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SpaceX SN9 Explodes on Landing

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Re: SpaceX SN9 Explodes on Landing

#271

Post by sudosysgen »

alentist wrote: post #268
sudosysgen wrote: post #248

Earlier quoted context omitted.

A significant reason why Stalin was able to successfully rise to power and why the Bolsheviks were able to secure total power is because of foreign violence and interference. When all major foreign powers say that they wish for the destruction of your country and would openly prefer you to go back to more suffering, support for monsters like Stalin increases. Equally, when the threat of invasion is as high as it was…

You completely dodged the question and tried to change the subject, so I'll ask it again: If they had such a wonderful society, why did they have to systematically mass murder people who wanted to leave this wonderful society?

They did not have a wonderful society. It was very deficient in many ways. I didn't argue that point because we agree. The point I'm arguing is whether or not the USSR could have had a better society if it wasn't for US and other foreign intervention, and the answer is an unequivocal yes.

Re: SpaceX SN9 Explodes on Landing

#272

Post by Layke1123 »

alentist wrote: post #269
Layke1123 wrote: post #238

Earlier quoted context omitted.

Well, why did the US actively try to harm the USSR? If it was such a bad way of doing things, why did the US actively go out of it's way to sabotage it rather than just ignore it and let it die?

You completely dodged the question and tried to change the subject, so I'll ask it again: If they had such a wonderful society, why did they have to systematically mass murder people who wanted to leave this wonderful society? Your question, on the other hand, is silly. Substitute the USSR with Nazi Germany.

Why did the US have to systemically mass murder Native Americans and enslave Africans Americans and fight over seas wars in Vietnam and North Korea? If you can assert their atrocities, I can so also assert the US's. You are dodging, not me.

Re: SpaceX SN9 Explodes on Landing

#273

Post by Layke1123 »

Cogito wrote: post #252
Layke1123 wrote: post #238

Earlier quoted context omitted.

Well, why did the US actively try to harm the USSR? If it was such a bad way of doing things, why did the US actively go out of it's way to sabotage it rather than just ignore it and let it die?

This is moving the goalposts. It's possible that the USSR would have been a better system, had the cold war not happened, but that's not the world we live in. If you want to make that argument you have to explain why it's reasonable to excuse how the USSR turned out in reality, and why in your hypothetical world it would have turned out differently. With respect to space advancement, I suspect the main reason for sus…

It's not moving to goalposts to acknowledge that the USSR beat us to space and that a large part of their collapse was due directly to the influence of the US.

Re: SpaceX SN9 Explodes on Landing

#274

Post by Layke1123 »

sudosysgen wrote: post #271
alentist wrote: post #268

Earlier quoted context omitted.

You completely dodged the question and tried to change the subject, so I'll ask it again: If they had such a wonderful society, why did they have to systematically mass murder people who wanted to leave this wonderful society?

They did not have a wonderful society. It was very deficient in many ways. I didn't argue that point because we agree. The point I'm arguing is whether or not the USSR could have had a better society if it wasn't for US and other foreign intervention, and the answer is an unequivocal yes.

Exactly! They can't even consider the possibility it seems because they don't want to even consider it. Its almost as entrenched as what some might call faith that the US was superior to the USSR and if you even suggest the idea of anything else you are downvoted because you are the bad guy for even considering it.

Re: SpaceX SN9 Explodes on Landing

#275

Post by naikrovek »

bacon_waffle wrote: post #183
naikrovek wrote: post #162

Earlier quoted context omitted.

I don't recall NASA ever doing a rocket landing so I'm not sure which mistakes you are seeing repeated.

I was surprised to learn recently that NASA did do some rocket landings in the 90s: https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X

Ok, so which mistakes is SpaceX making that NASA also made?

Re: SpaceX SN9 Explodes on Landing

#276

Post by naikrovek »

sudosysgen wrote: post #247
naikrovek wrote: post #162

Earlier quoted context omitted.

I don't recall NASA ever doing a rocket landing so I'm not sure which mistakes you are seeing repeated.

NASA and the USSR did many powered rocket landings, actually. NASA even had a program for reusable first stages via powered landings that was scrapped because automatic guidance wasn't feasible yet.

Ok, so which mistakes is SpaceX making that NASA also made?

Re: SpaceX SN9 Explodes on Landing

#277

Post by naikrovek »

minikites wrote: post #251
naikrovek wrote: post #162

Earlier quoted context omitted.

I don't recall NASA ever doing a rocket landing so I'm not sure which mistakes you are seeing repeated.

NASA did rocket landings on another planet with 1970s technology: https://en.wikipedia.org/wiki/Viking_program#Entry,_Descent_... >At an altitude of about 1.5 kilometers (5,000 feet), the lander activated its three retro-engines and was released from the parachute. The lander then immediately used retrorockets to slow and control its descent, with a soft landing on the surface of Mars.

Ok, so which mistakes is SpaceX making that NASA also made?

Re: SpaceX SN9 Explodes on Landing

#278

Post by sudosysgen »

naikrovek wrote: post #276
sudosysgen wrote: post #247

Earlier quoted context omitted.

NASA and the USSR did many powered rocket landings, actually. NASA even had a program for reusable first stages via powered landings that was scrapped because automatic guidance wasn't feasible yet.

Ok, so which mistakes is SpaceX making that NASA also made?

Failing to restart an engine in a retrograde trajectory. A difficult task that both the Soviets and NASA (and Arianespace and the Chinese) had issues with, but worked out.

It's very difficult because of the turbulent airflow in an engine bell pointed against the airspeed vector. Despite this, many rocket engines can do it reliably.

Re: SpaceX SN9 Explodes on Landing

#279

Post by ew6082 »

laverya wrote: post #208
WalterBright wrote: post #202

Earlier quoted context omitted.

The sheets of stainless steel appear to have separated at the joints. This says the sheets are stronger than the joints, meaning they're overweight :-)

I was thinking something similar myself (more on weld quality, "welds should be as strong as the rest of the material"), but then I realized that this doesn't matter , and having an unoptimized test vehicle a week earlier is always going to be the better option for SpaceX. 1. Is it light enough to fly? 2. Is it strong enough to not cause a failure? #shipit

A static weld is usually stronger than the base metal under static conditions (i.e. not undergoing dynamic shock loading). Welds are created at 3000 degrees C with 50-100C metal right next to it. By the time a weld cools there are always captive stresses, meaning during a failure the weld is the most brittle part. This can be alleviated with pre and post weld heat treatment, but there are always stresses built into a weld.

Re: SpaceX SN9 Explodes on Landing

#280

Post by alentist »

Layke1123 wrote: post #272
alentist wrote: post #269

Earlier quoted context omitted.

You completely dodged the question and tried to change the subject, so I'll ask it again: If they had such a wonderful society, why did they have to systematically mass murder people who wanted to leave this wonderful society? Your question, on the other hand, is silly. Substitute the USSR with Nazi Germany.

Why did the US have to systemically mass murder Native Americans and enslave Africans Americans and fight over seas wars in Vietnam and North Korea? If you can assert their atrocities, I can so also assert the US's. You are dodging, not me.

You again keep trying to dodge the question and change the subject, so I'll ask it yet again: If the USSR had such a wonderful society, why did they have to systematically mass murder ordinary people who wanted to leave this wonderful society?

If you're saying that slavery is also abhorrent and evil—like the slavery and mass murder that takes place under Communism—then we're in agreement. Now, can you please answer the question?

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