How the Soviet Union built the road to the stars - The R7 Rocket

Video from the channel Escape Velocity about R-7 Semyorka, linked on its Above Ten Thousand entry. Duration: 12:57. Language: English. Video type: Documentary.

An explainer on the history of the R-7 family, from its origin as an intercontinental ballistic missile to becoming the basis of the Vostok, Voskhod, Molniya and Soyuz launchers. It pays attention to its engineers, the cosmonauts and the internal rivalries of the Soviet programme.

The video places the origin in the 1950s: the United States could reach Moscow from its air bases and the USSR had no equivalent means. Drawing on experience with captured V-1s and V-2s, the R-1 copied the V-2 and the R-2 extended its range. In the early part of that decade Sergei Korolev was tasked with a new rocket with a range of 8,000 km and a 3 t payload, a figure dictated by the weight of Soviet nuclear warheads. When those warheads became lighter, the R-7 was left with power to spare, and that gave the USSR an edge in the space race. The video then describes the decline: Korolev's death in January 1966, that of Vladimir Komarov aboard Soyuz 1 and that of Gagarin in 1968, against the backdrop of the American Moon landing of 1969.

The R-7 had two stages and five engines: a central RD-108 with four verniers and four boosters with RD-107 and two verniers each, all ignited at liftoff. At around the minute-and-a-half mark the boosters separated, forming the "Korolev cross". They burned liquid oxygen and kerosene with mixture control, the work of Valentin Glushko. The first launch, in 1957, ended in an explosion; on 21 August an R-7 successfully carried a simulated warhead. Then came Sputnik, Laika aboard Sputnik 2, the Luna 1, 2 and 3 probes, Belka and Strelka and, on 12 April 1961, Gagarin aboard Vostok 1. The Vostok added a third stage with the RD-109 and raised the payload to 4.5 t. The Voskhod carried Alexei Leonov on the first spacewalk, and in 1966 the Soyuz flew for the first time.