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New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

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Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#21

Post by lizardactivist »

cycrutchfield wrote: post #10
throwaway4good wrote: post #8

Earlier quoted context omitted.

It is a calculated risk; perhaps similar to what have been done by the US and Russia when their space ambitions were at their highest.

Ah, the good old “whatabout the US did it 50 years ago therefore we can do it today”. Also used to justify all sorts of atrocities, imperialism, IP theft, etc.

I think pulling the whataboutism card may have worked in the past, but today people realize it's just a really bad defense for when you have nothing sensible to reply with, after facts, inconvenient truths, and plain hypocrisy has been pointed out.

It's simply not the ace up the sleeve people think it is.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#22

Post by vasco »

k_paleologos wrote: post #16
throwaway4good wrote: post #13

Earlier quoted context omitted.

I also think there is a somewhat hyperbolic anti-China sentiment in the commentary on all of this. Plus a perhaps frustration at the US Space authorities on the lack of communication from their Chinese counterpart, something of course they themselves are entirely to blame for. Anyway; the Chinese have done a few of these "uncontrolled reentries" now. All crashing into the ocean; so they are either very lucky or it is…

Reports suggest that they require only 3 launches in this configuration LM5B where the core stage falls back, for the construction of their station. They might have made the assumption that chances of damage due to debris is very low considering that only 3 launches are to happen with this configuration. In case even if there is damage on the ground, there are treaties that govern the liabilities in case. It would be…

> In case even if there is damage on the ground, there are treaties that govern the liabilities in case.

If it fell on your house with you sleeping inside I'm sure the liabilities treaties would make your family be totally ok with it.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#23

Post by tjpnz »

throwaway4good wrote: post #8
Simon_O_Rourke wrote: post #2

This is deeply irresponsible by the CSNA and is a disaster just waiting to happen on the ground. Is it laziness on the part of their flight team or just crass disregard for others safety?

It is a calculated risk; perhaps similar to what have been done by the US and Russia when their space ambitions were at their highest.

You really should learn more about the history of the US program before making such ill informed statements.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#25

Post by jsjohnst »

throwaway4good wrote: post #15
throwaway4good wrote: post #13

Earlier quoted context omitted.

I also think there is a somewhat hyperbolic anti-China sentiment in the commentary on all of this. Plus a perhaps frustration at the US Space authorities on the lack of communication from their Chinese counterpart, something of course they themselves are entirely to blame for. Anyway; the Chinese have done a few of these "uncontrolled reentries" now. All crashing into the ocean; so they are either very lucky or it is…

Chances of not hitting land after n completely random reentriees is (71%)^n. That drops fairly fast.

You’re down into single digit percentage by the time n hits 7 in that case. What are we at, 4th re-entry? So 25% chance it lands in water given your formula. Given Chinese superstitions around the number 4, let’s hope this one has a safe and wet splashdown.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#26

Post by xenadu02 »

cycrutchfield wrote: post #10
throwaway4good wrote: post #8

Earlier quoted context omitted.

It is a calculated risk; perhaps similar to what have been done by the US and Russia when their space ambitions were at their highest.

Ah, the good old “whatabout the US did it 50 years ago therefore we can do it today”. Also used to justify all sorts of atrocities, imperialism, IP theft, etc.

As if two wrongs somehow make it right!

Uncontrolled re-entry of any debris likely to reach the ground without burning up is a bad idea. So is blowing anything up in orbit (creating huge hazards for other spacecraft).

These are bad ideas no matter who does them and the fact that anyone did so in the past is not an excuse for continuing the bad behavior.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#27

Post by holoduke »

Simon_O_Rourke wrote: post #2

This is deeply irresponsible by the CSNA and is a disaster just waiting to happen on the ground. Is it laziness on the part of their flight team or just crass disregard for others safety?

This is China in a nutshell. They don't give a fuck about what's happening around them. Unless it Harms their economic interest. Other than that they do not have any compassion for safety, environment etc. It might change in the future, but with this crazy regime I doubt people ever gonna care about it.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#28

Post by ch4s3 »

throwaway4good wrote: post #8
Simon_O_Rourke wrote: post #2

This is deeply irresponsible by the CSNA and is a disaster just waiting to happen on the ground. Is it laziness on the part of their flight team or just crass disregard for others safety?

It is a calculated risk; perhaps similar to what have been done by the US and Russia when their space ambitions were at their highest.

The US and Russia didn't do this. Both space programs either used upper stages to boost into orbit or were small enough to burn up on reentry. The Long March 5B has a giant rocket 20 metric ton that is too big to burn up and falls to Earth in an uncontrolled fashion.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#30

Post by gerad »

jsjohnst wrote: post #25
throwaway4good wrote: post #15

Earlier quoted context omitted.

Chances of not hitting land after n completely random reentriees is (71%)^n. That drops fairly fast.

You’re down into single digit percentage by the time n hits 7 in that case. What are we at, 4th re-entry? So 25% chance it lands in water given your formula. Given Chinese superstitions around the number 4, let’s hope this one has a safe and wet splashdown.

That’s not how the stats work. There’s a 71% chance it lands in water this time (and every time). If you flip heads 3 times in a row, it doesn’t mean you’re more likely to flip tails next time.
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