Soyuz/ST configuration with MetOp


The Soyuz/ST Fregat rocket is integrated at TsSKB-PROGRESS in Samara, Russia. The launcher procurement is undertaken under EUMETSAT responsibility, through Starsem, who provide both the technical interface and offer state of the art integration facilities at the launch site, the Baikonur Cosmodrome in Kazakhstan.

About Soyuz

The Soyuz rocket was first used in November 1963 and has since flown more than 1650 times. A success rate of more than 97% makes it one of the most reliable launch vehicles in the world. It is a man rated launcher regularly used for Space Station servicing.

The Soyuz/ST rocket on the launchpad
The Soyuz rocket usually comprises three stages:
  • Stage 1: a lower portion consisting of four conical boosters grouped around stage 2
  • Stage 2: a cylindrical central core
  • Stage 3: an upper stage with a payload adapter and fairings

The four side boosters (Stage 1) and the central core (Stage 2) ignite at the same time before lift off. After the first stage has used all its fuel it separates and the second stage continues to burn. All three stages use liquid oxygen and kerosene fuel.

For the MetOp launch, a fourth stage, known as Fregat, is also to be used. Its main engine is ignited twice to raise the satellite orbit around the Earth to a nominal 820 km. The Fregat uses hydrazine (UDMH) and nitrogen tetroxide as fuel. It is capable of up to 12 restarts.

The launcher for MetOp is the Soyuz/ST which is an enhancement to the basic Soyuz launch vehicle.


The Soyuz/ST has three main enhancements:
  • capacity for an increased payload volume because of its 4.110 m diameter class fairing
  • an upgraded avionics system, featuring a digital control system, giving it greater flexibility
  • a strengthened third stage to cater for the change in fairing and increased payload capacity

Further for MetOp a new lightweight Fregat (fourth stage) is used saving approximately 100 kg from the original design.

Soyuz facts
Lift off weight 304 tonnes
Propellant weight 279.5 tonnes
Height 43.5 m
Maximum diameter 10.3 m
Thrust (in vacuum)
first stage 4964 kN
second stage 997 kN
third stage 298 kN
fourth stage 19.6 kN
Payload capability (to 832 km) up to 4.3 tonnes (with Fregat)
Soyuz Stage-3 separation

The Fregat upper stage

The Fregat is a fourth stage which has been under development by NPO Lavotchkin since 1992. Its first qualification flight was in January 2000. Although the Fregat is relatively new, each individual component has successfully flown many times. The main engine has already had more than 30 flights, all successful.

Fregat facts
Diameter 3.35 m
Height 1.5 m
Lift off weight 6415 kg
Propellant weight 5350 kg
fuel Unsymmetrical dimethyl-hydrazine (UDMH)
oxidizer Nitrogen tetroxide
Main engine thrust 19620 N
Main engine specific impulse 328 seconds
Baikonur Cosmodrome
Sunset over the launch pad at Baikonur

Baikonur Cosmodrome

Baikonur Cosmodrome is located at 45.6°N latitude and 63.4°E longitude in the flat grasslands of Central Asia in the former Soviet Republic of Kazakhstan. The area has a continental climate, with long, cold winters and hot, dry summers.

Construction of the secret missile site began in 1955. The first artificial satellite, Sputnik 1, and first human in space, Yuri Gagarin, were launched from Baikonur. All subsequent Russian manned missions have lifted off from there, as well as geostationary, lunar, planetary, and many ocean surveillance missions.

Until recently, the name Baikonur was misleading. The former Soviet Union used the name and co-ordinates of a small mining town, Baikonur, to describe its secret rocket complex. This was done intentionally to hide the true location of the launch complex. In fact, the launch complex is about 230 miles south-west of Baikonur town, near the railway station and village of Tyuratam and close to Leninsk city. However, in 1998, Leninsk city was renamed Baikonur city.

The MetOp spacecraft is delivered to the cosmodrome by air and integrated with the Fregat stage inside a modern payload processing facility.

The strap-on boosters and stages of the Soyuz booster are assembled horizontally in the large Vehicle Assembly Building. The entire launch vehicle, with its payload, is then transported by rail to the launch pad, where it is vertically erected over a large flame deflector pit.

Last update: 3 April 2012

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