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Soyuz-3: Just a small mistake

Anatoly Zak, Spaceflight Correspondent
Nov 2, 2015, 19:42 UTC

Sen—After the tragic death of Vladimir Komarov at the end of the Soyuz-1 mission in April 1967, Soviet engineers went back to the drawing board to re-design the ill-fated parachute system for the new spacecraft. Extensive tests were ordered both on the ground and in space.

In October 1967, two Soyuz spacecraft without cosmonauts onboard lifted off within three days from each other under cover-up names Kosmos-186 and Kosmos-188. They made the world's first fully automated rendezvous and docking in space. However the mission again revealed multiple technical problems and only one of the two descent modules made it back to Earth. In April 1968, another pair of unmanned Soyuz spacecraft repeated the docking mission under the names Kosmos-212 and Kosmos-213.

Finally, in August 1968, another unmanned Soyuz flew a solo dress-rehearsal mission under the name Kosmos-238, re-opening the door for cosmonaut spaceflight.

Despite three successful flights in a row, only a single cosmonaut, Georgy Beregovoy was approved to fly the Soyuz-3 spacecraft to dock with the unmanned spacecraft. The unmanned vehicle was launched first on October 25, 1968, and was announced as Soyuz-2. As the unmanned spacecraft re-appeared over Tyuratam, nearly 24 hours later, the Soyuz-3 with Georgy Beregovoy onboard lifted off from a near-by launch pad at 11:34 Moscow Time.

The rocket carrying Soyuz-3 had performed so perfectly that it inserted the ship into orbit just 11 kilometers from the unmanned Soyuz-2. The Igla (needle) rendezvous system onboard Soyuz-3 quickly zeroed in on its target and began automated intercept maneuvers. The final rendezvous and docking maneuvers fell on the night side of the Earth and out of range of Soviet ground stations.

In accordance with the flight program, at a distance of 200 meters, Beregovoy switched to manual control and steered his ship toward docking, however at the last moment, when the duo was separated by a distance of around 30 or 40 meters, the Soyuz-2 suddenly made an avoidance maneuver. Even more puzzling to the pilot, the Soyuz-2 turned away again during the second approach in daylight, even though the spacecraft had been programmed to maintain the stable position and point its docking port toward the approaching ship.

When mission control finally had had a chance to downlink and analyze the latest telemetry from orbit, the controllers found Soyuz-3 critically low on propellant supplies even for a braking maneuver, let alone another docking attempt.

The mission officials immediately switched into the landing mode: the unmanned Soyuz-2 was guided to a normal touchdown on October 28 and Beregovoy followed onboard Soyuz-3 two days later. His descent module landed 70 kilometers north of the Kazakh city of Karaganda at 10:25 Moscow Time on October 30. The Soyuz-3 mission lasted three days 22 hours and 50 minutes.

The following investigation revealed that the entire automated docking process worked as prescribed, however by the time Beregovoy switched to manual control, there was some mismatch in the position of two ships along the roll axis. Intending to fix the orientation, Beregovoy banked the spacecraft so much that it ended up in an upside down position relative to main axis of its target. As a result, the automated stabilization system onboard Soyuz-2 detected the error and tried to orient the ship "correctly" for docking.

Although different colors of lights on the tips of solar panels of Soyuz-2 were designed to give the pilot an idea about the orientation of its target, the darkness of night and effects of weightlessness likely contributed to Beregovoy's poor situational awareness. Records also showed that Beregovoy had consistently earned lower scores than his younger backups—Vladimir Shatalov and Boris Volynov—during training in a rudimentary docking simulator.

All these details became publicly known only decades later, but at the time, the official Soviet press declared the Soyuz-3 mission a great success, while the Kremlin bestowed Beregovoy with its usual honors. The Soyuz engineers could comfort themselves with the thought that the second-generation Soviet spacecraft had finally successfully carried a cosmonaut into space and back to Earth.