Soyuz-2

The Soyuz-2 project was initiated in the early 1990s by RKTs Progress with support from the Government of Russia as the "Rus" program. Following the Dissolution of the Soviet Union, it aimed to consolidate production within Russia and replace foreign-supplied systems while modernizing the aging Soyuz-U and Molniya-M launch vehicles. These earlier rockets relied on 1960s-era analog guidance systems developed by the Ukrainian Polisvit Special Design Bureau. Soyuz-2 introduced a fully digital flight control system and upgraded engines. Development of the digital system began in 1993 at NPO Avtomatiki in Yekaterinburg, incorporating triple redundancy and dual gyroscopes to improve reliability. The modernization program also included updated RD-107A and RD-108A engines for the boosters and core stage, as well as the development of the new RD-0124 third-stage engine employing oxygen-rich staged combustion. Together, these upgrades were intended to increase payload capacity by approximately . Financial constraints in the late 1990s led to a phased implementation of upgrades. The improved RD-107A and RD-108A engines were completed before the other planned improvements and entered service first on the transitional Soyuz-FG, while most structural and avionics changes were introduced later with Soyuz-2.1a. The new RD-0124 engine was later introduced with Soyuz-2.1b. == Variants ==

Soyuz-2.1a Soyuz2.1a introduced the digital flight control system, replacing the analog unit used on previous Soyuz rockets. The vehicle uses upgraded RD-107A and RD-108A engines, featuring over 1,000 single-component injectors replacing earlier dual-component designs, improving combustion efficiency and increasing specific impulse by approximately . The first Soyuz2.1a launch took place on 8 November 2004 from Plesetsk Cosmodrome Site 43 with a boilerplate payload simulating a Zenit-8 reconnaissance satellite. The first Soyuz2.1b launch occurred on 26 July 2008 from Plesetsk Cosmodrome Site 43 with a classified military payload. File:Expedition 72 Launch (NHQ202409110009).jpg|Closeup of booster and core stage engines of a Soyuz2.1a during launch File:Expedition 72 Soyuz Rollout (NHQ202409080028).jpg|Soyuz2.1a prepared for Soyuz MS-26 File:Soyuz 2.1b GLONASS-K2 13L launch 04.jpg|Soyuz2.1b prepared for GLONASS-K2 satellite launch File:"Soyuz" launch vehicles model series on MAKS-2021.jpg|From left to right: Soyuz2.1v, Soyuz2.1b, Soyuz2.1a (crewed variant), and the proposed Soyuz5 == Vostochny modifications ==

The Soyuz-2 family received specific modifications for operation from the Vostochny Cosmodrome, aimed at improving reliability, compatibility with ground infrastructure, and safety: == Notable missions ==

Suborbital test flight On 8 November 2004, at 18:30 UTC, the first Soyuz2 rocket, in the Soyuz2.1a configuration, was launched from the Plesetsk Cosmodrome in Russia. The rocket followed a suborbital trajectory, with the third stage and Boilerplate landing in the Pacific Ocean. Maiden launch The first attempt at launching a Soyuz2 to orbit with the MetOp-A satellite occurred on 17 July 2006. It was scrubbed two hours before the launch by an automatic sequence after the onboard computer failed to check the launch azimuth. Fuelling of the rocket was underway at the time, and all launch complex equipment and onboard preliminary checks had proceeded without incident. The rocket was left fuelled on the launch pad for the next attempt on 18 July 2006. Launch was eventually conducted on 19 October 2006. First crewed mission The first crewed launch of Soyuz2 took place on 9 April 2020, carrying Soyuz MS-16 to the ISS. Naphthyl fuel Following successful ground testing, a naphthyl (Russian: нафтил) fueled Soyuz2.1b launch took place on 22 October 2022 at Vostochny. Naphthyl is an environmentally safe hydrocarbon fuel with fewer aromatic compounds than kerosene, which also slightly improves engine performance. There are only minor differences in thermal properties, viscosity, and surface tension, so this did not require significant engine changes. == Launch statistics ==

Since 2006, Soyuz2 rockets have accumulated a total of 165 launches, 160 of which were successful, yielding a success rate. For Soyuz flights for ESA/Ariannespace from French Guiana see Soyuz-ST. Launch outcomes Launch sites == List of launches ==

Planned launches == See also ==