R7

R7 or R-7 may be:

R-7 (rocket family)

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

History

When Soviet nuclear warheads got lighter, the R-7 turned out to be impractical as a ballistic missile. It was not necessary to launch such heavy payloads in a military application. The rockets remained useful in the Soviet and then Russian space programmes with long term development. The R-7 family consists of both missiles and orbital carrier rockets. Derivatives include the Vostok, Voskhod and Soyuz rockets, which as of 2014 have been used for all Soviet, and later Russian manned 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.

Later modifications were standardised around the Soyuz design. The Soyuz-U, Soyuz-FG and Soyuz-2 are currently in use. The Soyuz-U and FG are to be retired over the next few years, in favour of the Soyuz-2. R-7 rockets are launched from the Baikonur Cosmodrome and the Plesetsk Cosmodrome. A third launch site, at the Guiana Space Centre in French Guiana, was to open in 2009 but the first Soyuz launch had been postponed several times. The first launch from Guiana Space centre took place on October 21, 2011. Guiana will be used primarily for commercial launches to geosynchronous orbit, taking advantage of the launch site's proximity to the equator.

R-7 Semyorka

The R-7 (Russian: Р-7 «Семёрка») was a Soviet missile developed during the Cold War, and the world's first intercontinental ballistic missile. The R-7 made 28 launches between 1957 and 1961, but was never deployed operationally. A derivative, the R-7A, was deployed from 1959 to 1968. To the West it was known by the NATO reporting name SS-6 Sapwood and within the Soviet Union by the GRAU index 8K71. In modified form, it launched Sputnik 1, the first artificial satellite, into orbit, and became the basis for the R7 family which includes Sputnik, Luna, Molniya, Vostok, and Voskhod space launchers, as well as later Soyuz variants.

The widely used nickname for the R-7 launcher, "semyorka", means "the 7" in Russian.

Description

The R-7 was 34 m (112 ft) long, 3.02 m (9.9 ft) in diameter and weighed 280 metric tons (280 long tons; 310 short tons); it had two stages, powered by rocket engines using liquid oxygen (LOX) and kerosene and capable of delivering its payload up to 8,800 km (5,500 mi), with an accuracy (CEP) of around 5 km (3.1 mi). A single thermonuclear warhead was carried with a nominal yield of 3 megatons of TNT. The initial launch was boosted by four strap-on liquid rocket boosters making up the first stage, with a central 'sustainer' motor powering through both the first and the second stage. Each strap-on booster included two vernier thrusters and the core stage included four. The guidance system was inertial with radio control of the vernier thrusters.