Tag: air leak

Russian astronauts locate another leak on Zvezda

8:44 am

According to Russia’s state-run TASS press, Russian astronauts have located what it calls “the last air leak” on the Zvezda module of ISS.

Russian cosmonauts Anton Shkaplerov and Pyotr Dubrov discovered the last air leak location in the International Space Station’s Zvezda module, Roscosmos spokesman Dmitry Strugovets said Tuesday, adding that the leak will be eliminated after special equipment is delivered to the station.

Like most of the other leaks previously found, this one was located in the aft transition chamber where the Zvezda docking port is located, once again suggesting that these leaks are the result of stress fractures caused by age and the more than a hundred dockings that have occurred there since Zvezda was launched more than twenty years ago.

The Russians’ belief that no more leaks will be found is probably based on their decision to reduce, even cease the use of this port. The new Prichal docking hub, which two Russians today are doing a spacewalk to finalize its integration with the station, makes the shuttering of Zvezda’s port possible.

At the same time, the existence of numerous stress fractures in an ISS module is not something to be dismissed lightly, as the TASS article attempts to do. It is akin to cracks in the hull of a submarine, and I don’t know anyone who would be willing to send such a vessel deep underwater.

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Russian astronaut id’s possible leak location in Zvezda

9:50 am

A Russian astronaut today told mission control that he thinks he has located another leak in the Zvezda module of ISS.

Roscosmos cosmonaut Pyotr Dubrov detected a possible air leak spot in the intermediate chamber of the Zvezda module aboard the International Space Station (ISS), the cosmonaut told the Flight Control Center during a communications session on Monday.

The Russian cosmonaut said he had traced the possible spot of the continued air leak while inspecting the Zvezda module’s intermediate chamber at the weekend. “I began preparing a perimeter for laying a cord today. I detected a suspicious spot and started to examine it,” the cosmonaut said, replying to a question about the work in the intermediate compartment in a live broadcast by NASA.

As the Russian cosmonaut said, he made a photo of the detected spot using a microscope with magnifying lens. He did not make video footage of the works, he said. [emphasis mine]

The highlighted words are significant. Up until now all leaks that the Russians have identified have been in Zvezda’s aft section, the part where the docking port is located. That pattern suggested that the many dockings over the module’s two decade-plus lifespan could have led to stress fractures in that module.

That they might have now found an air leak in intermediate section of the module suggests that the age-caused stress fractures are occurring in a more widespread manner. This is very concerning.

On a positive note, when the astronauts sealed the earlier leaks in the aft module, the loss of air dropped significantly. If the leak stops entirely when they seal this leak, we will have some confidence that the problem is under some control, for the time being.

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Due to cracks, Russia will no longer use Zvezda’s docking port

9:39 am

Russian officials today revealed that they will no longer use the docking port on its Zvezda module on ISS because of the stress fracture cracks they have found in the section where that port is located.

Russia is unable to use one of the docking ports of the ISS to its full extent due to cracks in the transitional chamber of the Zvezda module, the general designer of Russia’s Energia corporation, associate member of the Russian Academy of Sciences Vladimir Solovyov said on Monday. “The transitional chamber’s loss of airtightness is often mentioned these days. We are very fortunate the cracks are at the end. We shut down that compartment, thus losing one docking port, which narrows our opportunities somewhat. The crack is very insignificant, though,”

In other words, they have sealed the aft section of Zvezda to reduce further air leaks, thus also closing off access to the port.

The Russian portion of ISS presently has two docking ports on two different modules. When Roscosmos launches its Prichal docking hub in November, to be attached to Nauka’s port, they will then add four more ports.

This decision underlines the impending end to ISS’s life span. Zvezda is not the only old Russian module on ISS where stress fractures have been found. “In August they found cracks in the module Zarya, the oldest module on ISS.

Though the U.S. part of ISS shows no such problem, it is designed to rely on the Russian half for its operations. If Russia must shut down its modules then the station will not be able to function for much longer.

The U.S. will likely overcome some of these issues with the planned launch in ’24 of Axiom’s private commercial module to ISS, which will eventually evolve into an complete space station separate from ISS. For the Russians the pressure to design and launch their own new station has become more critical. Whether they can do it however is unknown. Russia has not built a new space station module in decades. Their new ISS module, Nauka, was built in the 1990s.

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Russians accuse American astronaut of drilling hole in Soyuz

10:41 am

In several articles published today in the state-run Russian press, the Russians made the accusation that the hole and drilling damage that had been found on an in-orbit Soyuz capsule was put there by an American astronaut.

The first link above notes that while the Russians took a lie detector test, showing they didn’t drill the hole, the Americans refused. A second TASS link argues that their investigation proves that all the drill damage had to been done in orbit, for two reasons. First, they always test the capsule’s intergrity in a vacuum chamber before launch, and would have discovered it then. Second, the nature of the drill damage suggests it was done in zero gravity.

A third link provides an English translation of the more detailed Russian report, which made this direct accusation:

Firstly, the illness of the female astronaut, which is the first known incident of deep vein thrombosis in orbit, and the fact that Serena Maria Auñón-Chancellor had suffered the condition was published in a scientific article only after she had returned to Earth. This could have provoked ‘an acute psychological crisis’, which could have led to attempts by various means to speed up her return to the planet, according to my anonymous source. Secondly, for some reason unknown to Roscosmos, the video camera at the junction of the Russian and American segments was not working at that time. Thirdly, the Americans refused to perform a polygraph examination, while the Russian cosmonauts were polygraphed. Fourthly, Russia never had an opportunity to study the tools and the drill which are aboard the ISS to see if there are any signs of metal shavings from the hull of our ship’s orbital module.

This longer article also makes the claim that, because of the location of some of the drill attempts, whoever did drilling had no knowledge of the Soyuz’s construction.

All this may be true, but it conveniently ignores several very important facts: The one successful drillhole that caused the leak had been patched, which would have prevented any leak during the vacuum tests on the ground. The leak occurred because the patch was not designed to survive the hostile environment of space and eventually failed.

Also, the Russians’ own investigation had found that there was plenty of time on the ground for this sabotage to have occurred, so saying it had to have happened in space is incorrect.

Finally, the claim that the drill damage had to have been done in zero gravity is pure opinion, and hardly evidence.

In other words, it sounds as if the Russians are trying to shift blame from themselves (and an unknown ground worker) to an American astronaut. It is certainly possible that their claims are true, but they seem incredibly implausible. Much more likely would be sabotage on the ground by a very disgruntled Russian worker, routinely underpaid and resentful of the corruption that permeates Roscosmos and all of Russian society.

Such a conclusion however would be beyond embarrassing for the Putin government and the head of Roscosmos, Dmitry Rogozin. It is far better to place the blame on an American, especially because the end of the U.S.-Russian partnership on ISS is only a few years away.

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Air leak in Russian section of ISS continues

8:27 am

Dmitri Rogozon, the head of Roscosmos, yesterday announced that they will be sending to ISS special equipment for investigating a new air leak in the Russia section of ISS.

This apparently is not the 1-2 inch long crack in the Zvezda module that leaked previously and was found and sealed. Moreover, the article at the link admits that their astronauts found no sign of damage on the outside of Zvezda when they did a space walk in November, suggesting that this first leak was not caused by a micrometeorite hit.

All the known facts so far strongly suggest that the leaks are because of Zvezda’s 20-year-old age, and might be stress fractures caused by the three dozen or so dockings and undockings that have occurred there since its launch.

That the Russians are being so vague about the entire matter reinforces that conclusion. They have never released an image of the first leak, and provided no details about the equipment being sent to the station.

And if Zvezda is beginning to crack due to age, I am not sure what repairs they can do to stop it.

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ISS air leak still unlocated

9:04 am

The small air leak that was found on ISS a year ago has still not been located, despite a second weekend where the crew isolated themselves in one module and closed the hatches on all other modules so that ground engineers could track any air supply changes.

At a Sept. 28 briefing about the upcoming Northrop Grumman NG-14 Cygnus cargo mission to the station, a NASA official said that the weekend isolation in the Zvezda module failed to immediately locate the source of the leak. “As of this morning, there was no clear indication of where the leak is,” said Greg Dorth, manager of the ISS Program External Integration Office at NASA. “The teams are still looking at the data and evaluating it.”

This was the second time the ISS crew confined themselves to Zvezda in an effort to track down the leak. A month earlier, the three also spent a weekend in Zvezda with the other modules sealed off in an effort to locate the leak. “After the three days, there was no indication of where the leak was coming from,” Dorth said.

This latest test, he said, featured some “slightly different configurations” in both the U.S. and Russian segments, although he did not elaborate on the differences between the two tests. In addition, Cassidy used an ultrasonic leak detector to see if the leak was coming from Zvezda itself.

These tests were possible since mid-August because there were only three people on station, allowing them to be confined to one module for a period of time. Moreover, during this time no other spacecraft have arrived or left. It is suspected that the leak is most likely coming from the connection point between two modules, and adding or removing a Soyuz, Dragon, or freighter to the station shifts its center of gravity, changing the stress points at those connections.

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