Soyuz 10 (Russian: Союз 10, Union 10) was launched on 22 April 1971 as the world's first mission to the world's first space station, the Soviet Salyut 1. The docking was not successful and the crew returned to Earth without having entered the station. It would be the first of numerous docking failures in the Soviet space station program.

Soyuz 10 was launched on 22 April 1971 to dock with Salyut 1. The spacecraft was the first of the upgraded Soyuz 7K-OKS, featuring the new "probe and drogue" docking mechanism with internal crew transfer capability, intended for space station visits.

The cosmonauts Vladimir Shatalov, Aleksei Yeliseyev, and Nikolai Rukavishnikov were able to navigate their Soyuz 10 spacecraft to the Salyut 1 station, yet during docking they ran into problems. The automatic control system failed during approach due to a serious design oversight - when soft dock was performed, the computer sensed an abnormality in the spacecraft's alignment and began firing the attitude control jets to compensate. With Soyuz 10 being pushed to one side by the attitude control system, it became impossible to achieve hard dock and large quantities of propellant were expended doing so. The docking attempt was called off, but further problems occurred when the probe would not come out of the space station's docking cone. The obvious solution was to simply jettison the orbital module and leave it attached to Salyut 1, but this would make it impossible for future Soyuz missions to dock and thus the space station would have to be abandoned. Eventually, ground controllers figured out that the cosmonauts could throw a circuit breaker in the docking mechanism, as interrupting the power supply would cause the probe to automatically retract. This procedure worked and undocking was completed. The automatic control system would be redesigned on future Soyuz spacecraft.

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