(russianspaceweb.com)
Site 31 for the Soyuz rocket family
in Baikonur
The second launch facility for the R-7-based launch vehicles at Site 31 in Tyuratam was built in the 1950s but it received an official designation 17P32-6, or Pad No. 6 for short, in the 1980s, years after four more pads for the same rocket family were introduced in Plesetsk. Soon thereafter, the Tyuratam test range itself became Baikonur Cosmodrome.
Previous chapter: Site 2
History of Site 31 and 32
At the end of 1958, a year-and-half after the R-7 ballistic missile had began flying, the second launch complex for the same rocket was founded at Site 31, east of the original launch facilities in Tyuratam. Unlike the test launch complex at Site 1 and 2, the Site 31 facility was planned as an operational and training "battle station" for the R-7 missile. The new complex included the launch pad (Facility 353), the MIK assembly building (sometimes referred to as TP-2 from the Russian Tekhnicheskaya Pozitsiya 2), the MIK GCh building for the processing of the nuclear warhead, disel-powered energy generating facility and the new residential complex at Site 32.
Based on experience gained during the construction at Site 1 and 2, the flame trench at Site 31 launch pad was scaled down in comparison to that of at Site 1. The assembly and support facilities were also placed much closer to the launch pad.
The complex was completed at the end of 1960. On Feb. 27, 1961, the first R-7 ICBM lifted off from Site 31.
As the R-7's role as a carrier of the nuclear weapons had diminished, Site 31 along with Site 1 was re-purposed for orbital launches, including missions with cosmonauts onboard. The facility could be used for access to orbits with four different inclinations toward the Equator.
By the end of 1966, the fueling station designated 11G12 started operations providing fueling for piloted spacecraft, satellites and planetary spacecraft. The original Soyuz 7K-OK spacecraft and the 7K-L1 circumlunar vehicles were prepared for launch at the processing building at Site 31. However, on December 14, 1966, an on-pad explosion of a launch vehicle with the 7K-OK No. 1 spacecraft, which cost three lives, required urgent repairs at the facility.
On Jan. 14, 1969, Soyuz-4 was launched from Site 31, followed by Soyuz-6 on October 11, Soyuz 8 on October 13 and Soyuz-9 on June 1, 1970.
The first unpiloted Soyuz 7K-TM variant was launched from Site 31 on April 3, 1974.
Another wave of piloted launches started in 1980 with the launch of Soyuz-36 on May 26 and Soyuz-39 on March 22, 1981.
Yet another group of piloted launches came in the wake of the 1983 launch failure, which damaged a primary piloted launch pad at Site 1. Soyuz T-10 was launched from here on Feb. 8, 1984, followed by Soyuz T-11 on April 3 and Soyuz T-12 on July 17, 1984. As of 2006, out of 100 Russian piloted launches, a total of 12 lifted off from Site 31, according to Roskosmos.
According to the Russian press, during 2005, the launch complex and the processing facilities at Site 31 was being refurbished for the Soyuz-2 rocket.
Crew missions return to Site 31
In 2009, to support the anticipated increase of the International Space Station crew from three to six, Russia had to double piloted launches from two to four annually. The number of Progress cargo supply missions was to increase as well. As a result, various upgrades were conducted at Site 31 during 2007 and 2008, to enable piloted launches from both Site 1 and Site 31, Kazakhstan Today reported, quoting Baikonur officials.
Upgrades covered the fueling system and the flight control bunker. Also, a new air-conditioning system for the payload section of the rocket, a clean room and communications cables were installed.
At the time, the first launch of the Progress spacecraft from Site 31 was expected in 2008 and the first piloted Soyuz (since 1984) would blast off from the same pad in 2009. In reality, the first cargo ship, Progress M-66, lifted off from Site 31 on Feb. 10, 2009. Progress M-07M and Progress M-15M were also launched from the same pad on Sept. 10, 2010, and April 20, 2012, respectively.
In April 2011, the head of Roskosmos, Anatoly Perminov, said that Site 31 would be ready for piloted launches by the end of that year. Manned launches did resume from Site 31 on October 23, 2012, when Soyuz TMA-06M lifted off.
Moving both -- piloted and cargo launches -- to Site 31 would enable Roskosmos to start planned refurbishment of the launch pad at Site 1, which apparently was planned to start around 2014.
Upgrades for Fregat-SB
During 2009, a processing building at Site 31 -- MIK 40 -- was upgraded with a new work place for handling the Fregat-SB upper stage, which would be used with the Zenit-3M (Zenit-2SLB) rocket.
On Dec. 28, 2011, during the launch of the Soyuz-2.1a rocket with a cluster of Globalstar-2 satellites, Pad No. 6 at Site 31 sustained some damage. Strong winter winds pushed the fiery exhaust from the rocket into the service gantry, causing its deformation and preventing proper rotation of the structure into the operational position around the launch vehicle. Repairs at the pad were expected to last until the end of February - beginning of March 2012. (553)
400th rocket lifts off from Site 31
Progress MS-13 lifts off from Site 31 on Dec. 6, 2019.
Completing Russian missions to the International Space Station, ISS, in 2019 and for the 2010s, the Soyuz-2-1a rocket lifted off from Baikonur on December 6, 2019, successfully sending the Progress MS-13 cargo ship on a three-day trek to the outpost. Counting 14 suborbital launches from Site 31, it was the 397th liftoff in the history of the facility. Then, on April 9, 2020, the first crew-carrying Soyuz-2-1a variant with the Soyuz MS-16 spacecraft lifted off from Site 31, marking the 400th launch from the facility, according to some accounts.
A Soyuz rocket without a payload is installed on the launch pad at Site 31 on Dec. 19, 2022.
In August 2022, Semikhatov NPO Avotomatiki announced that a new domestically developed system for pre-launch diagnostics of launch vehicles would be installed on the launch facility, following just completed removal of the obsolete hardware. The new equipment was delivered to Baikonur in September 2022 and, from December 19 to December 22 of the same year, a Soyuz-2-1a vehicle intended for the launch of the Porgress MS-22 spacecraft was on Pad 6 for integrated tests of the just installed hardware but without fueling of the vehicle.
Site 31 in Baikonur circa 2025.
Russia's only pad for crew launches suffers major damage
The debris from the fallen service platform are visible at the bottom of the flame trench at Site 31 shortly after the launch of Soyuz MS-28 on Nov. 27, 2025.
According to multiple Russian sources, on Nov. 27, 2025, the launch of the Soyuz MS-28 crew vehicle caused the mobile service platform at Site 31 to collapse into the flame duct below the pad around 10 seconds after liftoff. It essentially rendered the only facility for Russian orbital crew launches unusable. At the time, Roskosmos planned the launch of the Progress MS-33 cargo ship to the ISS on Dec. 21, 2025, which was immediately cancelled.
According to preliminary estimates, repairs of the service platform, known as 8U0216, could take up to two years and it was not immediately clear whether some kind of makeshift arrangement would be possible to support multiple cargo and crew launches to the ISS in the interim. There was a possibility that some necessary hardware could be borrowed from the mothballed Site 1 in Baikonur or from similar facilities at other launch sites. There were four Soyuz pads in Plesetsk, including an unused existing structure at Site 16, also one pad operated in Vostochny and one mothballed pad was in Kourou, French Guiana. (The launch complex in French Guiana was specifically configured for the Soyuz-2 rocket family also operating from Site 31 in Baikonur.)
Soyuz pad damage caused by known issue
The failure to install a special stopper into position to secure the mobile service platform inside its shelter during the launch could be the culprit in the Nov. 27, 2025, accident at Site 31.
A veteran of the Baikonur Cosmodrome with good contacts at the center reported on the Novosti Kosmonavtiki web forum that the mobile platform had not been properly secured in its underground shelter before launch, which let the blast wave from the rocket exhaust pull it off its guide rails and into the flame trench. However, the collapse clearly took place some moments after the liftoff, because photos of the launch capturing the flame duct showed no signs of the failure.
According to one rumor from Baikonur, the mobile platform was retracted and moved back to the rocket as many times as five times, as the specialists tried unsuccessfully to secure it in its parking position inside its shelter, after the routine call to retract the platform had been issued during the final countdown less than an hour before launch.
When the personnel was finally ordered to evacuate the pad some 30 minutes ahead of the liftoff, the decision was made to leave the platform in its parking position inside its shelter without securing it properly rather then to postpone the launch. It was not immediately clear who made a decision to proceed with the launch despite this clear violation of launch criteria.
The veterans of the center speculated that the mission management had been under pressure to go ahead with the launch so not to disappoint high-ranking officials and as many as 3,000 paid tourists who came to the remote center to witness the event.
Several hours after the accident, Roskosmos issued a statement admitting damage "to a number of elements in the launch table" and the "the ongoing assessment of the launch complex condition." The press release also said that all the back-up elements necessary for the repair of the pad were available and that the damage would be fixed in "the nearest time." At the same time, available photos of the site showed that the entire mobile platform had collapsed and was clearly damaged beyond repair.
According to posters on the Novosti Kosmonavtiki forum, components of a spare mobile service platform, ordered by the Soviet government back in 1971, were delivered from the NKMZ factory in Ukraine to Baikonur in 2013. However, it likely represented the older 8U216 version of the structure and, in any case, its installation would require major construction work at the pad, including the dismantling of existing equipment. There was also a spare mobile platform stored at the arsenal of Space Forces in the town of Znamenka in the Tambov Region.
According to unofficial reports, Roskosmos planned to restore the launch pad at Site 31 by the Cosmonautics Day on April 12, 2026. The first deliveries of spare parts to Site 31 were rumored at the end of the first week of December 2025.
The repair plan apparently included the delivery of new mobile platform sections to the top deck of the launch structure (known as "Zero marker") along the usual rollout path for the Soyuz rockets and then lowering them with a crane via the circular opening of the pad for final assembly at the operational position of the mobile platform below the pad.
On Dec. 16, 2025, Roskosmos promised to have Site 31 ready for launches by the end of Winter 2026. According to the State Corporation, 18 heavy trucks had arrived to Baikonur with components for the restoration of the mobile platform, which were temporarily stored at a facility with a total area of more than 13 thousand square meters. A team of more than 130 Roskosmos employees, operating in two shifts from 8 a.m until midnight, were involved in the repair work under a newly approved and strictly controlled schedule.
The work started with priming and painting the components, after which they would be delivered to the pad for installation, Roskosmos said.
Next chapter: Energia launch facility in Baikonur
This page is maintained by Anatoly Zak; last update: December 17, 2025
Page editor: Alain Chabot; last edit: November 28, December 18, 2025
All rights reserved
The R-7 ballistic missile on the launch pad at Site 31 in Baikonur circa 1960. Copyright: RussianSpaceWeb.com
Soyuz-4 lifts off from Site 31 on Jan. 14, 1969.
The upper composite with a pair of Cluster spacecraft inside MIK 32 assembly building in July 2000. Copyright © 2000 Anatoly Zak
The Soyuz rocket during the processing inside MIK 32 assembly building. Click to enlarge. Copyright © 2000 Anatoly Zak
The housing and support complex at Site 32. Copyright © 2001 Anatoly Zak
The Soyuz-2-1a rocket with the Metop spacecraft on the launch pad at Site 31 in Baikonur on July 14, 2006. Credit: Roskosmos
The Soyuz-FG rocket is being installed on the launch pad at Site 31 in Baikonur on Oct. 18, 2007. Credit: Roskosmos
Progress M-66 lifts off from Site 31 in Baikonur on Feb. 10, 2009. Credit: Roskosmos
The Progress M-07M cargo ship at Site 31 shortly before launch on Sept. 10, 2010. Credit: TsENKI
The Soyuz U rocket rolls out from the assembly building at Site 32 two days before the launch of Progress M-15M cargo ship on April 20, 2012. Credit: RKK Energia
View of Site 31 shortly before launch of Foton-M4 satellite on July 19, 2014. Click to enlarge. Credit: Roskosmos
Soyuz-2-1a rocket prepares to launch Progress MS-14 spacecraft from Site 31 on April 25, 2020. Click to enlarge. Credit: Roskosmos
A Soyuz-2-1a rocket during tests of the new ground equipment at Site 31 in December 2022. Click to enlarge. Credit: Roskosmos
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Multiple views of the crashed service platform emerged immediately after the launch of the Soyuz MS-28 spacecraft from Site 31 on Nov. 27, 2025. Click to enlarge.
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Components of the mobile service platform during preparation for repairs of Site 31 in December 2025. Click to enlarge.
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A photo of repairs at Site 31 released on Dec. 16, 2025. Click to enlarge.
Spare electric motors to be used for the rotation of the mobile service platform as they were being readied for delivery to Site 31 in December 2026. Click to enlarge.