Soyuz-2 (rocket)

Soyuz-2, GRAU index 14A14, is the collective designation for the new version of the Russian Soyuz rocket. In its basic form, it is a three-stage carrier rocket for placing payloads into low Earth orbit. The first stage boosters and two core stages feature uprated engines with improved injection systems, compared to the previous versions of the Soyuz. Digital flight control and telemetry systems allow the rocket to be launched from a fixed launch platform, whereas the launch platforms for earlier Soyuz rockets had to be rotated as the rocket could not perform a roll to change its heading in flight.

Soyuz-2 is often flown with an upper stage, which allows it to lift payloads into higher orbits, such as Molniya and Geosynchronous orbits. The upper stage is equipped with independent flight control and telemetry systems from those used in the rest of the rocket. The NPO Lavochkin manufactured Fregat is the most commonly used upper stage.

Soyuz-2 rockets are currently launched from LC-31 at the Baikonur Cosmodrome, and LC-43 at the Plesetsk Cosmodrome, launch facilities shared with earlier R-7 derived rockets, including the Soyuz-U and Molniya.

Commercial Soyuz-2 flights are contracted by Starsem, and are currently launched from LC-31 at Baikonur. These will move to a new site, ELS (l'Ensemble de Lancement Soyouz), which has been built at the Guiana Space Centre on the northern coast of South America. The Soyuz-2 is expected to be able to deliver 2.8-3.5 tonnes to GTO from this site. The first launch was October 21, 2011, for two European space navigation satellites.^[1] : three hours and 49 minutes after blast-off, the ESA announced that the two Galileo satellites had successfully reached their final orbit 23,222 kilometres above Earth, and that their launch had been a complete success.

The Soyuz-2 has replaced the Molniya-M^[2] and is starting to replace the Soyuz-U and Soyuz-FG rockets which are currently in service alongside it, as they are expected to be phased out from 2014 onwards.^[3][4]

Variants

Soyuz-2 family includes 2.1a, 2.1b and 2.1v. The first two variants are modifications to the Soyuz-U launcher. The latter is a "light" version without side boosters.

When launched from ELS site, the Soyuz-2 will always be mated with ST-type fairing. This version will be called Soyuz-ST or Soyuz-STK, where additional "K" indicates special measures taken for preparing and launching the rocket in hot and humid conditions.

Soyuz 2.1a

The 2.1a version includes conversion from analog to digital flight control system and uprated engines on the booster and the first stage with improved injection systems. The new digital flight control and telemetry systems allow to launch the rocket from a fixed launch platform and adjust its heading in flight. A digital control system also enables to launch larger commercial satellites with wider and longer fairings such as ST-type fairing. These fairings introduce too much aerodynamic instability for the old analog system to handle. This stage continues to use the RD-0110 engine.

The 2.1a/ST version is sometimes called Soyuz-STA. The first launch, from Guiana, (December, 12, 2011 for Pleiades 1 satellite, SSOT, ELISA (4 satellites)) was a success.

Soyuz 2.1b

The 2.1b version adds an upgraded engine (RD-0124) with improved performance to the second stage.

The 2.1b/ST version is sometimes called Soyuz-STB. The first launch, from Guiana, was a success (October, 21 2011), for the first two Galileo IOV satellites.

Soyuz 2.1v

First draft of the 2.1v version was finished in 2009. It will be a "light" version of the Soyuz-2 without the side boosters (blocks B, V, G and D). Block A engine will be replaced by a more powerful one NK-33-1. The new launcher will be able to deliver up to 2.8 tonnes in low Earth orbit.^[5]

Suborbital test flight

On 8 November 2004, at 18:30 GMT (21:30 Moscow Time), the first Soyuz-2 carrier rocket, in the Soyuz-2.1a configuration, was launched from the Plesetsk Cosmodrome in Russia. The rocket followed a sub-orbital trajectory, with the third stage and boilerplate payload re-entering over the Pacific Ocean.

Commercial launches

MetOp-A

The first attempt at launching a Soyuz-2 to orbit, with the MetOp-A satellite, occurred on 17 July 2006. It was scrubbed two hours before the launch by an automatic sequence, after the onboard computer failed to check the launch azimuth. Fuelling of the rocket was underway at the time, and all launch complex equipment and on-board preliminary checks had proceeded without incident. The rocket was left fuelled on the launch pad, for the next attempt on 18 July. Launch was eventually conducted on 19 October.

Launch history

See also

• Soyuz programme
• Starsem

References

External links

• Encyclopedia Astronautica article on Soyuz 2.1
• Encyclopedia Astronautica article on Soyuz 2.1/Fregat
• European Space Agency about Soyuz-ST (Russian name Soyuz-STK)
• Soyuz User's Manual, from Starsem
• Soyuz-2 launch vehicle, Russian Federal Space Agency