Progress 7K-TG
Progress 7K-TG was a Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 unmanned spacecraft used to resupply space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...

s in low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

. Forty three flew, delivering cargo to Salyut 6
Salyut 6
Salyut 6 , DOS-5, was a Soviet orbital space station, the eighth flown as part of the Salyut programme. Launched on 29 September 1977 by a Proton rocket, the station was the first of the 'second-generation' type of space station. Salyut 6 possessed several revolutionary advances over the earlier...

, Salyut 7
Salyut 7
Salyut 7 was a space station in low Earth orbit from April 1982 to February 1991. It was first manned in May 1982 with two crew via Soyuz T-5, and last visited in June 1986, by Soyuz T-15. Various crew and modules were used over its lifetime, including a total of 12 manned and 15 unmanned launches...

, and Mir
Mir was a space station operated in low Earth orbit from 1986 to 2001, at first by the Soviet Union and then by Russia. Assembled in orbit from 1986 to 1996, Mir was the first modular space station and had a greater mass than that of any previous spacecraft, holding the record for the...

. It was the first version of the Progress spacecraft to fly, and spawned later derivatives including the Progress-M
Progress-M , 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, originally built in the late 1980s as a modernised version of the Progress 7K-TG spacecraft, using new systems developed for...

 which replaced it, and the later Progress-M1
Progress-M1 , also known as Progress 7K-TGM1, is a Russian spacecraft which is used to resupply space stations. It is a variant of the Progress spacecraft, derived from the Progress-M, but modified to carry more propellent for refuelling the space station instead of other cargoes such as water...


The Progress 7K-TG spacecraft was derived from the manned Soyuz 7K-T
Soyuz 7K-T
The second generation of the Soyuz spacecraft, the Soyuz Ferry or Soyuz 7K-T, comprised Soyuz 12 through Soyuz 40 . Although still using the Igla system, these had no solar panels, employing batteries...

 "ferry" spacecraft, which
had been designed for the Salyut programme. 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, 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
Progress 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 configuration. It carried supplies for the EO-1 crew aboard Salyut 6, which consisted of...

, was launched on 20 January 1978. The first twelve spacecraft flew to Salyut 6, with the next thirteen, including the Kosmos 1669
Kosmos 1669
Kosmos-1669 was a Progress spacecraft used to resupply the Salyut 7 space station. It was a Progress 7K-TG spacecraft with the serial number 126....

 spacecraft - a Progress spacecraft which was given a Kosmos
Cosmos (satellite)
Kosmos is a designation given to a large number of satellites operated by the Soviet Union and subsequently Russia. Kosmos 1, the first spacecraft to be given a Kosmos designation, was launched on March 16, 1962....

 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 is an improved version of the original Soyuz LV. Soyuz-U is 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 constructed at the Progress Factory in Samara, Russia....

 carrier rockets. Progress 20 and all of the Mir flights used the more powerful Soyuz-U2
The Soyuz-U2 was a Soviet, later Russian, carrier rocket. It was derived from the Soyuz-U, and a member of the R-7 family of rockets...

 carrier rocket. The last spacecraft, Progress 42, was launched on 5 May 1990. It was deorbited on 27 May, breaking up in the atmosphere over the Pacific Ocean at around 12:27 GMT.

Some Progress 7K-TG launches used the payload fairing developed for the Soyuz spacecraft, including the escape tower
Escape tower
An Escape Tower, the original version officially known as the Aerial Capsule Emergency Separation Device, is the visible part of the Launch Escape System. It consists of a rocket and a frame attaching it to the top of the crew capsule...

, 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 under development for the Buran programme. In addition to their regular cargoes, the Progress 7 spacecraft was used to transport the KRT-10 radio telescope
Radio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...

 to Salyut 6, and Progress 17 delivered the Iskra 3 satellite to Salyut 7 for deployment.

See also

  • Automated Transfer Vehicle
    Automated Transfer Vehicle
    The Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency . ATVs are designed to supply the International Space Station with propellant, water, air, payload and experiments...

  • Cygnus spacecraft
    Cygnus spacecraft
    The Cygnus spacecraft is an unmanned resupply spacecraft being developed by Orbital Sciences Corporation and Thales Alenia Space as part of NASA's COTS project. It is designed to transport supplies to the International Space Station after the retirement of the Space Shuttle...

  • H-II Transfer Vehicle
    H-II Transfer Vehicle
    The H-II Transfer Vehicle , called , is an unmanned resupply spacecraft used to resupply the Kibō Japanese Experiment Module and the International Space Station . The Japan Aerospace Exploration Agency has been working on the design since the early 1990s. The first mission, HTV-1, was originally...

  • Soyuz programme
    Soyuz programme
    The Soyuz programme is a human spaceflight programme that was initiated by the Soviet Union in the early 1960s, originally part of a Moon landing project intended to put a Soviet cosmonaut on the Moon...

  • SpaceX Dragon
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.