Progress 7K-TG (russian: Прогресс 7К-ТГ, italic=yes,

GRAU index The Main Missile and Artillery Directorate of the Ministry of Defense of the Russian Federation (), commonly referred to by its transliterated Russian acronym GRAU (), is a department of the Russian Ministry of Defense. It is subordinate to the ...

11F615A15), was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

uncrewed spacecraft used to resupply

space station A space station is a spacecraft capable of supporting a human crew in orbit for an extended period of time, and is therefore a type of space habitat. It lacks major propulsion or landing systems. An orbital station or an orbital space station ...

s in

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never m ...

. Forty three flew, delivering cargo to

Salyut 6 Salyut 6 (russian: Салют-6; lit. Salute 6), DOS-5, was a Soviet orbital space station, the eighth station of the Salyut programme. It was launched on 29 September 1977 by a Proton rocket. Salyut 6 was the first space station to receiv ...

Salyut 7 Salyut 7 (russian: Салют-7; en, Salute 7) (a.k.a. DOS-6, short for Durable Orbital Station) was a space station in low Earth orbit from April 1982 to February 1991. It was first crewed in May 1982 with two crew via Soyuz T-5, and last v ...

, and

Mir ''Mir'' (russian: Мир, ; ) was a space station that operated in low Earth orbit from 1986 to 2001, operated by the Soviet Union and later by Russia. ''Mir'' was the first modular space station and was assembled in orbit from 1986 to&n ...

. It was the first version of the

Progress Progress is the movement towards a refined, improved, or otherwise desired state. In the context of progressivism, it refers to the proposition that advancements in technology, science, and social organization have resulted, and by extension w ...

spacecraft to fly, and spawned later derivatives including the

Progress-M Progress-M (russian: Прогресс-М, GRAU indices 11F615A55 and 11F615A60), also known as Progress 7K-TGM, is a Russian, previously Soviet spacecraft which is used to resupply space stations. It is a variant of the Progress spacecraft, or ...

which replaced it, and the later Progress-M1. Model of Salyut-7 with two Soyuz spacecrafts

The Progress 7K-TG spacecraft was derived from the crewed

Soyuz 7K-T The second generation of the Soyuz spacecraft, the ''Soyuz 7K-T'', comprised Soyuz 12 through Soyuz 40 (1973-1981). In the wake of the Soyuz 11 tragedy, the spacecraft was redesigned to accommodate two cosmonauts who would wear pressure ...

ferry spacecraft, which had been designed for the

Salyut programme The ''Salyut'' programme (russian: Салют, , meaning "salute" or "fireworks") was the first space station programme, undertaken by the Soviet Union. It involved a series of four crewed scientific research space stations and two crewed m ...

. The descent module of the Soyuz spacecraft was replaced with a new section designated ''Otsek Komponentov Dozapravki'', or OKD. This contained fuel tanks and pumps used for refuelling the space station that it docked with. Like the Soyuz 7K-T, the Progress was not equipped with

solar panels A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a phot ...

, and instead relied on batteries for power. Early spacecraft had a design life of 33 days, including three in free flight, and the rest docked with a space station. Later spacecraft flew longer missions, with the longest, Progress 38, spending almost 75 days in orbit. The first Progress 7K-TG spacecraft,

Progress 1 Progress 1 (Russian: ''Прогресс 1''), was a Soviet unmanned Progress cargo spacecraft which was launched in 1978 to resupply the Salyut 6 space station. It was the maiden flight of the Progress spacecraft, and used the Progress 7K-TG co ...

, was launched on 20 January 1978. The first twelve spacecraft flew to Salyut 6, with the next thirteen, including the

Kosmos 1669 Kosmos-1669 (russian: Космос-1669, italic=yes) was a Progress spacecraft used to resupply the Salyut 7 space station. It was a Progress 7K-TG spacecraft with the serial number 126. Mission Kosmos-1669 was launched by a Soyuz-U carrier ...

spacecraft - a Progress spacecraft which was given a

Kosmos The cosmos (, ) is another name for the Universe. Using the word ''cosmos'' implies viewing the universe as a complex and orderly system or entity. The cosmos, and understandings of the reasons for its existence and significance, are studied in ...

designation and omitted from the sequence of Progress designations - going to Salyut 7. The last eighteen flew to Mir. With the exception of Progress 20, all of the flights to Salyut stations were launched by

Soyuz-U The Soyuz-U launch vehicle was an improved version of the original Soyuz rocket. Soyuz-U was part of the R-7 family of rockets based on the R-7 Semyorka missile. Members of this rocket family were designed by the TsSKB design bureau and cons ...

carrier rockets. Progress 20 and all of the Mir flights used the more powerful

Soyuz-U2 The Soyuz-U2 (GRAU index 11A511U2) was a Soviet, later Russian, carrier rocket. It was derived from the Soyuz-U, and a member of the R-7 family of rockets. It featured increased performance compared with the baseline Soyuz-U, due to the use of ...

carrier rocket. The last spacecraft, Progress 42, was launched on 5 May 1990. It was deorbited on 27 May 1990, breaking up in the atmosphere over the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

at around 12:27 UTC. Some Progress 7K-TG launches used the payload fairing developed for the

Soyuz Soyuz is a transliteration of the Cyrillic text Союз ( Russian and Ukrainian, 'Union'). It can refer to any union, such as a trade union (''profsoyuz'') or the Union of Soviet Socialist Republics (Сою́з Сове́тских Социали� ...

spacecraft, including the launch escape tower, but with the motors in the tower removed, and no stabilisers on the sides of the fairing. Officially this was done to preserve the rocket's aerodynamic properties, however it was reported that on several flights the tower was used to support tests of the K-36M

ejection seat In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rocke ...

under development for the

Buran programme The ''Buran'' program (russian: Буран, , "Snowstorm", "Blizzard"), also known as the "VKK Space Orbiter program" (russian: ВКК «Воздушно-Космический Корабль», lit=Air and Space Ship), was a Soviet and later R ...

. In addition to their regular cargoes, the Progress 7 spacecraft was used to transport the KRT-10 radio telescope to Salyut 6, and Progress 17 delivered the

Iskra 3 ''Iskra'' ( rus, Искра, , ''the Spark'') was a political newspaper of Russian socialist emigrants established as the official organ of the Russian Social Democratic Labour Party (RSDLP). History Due to political repression under Tsar Ni ...

satellite to Salyut 7 for deployment.

References

{{DEFAULTSORT:7K-TG, Progress Progress (spacecraft)

See also

References