Soyuz 31 (, ''Union 31'') was a 1978

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

crewed space flight to the

Salyut 6 Salyut 6 () was a Soviet orbital space station, the eighth station of the Salyut programme, and alternatively known DOS-5 as it was the fifth of the Durable Orbital Station series of civilian space stations. It was launched on 29 September 19 ...

space station A space station (or orbital station) is a spacecraft which remains orbital spaceflight, in orbit and human spaceflight, hosts humans for extended periods of time. It therefore is an artificial satellite featuring space habitat (facility), habitat ...

. It was the seventh mission to and sixth successful docking at the orbiting facility. The Soyuz 31 crew were the second to visit the long-duration

Soyuz 29 Soyuz 29 (, ''Union 29'') was a 1978 crewed Soviet space mission to the Salyut 6 space station. It was the fifth mission, the fourth successful docking, and the second long-duration crew for the orbiting station. Commander Vladimir Kovalyonok an ...

resident crew. Soyuz 31 carried

Valery Bykovsky Valery Fyodorovich Bykovsky (; 2 August 1934 – 27 March 2019) was a Soviet cosmonaut who flew on three space flights: Vostok 5, Soyuz 22, and Soyuz 31. He was also backup for Vostok 3 and Soyuz 37. Early life and career Born in Pavlovs ...

and

Sigmund Jähn Sigmund Werner Paul Jähn (; 13 February 1937 – 21 September 2019) was a German Aircraft pilot, pilot, cosmonaut, and ''Generalmajor#Generalmajor in East Germany, Generalmajor'' (equivalent to a Brigadier General in Western armies) in the Nat ...

, the first

German German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also Ge ...

cosmonaut An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a List of human spaceflight programs, human spaceflight program to serve as a commander or crew member of a spa ...

, into space. They swapped Soyuz craft with the long-duration crew and returned to Earth in Soyuz 29, the resident crew returned to Earth in Soyuz 31.

Crew

Backup crew

Mission parameters

*Mass: *Perigee: *Apogee: *Inclination: 51.64° *Period: 88.81 minutes

Mission highlights

Soyuz 31, the third

Intercosmos Interkosmos () was a Soviet space program, designed to help the Soviet Union's allies with crewed and uncrewed space missions. The program was formed in April 1967 in Moscow. All members of the program from USSR were given the Hero of the Sov ...

flight, was launched 26 August 1978. Cosmonauts Bykovsky and Jähn were greeted by resident crew

Vladimir Kovalyonok Vladimir Vasiliyevich Kovalyonok (; ; born 3 March 1942) is a retired Soviet Union, Soviet cosmonaut. He entered the Soviet space programme on July 5, 1967, and was commander of three missions. Together with Aleksandr Ivanchenkov he flew the lo ...

and

Aleksandr Ivanchenkov Aleksandr Sergeyevich Ivanchenkov (; born 28 September 1940) is a retired Soviet cosmonaut who flew as Flight Engineer on Soyuz 29 and Soyuz T-6, he spent 147 days, 12 hours and 37 minutes in space. Ivanchenkov first flew on Soyuz 29 in 1978 ...

when they docked at the aft port of the Salyut 6 space station the next day. The visitors brought with them fresh onions, garlic, lemons, apples and other food for the long-duration crew, then in space for more than two months. The presence of the East German cosmonaut was seen as significant because of the presence of the MKF-6M camera on the space station, built by the Carl Zeiss works at

Jena Jena (; ) is a List of cities and towns in Germany, city in Germany and the second largest city in Thuringia. Together with the nearby cities of Erfurt and Weimar, it forms the central metropolitan area of Thuringia with approximately 500,000 in ...

. Medical and biological experiments were carried out, including an audio experiment which tested sound and noise perception limits. An experiment called Berolina used the Splav furnace to process an

ampoule An ampoule (also ampul and ampule) is a small sealed vial which is used to contain and preserve a sample, usually a solid or liquid. Ampoules are usually made of glass. Modern ampoules are most commonly used to contain pharmaceuticals and chem ...

bismuth Bismuth is a chemical element; it has symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs nat ...

and

antimonide Antimonides (sometimes called stibnides or stibinides) are compounds of antimony with more electropositive elements. The antimonide ion is but the term refers also to any anionic derivative of antimony. Antimonides are often prepared by heating ...

with the material between two plates in the ampoule. The tree structure which resulted was four to six times larger than what had been produced on the ground. Another experiment tested using different photographic films on the station's interior. The Soyuz 31 crew swapped craft with the Soyuz 29 crew so as to supply the long-duration crew with a fresh craft. On September 2, the engines of Soyuz 29 were tested, 25 experiment containers with 100 experimental results were transferred, along with exposed film, and seat liners and centering weights were exchanged. The Soyuz 31 crew left in Soyuz 29 the next day and landed 140 km southeast of

Dzhezkazgan Zhezkazgan, or Jezkazgan ( ) is a city and the administrative centre of Ulytau Region, Kazakhstan. Population: Its urban area includes the neighbouring mining town of Satpayev, for a total city population of 148,700. 55% of Jezkazgan's popu ...

. The standard recovery procedure was changed with this flight, observers noted. In the past, the recovery of a civilian Salyut crew had been made on the orbit following the one which provided a nominal launch opportunity to Salyut. With this and subsequent flights, the landing occurred during the orbit which provided the nominal launch opportunity. The effect of this change was to have a landing window open some two to three days earlier than otherwise. The crew on the station subsequently boarded the Soyuz 31 vehicle and redocked it to the forward port, thus freeing the aft port for a forthcoming

Progress Progress is movement towards a perceived refined, improved, or otherwise desired state. It is central to the philosophy of progressivism, which interprets progress as the set of advancements in technology, science, and social organization effic ...

supply ship. They returned to Earth 2 November in the craft after setting a new space-endurance record of 139 days.

References

{{Orbital launches in 1978 Crewed Soyuz missions 1978 in the Soviet Union East Germany–Soviet Union relations 1978 in East Germany Spacecraft launched in 1978 Spacecraft which reentered in 1978 Spacecraft launched by Soyuz-U rockets