Soyuz-U

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Soyuz-U (Soyuz-U/Ikar; Soyuz-U/Fregat)
Soyuz TMA-3 launch.jpg
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)
Size
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)
Capacity
Payload to LEO 6,900 kg from Baikonur and 6,700 kg from Plesetsk
Associated rockets
Family R-7 (Soyuz)
Derivatives Soyuz-U2
Soyuz-FG
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[edit]

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[edit]

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[edit]

Lately Soyuz-U vehicles have been used by the Russian Federal Space Agency mostly with Progress-M robotic cargo spacecraft to resupply the International Space Station (ISS).

Although the 11A511U is generally very reliable, occasional failures have happened including the October 2002 launch of a Foton satellite which crashed near the pad at Plesetsk after the Blok D strap-on suffered an engine malfunction. One person on the ground was killed.

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

References[edit]

  1. ^ http://www.astronautix.com/lvs/soyuzu.htm Astronautix.com
  2. ^ a b c Mark Wade (26 March 2001). "Soyuz 11A511U". Friends and Partners. 

External links[edit]