RKTs Progress

Catalog — Rockets

• 2004

  Soyuz 2.1a

  The Soyuz-2.1a is the baseline model of the Russian Soyuz-2 launcher family — that is, a specific configuration within that series rather than a standalone rocket. Soyuz-2 as a whole is a series of expendable medium-lift launch vehicles, the seventh major iteration of the Soyuz family and itself a descendant of the R-7 missile. It is developed and built by the Progress Rocket Space Centre (RKTs Progress) in Samara. What sets the 2.1a apart from its predecessors is the introduction of the family's digital flight control system, replacing the analogue avionics of earlier Soyuz rockets. The new avionics are physically lighter, allow in-flight trajectory adjustments and support larger payload fairings, opening the way to heavier commercial satellites. The variant also uses the upgraded RD-107A and RD-108A engines. Its third stage retains the RD-0110 engine of the classic Soyuz vehicles, but with enlarged propellant tanks and a revised structure shared with the Soyuz-2.1b; together these changes raised payload capacity by about 300 kg. Compared with the 2.1a, the 2.1b swaps the RD-0110 for the more efficient RD-0124 and delivers markedly greater performance. The vehicle can fly as a three-stage rocket for low Earth orbit or add a fourth stage — most commonly the Fregat or Fregat-M tug, with the smaller Volga as a cheaper option — to reach higher orbits. It is active and flies from Baikonur, Plesetsk and, since 2016, Vostochny, carrying payloads such as Progress MS cargo ships, crewed Soyuz MS spacecraft, and weather and remote-sensing satellites.

• 2004

  Soyuz 2.1a/Fregat-M

  "Soyuz 2.1a/Fregat-M" does not denote a stand-alone rocket but a specific stack: the baseline Soyuz-2.1a model of the Russian Soyuz-2 family, topped by the optional Fregat-M upper stage. Soyuz-2 is a series of expendable medium-lift launch vehicles built by the Progress Rocket Space Centre (RKTs Progress) in Samara, and is the seventh major iteration of the Soyuz family, itself descended from the R-7. At 46.3 metres tall, 10.3 metres across at its widest and 312 tonnes at lift-off, the vehicle has the same overall dimensions in any of its variants. Soyuz-2.1a was the model that introduced the family's digital flight control system, replacing the analogue electronics of earlier Soyuz rockets. The new avionics were lighter, allowed in-flight trajectory adjustment and supported larger fairings. Its third stage retains the RD-0110 engine of the classic Soyuz, but with enlarged propellant tanks and a revised structure shared with the 2.1b. From Baikonur it places roughly 7,430 kilograms into low Earth orbit. The Fregat-M stage, built by NPO Lavochkin, is what turns the three-stage launcher into a four-stage vehicle able to reach high orbits or interplanetary trajectories. It stands 1.945 metres tall and 3.8 metres in diameter, weighs 7,640 kilograms fuelled, burns hypergolic dinitrogen tetroxide and UDMH through an S5.92 engine, and can restart up to seven times, letting it drop several payloads into different orbits during a single mission.

• 2006

  Soyuz 2.1b

  Soyuz-2.1b is the higher-performance variant of the Russian Soyuz-2 family, and therefore not a separate rocket but a configuration: it shares with the baseline 2.1a its airframe, its four strap-on boosters, its core stage and all of its digital avionics, differing only in the third stage. Where the 2.1a retains the veteran RD-0110 engine, the 2.1b fits the RD-0124, which uses an oxygen-rich staged combustion cycle. The change matters more than it sounds. Specific impulse rises from 326 to 359 seconds and, although maximum thrust drops slightly from 298 to 294 kN, the longer burn time on the same propellant load improves overall performance. In payload terms, capacity to low Earth orbit from Baikonur goes from roughly 7,430 kilograms for the 2.1a to 8,670 kilograms for the 2.1b; from Vostochny the comparison is 7,460 against 8,600 kilograms. Like the rest of the family it is 46.3 metres tall, 10.3 metres across at its widest and 312 tonnes at lift-off, and it is built by the Progress Rocket Space Centre in Samara. In its basic form it is a three-stage launcher, but it accepts an optional fourth stage — Fregat, or the cheaper Volga — for high-orbit missions; with Fregat from Baikonur it can send 2,350 kilograms towards a trans-lunar injection.

• 2026

  Soyuz 2.1b/Volga

  Soyuz 2.1b/Volga is not a distinct rocket but a specific configuration: a Soyuz-2.1b launch vehicle fitted with the Volga upper stage. Soyuz-2 is the Russian series of expendable medium-lift launch vehicles and the seventh major iteration of the Soyuz family, produced by the Progress Rocket Space Centre in Samara, with improved engines and a digital flight control system that enables launches from fixed platforms and supports larger payload fairings. Within that series, the 2.1b variant differs from the 2.1a in its third stage: it replaces the RD-0110 engine with the RD-0124, an oxygen-rich staged-combustion design that raises specific impulse from 326 to 359 seconds. Maximum thrust drops slightly, from 298 to 294 kN, but the longer burn time with the same propellant load improves overall performance: from Baikonur, low Earth orbit capacity rises from about 7,430 kg for the 2.1a to 8,670 kg for the 2.1b. Volga is a Russian upper stage from RKTs Progress derived from the propulsion module of the Yantar satellite and closely related to the retired Ikar stage. It serves as a lighter, more cost-effective alternative to Fregat, the upper stage used on most Soyuz-2 missions: is particularly suited to Sun-synchronous orbits of around 850 km, and costs up to four times less than Fregat. In short, it is the combination meant to place medium payloads into high or multiple orbits without paying for a Fregat.

• 2026

  Soyuz-5

  Soyuz-5, also known as Irtysh and formerly codenamed Fenix in Russian and Sunkar in Kazakh, is a Russian medium-lift launch vehicle developed by RKTs Progress. It is intended to replace the Ukrainian-built Zenit and to serve as the basis for Yenisei, a future super heavy-lift launcher. It flew for the first time on 30 April 2026 from Site 45 at the Baikonur Cosmodrome — the former Zenit pad — operated in partnership with the government of Kazakhstan. The vehicle uses a kerolox propellant combination throughout. The first stage is powered by the four-chambered RD-171MV, the most powerful liquid-fuel engine in the world and a direct descendant of the RD-170 built for Energia; the second stage uses a single RD-0124MS. For high-energy missions an optional third stage can be fitted, either the Fregat-SBU or the Blok DM-SLB, the latter shared with the Angara A5. Its 4.1 m diameter tanks allow Proton tooling to be reused and, being wider than Zenit's 3.9 m, carry more propellant for the same height. The base retains a 3.68 m aft section so the rocket remains compatible with Zenit's pad and ground support infrastructure. Development also answered a Kazakh requirement: to move away from the highly toxic hypergolic propellants used by Proton.

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  Soyuz 2.1b/Fregat Sheet pending