NASA and Roscosmos disagree on the causes and severity of the air leak on the Zvezda module. According to NASA, it could lead to a “catastrophic failure” of part of the Russian segment of the ISS.
The disagreement was revealed during a brief meeting of NASA’s ISS Advisory Committee on November 13. It outlines the meeting of this committee with Roscosmos representatives in Moscow in September.
A leak in the Zvezda module was discovered in September 2019. It is located in the transition chamber that separates the docking port from the rest of the module. The crews on the station deal with it by shutting it off when they don’t need access to the Progress cargo spacecraft docked to Zvezda.
Russian engineers believe the cracks are likely caused by high cyclic fatigue from micro-vibrations. In contrast, NASA is of the opinion that several factors came into play, including pressure and mechanical stress, residual stress, module material properties, and environmental effects. NASA’s Office of Inspector General (OIG) stated in a September report that the two organizations focused their attention on internal and external welds in search of the leak.
At a September 27 briefing, NASA officials downplayed concerns about the leak, which had grown to a record 1.7 kilograms of air per day by early this year. Then they said recent maintenance work had reduced that rate by a third.
Nevertheless, the leak remains a concern for both NASA and the space station crews. Astronaut Michael Barratt, who recently returned to Earth, admitted that every time the hatch to the transition compartment is open, astronauts close the transition between the Russian and American segments of the ISS.
However, NASA and Roscosmos don’t agree on the severity of the problem. At the September meeting, NASA expressed concern about the structural integrity of the transition chamber and the potential for catastrophic failure. Roscosmos denies the possibility of such a scenario.
To better understand the causes of the situation on the ISS, NASA attracted an independent group of engineers to analyze the problem. However, given Roscosmos’ official position on the severity of the situation, there is no guarantee that the organization will heed its conclusions.
Earlier we covered how SpaceX practiced destroying the ISS.
Provided by Spacenews
