Orbital Focus - International Spaceflight Facts and Figures
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Soyuz 4 and Soyuz 5

Tyneside, UK
2024 Jun 15
Saturday, Day 167

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First Space Station In Orbit

On January 16, 1969, for the first time in history two spacecraft, manually controlled were docked. They were Soyuz-4 and Soyuz-5. As a result, a manned space station of four compartments for the crew was assembled. The total internal volume of the space station was 18 cubic metres.

The problem of building such stations to enable researchers to work in orbit around the Earth for a prolonged period of time, or to be used as an intermediate stage in interplanetary flights, has engaged the attention of scientists for some time. For to launch a "heavy" satellite that has been assembled on Earth presents great difficulties, involving the need to build a giant launch vehicle with engines having a thrust bordering on the fantastic. The solution to the problem lies in the assembly of "heavy" satellites in orbit. Component units will be delivered into orbit consecutively.

Of course, all the units must he launched into the same orbit, concentrated in one place and then assembled.

Prior to performing the most important part of the mission involving docking, the crew of Soyuz-5 made the necessary correction of the orbit. Soyuz-4 was the "active" spacecraft. With the use of the on-board propulsion system it performed all manoeuvres required for a rendezvous and docking.

First, the proper attitude of the spacecraft in space was attained. Before switching on the on-board engine the spacecraft was turned about the centre of mass into a specific position.

Within the effective range of rendezvous radars of the spacecraft, the approach was controlled automatically. The radar of the "passive" spacecraft kept sending impulses which were received by the "active" spacecraft. Throughout the process Soyuz-4 performed the manoeuvres necessary for a rendezvous, whereas Soyuz-5 "followed" the active one and changed its attitude accordingly.

Thus the lateral axis of Soyuz-5 was constantly directed at Soyuz-4. In other words, Soyuz-4 was within the "field of visibility" of Soyuz-5.

The impulses from the radar of the "active" spacecraft were sent to computers, which in turn issued the necessary signals that switched on the appropriate engines. Such manoeuvres are highly complicated owing to the strict requirement for effective approach with minimum consumption of fuel.

When the distance between the spacecraft was 100 metres, manual-controlled approach started. Vladimir Shatalov, pilot of the "active" spacecraft, followed the other spacecraft through the optical observation systems and switched on and off small-thrust rockets. By means of the control stick on the left-hand side he adjusted the speed, accelerating or decelerating the spacecraft, and turning it to the right or to the left. With the aid of the control stick on the right-hand side the cosmonaut turned the spacecraft around the centre of mass.

The distance between the spacecraft was reduced to 25 metres. The spacecraft approached each other at a speed of 25 centimetres per second. The docking unit of the "active" spacecraft was then inserted into the appropriate reception unit of the "passive" spacecraft. After that the spacecraft were fastened tight mechanically and electrically.

Now the cosmonauts could contact each other not only through radio communication channels, but also by means of internal telephone lines. The world's first orbital space station with a crew of four cosmonauts started its operation.
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