Jump to content

R-7 (rocket family)

From Wikipedia, the free encyclopedia
(Redirected from Korolyov cross)
R-7 Semyorka and its variants used as launchers in the early Soviet space program

The R-7 (Russian: Р-7) family of rockets is a series of rockets, derived from the Soviet R-7 Semyorka, the world's first intercontinental ballistic missile (ICBM). More R-7 rockets have been launched than any other family of large rockets.

Under the direction of the rocket pioneer Sergey Korolyov, the Soviet Union during the 1950s developed an ICBM that was capable of delivering a heavy nuclear weapon to American targets. That ICBM, called the R-7 or Semyorka ("Number 7"), was first successfully tested on August 21, 1957. Because Soviet nuclear warheads were based on a heavy design, the R-7 had significantly greater weight-lifting capability than did initial U.S. ICBMs. When used as a space launch vehicle, this gave the Soviet Union a significant early advantage in the weight that could be placed in orbit or sent to the Moon or nearby planets. There have been a number of variants of the R-7 with an upper stage, each with a different name, usually matching that of the payload, and each optimized to carry out specific missions. An unmodified R-7 was used to launch the first Soviet satellite, Sputnik 1, on October 4, 1957, and an R-7 variant, the Vostok, launched the first Soviet cosmonauts, among them Yuri Gagarin, who on April 12, 1961, became the first human to orbit Earth. Other variants include the Voshkod, used to launch reconnaissance satellites, and the Molniya, used to launch communications satellites. A multipurpose variant, the Soyuz, was first used in 1966 and, with many subsequent variants and improvements, is still in service. This family of launch vehicles has carried out more space launches than the rest of the world's launch vehicles combined.

When Soviet nuclear warheads became lighter, the R-7 turned out to be impractical as a ballistic missile, and there were no other heavy payloads with a military application. However, long-term development has made the rockets useful in the Soviet, and later, Russian space programmes. Their purpose shifted primarily to launching satellites, probes, crewed and uncrewed spacecraft, and other non-threatening payloads. The R-7 family consists of both missiles and orbital carrier rockets. Derivatives include the Vostok, Voskhod and Soyuz rockets, which as of 2022 have been used for all Soviet, and later Russian human spaceflights. The type has a unique configuration where four break-away liquid-fueled engines surround a central core. The core acts as, in effect, a "second stage" after the other four engines are jettisoned. These rockets are expendable.

Later modifications were standardised around the Soyuz design. The Soyuz-2 is currently in use.

The Soyuz-FG was retired in 2019 in favour of the Soyuz-2.1a.[1] R-7 rockets are launched from the Baikonur Cosmodrome, Plesetsk Cosmodrome, Guiana Space Centre (from 2011 to 2022, see Soyuz at the Guiana Space Centre), and the Vostochny Cosmodrome (first launch 2016).

Summary of variants

[edit]

All the R-7 family rockets are listed here by date of introduction. Most of the early R-7 variants have been retired. Active versions (as of 2022) are shown in green.

Name GRAU
index
Function N° Core
Stages[a]
Maiden flight Final flight Launches[b] Remarks
Total Success Failure
(+ partial)
R-7 Semyorka 8K71 ICBM 1 15 May 1957 27 February 1961 27 18 9 World's first ICBM
Sputnik-PS 8K71PS Carrier rocket 1 4 October 1957 3 November 1957 2 2 0 World's first carrier rocket
Launched Sputnik 1 and Sputnik 2
Sputnik 8A91 Carrier rocket 1 27 April 1958 15 May 1958 2 1 1 Launched Sputnik 3
Luna 8K72 Carrier rocket 2 23 September 1958 16 April 1960 9 2 7 Launched first Lunar probes
R-7A Semyorka 8K74 ICBM 1 23 December 1959 25 July 1967 21 18 3 The only operational ICBM version. Improved range and guidance system. Only 6 launch positions were available. Used as a base for 11A57 and later mods
Vostok-L 8K72L Carrier rocket 2 15 May 1960 1 December 1960 4 3 1 Variant of Luna, used to launch prototype Vostok spacecraft
Molniya 8K78 Carrier rocket 3 20 January 1960 3 December 1965 26 12 14 Designed to send payloads out of LEO
Vostok-K 8K72K Carrier rocket 2 22 December 1960 10 July 1964 13 11 2 Used for crewed Vostok missions
First rocket to launch a man into space
Molniya-L 8K78L Carrier rocket 3 Unbuilt
Vostok-2 8A92 Carrier rocket 2 1 June 1962 12 May 1967 45 40 5 Used for launching Zenit reconnaissance satellites throughout the 1960s
Polyot 11A59 Carrier rocket 1 1 November 1963 12 April 1964 2 2 0
Voskhod 11A57 Carrier rocket 2 16 November 1963 29 June 1976 300 277 23 Launched crewed Voskhod 1 and Voskhod 2 missions
Molniya-M 8K78M Carrier rocket 3 19 February 1964 30 September 2010[2] 297 276 21 Improved version of Molniya
Vostok-2M 8A92M Carrier rocket 2 28 August 1964 29 August 1991 94 92 2 Modified version for launching Meteor weather satellites into higher orbits
Soyuz/Vostok 11A510 Carrier rocket 3 27 December 1965 20 July 1966 2 2 0 Launched with prototype US-A satellites
Soyuz 11A511 Carrier rocket 2 28 November 1966 24 May 1975 30 28 2 Launched several crewed Soyuz missions
Soyuz-B 11K55 Carrier rocket 2 Unbuilt
Soyuz-V 11K56 Carrier rocket 2 Unbuilt
Soyuz-R 11A514 Carrier rocket 2 Unbuilt
Soyuz-L 11A511L Carrier rocket 2 24 November 1970 12 August 1971 3 3 0 Created to test the LK lunar lander in LEO
Soyuz-M 11A511M Carrier rocket 2 27 December 1971 31 March 1976 8 8 0 Built to launch crewed Soyuz 7K-VI spacecraft, eventually used to launch reconnaissance satellites
Soyuz-U 11A511U Carrier rocket 2 or 3 18 May 1973 22 February 2017 786 765 22[3] Single most launched carrier rocket ever built
Used for a number of crewed Soyuz launches
Soyuz-U2 11A511U2 Carrier rocket 2 23 December 1982 3 September 1995 72 72 0 Used for a number of crewed Soyuz launches
Soyuz-FG 11A511U-FG Carrier rocket 2 or 3 20 May 2001 25 September 2019 70 69 1 Used for crewed Soyuz launches, the final launch was the Soyuz MS-15 on 25 September 2019.
Soyuz-2.1a / STA 14A14A Carrier rocket 2 or 3 8 November 2004 Active 75 72 2+1p Used for crewed Soyuz launches from Soyuz MS-16 on 9 April 2020. In August 2019 the booster lofted the uncrewed Soyuz MS-14 into orbit in order to test the spacecraft on the new rocket.
Soyuz-2.1b / STB 14A14B Carrier rocket 2 or 3 27 December 2006 Active 90 87 2+1p
Soyuz-2-1v 14A15 Carrier rocket 2 28 December 2013 Active 12 11 1p 1st stage uses a completely new design utilizing surplus NK-33 engines from the Moon N-1 launcher and no boosters.
  1. ^ Not including boosters
  2. ^ As of 22 May 2020

Korolev Cross

[edit]
Korolev cross, Soyuz TMA-04M

The Korolev Cross is a visual phenomenon observed in the smoke plumes of the R-7 series rockets during separation of the four liquid-fueled booster rockets attached to the core stage.[4] As the boosters fall away from the rocket, they pitch over symmetrically due to aerodynamic forces acting upon them, forming a cross-like shape behind the rocket. The effect is named after Sergei Korolev, the designer of the R-7 rocket. When the rocket is launched into clear skies, the effect can be seen from the ground at the launch site.

See also

[edit]

References

[edit]
  1. ^ Zak, Anatoly. "Soyuz-FG's long road to retirement". Russian Space Web. Retrieved 19 October 2017.
  2. ^ Mu, Xuequan (1 October 2010). "Russia sends military satellite into space". Xinhua. Archived from the original on October 3, 2010. Retrieved 30 September 2010.
  3. ^ In 1983, flight Soyuz T-10a caught fire on the launch pad before the end of the countdown, so it is not counted in the list of launches; this is why adding successes and failures yields 787 launches instead of 786.
  4. ^ NASA TV coverage of Soyuz TMA-12 launch
[edit]