Russia to Launch Replacement Soyuz, Bring Soyuz MS-22 Back Uncrewed

Russia’s space agency announced today that it will send up an empty Soyuz spacecraft to replace Soyuz MS-22 and bring home two Russian cosmonauts and an American astronaut later this year. They were supposed to come back on Soyuz MS-22 in March, but a coolant leak caused by a micrometeoroid strike left the spacecraft unsafe for human occupancy. Soyuz-23 will arrive in February. The crew will extend their stay on ISS, but for exactly how long is to be determined.

The U.S.-Russian-European-Canadian-Japanese International Space Station has been permanently occupied by international crews rotating on roughly 4-6 month schedules for the past 22 years.

Russian Soyuz spacecraft have ferried crews back and forth throughout that time and for many years was the only available transportation system. The basic Soyuz spacecraft dates back to the 1960s, although it has been upgraded several times.

These days Soyuz takes crews to and from ISS twice a year typically with mixed crews from Russia and the United States. Soyuz MS-22 launched in September with Roscosmos’s Sergei Prokopyev and Dmitri Petelin and NASA’s Frank Rubio.

On December 14 EST (December 15 UTC), just as Prokopyev and Petelin were about to exit the space station for a spacewalk, Soyuz MS-22, docked just outside, began leaking coolant into space. The cosmonauts remained inside the airlock and eventually the spacewalk was cancelled.

All the coolant escaped meaning thermal conditions inside the spacecraft cannot be maintained. Not only would that pose danger for crew members, but equipment like computers could be affected by overheating and high humidity.

Today, Roscosmos announced that it will replace Soyuz MS-22 with a new spacecraft.

Joel Montalbano, NASA’s ISS program manager, was in Moscow to participate in the meetings. He and Sergei Krikalev, Roscosmos’s Executive Director for Human Space Flight Programs and a former cosmonaut, briefed the media via telecon this morning. Roscosmos and NASA have been working closely together to determine the path forward.

The plan is to launch Soyuz MS-23 with no one aboard on February 20. It will dock with the ISS and over the next week or two equipment such as seat liners and spacesuits, which are individually fitted to each crew member, will be transferred from Soyuz MS-22 to Soyuz MS-23. Sometime in mid-late March, Soyuz MS-22 will undock and return to Earth empty. Although it cannot carry crew, Roscosmos expects it will function adequately to be recovered nominally.

Soyuz MS-23 was intended to bring Russian cosmonauts Oleg Kononenko and Nikolai Chub and NASA astronaut Loral O’Hara to ISS in March. Instead they will fly later in the year on Soyuz MS-24. Krikalev said no missions will be canceled, but all flights will shift to the right until they can get back on the original schedule.

Krikalev and Montalbano are convinced the hole in the Soyuz MS-22 radiator and the coolant loop was caused by a micrometeoid particle, not by space debris, based on imagery and the results of a hypervelocity test conducted on the ground by Roscosmos. Krikalev said they cannot repair the damage because it is in a difficult to reach location and even if they could fix the hole, they do not have replacement coolant. Asked if they plan any design changes to provide more protection for that area of Soyuz, he said they cannot add insulation because the radiator needs to be exposed to space to do its job and making the radiator thicker would add weight. Soyuz has two coolant pumps but only one coolant loop and an option they may consider is to add a second loop for redundancy, but that is also difficult.

Soyuz not only ferries crews back and forth, but serves as a lifeboat if there is an emergency on the ISS that requires evacuation. Krikalev said that in the unlikely event something like that happens between now and when Soyuz MS-23 arrives, they would have to weigh the risks of using Soyuz MS-22 despite the thermal problems or remaining on the space station.

Montalbano said NASA continues to talk with SpaceX about whether it would be possible for additional crew members to return to Earth on Crew Dragon Endurance, which delivered the four-person Crew-5 crew and will bring them home. No decisions have been made, but it might be possible in an emergency to move some equipment from Soyuz MS-22 to secure crew members in the area inside the Crew Dragon capsule usually used for cargo. NASA is not looking at making any changes to the next Crew Dragon that will launch Crew-6, only at the Crew-5 spacecraft.