Houkago, Bokura wa Uchuu ni Madou - Ch. 2

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Interesting, it looks like their oxidizer is nitrous oxide, but I can't tell what their solid fuel is. Common hybrid solid fuels are not described as "resin". It is possible they are using HTPB.
ABS Resin is the solid fuel part. Acrylic resins are also used sometimes.
And yes, Nitrous Oxide is the oxidizer. That's right, their rocket is powered by legos and laughing gas.
 
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Oh, new work from Sautou-sensei. God I love this style
...is it alright if I'm not interested in main pair at all? Can I have a series about Tsuchiya?
 
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ABS Resin is the solid fuel part. Acrylic resins are also used sometimes.
And yes, Nitrous Oxide is the oxidizer. That's right, their rocket is powered by legos and laughing gas.
They are referred to as polymers, not resin. That being said, it is not known how they are casting the grains or if they are buying it from another shop. They do have a 3D printer so it is possible they are using ABS as the fuel. Utah State University is doing some experiment with 3D printed hybrids at a much smaller scale. If they have an PI hope they get an earful from campus safety officers.
 
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Interesting, it looks like their oxidizer is nitrous oxide, but I can't tell what their solid fuel is. Common hybrid solid fuels are not described as "resin". It is possible they are using HTPB. We can see they have at least two other casing/nozzle ready and have students design some part of the casing, which indicates that this club have access to a machine shop or have enough funding to get these things machined. Unfortunately it seems that they cheapened out on the test stand. A well design test stand should not have allowed the engine to come off the stand like a boomerang. It looks like a blowback failure or a burn through which could have killed someone if they got unlucky.
it looks like they had a full-sized gas tank of nitrous oxide behind (in front of?) the rocket, meaning they probably weren't going to use all the oxidiser they had available, but rather planned on just turning off the valve once the solid fuel has finished burning (hopefully automatically rather than manually, as nitrous oxide is both a pollutant and hazardous to health at amounts larger than the ones they give you at the dentist's, so you want as little of it as possible escaping).
what most likely happened is, as you said, a blowback or burn-through failure (though the motor looked fairly intact as it was flying out, so more likely the former) - but rather than just the remaining oxidiser for that specific run exploding, it was an entire tank of the stuff. i don't think that any test stand designed for the sort of rockets they're building - not even the most over-engineered one - is built to sustain forces that are both: 1) external in nature (from next to the stand rather than on it) and applied in the opposite direction than the one it's designed for 2) orders of magnitude larger than those produced by anything meant to be bolted to the stand.
luckily they appear to have followed proper test safety protocols, which were made specifically to keep people safe even in occasions such as these where something goes catastrophically wrong, so thankfully nobody was hurt.
 
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not to be weird but is it just me or its kiiiinnnndddaaa weird for a highschool freshmen to go viral international (her friend stated "world"so) just cuz shes "cute"
 
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it looks like they had a full-sized gas tank of nitrous oxide behind (in front of?) the rocket, meaning they probably weren't going to use all the oxidiser they had available, but rather planned on just turning off the valve once the solid fuel has finished burning (hopefully automatically rather than manually, as nitrous oxide is both a pollutant and hazardous to health at amounts larger than the ones they give you at the dentist's, so you want as little of it as possible escaping).
what most likely happened is, as you said, a blowback or burn-through failure (though the motor looked fairly intact as it was flying out, so more likely the former) - but rather than just the remaining oxidiser for that specific run exploding, it was an entire tank of the stuff. i don't think that any test stand designed for the sort of rockets they're building - not even the most over-engineered one - is built to sustain forces that are both: 1) external in nature (from next to the stand rather than on it) and applied in the opposite direction than the one it's designed for 2) orders of magnitude larger than those produced by anything meant to be bolted to the stand.
luckily they appear to have followed proper test safety protocols, which were made specifically to keep people safe even in occasions such as these where something goes catastrophically wrong, so thankfully nobody was hurt.
I mean, could be worse, they could be like Pythom Space:


The original unedited video showed the Pythom crew running away from an orange cloud of hypergolic exhaust...

u3gsia.jpg
 
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the failed rocket engine test gives me war flashbacks to my own engineering capstone project 5 years ago...

we also did a rocket engine for the school team
 
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Cute dork with great taste. Mars rovers cute. And new girl cute.
 
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In this comment section: literal rocket scientists musing about the “rocket” part of a manga using it as an excuse to have a cute girl doing cute things. :p

(To be clear, I’m not complaining, this is great! It also show that the mangaka probably did at least some research. XD )
 
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Sigh.

The doctor said that if I keep reading this he'll have to amputate both legs.

So, where's chapter 3?
 

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