Kathy Lueders (Deputy NASA Director for Human Spaceflight Operations) says that so far ISS cooperation between NASA and Roscosmos is "nominal". But NASA is "monitoring the situation". So far they still plan for NASA ISS astronaut Mark Vander Hide to return to Earth on a Soyuz as originally planned.
https://twitter.com/SciGuySpace/status/1...4319890442
But former Shuttle Program Manager Wayne Hale told the NASA Advisory Committee that NASA should consider creating a "Tiger Team" to prepare contingency plans for the ISS.
Vander Hide losing his Russian ride wouldn't be a huge problem since an upcoming Crew Dragon could launch with an empty seat for him. It would require preparing a SpaceX spacesuit for him (since only SpaceX suits work on the Crew Dragons since the capsule supplies air, cooling, comms and stuff through an umbilical) and it would probably mean extending his time on the station for months due to the capsule rotation schedules.
If the Russians plan to disconnect their modules and leave in a huff, that might doom the station because each side of the station relies on services like power (provided by the American side) and life-support (provided by the Russian side).
https://twitter.com/cbs_spacenews/status...7850715141
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