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Soyuz-7 returns to Earth

After the final and unsuccessful attempt to dock the Soyuz-7 and Soyuz-8 spacecraft on October 16, 1969, ground control guided Soyuz-7 to landing the next day. With only a minor glitch in the flight control system to worry about, the three cosmonauts reentered the atmosphere on October 17, 1969.

Previous chapter: Soyuz-6 landing

Vladislav Volkov (left) and Anatoly Filipchenko inside descent module of the Soyuz-7 spacecraft.

Soyuz-7 and -8 make a new rendezvous attempt

Within hours after the landing of Soyuz-6 on October 16, 1969, mission control made two new attempts to guide Soyuz-8 and Soyuz-7 to a manual rendezvous. (820) The maneuvers started with orbit corrections during Orbit 81 of the joint mission. They were designed to bring Soyuz-7 and Soyuz-8 within 1.5 kilometers from each other with a relative speed of 0.3 meters per second, which would allow the ships to fly in formation for around 50 minutes.

However, notes from Mishin, (indirectly confirmed by Kamanin), indicate that while Soyuz-8 performed its maneuver as planned, the crew aboard Soyuz-7 made an error with the activation of its gyroscopic system, which would likely prevent the engine firing aboard Soyuz-7 after it would leave the communications range of Soviet ground stations.

As mission control was waiting for another communications session with the spacecraft during Orbit 82, specialists considered three scenarios of events which could take place during the communications blackout:

• Soyuz-7 and -8 conducted additional maneuvers during Orbit 82 to compensate for the problem during the Soyuz-7's correction.
• Soyuz-7 did not perform the orbit correction, but the two ships still ended up close enough for the crews to see each other and to begin the final approach.
• Soyuz-7 did not perform the orbit correction and the two crews had no visual contact.

If the latter supposition turned out to be correct, the controllers prepared commands for two more orbit corrections by Soyuz-8 during Orbit 84. The first would be performed at 16:40 with the DO propulsion system and the second maneuver would be performed at 17:47 Moscow Time with the SKDU propulsion system. Then, at the beginning of Orbit 85, on the daylight side of the planet, Soyuz-7 would perform one orbit correction to negate any lateral motion relative to Soyuz-8. (774)

However, despite all the preparations, the rendezvous and docking had failed again, primarily due to considerable errors during the planning of orbit corrections, Kamanin wrote. (820)

Mishin cited the following distance and relative speed between the ships at that time:

As Soyuz-7 was going out of range of ground control over the Atlantic on the evening of October 16, Kamanin congratulated Filipchenko and Gorbatko for earning the rank of "colonel" from the Air Force. (820)

Communications sessions between mission control and Soyuz-7, -8 on October 16, 1969, (Moscow Time):

(774)

October 17: Soyuz-7 lands

After exhausting all the opportunities for docking between Soyuz-7 and Soyuz-8, the two crews began preparations for landing.

The landing of Soyuz-7 was scheduled for the 97th orbit of the joint mission on October 17, 1969. The two final communications sessions between the crew of Soyuz-7 and ground control were scheduled at Orbit 95 from 9:12 to 9:22 Moscow Time and during the 96th orbit from 10:34 to 10:42 Moscow Time.

Two minutes after the start of the final communications window, the automated landing sequence was to be activated aboard Soyuz-7, at 10:46:10 Moscow Time on the command from the NIP-3 ground station in Sary Shagan. The braking engine firing was scheduled to begin at 11:44:11 Moscow Time (11:44:18 according to Mishin) to deliver a velocity change of 95 meters per second. The parachute system was to be activated at 12:12:34 Moscow Time on October 17, 1969, to ensure landing near Karaganda. (774)

Kamanin arrived at the mission control room in Yevpatoria at 8:00 and Pavel Popovich, who was acting as a communications officer with the crews during that shift, reported one potential problem aboard Soyuz-7. For an unknown reason, the light signaling the activation of the Automated Landing System, ASP, aboard the spacecraft had lit up on the flight control console inside the Descent Module. Normally, this signal would be on only after the separation of the modules or after pressing two buttons on the console. Obviously at the time, the spacecraft was still intact, and the cosmonauts had never commanded the automated landing sequence. Apparently, some electric malfunction had activated the signal and, therefore, there was some risk for triggering real unsanctioned commands. Kamanin called Filipchenko aboard Soyuz-7 and told him not to worry and wait for instructions from the ground.

Best experts in the main ground control station in Yevpatoria, Crimea, and in Moscow reviewed the situation and, after a long debate, everybody concluded that there was no way that the landing sequence could be activated before the separation of the modules. Ground controllers reported that news to the crew, but some concerns still lingered at mission control.

The SKDU propulsion system aboard Soyuz-7 initiated the braking maneuver at 11:44:13 Moscow Time and, at 11:56:17, the Descent Module separated from the rest of the spacecraft. Still, Filipchenko was able to maintain reliable communications with the ground after the modules' separation via a small antenna in the Descent Module. The capsule reached the parachute-opening altitude of seven kilometers at 12:12:30 Moscow Time and successfully touched down around 12:20 Moscow Time.

Two minutes after the landing, a search helicopter touched down near the capsule and a couple of minutes later, General Pushkin, responsible for search operations, reported to mission control that all three cosmonauts were in good shape. (820)

Communications sessions between Soyuz-7 and ground control on October 17, 1969:

Next chapter: Soyuz-8 landing

The article by Anatoly Zak; Last update: October 18, 2019

Page editor: Alain Chabot; Last edit: October 17, 2019

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Anatoly Filipchenko (left) and Vladislav Volkov inside descent module of the Soyuz-7 spacecraft.