International Space Station stabilizes after just-docked Russian module suddenly fires thrusters The International Space Station tilted 45 degrees today after Nauka, a just-docked Russian module, suddenly and unexpectedly fired its thrusters. The launch of Nauka, also known as the Multipurpose Laboratory Module, did not go smoothly. Engine troubles and dodgy docking sensors meant that the vehicle did not rendezvous with …
and no possibility fixing this problem with duck tape or a DAP-like caulking compound like the last one ("There's a hole in the hull of the Soyuz. There's a hole in the hull of the Soyuz. There's a hole, there's a hole (etc.)")
Someone needs to seriously re-think QA at the payload spacecraft manufacturing facility in Russia...
NOTE: Open to corrections.
The west are unable to match Russia's dominance in rocket technology and R&D and, if I remembered correctly, full-flow engines were THE engines Russia uses extensively to fling stuff to space.
The west uses a bank of strap-on boosters while Russia uses a single engine.
Space.com reported that the latest news conference stated:
"The space station automatically recognized that Nauka's thrusters were sending the orbiting laboratory askew and ordered the Zvezda module to fire its own thrusters to compensate, a process completed by the robotic Russian Progress 78 cargo ship, which is also docked to the space station.
After the station regained its proper position, Nauka's overseers in Russia began work to ensure the thrusters would not fire mistakenly again, according to NASA. That command was successfully implemented as the space station flew over command stations in Russia."
As we found out with Hubble, decades old hardware and software is not the easiest thing to fix.
https://www.space.com/nauka-module-thruster-fire-tilts-space-station
hindsight: once docked to the station, all vehicles and modules need a 100% way of disabling their thrusters to avoid this kind of thing in the future. De-fueling would be one way. If it needs to move, re-fuel it using station supplies after verifying that you have positive navi-guess-ion control.
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> "The crew is not in any danger, never was in any danger, and attitude control has been regained," NASA spokesperson Rob Navias said about 50 minutes after the thrusters briefly fired.
It might just be the quote clipping out the human bits of the text, but this is a supremely blasé statement.
Particularly given that:
"It's also said that Nauka is out of propellant following its "tug of war" with the ISS."
So what they're saying is they didn't actually regain control. Nauka simply ran out before the ISS. Had the ISS been low on propellant to start with they could have been screwed (I presume they never let it get that low between resupplies, but the point stands).
That seems entirely plausible to me, with the caveat that when Stuff Happens, usually it's only people who were really closely involved who know all the facts, and it can often be from the outside - you and me - things look very different to how they were.
It may be we really are marginally informed, and are getting it wrong; but this is not to say things were *better* than we think. They could perfectly well have been worse. It's only to say we can probably know we don't really know, which is also rather alarming - that's all tax payer money up there, and we're in the dark. I wonder how much more information will come out over time, and how true and complete it will be (not that we can really know).
with the caveat that when Stuff Happens, usually it's only people who were really closely involved who know all the facts
Back in the 80's I was a Navy nuclear reactor operator. The 3 Mile Island incident report was required reading. Details were in the report NOT in the public sphere of info, of course, which may or may not have been classified. However, it painted a different picture since the design of the control room clearly played a significant part, and not just "operator incompetence".
I also read the classified version of the SL-1 accident. Classified details in that report shed a lot of light onto the actual cause. I had read the unclassified version years before in college. Conclusions between the reports are likely to differ by quite a LOT, in particular any blame and/or corrective actions to prevent such a thing from ever happening again. (and there may still be reasons to keep the classified version classified, so use FOIA if you wanna see it, you might get lucky)
Anyway if those involved did their jobs, the details will be in the classified version of the report. What the public sees may be heavily redacted, or simply have missing details. Amazingly NASA still has (need for?) classified info. No surprise, really.
"The 3 Mile Island incident report was required reading."
John Kemeny was the chief investigator for this incident and he wrote a piece in the Dartmouth Magazine about it. He went into the investigation that the operators were covering up mistakes etc. On testimony, one of the operators stated that they were never trained on the particular scenario on the simulator.
Kemeny immediately requested access to the simulator and found that the scenario could not be simulated on the simulator. So the operators could not possibly have been trained for the incident as the simulator could not simulate it.
I believe it's the case that in the TMI safety calculations, they had assumed that the probability of two particular valves both being closed at the same time was the probability of A being closed multiplied by the probability of B being closed. But the instructions to the operators were to close valves A and B at the same time (before a test) and open them both at the same time (after the test). So, a completely bogus and very low fault probability was calculated, due to an elementary failure to understand when Bayes' Theorem applies.
Also I believe that the message warning that A and B were both closed (which buggered the reactor's cooling system) came out on the alarm printer several hours after the accident started, because such a low probability event was assigned a very low printing priority, and hundreds of other messages were melt-down warnings that got printed first.
So, yes, perhaps the operators screwed up, but the smarty-pants designers screwed up worse.
P.S. That was all in public reports.
"NASA and Boeing will hold off launching a cargo resupply mission, ... “Currently, launch teams are assessing the next available opportunity,”
The SciFi / this-is-outer-space aspects strongly return every so often. Why launch a resupply mission until you know the ISS will be there upon arrival?
Sail on good ship
The first mistake was having Nauka ABLE to fire thrusters before all systems had been checked out post-docking. That's like putting in a new pump motor with the power hot.
I'm wondering which Nauka thrusters were used: If the big ones, they may already be EOL (Nauka's dozen small thrusters have much longer lifetimes). The fact that Nauka used up all its fuel so quickly makes me suspect it was indeed the large thrusters that fired.
I hope the Russians (and EU?) are able to quickly send enough fuel for both Zveda and Nauka. SpaceX should be able to handle fuel needs for the rest of ISS. (I also don't know if Cargo Dragon can carry and transfer Russian fuel.)
Current situation aside, it would seem that Nauka received less that complete testing, particularly integration testing. Sorta reminds me of Boeing's Starliner. And the original Hubble mirror issue.
Space is extremely unforgiving of system integration mistakes, nearly all of which can be attributed to inadequate pre-/post-integration testing.
It was using them right up until it docked. It's supposed to shut them down then.
Clearly it didn't.
Best guess is that it never properly entered hard-dock mode and tried to "correct" an imagined attitude problem as its gyros drifted or similar.
On the way to the ISS they could not initially use the main engines because of gasses in the propellant lines. Fixing this was hindered by communications hardware problems and because they can only communicate when Nauka is over a ground station. By the time communications were re-established the tank pressure was too high to use the main engines and they had to use the smaller ones instead.
Overall, an excellent recovery by the operations team. They presciently used far more propellant than initially planned which proved useful when dealing with the unexpected thruster firing after docking.
I reckon that it might have been so out from what could be tested that it was likely dropped off some check list....
What was done was really amazing. They recovered a failed module, using the thrusters and managed to get it to the ISS something like 6 days late - imagine the out of profile working that was required to get it there..... Then a manual dock (likely with low fuel as it must have been mostly expended getting to the ISS).... then an error - which didnt destroy the ISS.
Pilots do say that 'A 'good' landing is one from which you can walk away. A 'great' landing is one after which they can use the plane again.'
Pints to the mission control tbh!
I also don't know if Cargo Dragon can carry and transfer Russian fuel
thrusters often use hydrazine, which acts like a liquid explosive under the right conditions.
One resource that flashed by in a search said there aren't any thrusters on the US side of the ISS and that they're on the Russia side. So if that is the case, fuel is probably compatible.
The Hubble telescope mirror error was interesting. The main mirror had to be finished to a fraction of a wavelength of light. They used a laser interferometer to measure the surface of the mirror. The problem was that one of the gauge blocks was off by .01". A knife edge check showed the error but, since the interferometer was far more accurate, they went with it.
You can't see a .01" error by eye so you have to trust your measuring tools.
Similar type of problem with the detection of neutrinos traveling faster than light - so many places for error.
Before laughing too hard it is remotely possible that one day Orion capsules will launch on SLS rockets. Perhaps some of the younger commentards here will still be alive if this happens and can recommend Roscosmos for their proven ability to recover from issues with antique space hardware.
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