in case they had to dock with the station on the night side. The third seat of the ship was removed, and extra supplies, like food and, as would later prove critical, water, were brought on board. The weight saved by the removal of the automatic system and the third chair were used to fill the propellant tanks to their maximum possible level. ,,
Who would fly the mission?
When it came to selecting a flight crew, two things were very important. First of all, the pilot should have had experience performing a manual docking in orbit, not just in simulators, and secondly, the flight engineer would need to be very familiar with Salyut 7’s systems. Only three cosmonauts had completed a manual docking in orbit. Leonid Kizim, Yuri Malyshev, and Vladimir Dzhanibekov. Kizim had only recently returned from a long duration mission to Salyut 7, and was still undergoing rehabilitation from his spaceflight, which ruled him out as a possible candidate. Malyshev had limited spaceflight experience, and had not trained for Extra-Vehicular Activity (EVA, or spacewalk), which would be required later in the mission to augment the station’s solar panels, provided the rehabilitation of the space station went well.
This left Dzhanibekov, who had flown in space four times for a week or two each time, but had trained for long duration missions and for EVA. However, he was restricted from long duration flight by the medical community. Being at the top of the short list for mission commander, Dzhanibekov was quickly placed into the care of physicians who, after several weeks of medical tests and evaluation, cleared him for a flight lasting no more than 100 days. 
To fulfill the role of flight engineer the list was even shorter: just one person. Victor Savinikh had flown once before, on a 74 day mission to Salyut 6. During that mission he played host to Dzhanibekov and Mongolia’s first cosmonaut as they visited the station on Soyuz 39. Moreover, he was already in the process of training for the next long-duration mission to Salyut 7, which had been scheduled to launch on May 15, 1985. 
By the middle of March, the crew had been firmly decided. Vladimir Dzhanibekov and Victor Savinikh were chosen to attempt one of the boldest, most complicated in-space repair efforts to date. 
Po’yehali! Let’s go!
As they approached the station, live video from their ship was being transmitted to ground controllers. To the right is one of the images controllers saw.
The controllers noticed something very wrong: the station’s solar arrays weren’t parallel. This indicated a serious failure in the system which orients the solar panels toward the sun, and immediately led to concerns about the entire electrical system of the station. 
The crew continued their approach.
Dzhanibekov: “Distance, 200 meters. Engaging engines. Approaching the station at 1.5 m/s, rotational speed of the station is normal, it’s practically stable. We’re holding, and beginning our turn. Oh, the sun is in a bad spot now… there, that’s better. Docking targets aligned. Offset between the ship and the station within normal parameters. Slowing down… waiting for contact.”
Silently, slowly, the crew’s Soyuz flew toward the forward docking port of the station.
Savinikh: “We have contact. We have mechanical capture.”
The successful docking to the station was a great victory, and demonstrated for the first time in history that it was possible to rendezvous and dock with virtually any object in space, but it was early to celebrate. The crew received no acknowledgement, either electrical or physical, from the station of their docking. One of the main fears about the mission, that something else would go seriously wrong while the station was out of contact, was quickly becoming a reality.
A lack of information on the crew’s screens about the pressure inside the station led to concerns that the station had de-pressurized, but the crew pressed ahead, carefully. Their first step would be to try to equalize the pressure between the ship and the station, if possible. 
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