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Super Heavy has splashed down in The Gulf of Mexico

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Re: Super Heavy has splashed down in The Gulf of Mexico

#771

Post by rbanffy »

cryptonector wrote: post #287
golol wrote: post #239

Earlier quoted context omitted.

Exactly. Everyone was worried about reentry, but perhaps more concerning than the question of whether the headshield tiles work was the question how well the material below can handle failures. Now we know significant failures of tiles do not have to lead to mission loss.

Failure of the tanks would undoubtedly have been catastrophic. Partial failure of a flight control surface proved survivable.

It's not unheard of planes landing after losing a full wing. You need a lucky and competent pilot to do that.

Re: Super Heavy has splashed down in The Gulf of Mexico

#772

Post by rbanffy »

cubefox wrote: post #587
mathsmath wrote: post #360

Earlier quoted context omitted.

It's also worth noting part of the craft flew (intentionally) without heat tiles, and another part with thinner tiles. They're gathering a ton of data to make it robust! Many of these engineers built Falcon 9, and I have a pretty high degree of confidence they'll shake out the issues. SpaceX operates very differently from traditional aerospace, so we'll likely see many more issues come up before Starship is human rat…

Getting it human rated is likely much harder than reusing the upper stage a couple of times. The difficulty is that Starship has 1) no launch abort system, and 2) the belly flop landing is much more dangerous than conventional and proven capsule based landing. To get the system human rated, they may have to fly tens or even hundreds of flawless cargo missions first.

> To get the system human rated, they may have to fly tens or even hundreds of flawless cargo missions first.

Each lunar flight implies four launches and three landings on Earth, so the numbers should build up rather quickly.

Re: Super Heavy has splashed down in The Gulf of Mexico

#773

Post by rbanffy »

GuB-42 wrote: post #736
dragonsky67 wrote: post #594

Earlier quoted context omitted.

I love that they are deliberately tempting failures with the no and thin tiles. In a lot of ways they will learn far more from the heat shield burn through around the flap(s) than they would have if they had been "lucky" and it had all gone perfectly. You during testing you want things to fail, that is the point of testing. If it's all successful you only learn that under those conditions your design works, but if it…

That's an often underappreciated aspect of engineering. When parts last longer than expected, it is considered something that needs "fixing". It is a signal that the part can be made cheaper, lighter, etc... If SpaceX had gone with heavy, thick tiles, and they did their job because they were overspecced, it is that much less payload capacity. Even value engineering, which is often criticized when it comes to consumer…

It'll still be orders of magnitude cheaper than the nearest competitor for many years. They don't need to fix it before gaining very extensive experience flying it.

Re: Super Heavy has splashed down in The Gulf of Mexico

#774

Post by me_me_me »

somenameforme wrote: post #726
imtringued wrote: post #679

Earlier quoted context omitted.

Why does this matter? The delta V requirements are so steep Starship can't return from the martian surface. It is a completely different game to go to Mars than to the moon unless you are planning on building a mars gateway in orbit and never landing anywhere.

Oh this opens a whole bunch of really interesting topics. One of the most interesting is ISRU - in situ resource utilization. Using what you have available to make further progress. The Sabatier Reaction [1] is one of the single most important factors in our future expansion. Basically, CO2 + Hydrogen => Methane + Water. Mars has essentially infinite CO2 and hydrogen. So this means we can produce essentially infinite…

more interestingly, the impact on human psyche is basically unknown. We have meh approximations but just like placebo you cannot fake some things, like 'you are not coming back' condition in an experiment.

The permanent dwellings and really whole infrastructure would be underground. Lack of atmo and magnetic field basically forces you to dig down. Limited resources - rudimentary food and water. More less bunker life

On top of that 0% prospect of return. Essentially you are doomed to penal colony for the rest of your life.

I find it hard to believe anyone would want to sign up to that. And the people who would are absolutely people who should not be sent there.

And what happens if earth decides supporting mars outpost is pointless, you want alex jones types create conspiracies that colony is fake and its a tax payer scam? What would that do to minds of those stuck on mars?

Re: Super Heavy has splashed down in The Gulf of Mexico

#775

Post by rbanffy »

brookst wrote: post #769
rbanffy wrote: post #762

Earlier quoted context omitted.

He doesn't give many Star Trek vibes though. Space Socialism isn't really his thing. What he could do (and Blue Danube yesterday gave me the idea) is to buy the PanAm brand and do a rebrand of the crew services at least to the ISS.

I could definitely see Musk getting into Make Pan American Great Again.

Please don't ruin it ;-)

Re: Super Heavy has splashed down in The Gulf of Mexico

#776

Post by AlgorithmicTime »

rbanffy wrote: post #762
andromaton wrote: post #476

Earlier quoted context omitted.

Bet he will

He doesn't give many Star Trek vibes though. Space Socialism isn't really his thing. What he could do (and Blue Danube yesterday gave me the idea) is to buy the PanAm brand and do a rebrand of the crew services at least to the ISS.

[dead]

Re: Super Heavy has splashed down in The Gulf of Mexico

#777

Post by kobalsky »

world2vec wrote: post #254

Seeing the Starship's flap visibly burning in the reentry heat and still survive well enough to move around and get to a splashdown was just incredible. Amazing progress in just four test flights.

saw that and wondered how do they go from there to reusable. is the shileding ablative and replaced on every flight?

Re: Super Heavy has splashed down in The Gulf of Mexico

#778

Post by meigwilym »

stctw wrote: post #406
amanaplanacanal wrote: post #391

Earlier quoted context omitted.

Firebombing whole cities in Europe and Japan is still a black mark in US history. It’s really hard for me to get “holier than thou” on other terror campaigns when I remember that.

It's easy to say that now. Have you lived through unrestricted, total warfare, where one side intends to conquer a continent or the world, invades without provocation, and won't stop until brought to submission through extreme force? The Allies did not initiate war and did not want war. How many of your country's people should you sacrifice to end a war of aggression started by the enemy? Should you not use the means…

The firebombing of Dresden needlessly killed thousands of civilians, and arguably did nothing for the war effort. With the posisble exception of bolstering the resolve of front line German soldiers.

Had the axis powers won the war I'm certain it would have been classified as a war crime and Bomber Harris would have been the first against the wall.

Re: Super Heavy has splashed down in The Gulf of Mexico

#779

Post by lief79 »

Paddywack wrote: post #755
dylan604 wrote: post #434

Earlier quoted context omitted.

The thing that tickles me is that it has to slow down to reach terminal velocity rather than the normal way of thinking about objects speeding up to reach terminal velocity.

I’m not a scientist, but is it not at terminal velocity for most of the way down by definition? So it’s not slowing down to reach terminal velocity, it’s just that the resistance becomes higher thus reducing terminal velocity?

Terminal velocity is the fastest speed it would accelerate to via the pull of gravity versus air resistance. In space, there is no air, hence no terminal velocity.

If the object is heating up due to air resistance (and compressed air), then it's moving far faster than terminal velocity. The heat is from the air getting compressed and slowing it down.

Re: Super Heavy has splashed down in The Gulf of Mexico

#780

Post by pmontra »

xcv123 wrote: post #544
FredPret wrote: post #541

Earlier quoted context omitted.

Conditional surrender would have been completely unacceptable given that they were the aggressor and had a million troops in China, and wanted to hold on to their conquests after the war. Even after the first nuke they didn't surrender. It took the emperor speaking up - for the first time ever - after the second nuke, and even then the military junta tried to stop it. Your points about the Communists stand, but keep…

> Conditional surrender would have been completely unacceptable And some would argue that nuking entire cities is completely unacceptable.

Nuking cities or conventional bombing them is the same thing. The bombing of Tokyo resulted in about 100 k deaths https://en.wikipedia.org/wiki/Bombing_of_Tokyo

Only the emotional impact was different. A nuke was an otherworldly weapon that marked a technological superiority that was impossible to overcame during the war, hence the surrender. Carpet bombing would have to go on until enough Japanese cities and industries were reduced to hash. Then maybe an invasion. As somebody pointed out, the surrender of the Japanese troops in China was a goal of the war and they could not carpet bomb or nuke China.

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