World Library  
Flag as Inappropriate
Email this Article


Soyuz-U (Soyuz-U/Ikar; Soyuz-U/Fregat)

The Soyuz TMA-3 vehicle launches from the Baikonur Cosmodrome in Kazakhstan October 18, 2003
Function Orbital carrier rocket
Manufacturer TsSKB-Progress
Country of origin Soviet Union (Russia)
Height 51.1 m for Soyuz-U; 47.3 m for Soyuz-U/Ikar and 46.7 m for Soyuz-U/Fregat
Diameter 3 m [1]
Mass 313,000 kg (Soyuz-U); 308,000 kg (Soyuz-U/Ikar and Soyuz-U/Fregat)
Stages 2 (Soyuz-U) or 3 (Soyuz-U/Ikar and Soyuz-U/Fregat)
Payload to LEO 6,900 kg from Baikonur and 6,700 kg from Plesetsk
Associated rockets
Family R-7 (Soyuz)
Derivatives Soyuz-U2
Launch history
Status Active
Launch sites LC-1 & LC-31, Baikonur
LC-16 & LC-43, Plesetsk
Total launches 745
Successes 724
Failures 21
First flight 18 May 1973[2]
Notable payloads Soyuz spacecraft
Progress spacecraft

The Soyuz-U launch vehicle (LV) is an improved version of the original Soyuz LV. Soyuz-U is part of the R-7 family of rockets based on the R-7 Semyorka missile. Members of this rocket family were designed by the TsSKB design bureau and constructed at the Progress Factory in Samara, Russia. (These two are now a united company, TsSKB-Progress). The first Soyuz-U flight took place on 18 May 1973, carrying as its payload Kosmos 559, a Zenit military surveillance satellite.[2]

The earlier Soyuz 11A511 was the first attempt at creating a standardized R-7 core in place of the numerous variations that had been used up to 1966 and starting that year, the 11A511 Blok I and strap-on boosters were added to the Voskhod (11A57), Vostok-2 (8A92), and Molniya-M (8K78M) vehicles as well as minor R-7 variants flown once or twice for specialized payloads.

Beginning in 1973, the uprated 11A511U core was introduced for the R-7 family although adoption across the board was not complete until 1977 when the existing stock of 11A511-derived boosters was used up.

Soyuz-U is still in use today, making several launches a year. Production of R-7 derived launch vehicles peaked in the late 1970s-early 1980 at 55-60 a year. Soyuz-U holds the world record of highest launch rate in a year in 1979 with 47 flights.


  • Versions 1
  • Human spaceflight 2
  • Recent missions 3
  • References 4
  • External links 5


A Soyuz-U prepares to launch Soyuz 19.

There are two versions of Soyuz-U with upper stages that has flown, Soyuz-U/Ikar and Soyuz-U/Fregat.

Soyuz-U/Ikar uses Ikar as its 3rd stage, produced by the Progress State Research and Production Rocket Space Center, TsSKB-Progress. Ikar is used to deliver various payloads with masses of 750 kg to 3920 kg to heights 250 km to 1400 km. The performance of the Ikar upper stage is lower than that of the Fregat upper stage, but it is more precise in maneuvering and it can operate autonomously longer.

Soyuz-U/Fregat uses Fregat as its 3rd stage, developed and produced by Lavochkin Association in Khimki.

An older variant of Soyuz-U, the Soyuz-U2 launcher, had the same hardware as the basic Soyuz-U. Instead of standard RP-1, it used a high energy, synthetic version, Syntin, as the first stage fuel. This variant, mainly used for reconnaissance satellites, last flew in 1996, after production of Syntin ended due to cost reasons.

Soyuz-U was the basic platform for the development of the Soyuz-FG launch vehicle, which uses an all-new first stage.

In the future both Soyuz-U and Soyuz-FG will be replaced by the Soyuz-2 launch vehicle.

Human spaceflight

The first use of a Soyuz-U to launch a crewed mission took place 2 December 1974, when the Soyuz 16 crew was launched in preparation for the Apollo-Soyuz Test Project (ASTP). Soyuz 19, which as part of the ASTP docked with the last Apollo spacecraft ever flown, was also launched by a Soyuz-U rocket.[2]

On 6 July 1976 a Soyuz-U launched Soyuz 21, which took a crew of two to the Salyut 5 space station. Many subsequent space station crews were launched on Soyuz-U launchers. The final crewed mission to utilize the Soyuz-U was Soyuz TM-34, a Soyuz ferry flight to the International Space Station.

Recent missions

Since the early 2000s, Soyuz-U vehicles have been used by the Russian Federal Space Agency primarily to launch Progress-M robotic cargo spacecraft on resupply missions to the International Space Station (ISS).

Although the Soyuz-U is generally very reliable, occasional failures have happened, such as the October 2002 launch of a Foton satellite which crashed near the pad at Plesetsk after the Blok D strap-on booster suffered an engine malfunction. One person on the ground was killed.

A recent Soyuz-U mission failed to launch Progress M-12M to the ISS on 24 August 2011, when the upper stage experienced a problem and broke up over Siberia. It was the first time a Progress spacecraft had failed to reach orbit.

On 12 April 2015 Soyuz-U was declared to be obsolete. Its production has been stopped, and usage of the rocket will end when all stored vehicles have been launched, mostly with Progress cargo ships. The final Soyuz-U rockets are expected to be launched in 2015, at which point its role will be taken over by the newer Soyuz-2.[3] The transition to Soyuz-2 was forced due to political reasons, because some parts for the guidance system were imported from Ukraine.


  1. ^
  2. ^ a b c Mark Wade (26 March 2001). "Soyuz 11A511U". Friends and Partners. 
  3. ^ "Soyuz U - Launch Vehicle". Spaceflight 101. Retrieved 8 July 2015. 

External links

  • (PDF) Soyuz Launch Vehicle Users Manual
  • entry on Soyuz-U / 11A511U
  • entry on Soyuz-U2 / 11A511U2
  • Russian Federal Space Agency about Soyuz-U
  • Russian Federal Space Agency about Soyuz-U/Ikar
  • Russian Federal Space Agency about Soyuz-U/Fregat
  • Russian Federal Space Agency about Soyuz-U2
  • LV's manufacturer TsSKB-Progress about Soyuz-U (in Russian)
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.