Crew Dragon Lifeboat for Stranded ISS Crewmembers?

The safety of crew-members aboard the International Space Station (ISS) has been foremost on the minds of NASA and Roscosmos personnel after MS-22, a Russian Soyuz capsule docked to the ISS, sprung a coolant leak on 14 December 2022, thereby calling into question the craft’s spaceworthiness.

The leak lasted hours, disrupting station operations, and forcing cosmonauts Sergey Prokopyev and Dmitri Petelin to abandon a planned spacewalk. Russia's space agency, Roscosmos, posits the leak may be attributable to a micrometeoroid having punctured the capsule.

In addition to conveying crewmembers to the ISS, Soyuz capsules act as lifeboats in which station personnel may shelter or escape the orbital facility outright in the event of emergency. NASA astronaut Frank Rubio, along with the aforementioned Prokopyev and Petelin, traveled to the ISS aboard Soyuz MS-22 last year and were scheduled to return to Earth in March 2023 via the same capsule. NASA and Roscosmos have spent the last three-weeks investigating the coolant leak’s cause, assessing the damage to MS-22, and evaluating means by which to solve the conundrums inherent the loss of the Soyuz capsule and the redundancy it represented.   

NASA set forth in a statement that it has "reached out to SpaceX about its capability to return additional crew members aboard Dragon if needed in an emergency, although the primary focus is on understanding the post-leak capabilities of the Soyuz MS-22 spacecraft."

SpaceX has yet to respond to NASA’s inquiry.

SpaceX has launched a number of successful Crew Dragon missions to the ISS. Ergo, it is conceivable another such mission could be undertaken for purpose of fetching Rubio, Prokopyev, and Petelin safely back to Earth.

However, SpaceX custom makes space-suits for Dragon occupants—suits which differ drastically from the Russian Orlan and NASA’s EMU (Extravehicular Mobility Unit) suits currently aboard the ISS. Whether or not the latter suits are compatible with Dragon’s systems, or can even be fit into the SpaceX vessel’s seats, is unknown. What’s more, a SpaceX-facilitated rescue is apt to have an impact on future ISS missions and crew rotations—such as SpaceX’s Crew-6 mission, which is slated to launch in early 2023.

Using MS-22 as originally planned is another possible route forward—provided doing so is deemed safe. Contrariwise, Roscosmos could send up a replacement Soyuz spacecraft.

"NASA and Roscosmos are continuing to conduct a variety of engineering reviews and are consulting with other international partners about methods for safely bringing the Soyuz crew home for both normal and contingency scenarios," NASA’s statement concluded. The agencies, in any case, are expected to arrive at a decision by the end of January 2023.

FMI: www.nasa.gov