The NASA and Russian federal space agency, Roscosmos, have been at odds regarding the future of the PrK tunnel, a section connecting the Russian Zvezda module to an aft docking port.
Since 2019, the tunnel has been leaking air, reaching a rate of two pounds of air per day during recent cargo operations. On June 5, 2019 disagreement between NASA and Roscosmos over repair methods reached a breaking point.
The Russian space agency is planning to use drastic measures, such as a handsaw and a drill to modify the module. NASA opposed this plan to saw off a load-bearing bracket in the PrK module, fearing it could cause a “bad outcome” or structural failure.
As a result, the US-based space agency has directed four SpaceX Crew-12 astronauts and NASA astronaut Chris Williams to take a safe haven position inside their docked Dragon capsule due to concerns over Roscosmos’ risky repair attempts.
According to one NASA official, “We threatened we would put astronauts in suits, in Dragon, to send a message to the world that we disagreed. They didn’t care.”
Instead of attempting the risky repairs, NASA emphasized on a collaborative approach as such methods, including cutting the brackets could damage the integrity of nearby stations.
On the other hand, Roscosmos offered a different perspective, maintaining that the situation is under control. As per the agency, one leak has been plugged and the second one is under repair and it does not pose any damage to the crew and nearby station systems.
Another proposed solution has been offered related to permanently shutting and sealing the PrK tunnel.
While this would stop the specific leak, it is not a permanent structural fix and would limit future docking capabilities.
Moreover, the closure of the PrK would also affect the station’s ability to reboost and complicate logistics. The leak also highlights the urgency of moving from the ISS to commercial space stations. According to the GAO report, NASA must decide by 2027 whether to extend the ISS beyond 2030 and use private alternatives.