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SpaceX Discussion Thread


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9 minutes ago, kspbutitscursed said:

test the recovered ships and still see if they perform norminal after being recovered?

Long pole to land a Starship from space, but that's gold standard.

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5 hours ago, Exoscientist said:

  SpaceX repeating the same mistakes over and over again does not make those mistakes correct.

Just to be clear, what "mistake" is SpaceX repeating over and over again?

If it's "not doing a full duration burn," then you have to justify why that qualifies as a mistake.

If the qualification is "because raptors are unreliable," then you're wrong, because today's raptors are not the same as the ones that failed.  Besides, failures are expected in SpaceX's development process, and therefore not doing the type of test burn you think they should do no longer qualifies as a mistake.

 

If by "mistake," you mean "not following industry standard procedure (whatever that is)," then we should all be overjoyed that they're making that "mistake," because it sure seems to be working pretty well for them.

Edited by zolotiyeruki
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3 minutes ago, zolotiyeruki said:
5 hours ago, Exoscientist said:

  SpaceX repeating the same mistakes over and over again does not make those mistakes correct.

Just to be clear, what "mistake" is SpaceX repeating over and over again?

Not monitoring this forum more closely and therefore missing exo's advice, apparently.

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pretty sure spacex is sampling a wide array of mistakes. fix enough of them and you have a heavy launch platform. sure beats throwing a bunch of bureaucracy at the problem and hoping those pencil pushers caught something the engineers missed.

Edited by Nuke
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Let's try to avoid steering into ad hominem territory, but so far problems with the Raptor engine seem to either originate from side effects of being struck by debris, likely issues with the fuel supply or not being started up at all due to faulty attitude control. I don't see how testing the engine for minutes instead of seconds would solve these issues, since Raptor seems to be quite reliable once it's running.

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27 minutes ago, NFUN said:

cut SpaceX some slack; after all, we're making the same mistake over and over again right now

Congratulations! You won the forum!

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6 hours ago, tater said:

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I know it's dumb (especially since it'll be far outdated), but I really want them to reserve S42 for a Mars mission, even if it has to sit around until 2026 for the next launch window.

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 I highly value this thread: it recently alerted me to the opportunity to watch the fascinating IFT3 launch live.  (Thank you, tater.)

Comparatively speaking...

"Apollo was just engineers showing off."   Life was excruciatingly slow in the aerospace lane back then.  (I say this as someone who watched the original Moon landing, live, as a very excited/amazed 14 year-old.)

After 1969, the next time I got excited about anything in space was the 2016 arrival/capture of Juno at Jupiter.  I didn't even know it had been sent (in 2011).  Effectively no one cares about the details of mickey-mouse "science" experiments at the other end of the solar system, anyway.  "Scientists amusing themselves at everyone else's expense" .  Photographers, too.

Now, with SpaceX, exciting and ambitious rocketry experiments are being performed just about as fast as can be humanly imagined.  I can't get enough.  Yes, I wish SpaceX would hurry up: I relish the stimulation!

Truthfully, I do not care whether any SpaceX launch appears to succeed or fail.  Perfection is just an idol when you understand the true opportunity costs -- and it's a paymaster that pays only every five years, at a very minimum.

"I lived in the 1960s.  It was OK, I suppose, but I absolutely do not wish to return there!!"  (Like watching snails painting their nails.)  I'm betting most normal people agree with me on this.

(And in case it hasn't come across, everything SpaceX' current competitors are doing is thoroughly boring[truth].  I don't follow those zombie programs.  There are other threads for those, in any case (hint).)

Spoiler

So, how did we do?  Given that this IS the SpaceX thread, I'd say "All coments nominal, Boca Chica: we are ON topic...!".

 

Edited by Hotel26
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On 3/26/2024 at 1:41 PM, tater said:

What mistakes? When was the last 100% reusable (actually reusable, unlike Shuttle) rocket tested by anyone?

Why do people in this forum continue to take potshots at the Space Shuttle?

It was a fantastic system, that absolutely pioneered the practical reuse of space vehicles. Nearly every part of a shuttle was reused -- the only thing that wasn't was the external tank.

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On 3/26/2024 at 9:23 PM, sevenperforce said:

Not monitoring this forum more closely and therefore missing exo's advice, apparently.

Lol, I heard there is a user named "Endoscientist" who hangs around on a Blue Origin fan forum and actually gives them useful advice:P

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9 minutes ago, mikegarrison said:

Why do people in this forum continue to take potshots at the Space Shuttle?

It was a fantastic system, that absolutely pioneered the practical reuse of space vehicles. Nearly every part of a shuttle was reused -- the only thing that wasn't was the external tank.

I never said it wasn't fantastic—but it was not reusable in the sense that they are attempting with Starship (or even F9 boosters). Sorry, that's simply fact.

$1.3B per flight is not a real reusable vehicle. When Shuttle was proposed, they literally talked about flying it enough to make it cheaper than Titan—which required a cadence of about 1 per week on the nominal budget... that in the real world flew just a few times a year. I don't care how many parts were "reused," it needs to result in cheaper use, and higher cadence or it's a waste of time. It must be economical to reuse.

That's ACTUAL reuse. Cars are reusable. Planes are reusable. Ships are reusable. Shuttle wasn't. Orion isn't, DRAGON isn't, either. They are refurbishable.

Edited by tater
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3 minutes ago, mikegarrison said:

Why do people in this forum continue to take potshots at the Space Shuttle?

It was a fantastic system, that absolutely pioneered the practical reuse of space vehicles. Nearly every part of a shuttle was reused -- the only thing that wasn't was the external tank.

Beautiful vehicle, a marvel of engineering and an excellent first step towards rapid reusability and a sci-fi future, that we stuck with for decades and never got followed up with a second step.

The bulk of the troubles people tend to have with it is the gap between what it was billed as being able to do and what it actually did. Most of its turnaround, reusability, and cost goals were never reached. I'm all for aiming high, but you can't get something that ambitious right on the first try. Going from Apollo to 2001: A Space Odyssey in one step was never going to work, but they tried to get close with the one try they were allowed. We ended up with something that was promising but not particularly revolutionary. Instead of iterating on the shuttle (well, they did minor iterations), we kept the same design for 30 years and never committed to properly funding replacements or upgrades until after it was gone.

This was however largely a funding/political problem, though.

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8 minutes ago, mikegarrison said:

Why do people in this forum continue to take potshots at the Space Shuttle?

It was a fantastic system, that absolutely pioneered the practical reuse of space vehicles. Nearly every part of a shuttle was reused -- the only thing that wasn't was the external tank.

 

2 minutes ago, tater said:

I never said it wasn't fantastic—but it was not reusable in the sense that they are attempting with Starship (or even F9 boosters). Sorry, that's simply fact.

$1.3B per flight is not a real reusable vehicle. When Shuttle was proposed, they literally talked about flying it enough to make it cheaper than Titan—which required a cadence of about 1 per week on the nominal budget... that in the real world flew just a few times a year. I don't care how many parts were "reused," it needs to result in cheaper use, and higher cadence or it's a waste of time. It must be economical to reuse.

That's ACTUAL reuse. Cars are reusable. Planes are reusable. Ships are reusable. Shuttle wasn't. Orion isn't, DRAGON isn't, either. They are refurbishable.

To be a jerk nit-picker: The aerodymanic engineering of the shuttle airframe is definitely re-useable. The Soviets did it first, and now the Chinese and Indians have reused the shuttle design, because without hypothetical quantum CFD supercomputers, the airframe shape is as close to optimized as you can get for the mission.

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18 minutes ago, mikegarrison said:

the only thing that wasn't was the external tank.

The last External Tank contract was I think 2007. They were $172M each. In 2024 dollars that's $257M.

So the only part thrown away cost ~2.5X the entire Starship launch stack.

 

 

2 minutes ago, Meecrob said:

To be a jerk nit-picker: The aerodymanic engineering of the shuttle airframe is definitely re-useable. The Soviets did it first, and now the Chinese and Indians have reused the shuttle design, because without hypothetical quantum CFD supercomputers, the airframe shape is as close to optimized as you can get for the mission.

That's not what "reusable" means in this context. Loads of IDEAS are useful across many regimes. We're talking about a vehicle—and he's nit-picking when I EXPLICITLY said 100% reusable. So Shuttle definitionally does not count even if someone's definition of "reusable" includes Shuttle because he says in the reply except the external tank... so not 100% of Shuttle was reused—they are trying something completely new here.

On 3/26/2024 at 2:41 PM, tater said:

When was the last 100% reusable (actually reusable, unlike Shuttle) rocket tested by anyone?

 

^^^Point stands.

Edited by tater
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3 minutes ago, tater said:

I never said it wasn't fantastic—but it was not reusable in the sense that they are attempting with Starship (or even F9 boosters). Sorry, that's simply fact.

$1.3B per flight is not a real reusable vehicle. When Shuttle was proposed, they literally talked about flying it enough to make it cheaper than Titan—which required a cadence of about 1 per week on the nominal budget... that in the real world flew just a few times a year. I don't care how many parts were "reused," it needs to result in cheaper use, and higher cadence or it's a waste of time. It must be economical to reuse.

That's ACTUAL reuse. Cars are reusable. Planes are reusable. Ships are reusable. Shuttle wasn't. Orion isn't, DRAGON isn't, either. They are refurbishable.

The Space Shuttle was a fully functioning small space station that could house more than half a dozen people for a week in orbit, and you are comparing it to the cost of a titan launch?

Yes, an uncrewed reusable booster would have been cheaper for routine sat deliveries to orbit. Like most of crewed space flight, there is some question about whether it should even be done at all. The shuttle was designed to do everything for everyone, which usually doesn't end up making it ideal for anything or anyone. But the things you are complaining about here are ridiculous in terms of apples versus oranges.

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Definition would be that what sat on the launchpad gets restacked (or whatever, might be SSTO), and reflown with no major components having to be new by design.

Just now, mikegarrison said:

The Space Shuttle was a fully functioning small space station that could house more than half a dozen people for a week in orbit, and you are comparing it to the cost of a titan launch?

The POINT of shuttle was to replace expendable LVs back in the day. That was the sales pitch.

Regardless, you are arguing a straw man. I said 100% reusable. That means 100%, I didn;t say "largely reusable" or "partially reusable." So show me that Shuttle was 100% reused every launch, or you're making a nonsense argument.

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4 minutes ago, tater said:

Definition would be that what sat on the launchpad gets restacked (or whatever, might be SSTO), and reflown with no major components having to be new by design.

So by that definition there has not yet ever been any reusable space launch?

(Except, I guess, Blue Origin's New Shepard? Or, perhaps the X-15 and the Virgin Galactic?)

Edited by mikegarrison
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4 minutes ago, tater said:

The last External Tank contract was I think 2007. They were $172M each. In 2024 dollars that's $257M.

So the only part thrown away cost ~2.5X the entire Starship launch stack.

 

 

That's not what "reusable" means in this context. Loads of IDEAS are useful across many regimes. We're talking about a vehicle—and he's nit-picking when I EXPLICITLY said 100% reusable. So Shuttle definitionally does not count even if someone's definition of "reusable" includes Shuttle because he says in the reply except the external tank... so not 100% of Shuttle was reused—they are trying something completely new here.

 

^^^Point stands.

I appreciate that you are enthusiastic about your point, but you neglected to notice that I am SUPPORTING your point.

The shuttle is not "fully" re-useable. I get what you are saying lol.

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Just now, mikegarrison said:

So by that definition there has not yet ever been any reusable space launch?

NO. Did you not read my post you replied to?

"When was the last 100% reusable (actually reusable, unlike Shuttle) rocket tested by anyone? "

100%. What part of that is unclear? That means, um 100%. So never been done by anyone, ever.

 

Nixon announcing the Shuttle program:

https://www.nasa.gov/history/president-nixons-1972-announcement-on-the-space-shuttle/

Quote

The new system will differ radically from all existing booster systems, in that most of this new system will be recovered and used again and again—up to 100 times. The resulting economies may bring operating costs down as low as one-tenth of those present launch vehicles.

So from inception designed to be (aspirationally) 1/10the cost of expendable LVs.

Quote

The general reliability and versatility which the Shuttle system offers seems likely to establish it quickly as the workhorse of our whole space effort, taking the place of all present launch vehicles except the very smallest and very largest.

So replacing all launch except maybe Saturn V sized stuff and... smallsat scaled launchers?

 

I should add that it will not have been done by anyone, ever, until a landed system is restacked, and reflown. Still a LONG pole for SpaceX.

 

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