Today’s failed Soyuz launch thankfully resulted in no casualties, but the fate of the International Space Station (ISS) is now in question.
Just two minutes after liftoff, the crew of the Soyuz MS-10 found themselves in a situation that every astronaut since the beginning of the manned space program has trained for, but very few have ever had to face: a failure during launch. Today the crew of two, Russian Aleksey Ovchinin and American Nick Hague, were forced to make a ballistic re-entry into the Earth’s atmosphere; a wild ride that put them through higher G forces than expected and dropped the vehicle approximately 430 km from the launch site in Baikonur. Both men walked away from the event unharmed, but while the ordeal is over for them, it’s just beginning for the crew of the ISS.
Until a full investigation can be completed by Roscosmos, Russia’s space agency, the Soyuz rocket is grounded. This is standard procedure, as they obviously don’t want to launch another rocket and risk encountering the same issue. But as the Soyuz is currently the only way we have to get humans into space, this means new crew can’t be sent to the ISS until Roscosmos is confident the issue has been identified and resolved.
Soyuz MS-11, which would have brought up three new crew members to relieve those already on the Station, was scheduled for liftoff on December 20th. While not yet officially confirmed, that mission is almost certainly not going to be launching as scheduled. Two months is simply not long enough to conduct an investigation into such a major event when human lives are on the line.
The failure of Soyuz MS-10 has started a domino effect which will deprive the ISS of the five crew members which were scheduled to be aboard by the end of 2018. To make matters worse, the three current crew members must return to Earth before the end of the year as well. NASA and Roscosmos will now need to make an unprecedented decision which could lead to abandoning the International Space Station; the first time it would be left unmanned since the Expedition 1 mission arrived in November 2000.
An Expiring Ticket
ISS crews are rotated out on a six month schedule because that’s about how long a Soyuz capsule can remain viable in orbit. It has a design life of only 215 days, any longer than that and the vehicle’s corrosive propellants will degrade their tanks. Current ISS crew members Sergey Prokopyev, Alexander Gerst, and Serena M. Auñón-Chancellor arrived at the station in June on Soyuz MS-09, so the clock has nearly run out for their spacecraft.
If Soyuz MS-09 is left attached to the Station past its design life, it will become unusable. In the worst case, it could even start leaking propellant and endanger the Station. The crew would be forced to cut the spacecraft loose, leaving themselves stranded. This is an option that simply will not be considered by either NASA or Roscosmos. Under no circumstances will either agency intentionally leave three humans in space with no way to bring them home.
If nothing changes, the current crew will therefore be forced to depart before their only ride home literally eats itself. This would leave the Station unmanned until Soyuz can be flown again and bring a new crew. As there’s no telling when that might be, this would be a crushing blow to ISS operations. It could potentially start another domino effect of delaying future missions and experiments, such as the unmanned test flight of SpaceX’s new Dragon capsule which is currently slated to arrive at the Station in April.
Sending an Unmanned Lifeboat
There are a few potential alternatives to leaving the ISS without a crew for the first time in nearly 20 years, but given the risk-adverse nature of human spaceflight, it seems unlikely NASA or Roscosmos will want to tempt fate on any of them. If this were a Hollywood film, we might see the President order SpaceX to rush around the clock to finish their new Dragon capsule in time to perform a daring rescue, but in reality it simply isn’t worth the risk to human life. The ISS will survive this mishap, even if it means putting a pause on the program for a few months.
There is however at least one contingency plan which has historic precedent. Roscosmos could attempt to launch the Soyuz MS-11 spacecraft on December 20th as originally planned, but without the crew. If the booster fails again, at worst they will have only lost the hardware and no human life. But if it survives the trip into space, it could be remotely guided to the ISS, and serve as the crew’s new return vehicle. This would allow them to remain aboard the Station for another six months, hopefully enough time to complete the accident investigation and resume normal launches.
This is precisely what happened in 1979 aboard the Salyut 6 space station. When Soyuz 33 suffered an engine failure before docking with the orbiting outpost, it not only deprived the Salyut 6 crew of additional members, but called into question the reliability of their own identical spacecraft. No longer sure they had a safe return vehicle, the crew was forced to remain in orbit until the remotely controlled Soyuz 34 could be sent to the station as a lifeboat. The crew left Salyut 6 aboard Soyuz 34 after commanding their original spacecraft to re-enter the atmosphere by remote control. Ultimately both spacecraft landed safely, with no human or material loss.
While it was never needed, a similar contingency plan was put into place after the loss of Space Shuttle Columbia. It would have allowed the crew of a damaged Shuttle to remain on the ISS until a new Shuttle could be sent up to get them. Their original Shuttle would then attempt an unmanned landing under remote control in an effort to save the expensive reusable spacecraft with no risk to its human occupants.
It’s exceptionally difficult to believe Roscosmos could rush through an incident investigation before the scheduled December 20th launch of Soyuz MS-11, even if the fault is found to be operational and not with the rocket itself. When the unmanned Proton-M rocket was lost in 2013 due to an improperly installed angular velocity sensor, it still look three months for the investigation to clear the rocket for its next flight. Even if the Russian government was content with a truncated investigation, Soyuz MS-11 will have an American and Canadian aboard, so NASA and CSA would surely want time to review the findings themselves.
If the International Space Station is evacuated, it will break the continuous human presence in space we’ve maintained since the dawn of the 21st century. If on the other hand a solution can be devised which allows the Station to remained crewed, it will be the kind of last-minute engineering and international collaboration we rarely see outside of science fiction. No matter what happens next, we’ll be watching history be made.