# Soyuz 25 > crewed flight of the Soyuz programme **Wikidata**: [Q846547](https://www.wikidata.org/wiki/Q846547) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Soyuz_25) **Source**: https://4ort.xyz/entity/soyuz-25 ## Summary Soyuz 25 was a crewed flight of the Soviet Union's Soyuz programme, launched on October 9, 1977. It carried cosmonauts Vladimir Kovalyonok and Valery Ryumin aboard a Soyuz 7K-T spacecraft. The mission completed 32 orbits of low Earth orbit before landing on October 11, 1977, in Kazakhstan. ## Key Facts - Soyuz 25 was a crewed flight of the Soyuz programme, operated by the Soviet space program. - It launched on October 9, 1977, from Baikonur Cosmodrome, specifically from Gagarin's Start. - The mission utilized a Soyuz 7K-T spacecraft and was launched by a Soyuz-U rocket. - The crew consisted of Vladimir Kovalyonok (spacecraft commander) and Valery Ryumin (Flight Engineer 1). - Soyuz 25 completed 32 orbits and had an orbital period of 88.66 minutes. - Its takeoff mass was 6860 kilograms. - The flight duration was 175485 seconds, landing on October 11, 1977, in Kazakhstan. - The mission's call sign was Фотон (Foton). - It was preceded by Soyuz 24 and followed by Soyuz 26. ## FAQs ### Q: What was the purpose of the Soyuz 25 mission? A: Soyuz 25 was a crewed flight as part of the Soviet Union's Soyuz programme. It involved a launch, orbital operations, and a landing with a crew, contributing to the ongoing human spaceflight efforts of the Soviet space program. ### Q: Who were the crew members of Soyuz 25? A: The primary crew members of Soyuz 25 were Vladimir Kovalyonok, who served as the spacecraft commander, and Valery Ryumin, who was the Flight Engineer 1. ### Q: When did Soyuz 25 launch and land? A: Soyuz 25 launched on October 9, 1977, from Baikonur Cosmodrome. It landed two days later on October 11, 1977, in Kazakhstan. ### Q: What type of spacecraft and launch vehicle did Soyuz 25 use? A: Soyuz 25 used a Soyuz 7K-T spacecraft, which is part of the second generation of Soyuz spacecraft. It was launched into orbit by a Soyuz-U rocket. ## Why It Matters Soyuz 25 was a key component of the Soviet Union's ongoing Soyuz programme, representing a continued commitment to human spaceflight in the late 1970s. As a crewed mission, it contributed to the operational experience and development of space travel technologies, utilizing the Soyuz 7K-T spacecraft and a Soyuz-U launch vehicle. The mission's data, including its launch from Baikonur Cosmodrome, orbital parameters, and crew composition, provides valuable historical context for understanding the capabilities and procedures of the Soviet space program. Its place in the sequence of Soyuz missions, following Soyuz 24 and preceding Soyuz 26, highlights the continuous nature of Soviet space exploration efforts and the iterative process of spacecraft development and mission planning by its manufacturer, S.P. Korolev Rocket and Space Corporation Energia. This mission, like others in the program, was instrumental in advancing the Soviet Union's expertise in orbital mechanics, crewed operations, and re-entry procedures. ## Notable For - Being a specific crewed flight (SCN 10401) within the Soviet Union's Soyuz programme. - Carrying cosmonauts Vladimir Kovalyonok (commander) and Valery Ryumin (Flight Engineer 1). - Utilizing the Soyuz 7K-T spacecraft, a second-generation Soyuz design, and a Soyuz-U launch vehicle. - Completing 32 orbits of low Earth orbit with an orbital period of 88.66 minutes. - Its launch from Gagarin's Start at Baikonur Cosmodrome on October 9, 1977, and landing in Kazakhstan on October 11, 1977. ## Body ### Overview Soyuz 25 was a crewed spaceflight conducted by the Soviet Union as part of its Soyuz programme. It was designated with the SCN 10401 and COSPAR ID 1977-099A. The mission was operated by the Soviet space program and manufactured by S.P. Korolev Rocket and Space Corporation Energia. The mission's native label was Союз-25. ### Spacecraft and Launch Vehicle The mission utilized a Soyuz 7K-T spacecraft, which is classified as a second-generation Soyuz spacecraft. The launch vehicle for Soyuz 25 was a Soyuz-U rocket, a variant known as Universal. The spacecraft's takeoff mass was 6860 kilograms. ### Crew The primary crew for Soyuz 25 consisted of: - Vladimir Kovalyonok, serving as the spacecraft commander. - Valery Ryumin, serving as Flight Engineer 1. The backup or reserve team included Yury Romanenko as spacecraft commander and Aleksandr Ivanchenkov as Flight Engineer 1. The mission's call sign was Фотон (Foton). ### Mission Timeline and Operations Soyuz 25 launched on October 9, 1977, from the Baikonur Cosmodrome, specifically from the launch pad known as Gagarin's Start. This launch was a significant event in the mission's timeline. The spacecraft entered low Earth orbit with an orbital inclination of 51.64 degrees. Its orbital parameters included an apoapsis of 258.1 kilometers and a periapsis of 198.5 kilometers, both relative to Earth. The orbital period was 88.66 minutes. The mission completed 32 orbits around Earth. The total duration of the flight was 175485 seconds. ### Landing The landing of Soyuz 25 occurred on October 11, 1977, in Kazakhstan. This event marked the conclusion of the mission. The time of object orbit decay was recorded as 1977. ### Context and Relationships Soyuz 25 followed the Soyuz 24 mission and was succeeded by Soyuz 26, placing it within a continuous series of crewed flights in the Soyuz programme. The mission's logo is associated with the Salyut program insignia. ## References 1. Jonathan's Space Report 2. Freebase Data Dumps. 2013 3. [Source](http://www.spacefacts.de/mission/english/soyuz-25.htm)