A Russian cargo spacecraft docked to the International Space Station suffered a coolant leak today, the second in as many months. In December, the Soyuz MS-22 crew spacecraft lost all of its coolant. Engineers concluded it likely was due to a micrometeorite strike, but now that Progress MS-21 seems to have a similar leak, they will have to look even more closely at the data to ensure there is no common defect that could affect other spacecraft. Soyuz MS-23, a replacement for Soyuz MS-22, is scheduled for launch next week.
NASA confirmed the coolant leak this afternoon, saying NASA specialists are helping troubleshoot the problem and the seven ISS crew members are in no danger.
The reason for the loss of coolant in the Progress 82 spacecraft is being investigated. The hatches between the Progress 82 and the station are open, and temperatures and pressures aboard the station are all normal. The crew, which was informed of the cooling loop leak, is in no danger and continuing with normal space station operations. — NASA
The incident takes place just two months after the Soyuz MS-22 crew spacecraft dramatically spewed coolant into space just as two Russian cosmonauts were about to exit the nearby airlock to conduct a spacewalk. The December 14, 2022 EST leak was caused by a hole in the spacecraft’s coolant loop. Based on imagery analysis and a hypervelocity test conducted on the ground, Roscosmos and NASA believe the hole was created by a micrometeorite impact.
Soyuz MS-22 delivered Russian cosmonauts Sergey Propokyev and Dmitry Petelin and NASA’s Frank Rubio to ISS in September and was supposed to bring them home in March. All the coolant was expelled so once the spacecraft departs the ISS the interior temperature cannot be maintained properly. Roscosmos does not want to use it to bring the crew home unless there’s an emergency and instead is launching an empty replacement, Soyuz MS-23, next week. The crew that was supposed to fly to ISS on Soyuz MS-23 (two Russians and an American) will have to wait for Soyuz MS-24.
Having both a Soyuz and a Progress experience coolant leaks at all is quite surprising, never mind in such a short period of time. While it may be coincidental, the possibility of a common design or manufacturing defect will have to be investigated.
Soyuz and Progress spacecraft have been launched for decades. They have very similar designs with Soyuz capable of carrying crews and Progress dedicated to cargo. The first Progress was launched in 1978 to resupply the Soviet Salyut 6 space station. They delivered cargo to that space station and its successors, Salyut 7 and Mir, and now to ISS.
The spacecraft has been upgraded several times. The current version is Progress MS. On Thursday, Russia launched Progress MS-22. It successfully docked at the ISS this morning. NASA numbers Progress missions starting with the first to resupply the ISS in 2000. Its name for Progress MS-22 is “Progress 83” or “83P,” because it is the 83rd Progress to dock at ISS.
At least one Progress is usually docked at the ISS and often two. Progress MS-22 is replacing Progress MS-20 (81P), which just left on February 8, and Progress MS-21 (82P), which is scheduled to undock on February 17.
Just hours after Progress MS-22’s arrival, however, Russia’s space agency Roscosmos posted on Telegram that Progress MS-21 had depressurized. It’s been docked to the ISS since October 28, 2022.
Russian space enthusiast Katya Pavlushchenko who closely tracks the Russian space program and follows Roscosmos on Telegram broke the news on Twitter.
1. There is a leak in the external radiator cooling loop of #ProgressMS21.
2. The hatch to the ship has been immediately closed.
3. The crew is in no danger.
4. RSC Energia calls a meeting to decide what to do next.
5. The launch of Soyuz MS-23 will be postponed.
— Katya Pavlushchenko (@katlinegrey) February 11, 2023
Later, Sergei Krikalev, the head of human spaceflight at Roscosmos and one of Russia’s most experienced cosmonauts, posted on Telegram that specialists are investigating what happened and will have to “rule out that this is not a systematic [sic] error because it can affect the following ships,” but so far no changes have been made to the ISS program.
Сергей Крикалев рассказал о ситуации с «Прогрессом МС-21» на МКС
Сегодня на грузовом корабле, который уже несколько месяцев пристыкован к станции, произошла утечка теплоносителя из системы терморегулирования.
По словам Сергея Крикалева, в настоящее время специалисты думают над тем, как детально осмотреть место утечки на радиаторе «Прогресса МС-21», чтобы выяснить причину ее появления. Необходимо убедиться, что это не систематическая ошибка, потому что она может повлиять на следующие корабли.
Пока ситуация с «Прогрессом МС-21» не привела к изменению программы полета МКС.
[As translated by Google Translate]
Sergey Krikalev spoke about the situation with “Progress МС-21” on МКС
Today, on a cargo ship that has been docked at the station for several months, there has been a coolant leak from the thermoregulatory system.
According to Sergei Krikalev, at the present time specialists are thinking about how to examine in detail the place of the leak on the radiator “Progressa MC-21” in order to find out the reason for its appearance. It is necessary to make sure that this is not a systematic error, because it can affect the following ships.
So far the situation with the “Progress МС-21” has not led to a change in the MKS flight program.
Soyuz MS-23, the empty replacement for Soyuz MS-22, is scheduled for launch on February 19 EST, so near-term decisions are needed on whether to proceed. Russia moved the launch date for Soyuz MS-23 up by several weeks to get it there as soon as possible since Soyuz MS-22 is compromised.
Soyuz spacecraft not only ferry crews to and from ISS, but are safe havens if orbital debris, for example, threatens the ISS as it did after Russia conducted an antisatellite test in November 2021, and lifeboats if the ISS must be evacuated for any reason such as a fire or depressurization.
In the unlikely event an evacuation is needed before Soyuz MS-23 arrives, Roscosmos and NASA have a contingency plan in which Prokopyev and Petelin would take their chances in Soyuz MS-22 and Rubio would move in with Crew-5 in Crew Dragon. The reasoning is that with only two instead of three people in Soyuz, the thermal load might be manageable, albeit uncomfortable. Crew Dragon actually was designed to accommodate seven people and there are only four in Crew-5, so there’s plenty of room and consumables for Rubio, even if there is no seat for him. His customized seat cushion was moved from Soyuz into Crew Dragon and secured in an area otherwise used for cargo.
Notes: Pavlushchenko refers to February 18 as the date for Progress MS-21’s deorbiting because it will be February 18 in Russia. It is February 17 UTC. The translation of Krikalev’s comments refers to Progress MC-21 because the letter “C” in cyrillic is “S” in English and Google Translate missed that one. “MKS” are the cyrillic letters for International Space Station: Международная космическая станция.