Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Scott Manley" channel.

@Greippi10 I think it would have been fine to build multiple copies in tents and sheds and then test multiple subs into failure to see the variation in the end results. Even SpaceX failed quite a bit hardware in process. However, they only built one Titan and simply assumed it's okay.
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@ColdWarSubSailor_- That's why I suggested doing multiple tests to failure to see amount of variation in the strength. If you see huge variation in test results, your trust to "final" part should be pretty low, too.
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Explaining Starlink orbit manouver as "half a year long mouse fart" is both hilarious and surprisingly accurate.
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16:22 The exposure of this photo is perfect! Maybe one day we can have equally accurate exposure for the video, too. That would make diagnosing problems like this much easier.
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The biggest issue for Chernobyl was that the EZ-5 button (called SCRAM in Western countries) was designed to work correctly in designed operation states. The most important was that the core must have minimum of 30 control rods inserted at all times. And of course, the team operating the reactor before the accident had fully pulled all but 6–8 rods from the reactor. This would have caused runaway situation even earlier but thanks to strong xenon poisoning, the reactor was able to stay in low power state until practically all xenon was burned away.
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I would guess this was partial failure of the gimbal mechanism and the computer tried its best to compensate but couldn't do it with the broken gimbal. It was also interesting that the self-destruct mechanism didn't trigger before the rocket already touched the surface of the ocean.
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10:30 I think this part should underlined more. The fact that the engines have enough power to rip through 9 cm bolts diretly upwards on full power gives pretty good understanding how strong the engines are.
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Luckily this mission didn't need full performance envelope of this hardware. Otherwise there wouldn't have been enough energy to complete the mission.
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1:41 It appears that when the booster tries to re-light the inner ring engines, one of the outer ring engines starts to glow (about 14 clock direction in the video). I would guess that was the initial cause for the booster failure.
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7:33 Great work spotting the increased usage of LOX!
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19:00 This is a perfect example of metaphorical truth: technically wrong but results in usable result. However, it would be really good idea to tell pilots that's only metaphorical truth so they don't go around thinking that's how things actually work.
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I'm not sure if you were serious or not but the problem with dumping stuff to Venus is that for every ton you want to get there, you need roughly 200 tons of fuel from Earth for the transportation. It get's kind of expensive pretty fast. And that assumes that the transport device is single use so you have to write the whole vehicle off for every trip, too.
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Is there even a reasonable plan to have something else but burst plates to act as valves? For this short demonstration shot replacing 3 plates per launch doesn't seem that bad but if the final product is supposed to have hundreds or thousands of boost stations, you cannot keep replacing burst plates for every launch or it will be more expensive than rockets very soon. Especially with SpaceX constantly lowering the price of getting 1 kg to orbit. Update: I see you asked this very same thing around 14:38 – great job! If they go with that plan, they will require a lot of machinery to be built before they can start shooting stuff but assuming that they can rebuild the burst plates in automated manner (or otherwise cheap enough) you're absolutely correct that in the long run the amount of consumables per launch is the most important thing and here it appears that the amount of hydrogen + energy needed to compress it + amount of energy needed to manufacture the burst plates might be less than what SpaceX can do. Of course, if SpaceX can get their launch even cheaper per kilogram, then it might cause problems for this project. Is there even a rough estimate how much it would cost to build all the machinery with the whole track? Are we talking about SpaceX budget already?
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The objective is to run Starlink satellites as close to Earth as possible to minimize the latency for the internet connection that the satellites provide down to Earth. However, the closer to Earth you go, the more friction you'll have from the upper atmosphere and the more active engine power you need to keep on the orbit. Even if SpaceX could easily take the satellites to 300 km above the Earth, they would probably not do that for Starlink satellites.
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@ColdWarSubSailor_- If you want to switch to radically different design (e.g. carbon fiber) the only way to make it safe is to figure out the amount of actual variance in your production methods. Because there will be always a lot of variables in real world processes, you cannot estimate this even close to perfectly and testing to failure is the only way to know for sure.
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2:05 I interpret the graphics for the booster that rapid disassembly was triggered when 8/13 engines had failed to re-light. I don't know what went wrong but obviously re-lighting the booster engines had success rate well below 50%. Considering that all the remaining engines were on one side of the booster, it probably couldn't have landed even if it hadn't exploded this soon.
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