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It's in many movies... the astronaut grabs a fire extinguisher and uses it to propel themselves around. It's even in the Shuttle operations manual (2.2-9)

"Consideration should be given to the propulsive force on the crewmember when discharging the extinguishers on orbit."

So, has anyone actually tried it for real? When the fire broke out on Mir I have seen some descriptions of one crewmember having to hold the legs of the other to prevent him from moving backwards. Are there more detail descriptions of this, or reports from other incidents (including training).

The Rocket fan
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Innovine
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  • This has me wondering how many lbf of thrust a fire extinguisher would give. I want to say it would be on par with a satellite's cold gas thruster's force rating? And if the astronaut is pushed against the surface of the spacecraft, then it seems a fire extinguisher would slightly alter its orientation, which would need correcting for by GNC? –  Feb 08 '21 at 15:24
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    I don't know, I've never discharged one, but think it's quite plausable that it'd set an astronaut tumbling violently. And get them moving, if aimed through their center of mass. – Innovine Feb 08 '21 at 15:45
  • @a1ex the gas impacting the other wall will cancel the motion out again, so the spaceship might move a little but stop again by itself. I was thinking more like an astronaut riding one around in a vacuum, or in a large container like skylab.. – Innovine Feb 08 '21 at 15:47
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    The only time I'm aware of handheld fire extinguishers being discharged in space was during the fire on Mir. The account in Dragonfly of this incident does not mention any problems with thrust from the extinguishers. That account states that Korzun discharged the extinguisher alone, with no one holding his legs. After using one extinguisher up, he returned to the base block and got a 2nd one from Kaleri. By the time he was on the 3rd one, Linenger had come in to help, but was asked to leave. – Organic Marble Feb 08 '21 at 17:31
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    On fire extinguisher - no. But cosmonauts on Salyut were flying on a vacuum cleaner. The greyfaces from NASA decided it's too much fun and so the vacuum cleaner on ISS has a special omnidirectional exhaust that makes it impossible. – SF. Feb 09 '21 at 06:37
  • @SF anti-NASA snark is often justified, but not in this case. Your comment is wrong. https://www.google.com/amp/s/www.cnet.com/google-amp/news/iss-space-station-cosmonaut-vacuum-cleaner-anton-shkaplerov/ – Organic Marble Feb 09 '21 at 14:07
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    @OrganicMarble Eh, it was more tongue-in-cheek. I'm well aware a runaway vacuum cleane can cause serious damage. – SF. Feb 09 '21 at 15:11
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    @Innovine Actually, that was one of the things that sort of ruined the movie The Martian for me. In the scene near the end when Mark uses propulsive cold gas to translate to his rescuer, he makes no effort to try to direct the thrust through his cg (er, I mean center of mass). A "real life" Mark would have known to do this, intuitively... – Digger Mar 08 '21 at 17:55
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    @digger I built a simulator in VR, with thrust coming from the hand controller position. It is impossible to direct yourself anywhere, you just get violent spins and a mostly random direction. True, there is no tactile feedback or inner ear feeling for acceleration, but the physics are good enough to convince me that it is difficult. I did not yet test two thrusters, to fly like iron man, but i cant imagine that being effective either. The tiniest little off-CG direction and you start to tumble. I suspect this is even worse than a single thruster – Innovine Mar 09 '21 at 11:11
  • @Innovine I can envision a quite feasible way Mark could have done what he did with that hand thruster, but won't elaborate here. Perhaps you could pose this problem as a question and I could answer - but please let me know as soon as said question is posted, as I don't get on here regularly... – Digger Mar 10 '21 at 16:26
  • @Digger Agreed! Though The Martian (both the book and movie) were actually soft realism, not hard realism, in the sense that there were serious problems scientifically with many of the aspects of Mark's stay on the surface (wind speed too high, dust inhalation would have surely killed him, etc, etc.). Still a very good book though.(: – AnarchoEngineer Jan 08 '23 at 22:40

2 Answers2

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If you look on YouTube (or various other places) you will have no problem seeing people using fire extinguishers to propel office chairs (and other devices). The physics in space is no different - you are basically talking about a rocket, indeed the difference between a water-based fire extinguisher and a water-bottle rocket is pretty trivial.

MikeB
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    The question is "So, has anyone actually tried it for real?" in space. – Organic Marble Feb 08 '21 at 21:46
  • I thought that the core question was "Is this effect for real?" Maybe I was wrong. – MikeB Feb 08 '21 at 21:52
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    There's only one sentence with a question mark in the question as asked, and it's "So, has anyone actually tried it for real?" – Anton Hengst Feb 08 '21 at 22:11
  • @AntonHengst But that was then immediately answered by the OP: "When the fire broke out on Mir ..." and then follows up by querying whether: "... one crewmember having to hold the legs of the other" – MikeB Feb 09 '21 at 07:08
  • There are conflicting reports about the incident on Mir, and little info on the actual extinguisher used. I am interested in other incidents, such as perhaps discharge of an extinguisher during a training exercise, which did not get much media attention. There is no doubt in my mind that some kind of propulsion is possible. I wrote a VR simulator which allowed me to spray a virtual extinguisher, and it only ever sent me spinning, it was impossible to use it as a means of controlled moving around (as you see in movies) – Innovine Feb 09 '21 at 16:33
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    Am I wrong in thinking that the quote from the Shuttle manual was intended as a warning, rather than a "How-To" ? – MikeB Feb 09 '21 at 20:41
  • One could argue that, actually, the physics in Space are different. In the posited case of "people using fire extinguishers to propel office chairs (and other devices)...", any moments generated by the propulsive force are nulled by the fact that said office chair is supported by at least three (presumably) wheels... – Digger Apr 11 '21 at 16:12
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I am pretty sure that it has never been tried recreationally or as a demo. An extinguisher would have to be brought to space just for that purpose, since there is no way they would use one meant for safety just for fun. And extinguishers tend to be messy. I don't know what kind they use in space, but again I am doubtful they would discharge one unless it was truly necessary.

I've read a lot about Skylab over the years, and I am confident I would have heard of it if they had done it on that station. It is the sort of thing that would make a popular video if it had ever been done on Mir or the ISS either, so that is more reason to doubt that it ever has.

I didn't see any article that gave more detail about how they used the extinguishers on Mir.

Mark Foskey
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  • not an extinguisher, but... https://space.stackexchange.com/a/30712/12102 (scroll to end) – uhoh Feb 09 '21 at 05:56
  • References are needed. This is a vague 'I think' kind of answer. More info about the Mir fire is readily available. – Organic Marble Feb 09 '21 at 14:08
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    Was it ever tested on a vomit comet? It strikes me as strange that some important piece of safety equipment like this would not have been tested at some point. In addition to propulsive forces, there must be questions about the dispersal patterns and how the cabin oxygen gets stirred up when using an extinguisher, as well as where the enxtinguisher contents end up. It's a pretty complicated flow of chemicals onto a very dangerous fire... not like NASA to just have a guess at what might happen and leave it at that.. – Innovine Mar 09 '21 at 11:14