How does the Soyuz launch system work?

The Soyuz launch system – which consists of a Soyuz Launch Complex, a launch vehicle and, when astronauts are involved, a Soyuz TMA spacecraft – is the main means crew and equipment have been taken to and from the International Space Station (ISS) for the last decade. To date the system has made over 40 launches and 100 per cent have been successful, with a mix of astronaut-ferrying spacecraft, cargo and satellites transported into low Earth orbit.

The two primary Soyuz launch system facilities are located at the Baikonur Cosmodrome in Kazakhstan and the Guiana Space Centre in French Guiana. Both sites can be used to transport astronauts, cargo and satellites off Earth, however Baikonur has been the principal launch site for TMA spacecraft and Guiana for satellites. Each site utilises Soyuz-family launch vehicles – ie the Soyuz-FG and Soyuz-2 – as well as a Soyuz Launch Complex (see boxout over the page for a detailed breakdown of the latter).

What is arguably key to the Soyuz’s overall popularity is the Soyuz-FG launch vehicle. All three stages of this rocket use the same type of fuel, which is a highly efficient mix of liquid oxygen and kerosene. In partnership with four strap-on boosters that can be jettisoned once spent, as well as a protective launch abort system designed to rescue the crew in an emergency, the launcher carries multimillion- pound equipment and highly trained astronauts safely to and from space.

Indeed, the Soyuz system is now so slick that on 29 May 2013, Expedition 36 reached the ISS in a world record-breaking time of only five hours and 39 minutes. To put that in context, that’s an hour faster than the average car drive between London and Edinburgh!

The Soyuz spacecraft

Soyuz components

Solar panel

Bolted on to the side of the service module are an array of orientation sensors and a pair of extendable solar panels. The panels are faced towards the Sun by rotating the spacecraft, with the cells supplying energy to the service module’s internal battery stack.

Orbital module

The orbital module is a habitable section of the spacecraft and carries any equipment that will not be needed for re-entry. This includes experiments, cargo and cameras. A door between the orbital and re-entry module means it can function as an airlock too. Dining and toilet facilities are also located here.

Re-entry module

A second habitable section, the re-entry module – unlike the orbital module – is used for the spacecraft’s return descent. As such, it is covered with a heat-resistant composite material. Additional equipment can be stored in this section, as well as seats for three astronauts.

On-board sensors

A range of sensors are packed into the Soyuz TMA, including Earth, Sun and thermal sensors, plus an assortment of antennas for communication (both audio and visual varieties). The bulk of these are located on or in the service module.

Life support

Soyuz can provide life support for three crew members for up to 30 days. The life support system creates a nitrogen/oxygen atmosphere at sea level partial pressures and is capable of recycling carbon dioxide and water

Service module

At the back is the service module. This contains the systems for temperature control, electric power generation, long-range radio communications, radio telemetry and orientation control. A non-pressurised compartment in the module holds the main engine and liquid-fuel propulsion systems.

Soyuz launch system
The Soyuz launch system

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Plus, take a look at:

Interview with an astronaut 

Why was the Space Shuttle retired?

NASA signs up SpaceX to take astronauts to the ISS