Soyuz-11 begins a fateful expedition
to Salyut

On June 6, 1971, three Soviet cosmonauts, assigned to the flight at the last minute, departed Earth aboard the Soyuz-11 spacecraft for a record-breaking month-long flight aboard the Salyut space station.


Soyuz-11 crew during training inside the TDK-7K simulator in Star City.


Soyuz-11 mission at a glance:

Spacecraft designation
Soyuz, 7K-T No. 32, 11F615A8
Launch vehicle
11A511 (Soyuz)
Launch date and time
1971 June 6, 07:55:09 Moscow Time
Launch site
Landing date and time
1971 June 30, 02:16:52 Moscow Time*
2nd expedition to the DOS-1 (Salyut) space station
Primary crew
Georgy Dobrovolsky, Vladislav Volkov, Viktor Patsaev**
Backup crew
Aleksei Gubarev, Vitaly Sevastyanov, Anatoly Voronov**
Flight duration
23 days 18 hours 21 minutes 43 seconds

*Crew lost at landing; **As of June 3, 1971

Fateful crew replacement

The crew which ended up aboard the Soyuz-11 spacecraft was originally expected to be the third in line to visit the Salyut space station, DOS-7K. In mid-February 1971, the crews training for the expeditions to the first Salyut had the following composition:

  • Vladimir Shatalov, Aleksei Yeliseev, Nikolai Rukavishnikov;
  • Aleksei Leonov, Valery Kubasov, Petr Kolodin;
  • Georgy Dobrovolsky, Vladislav Volkov, Viktor Patsaev;
  • Aleksei Gubarev, Vitaly Sevastyanov, Anatoly Voronov.

These crews started final training in early March 1971. Following the botched attempt to deliver the first crew to the station aboard the Soyuz-10 spacecraft (7K-T No. 31) at the end of April 1971, the three remaining crews resumed training in May 1971.

Soon after the Soyuz-10 returned to Earth on April 25, Designer General at the TsKBEM bureau Vasily Mishin apparently considered removing one member from the Soyuz-11 crew, so that it would be possible to configure the spacecraft for spacewalking capabilities. According to his plan, one of the crew members would walk outside to ensure the absence of damage on the docking port of the station and on its instrument compartment cover, which failed to separate after the Salyut had entered orbit. No doubt, both tasks posed a significant risk and technical obstacles. Mishin still discussed the idea was Kamanin on April 30, 1971, but the plan was dropped by May 3, primarily due to lack of time for training the crew, which required between two and three months, especially under a deadline imposed by the remaining resources aboard the Salyut providing operations for 60 or 70 days. Some consideration would be given to a spacewalk during the second expedition to Salyut, then expected in early June.

During a Chief Designers' meeting on May 7, 1971, Boris Chertok, Deputy to the Head of TsKBEM, reported on the results of the analysis into the failure of the docking mechanism during the Soyuz-10 flight. With all the lessons learned, Chertok confirmed that the docking port on the crew vehicle No. 31 was ready for the new docking attempt, even though validation tests were scheduled to continue until May 18. During the same event, another of Mishin's deputy Konstantin Bushuev reported on the resolution of other open issues with the orbiting Salyut, including failed interior fans and the related operation of the life-support system. He also apparently touched upon the operation of the DPO thrusters whose unexpected firing during docking of Soyuz-10 overstressed its docking mechanism. (774) By that time, the Soyuz-11 expedition to the station was planned for June 1971, followed by Soyuz-12 launching between the 15th and 18th of July.

On May 25, 1971, the meeting of the State Commission overseeing the readiness of the fresh expedition to Salyut, cleared the Soyuz 7K-T No. 32 crew vehicle for irreversible operations and set its launch to the station for June 6, 1971. On the evening of June 3, 1971, when all the Salyut cosmonauts were at the launch site in Tyuratam, and the fully assembled rocket was ready for the rollout to the pad the next morning, medical officials announced that the latest X-ray images had revealed an egg-sized dark spot in the right lung of Valery Kubasov, possibly indicating an early stage of tuberculosis. To the shock of many engineers, Kubasov had had a previous X-ray exam in February, when there was no signs of problems, while in previous flights, cosmonauts were cleared for flights without any X-rays.

It meant that three days before the scheduled launch, Kubasov was disqualified from the flight. What's worse, the loss of a single crew member such a short time before flight required to replace the entire crew with its backup, according to existing regulations. Despite that, the usual quarrel broke out between Mishin and the head of cosmonaut training Nikolai Kamanin, who, citing the complexity of the upcoming mission, insisted on replacing Kubasov with Vladislav Volkov, leaving Leonov and Kolodin onboard. (231)

Because the spacecraft was already under the payload fairing, processing specialists faced a considerable challenge replacing custom-built seat liners, medical sensors and other personalized equipment inside the vehicle. The ship's center of mass was also had to be recalculated because of differences in weight between different crew members.

Nevertheless, during a late-night meeting of engineers at the end of the day on June 3, they estimated the time required for the equipment swap on the pad at just four or five hours.

According to recollections of journalist Yaroslav Golovanov, in the ensuing mayhem, Leonov had successfully lobbied generals on the State Commission to replace Kubasov with Volkov, but, suddenly, Volkov demanded that officials stick with the rules, probably out of solidarity with his teammates.

On the morning of June 4, when the rocket with the spacecraft had already rolled out to the pad, the State Commission met again to settle the issue of crew assignment. There was another heated debate, where Kamanin argued for the replacement of just Kubasov with Volkov, while Mishin demanded the entire crew be swapped, citing the mutual understanding developed between crew members in the course of joint training. Surprisingly, the Deputy Air Force commander supported Mishin's position. However, Chertok's colleague Yevgeny Bashkin privately noted that his flight control team spent most of their training effort on the primary crew, since they simply did not have enough time to dedicate an equal attention to the backup crew. (78)

In any case, the majority voted for the replacement of all three cosmonauts. On the same day, military doctors, who had been urgently flown to the launch site, re-confirmed their bad diagnosis for Kubasov. So, on the evening of June 4, some 48 hours before the launch, the ceremonial meeting of the State Commission had formally approved Dobrovolsky, Volkov and Patsaev for the flight. Kubasov never developed any lung problems and would later be cleared for space missions.

Fight over the flight program

The flight duration of the first expedition aboard Salyut had also been the subject of a prolonged debate in early 1971. Vasily Mishin, the head of the TsKBEM design bureau, insisted on a month-long residence, while head of the cosmonaut training center, TsPK, Nikolai Kamanin argued for a shorter flight, remembering the poor condition of the Soyuz-9 crew after its 18-day record-breaking flight a few months earlier. In his argument, Kamanin relied on the decisions of a medical conference at TsPK in the aftermath of the Soyuz-9 mission. At the event, specialists warned against sharp increases of flight duration from 18 to 30 and 60 days planned for Salyut and, instead recommended the first expedition to last from 20 to 24 days. Kamanin argued that the Soyuz-9 crew was lucky "to land in the hands of the doctors," however if the next mission would end up in a hard-to-reach location, even a few-hour delay with the arrival of search teams could pose a serious health risk or even lead to the death of the crew weakened by the long exposure to weightlessness. Kamanin believed that the 30-day mission duration posed an acceptable risk while all the scientific and political objectives of such and expedition could be achieved in a shorter flight.

The debate over the mission duration apparently reached all the way to the Kremlin. Kamanin remembered that Mishin was lobbying for a 30-day flight with influential government officials Dmitry Ustinov and Leonid Smirnov and even the Soviet leader Leonid Brezhnev. Mishin also solicited support from top officials at the health ministry, as well as from the Central Committee of the Communist Party and the Soviet of Ministers.

On February 24, Leonid Smirnov, Deputy Chairman at the Soviet of Ministers, called the newly appointed Air Force commander, Marshal Kutakhov and asked him to rein in Kamanin on the issue of flight duration. Kamanin remembered that during his phone call with his the Air Force commander next day, Kutakhov's argument boiled down to "it was not a good idea to have that a conference (questioning the flight duration), because the bosses know better how and for how long to fly in space." (774)

Kamanin was clearly outgunned and during the Chief Designers' meeting on March 3, 1971, Mishin confirmed that the first crew would fly for 30 days and the second expedition would last 45 days. At the time, the station and a pair of Soyuz spacecraft had passed the factory tests and were ready for shipment to the Tyuratam launch site.

Because the first crew sent to Salyut in April 1971 was not able to get onboard the station and had to return to Earth after a two-day flight, the task of long-duration expedition fell on the following crew.

By May 14, Mishin agreed to a compromised flight duration of 25 days, with the launch on June 6, 1971.

Soyuz-11 lifts off

The second expedition to Salyut-1, lifted off from Tyuratam on June 6, 1971, at 07:55:09 Moscow Time. Soyuz-11 successfully entered orbit at 08:04 Moscow Time. At 13:50 Moscow Time, Soyuz-11, under manual attitude control, conducted an orbit correction maneuver to intercept the station early in the second day in orbit. Between 15:40 on June 6 and 01:30 Moscow Time on June 7, the spacecraft was out of range of the Soviet ground stations and the crew spent much of that time sleeping.

On June 7, at the start of the communications window from 07:25 to 07:48, the crew of Soyuz-11 reported that the Igla system had successfully homed in on the Salyut and begun an automated rendezvous process. At 07:31, the SKD main engine aboard Soyuz automatically fired for 10 seconds further closing the distance with its destination. By 07:37, the crew ship was reported to be within 700 meters of Salyut. At the communications console at the NIP-16 ground station, Aleksei Yeliseev advised the crew to take a close look at the docking mechanism on the station's side before committing to the final approach.

Shortly before the spacecraft went out of range, the NIP-13 ground station near Ulan-Ude, east of Lake Baikal, reported that the berthing process had started and that Soyuz-11 was 300 meters from Salyut. The crew also confirmed that the ship had aligned its roll axis with the station's and that the cosmonauts had switched to a manual berthing as planned.

The physical contact and docking took place at 07:49:15 Moscow Time, outside the view of ground stations. The docking process was completed at 07:55:30 Moscow Time. After the docked vehicles reentered the ground station range during the 19th orbit of the Soyuz-11 mission, the cosmonauts radioed that they had a perfect view of the cone receptacle on the station's docking mechanism and it looked absolutely clean.

Salyut opens for business

After four hours of careful leak checks, the command to open the hatch between Soyuz-11 and Salyut-1 was issued at 10:32:30 Moscow Time on June 7, 1971. The crew moved inside the world’s first true space laboratory at 10:45 Moscow Time.

Inside the airy outpost everything seemed normal except for a strong burning smell. Patsaev, who ventured into the station for the initial survey, turned on lights and confirmed that two out of eight air fans had failed. Their burned wires probably left some smoke in the atmosphere. Patsaev activated the air-conditioning system, but the crew remained in their Soyuz for the first night. Two of the cosmonauts slept in the Habitation Module and one in the Descent Module across three passenger seats. By the next day, the air onboard returned to normal and the crew could mothball their transport ship before moving into the station. The cosmonauts also succeeded in raising the station’s orbit with its engines and putting it into a slow spin so that the sun heated the station’s surfaces evenly.

Impressed with their new voluminous residence in space, the cosmonauts performed somersaults in front of a TV camera to the delight of flight controllers. The footage even made it beyond the high walls of the secretive space organizations and onto the TV screens of Soviet citizens.

In the meantime, the cosmonauts set out to a hectic program of onboard experiments with a strong emphasis on studying effects of weightlessness on the human body. They had to go through an unpleasant process of collecting frequent blood samples, taking seismocardiograms, measuring the flow of blood and arterial pressure, checking the capacity of the respiratory system and the electrical activity of the heart.

In between, the cosmonauts also had to constantly monitor and maintain the health of the station, take care of a miniature plant collection and conduct other experiments, not to mention, exercise intensively. A special vacuum suit, known as Pingvin (penguin), was used to redistribute the flow of blood back toward the lower part of the body, thus counteracting the effect of weightlessness. The crew members even attempted to sleep in the bulky costume. Tired of their camper hygiene, Dobrovolsky and Volkov gave up shaving and grew considerable beards, while Patsaev stubbornly tried to maintain a civilized look.

The cosmonauts apparently faced the increasing pressure of the long flight, as mission controllers witnessed tension and misunderstanding onboard. On the ground, fellow cosmonauts Nikolaev, Yeliseev, Shatalov, Bykovsky and Gorbatko, who were taking turns at the flight manager console at the Crimean ground station, had to play the role of mediators to reconcile frequent disagreements in orbit.

"Fire" onboard Salyut


Aleksei Yeliseev (top) at the mission control console communicating with Salyut.

On June 16, during Shatalov’s shift as a flight manager, he received an urgent call from Volkov, reporting "zavesa" onboard, which can be translated as "riddle," "veil" or "pall." When ground controllers, who forgot the exact meaning of code words, asked for clarification, Volkov apparently barked "we have a f-ing fire onboard, now leaving for the crew vehicle." He also anxiously said that they could not find documents for urgent evacuation and demanded instructions be read over the radio. In the following tense exchange with Volkov, bordering panic, mission control understood that the smoke was coming from the Control Console of the Science Equipment, PUNA.

After a period of confusion, mission control started reading to the crew the necessary steps for evacuation procedures but warned them not to be in a hurry because the PUMA console was deactivated and the telemetry was showing good parameters on oxygen and CO2 contents in the atmosphere. The ground controllers assured the crew that the smoke should quickly dissipate.

Dobrovolsky then joined the communications and confirmed that the crew had switched to a backup power supply circuit and activated air filters. He assured mission control that the crew would remain onboard.

With great relief, mission control called off the evacuation of the station after several hours of uncertainly. All unessential equipment onboard remained powered down for the time being. According to Kamanin, in the wake of the incident, mission control was not particularly happy with Volkov’s performance, who came across as overly anxious and bossy. (774) Chertok echoed Kamanin's opinion, saying that ground controllers understood that Dobrovolsky and Patsaev had to calm Volkov down.

In the following days, under careful watch from the ground, the crew started turning on the station’s equipment one by one. From June 18, the Orion telescope was employed for the cartography of the night sky in the ultraviolet range of spectrum, which is largely filtered by the Earth atmosphere. Despite the official “civilian” status of Salyut, the crew conducted experiments aiming at detecting night launches of ballistic missiles.

The cosmonauts conducted experiments with the OD-4 military range finder and the top-secret Svinets (lead) radar. Specifically for those experiments, a pair of TR-1 rockets were launched from Tyuratam on June 24 and June 25, 1971.

Various medical and engineering studies were also completed. (78)

Preparing for landing

On June 24, the Soyuz-11 crew broke the flight-duration record, which had been set in the previous year by the Soyuz-9 crew.

However, the cost of this achievement continued mounting. While, more than a week still remained in the 25-day flight program, the cosmonauts sounded exhausted to Kamanin. Doctors also warned that the crew had not being doing enough exercise to counteract the dangerous effects of weightlessness. In their defense, the cosmonauts complained that the poorly designed exercise machine was breaking down, causing a lot of noise and shaking the entire station, so that they could feel the vibration of solar panels and the sloshing of propellant in the tanks. To make it worse, all of that was taking place when the two other crew members would often try to sleep! Remembering the traumatic experience of Soyuz-9 cosmonauts, mission officials finally made the decision to prepare the crew for a return home early, after a 23-day flight.

By June 26, all scientific experiments onboard the station were wrapped up and the crew of Soyuz-11 started the laborious task of mothballing the station in preparation for their return. Since a fresh expedition was expected to re-visit Salyut-1 in two or three weeks, the Soyuz-11 crew members paid particular attention to leaving the outpost in a safe and operational condition. (231)

In one of the last activities aboard Salyut, the cosmonauts used their unique vantage point to watch the long-delayed and ultimately failed third launch of the giant N1 Moon rocket in the early hours of June 27, 1971, which almost overshadowed the Salyut mission in the minds of numerous TsKBEM specialists who worked on both projects. But they had to turn back to Salyut in a bad and tragic way very soon...

Soyuz-11 crew lost at landing

On June 30, 1971, the three members of the Soyuz-11 crew lost their lives just minutes from landing when their Descent Module suddenly depressurized on its way back to Earth from the Salyut orbital laboratory.


Next chapter: Loss of Soyuz-11 crew


The article by Anatoly Zak; Last update: March 22, 2024

Page editor: Alain Chabot; Last edit: June 6, 2021

All rights reserved


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The original primary crew of the Soyuz-11 mission (left to right) Petr Kolodin, Valery Kubasov and Aleksei Leonov. Nikolai Rukavishnikov from the Soyuz-10 crew is on the right. Click to enlarge. Credit: Roskosmos


Primary and backup crews from the Salyut project probably during one of the meetings of the State Commission. Click to enlarge. Credit: Roskosmos


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Soyuz-11 crew during training. Click to enlarge. Credit: Roskosmos


Soyuz-11 crew in Tyuratam. Click to enlarge. Credit: Roskosmos


Soyuz-11 crew inside the Descent Module.



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Rollout of the launch vehicle with the Soyuz-11 spacecraft. Click to enlarge.


The State Commission approves the Soyuz-11 crew for launch.


Soyuz-11 crew arrives at the launch pad on June 6, 1971. Click to enlarge


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Commander of the Soyuz-11 crew reports about the readiness for flight on the launch pad shortly before boarding the spacecraft on the launch day.


Members of Soyuz-11 crew bid farewell to well wishers before boarding the spacecraft. Click to enlarge.


Soyuz-11 lifts off from Tyuratam on June 6, 1971. Click to enlarge.


Cosmonauts entered the first Salyut on June 7, 1971. Click to enlarge.


Cosmonauts inside Salyut. Click to enlarge.


Cosmonauts inside Salyut. Click to enlarge.








Members of Soyuz-11 crew work aboard Salyut. Click to enlarge.