An always cool Falcon 9 launch (and other Space News)

[manikyath]

1 minute ago, Uttamattamakin said:

There is a reason the one big rocket with a lot of small engines approach hasn't worked for anyone yet.  

because so far only the soviets have tried, and they had a horrid habit of not testing if the engines were actually functional after integrating them into the lower stage. 

 

just a few wikipedia snippets that may indicate why the N1 was flawed in procedure, as opposed to flawed in design:

Quote

the engines for Block A were only test-fired individually and the entire cluster of 30 engines was never static test fired as a unit.

Quote

only two out of every batch of six engines were tested, and not the units actually intended for use in the booster.

Quote

All four uncrewed launches ended in failure before first-stage separation. The longest flight lasted 107 seconds, just before first-stage separation.

 

you're like someone looking at the wright brothers trying to achieve flight going "there's a reason no one has managed to fly yet."

 

9 minutes ago, Uttamattamakin said:

Rather than plumbing together 33 engines in one big system... break it into several clusters of plumbing systems.  Separate tanks and internals....

this would singificantly increase the size of the rocket, and significantly increase complexity. it's more plumbing, more bulkheads, more valves, more fill levels to monitor (the booster doesnt necessarily use all engines equally)

 

and again.. they made it past the "operating stage" of the booster, so clearly it works..

[HenrySalayne]

18 minutes ago, Uttamattamakin said:

Even in fully expendable mode?  

Saturn V and SLS can put more than 40 tons on a lunar transfer. Falcon Heavy can do maybe 15 tons in fully expendable and 7 tons in Recovery mode.

18 minutes ago, Uttamattamakin said:

I hope I am wrong

You are wrong in hindsight of the last test flight. The Super Heavy worked flawlessly through stage separation - only the RTLS sequence didn't happen as planned and they basically demonstrated Super Heavy in expandable mode.

 

18 minutes ago, Uttamattamakin said:

There is a reason the one big rocket with a lot of small engines approach hasn't worked for anyone yet. 

The N1 was built by a delusional nation without open criticism and free speech in a hurry to compete with the systemic enemy in a run for the moon. That's pretty much a guarantee for disaster.

[Uttamattamakin]

3 minutes ago, manikyath said:

because so far only the soviets have tried, and they had a horrid habit of not testing if the engines were actually functional after integrating them into the lower stage. 

At that time going into the moon rate the USSR had about the same record as the USA.  They did cover up failures but had met most major milestones before we did to that point.  

 

Also you know the engines you are talking about.. those engines, or a variant of those engines, made in USSR times have been used on the Atlas 5.  Russia makes a lot of crap but their rockets are pretty good.  

3 minutes ago, manikyath said:

 

just a few wikipedia snippets that may indicate why the N1 was flawed in procedure, as opposed to flawed in design:

 

you're like someone looking at the wright brothers trying to achieve flight going "there's a reason no one has managed to fly yet."

Riiight.  Argumentum ad hominem really proves your point.   

 

I'm more like someone looking at the major competitor of the Wright Brothers competitor,  Sam Langley who did the same thing as others had but bigger and saying that won't work.  

 

As for comparing Space X to the Wright brothers... Rocketry had that moment a long time ago.  Same time as the Wrights first flight  or there about.   Space X is a lot of things but they are not like the Wright brothers. lol. 

 

3 minutes ago, manikyath said:

 

this would singificantly increase the size of the rocket, and significantly increase complexity. it's more plumbing, more bulkheads, more valves, more fill levels to monitor (the booster doesnt necessarily use all engines equally)

 

and again.. they made it past the "operating stage" of the booster, so clearly it works..

They will have "made it past the operating stage" when it does not blow up.

It's like saying a airliner that blows up as soon as you get off it is operational. 

[manikyath]

1 minute ago, Uttamattamakin said:

They will have "made it past the operating stage" when it does not blow up.

they passed staging, even if they never get the booster anywhere beyond the point it got today, it is a perfectly operational expendable booster, just like anything else on the market today except for falcon 9.

[HenrySalayne]

2 minutes ago, Uttamattamakin said:

It's like saying a airliner that blows up as soon as you get off it is operational. 

That was literally the standard for rockets until very recently!

[manikyath]

Just now, HenrySalayne said:

That was literally the standard for rockets until very recently!

it's really funny to put it like that.. i'm now trying to imagine a world where airliners just dump a passenger capsule over major cities to parachute down, while the rest of it flings off into the ocean somewhere.

[Uttamattamakin]

6 minutes ago, HenrySalayne said:

Saturn V and SLS can put more than 40 tons on a lunar transfer. Falcon Heavy can do maybe 15 tons in fully expendable and 7 tons in Recovery mode.

You are wrong in hindsight of the last test flight. The Super Heavy worked flawlessly through stage separation - only the RTLS sequence didn't happen as planned and they basically demonstrated Super Heavy in expandable mode.

Flawless. 

 

I guess Starship which was on trajectory and seemed fine also blowing up was flawless too eh? 

6 minutes ago, HenrySalayne said:

 

The N1 was built by a delusional nation without open criticism and free speech in a hurry to compete with the systemic enemy in a run for the moon. That's pretty much a guarantee for disaster.

The way that Space X is competing, in its mind and the mind of many of its supporters, with NASA.  In a race where SLS got it's payload up and around the moon without detonating. 

 

3 minutes ago, HenrySalayne said:

That was literally the standard for rockets until very recently!

Which ones?  Those rockets were designed to be expendable.  The manned parts came back just fine.   The purpose and function is to get payload and people to space and back safely.  Right now starship can't get past the gulf of Mexico without blowing up.   I get it many here are fans of Musk ask more of him. 

[manikyath]

Just now, Uttamattamakin said:

Right now starship can't get past the gulf of Mexico without blowing up.   I get it many here are fans of Musk ask more of him. 

yes.. very big fans of musk.. that's totally what's going on here..

 

maybe i should just respond to anything you say that you're obviously just angry because elon is ruining twitter.. despite SpaceX's success essentially having nothing to do with the man himself, other than him owning the party.

 

3 minutes ago, Uttamattamakin said:

Which ones?  Those rockets were designed to be expendable.  The manned parts came back just fine.

there is no payload in this flight to speak of, it is a prototype on a test flight. - starship is also initially going to be strictly cargo (as far as NASA is concerned.), because we as humanity learned from the shuttle that launch escape systems are very important on manned flights.

[HenrySalayne]

7 hours ago, Uttamattamakin said:

Which ones?  Those rockets were designed to be expendable.  The manned parts came back just fine.   The purpose and function is to get payload and people to space and back safely.  Right now starship can't get past the gulf of Mexico without blowing up.   I get it many here are fans of Musk ask more of him. 

You do know booster recovery is optional? It's not mission crirical but a cost saving factor. Even Starship will only successful land 50% throughout its first service years.

 

You can take a look at Falcon 9 and how long it took there to get the booster down nice and soft repeatedly. Super Heavy has to be picked out of the air by two giant chopsticks - it's out of the question this will take at least a dozen landing attempts to work most of the time.

[wanderingfool2]

9 hours ago, Uttamattamakin said:

Right now starship can't get past the gulf of Mexico without blowing up

Except that it managed to essentially do what they were hoping to do in the TEST.

 

Do you seriously not understand that, or lack the ability to understand that in a test campaign they have set targets and if they surpass the targets that's great (they have plans for that).  An explosion like they had was not a failure and quite honestly both ships probably got further than they had expected.

 

The first starship launch, which used a never before flown booster was set as having a high probability of not even exiting the launch pad.  They had hopes it would work perfectly, but they weren't even sure the stage separation would work correctly.

 

The second starship introduced the hot staging (and lets be honest, they switched to hotstaging because I think they recognized the other method was introducing an issue).  They honestly weren't sure if the hotstaging would damage the booster to the point of not being able to fly.  Sure they had hopes things would work out perfectly, but they knew there would be likelyhood of some damage or even failing and terminating both at that point.

 

Even the heat shielding...they believed there would be a decent shot that it would burn up on reentry because the way they have the tiles mounted isn't perfected yet...but it is good data to see just how far you can push it (and how many tiles can be lost and still have a successful reentry)

 

9 hours ago, manikyath said:

we as humanity learned from the shuttle that launch escape systems are very important on manned flights.

From my understanding, there might actually be no realistic way to ever meet the current requirements for takeoff for a human escape system (as you effectively can't boost away from it properly).  Although I think there was talks about not requiring it for the boost portion if reliability can be proven (or that the starship can act as the escape vessel if the booster fails)

[CarlBar]

  

On 11/18/2023 at 10:48 PM, Kisai said:

I would rather "build it right the first time", the method that engineers used before computers were a commodity,

 

This almost never happened before computers. You just didn't know about all the prototype and scale model failures they went through in the process before you saw the final working well form. All of that was done behind proverbial closed doors. A mixture of SpaceX's openness and modern social media mean you hear about SpaceX's failures more than you would in the past.

 

For that matter when developing the Saturn V they blew up quite a few engines on the test stand diagnosing a combustion instability problem. But AFAIK that wasn't public knowledge until much more recently.

 

The N1 was a trainwreck for one really big reason. None of the engines that went on the rocket were lit prior to the launch. They'd take some engines from the same production batch and test fire them, but due to how it was lit it just couldn't light it more than once, so none of the engines that went on the final launch vehicles were ever test fired. This is pretty much exactly the opposite of how every successful rocket has done things. Test firing an engine confirms it's functional. Better yet, test firing it on the vehicle it's going to fly on confirms that it's installed right, and this is something that again most successful rockets do, (including SLS).

 

20 hours ago, Mark Kaine said:

I thought i know most about this stuff, but apparently Scott Manley failed me... i knew they would need to do more testing i just thought the design was finalized.

 

I recommend Marcus House almost every week he does a space news roundup that covers everything going on at starbase, (and also other stuff around the world, but starbase is the focus, Scott Manley often catches non-spaceX stuff he misses), including all the tests and known changes. One major change coming in i think the next booster is electric actuators for the gimbling instead of hydraulic.

 

The Launch mount isn't even finalised, we know the final form is going to have a water cooled shell put over almost everything that currently gets exposed to exhaust, but it's not a priority during development as the repairs needed after a launch, (or more likely several launches), don't slow down the launch rate.

 

Same reason they originally tried to go with a purely concrete pad, they thought it would hold up to the exhaust well enough for the first several launches and it saved them months of delays while the design was finalized and months more while it was built. They ended up guessing wrong on that, but based on after the fact analysis it was apparently a foundation related failure rather than the slab itself that gave first, so their estimate the slab would hold was good, but they didn't properly account for the foundation factors.

[Kisai]

2 hours ago, CarlBar said:

  

 

This almost never happened before computers. You just didn't know about all the prototype and scale model failures they went through in the process before you saw the final working well form. All of that was done behind proverbial closed doors. A mixture of SpaceX's openness and modern social media mean you hear about SpaceX's failures more than you would in the past.

 

For that matter when developing the Saturn V they blew up quite a few engines on the test stand diagnosing a combustion instability problem. But AFAIK that wasn't public knowledge until much more recently.

 

Again, this is about public perception. If you want the public to support space exploration, you can't keep blowing stuff up in the atmosphere and having it rain down on the planet, or leave debris in orbit. The more this happens, the more negative sentiment there is regarding sending anything into space. We also had this issue with nuclear weapons testing. The public does not like paying for private companies, let alone governments environmental contamination.

 

When the space race was in it's prime, it was always secretly, or not-so-secretly for military purposes. The public was more afraid of the more secretive communist bogeyman.  That hasn't existed in 30 years. Nobody really cares about the Chinese space program today because they're just doing it for propaganda purposes. They have not innovated anything that we haven't seen before from the US or Soviet space program.

 

Computers are at a scale now that you should not need to "blow things up on the pad", if you're blowing stuff up on the pad, you've cut too many corners. That is google style "rapid iteration" development that just should not be a thing when it comes to putting things on giant sticks of dynamite.

[Mark Kaine]

3 hours ago, CarlBar said:

This almost never happened before computers.

i agree... i also understand the need for real life testing. what i have issues with is the marketing gimmicks everything surrounding spaceX/musk... guy just does way too much "for show" and can't be trusted in any way...

also seems to change his mind constantly, which is obviously counter productive as its also wasteful af.

 

 

3 hours ago, CarlBar said:

recommend Marcus House

probably blocked like all spacex fanbois on yt, tbh.

 

Scott Manley is about the only "coverage" i watch, because i have the feeling he's at least neutral,  and typically has better footage / analysis than everyone else.  (doesn't mean i necessarily pay attention,  sometimes i have this stuff just running in the background,  it's not like techmoan, dawid does tech stuff, or mentour pilot where im pretty much glued to the screen :p) 

[Mark Kaine]

47 minutes ago, Kisai said:

Again, this is about public perception. If you want the public to support space exploration, you can't keep blowing stuff up in the atmosphere and having it rain down on the planet, or leave debris in orbit. The more this happens, the more negative sentiment there is regarding sending anything into space. We also had this issue with nuclear weapons testing. The public does not like paying for private companies, let alone governments environmental contamination.

 

When the space race was in it's prime, it was always secretly, or not-so-secretly for military purposes. The public was more afraid of the more secretive communist bogeyman.  That hasn't existed in 30 years. Nobody really cares about the Chinese space program today because they're just doing it for propaganda purposes. They have not innovated anything that we haven't seen before from the US or Soviet space program.

 

Computers are at a scale now that you should not need to "blow things up on the pad", if you're blowing stuff up on the pad, you've cut too many corners. That is google style "rapid iteration" development that just should not be a thing when it comes to putting things on giant sticks of dynamite.

that's the thing, as much spacex got maybe right, everything musk does has a massive negative impact on the environment,  i just want him to stop with his insanities... i know that's illusional as he never will, but that doesn't mean i have to support him lol. 

[Sauron]

52 minutes ago, Kisai said:

Again, this is about public perception. If you want the public to support space exploration, you can't keep blowing stuff up in the atmosphere and having it rain down on the planet, or leave debris in orbit. The more this happens, the more negative sentiment there is regarding sending anything into space. We also had this issue with nuclear weapons testing. The public does not like paying for private companies, let alone governments environmental contamination.

 

When the space race was in it's prime, it was always secretly, or not-so-secretly for military purposes. The public was more afraid of the more secretive communist bogeyman.  That hasn't existed in 30 years. Nobody really cares about the Chinese space program today because they're just doing it for propaganda purposes. They have not innovated anything that we haven't seen before from the US or Soviet space program.

 

Computers are at a scale now that you should not need to "blow things up on the pad", if you're blowing stuff up on the pad, you've cut too many corners. That is google style "rapid iteration" development that just should not be a thing when it comes to putting things on giant sticks of dynamite.

Additionally, during the actual space race NASA was constantly walking on the razor's edge where a major test failure could have meant the scrapping of the entire project. Obviously mistakes were made occasionally, most infamously the Apollo 1 fiasco, but they were all immediately followed up by extremely thorough investigations to ensure they would never happen again and heads rolling across the board.

 

You can't run a space rocket company like any old tech startup. Failure here means loss of life.

[Mark Kaine]

16 hours ago, HenrySalayne said:

Saturn V and SLS can put more than 40 tons on a lunar transfer. Falcon Heavy can do maybe 15 tons

you also have to wonder why we need "heavy lifters" for the moon (or, worse, "mars" lmao) other than for the profileration of an aging "space agency" and a single narcissist ...

 

don't we have better things to do? no? 

*sigh* 

[manikyath]

6 hours ago, Mark Kaine said:

that's the thing, as much spacex got maybe right, everything musk does has a massive negative impact on the environment,  i just want him to stop with his insanities... i know that's illusional as he never will, but that doesn't mean i have to support him lol. 

SpaceX < = > Elon Musk. perhaps it'll help you if you learn to separate a corporation from it's nutcase CEO.

 

6 hours ago, Mark Kaine said:

probably blocked like all spacex fanbois on yt, tbh.

perhaps you should also learn to see the difference between fanboys and people who are just excited to see rockets. i prefer nasaspaceflight, because they're just enthousiastic about all of it. they started with shuttle launches as the name implies, but these days they'll cover just about anything they can point a camera at that's pointed into space. they'll also totally make a jab at ex-twitter while covering SpaceX stuff. they're not there for 'fanboying' anything, they're there for the boom.

 

6 hours ago, Mark Kaine said:

you also have to wonder why we need "heavy lifters" for the moon (or, worse, "mars" lmao) other than for the profileration of an aging "space agency" and a single narcissist ...

 

don't we have better things to do? no? 

*sigh* 

because science. look up "the element hunt" if you want to learn more about the fun things humanity does just because it's interesting to know what's out there.

(and because a lot of the space technology ends up trickling down to us normal plebs, that little heat pump that was featured on LTT a while back can be traced back to research done for the appolo space program)

[Mark Kaine]

35 minutes ago, manikyath said:

because science. look up "the element hunt" if you want to learn more about the fun things humanity does just because it's interesting to know what's out there.

(and because a lot of the space technology ends up trickling down to us normal plebs, that little heat pump that was featured on LTT a while back can be traced back to research done for the appolo space program)

i agree, space exploration is important... i was just questioning the specific purpose of heavy lifters, especially new ones... especially with "crew"... is falcon heavy (that's how its called right?) really going to be that much cheaper... but then he wants to go to mars, instead of io or europa, etc.?

 

*categorically against*  

 

 

Spoiler

well, maybe not io

 

 

"Jupiter's moon Io is the most volcanically active world in the Solar System, with hundreds of volcanoes, some erupting lava fountains dozens of miles (or kilometers) high." 

 

 

 

[manikyath]

4 minutes ago, Mark Kaine said:

is falcon heavy (that's how its called right?)

falcon heavy is 3 falcons strapped together, this thing is called "starship"

 

5 minutes ago, Mark Kaine said:

but then he wants to go to mars, instead of io or europa, etc.?

this is where i suggest to separate the wild dreams of the nutcase at the top from what the engineers are doing.

 

in the short term, starship will do two things:

- significantly reduce the cost of LEO satalites, for stuff like satalite based internet connectivity.

- take humanity (not just "humans" but "our stuff" in general) back to the moon. the moon itself has fairly neglible scientific value, but there's some rocketry and space theory in using the moon to fling satalites into the solar system with less fuel burned by using the moon's gravity rather than just burning. bringing stuff to the moon is also a good "proof of concept" for the things we may take to a place that is more interesting.

 

in the long term, mars is the logical next step, because in space terms, it is a very similar planet to ours.. as well as being our closest neighbor. wether we actually ever bring humans there will depend on if anyone is willing to fund such an expedition, and if anyone is willing to go on such an expedition.

[wanderingfool2]

15 minutes ago, Mark Kaine said:

i agree, space exploration is important... i was just questioning the specific purpose of heavy lifters, especially new ones... especially with "crew"... is falcon heavy (that's how its called right?) really going to be that much cheaper... but then he wants to go to mars, instead of io or europa, etc.?

Heavy lifters will always be important in space flight with the current planned missions.

 

Specifically fairing sizes on those heavy lifters are large enough to make new things feasible.  For example, JWST had to have the folding mirrors to reach it's current size (and a lot of extra R&D to fit into the 4.5m fairing it road in).  On something like starship, they could make the mirror probably 2x as large across the diameter...or cut costs by not having to build a mechanism that will have to fold out to such a high level of precision.

 

In regards to the moon stuff, it's not necessarily as important except to get enough mass to the moon.  The Saturn V with the Apollo missions on managed to ~15 metric tons of material.  The Starship even conservatively will be able to bring 50 tons (but more likely 100 tons).  That means you don't have to worry as much about scientific equipment and such.  Then you have to consider the size of things...have you seen how the astronaughts had to sleep in the Apollo lander.  The space they had to live in was 160 cubic feet...they literally had to sleep in hammocks overtop of each other and slightly propped up.  If you include the entirety of it, it's only 218 cubic feet (6.2 cubic meters).  So imagine a 1.85m x 1.85m x 1.85m area (Think that an average human is 1.7m).  That does not make any sustained mission really easy.

 

In all of the Apollo missions, they managed to bring back less than  500 kg of samples (that's cumulative)...the Starship will be able to bring back maybe even more than a ton of material from the moon which would be huge in terms of no longer needing to be as conservative to samples.

 

As well, eventually the trip to mars they will need to land an unmanned vessel to pick up all the samples for analysis for signs of life.  With Starship that makes it a whole lot more plausible.  Actually with the amount of mass the Starship might be able to bring, they might be able to actually land a proper sized test facility onto Mars to do the testing instead.

 

To clarify as well, you have the following rockets with SpaceX

Falcon 9; the workhorse

Falcon heavy; for loads that are too heavy or need to be put into further orbits/escape the Earth.

Starship

Both Falcons are stuck with a fairing size of 5.2m diameter.  For the majority of missions, the fairing size is actually whats the limiter not the actual payload weight.

Starship should have a 9m fairing, with a great chance of being able to add a larger fairing onto it.

 

Falcon 9 actually was designed to the be size it was so that they could ship the rockets back without the need for the super sized type of classification they would need on the roadways (i.e. Falcon 9 was designed with limitations in mind for cost cutting).

 

Starship, when successful, because it will eventually be successful, should cut the cost down of launching to about the same as they are currently charging for a Falcon heavy (at least rumored of what they are charging).  While it might not necesarily be cheaper per launch than a Falcon 9, it will be able to be used to deploy more satellites at once (and the key larger satellites) which actually could lower the cost of launching per sat down by quite a bit.

 

The Starlink V2/V3 sats are actually a good example of this, you can't realistically fit them on the Falcon 9...like I mean you could, but it's not economical that way.  And those V2/V3 sats are the ones that will allow for cell to sat (and make it backwards compatible without the need for special hardware)

[CarlBar]

8 hours ago, Kisai said:

Computers are at a scale now that you should not need to "blow things up on the pad", if you're blowing stuff up on the pad, you've cut too many corners.

 

Computers are not at that scale, not even close. Any large simulation you run today will have a whole host of assumptions baked in that let them run large parts of it using very simplified rules to ease the computational burden. Simulations are only very precise where the people who built the simulation believe it needs to be. The problem is the more out on the extreme edge of what we can currently do you get, the harder it becomes to know where to be precise and you've got a fair degree of guesswork in there, educated guesswork, but it's still got a big uncertainty factor attached.

 

Thats not to say you can't do it all before you build somthing, but doing so is seriously expensive and time consuming. Which is why SpaceX has gone the route they have. It's significantly cheaper to do it this way.

 

As an aside NASA has done this in the past. Aside from projects like their Hypersonics research which involved a lot of single use parts the most obvious example is the  landing procedure for the Space Shuttle. When they built it they couldn't fully simulate the final runway landing and had to resort to literally dropping a shuttle from altitude using another aircraft and having pilots land it to figure a lot of the details out. They used the pilots experiences and the data from the recorder to write an official procedure after the fact.

 

Today thats something we can mostly avoid for this type of scenario, (though airliners still tend to need occasional updates to the design due to a combination of circumstances they didn't account for cropping up in actual use and causing issues. See the miracle on the Hudson for a set of circumstance where the checklists and SOP didn't line up well. Check the video Mentor Pilot did on youtube about it if you want specifics). But there's still things further out on the extreme edge we can't simulate. A lot of NASA's non-rocketry R&D is involved in doing scale model tests in these areas to give them a basis for future simulations.

 

55 minutes ago, Mark Kaine said:

i agree, space exploration is important... i was just questioning the specific purpose of heavy lifters, especially new ones... especially with "crew"... is falcon heavy (that's how its called right?) really going to be that much cheaper... but then he wants to go to mars, instead of io or europa, etc.?

 

As mentioned The new one is Starship. "The Starship" refers to the second stage, and "The Booster" when used in connection refers to the first stage.

 

Also even if Starship ends up costing twice their estimates it's going to drop the price to orbit more than four time compared to Falcon 9, (assuming i'm remembering the numbers right). And Falcon 9 has cratered the cost to orbit allready, if it wasn't for government support almost every other launch provider would be out of business, most can't come close on cost.

 

And Falcon 9's cratering of costs is allready leading to an uptick in people putting things in orbit, before they could never have considered it due to cost and as a result new things are being done. There's a whole bunch of people trying to get startups going to investigate zero-g manufacturing techniques for various things, (a pharmaceutical startup group has even got a satellite launched to see if the theory on it checks out, they're having trouble getting permission to land the samples though). ASteroid and other body mining has been talked about for a long time and would become plausible with somthing like Starship.

 

And a lot of the time pure science leads to new discoveries that then result in new technologies as a side product. NASA has pioneered the development of new alloys over the last several decades that have gone into commercial use, or are being investigated for that. And of course there's solar power generation that can be done up there, unlimited green energy in theory.

 

And as for Io, Jupiters Van Allen belts are a far bigger concern, they'll give you a lethal dose in very short order anywhere inside the orbits of the first 4 moons.

[Kisai]

3 hours ago, CarlBar said:

 

Computers are not at that scale, not even close. Any large simulation you run today will have a whole host of assumptions baked in that let them run large parts of it using very simplified rules to ease the computational burden. Simulations are only very precise where the people who built the simulation believe it needs to be. The problem is the more out on the extreme edge of what we can currently do you get, the harder it becomes to know where to be precise and you've got a fair degree of guesswork in there, educated guesswork, but it's still got a big uncertainty factor attached.

 

Thats not to say you can't do it all before you build somthing, but doing so is seriously expensive and time consuming. Which is why SpaceX has gone the route they have. It's significantly cheaper to do it this way.

 

Nah , I disagree. I think there is sufficient computational power to simulate or use AI to test a billion permutations of variables that nothing should be exploding while it still remains within earth's gravity well. When things start being sent beyond the moon, then we no longer have sufficient data to simulate things.

 

Remember this image that floats up from time to time?

That's Margaret Hamilton next to the apollo project software she and her team wrote.

 

This is back when software had to be engineered and tested before the thing was built, in a time before software engineering was a thing.

 

You would think the apollo computers, which were about as powerful as an Apple II, would be outclassed quite substantially by now. You can even emulate it (It's about 3MB.)

 

If your only argument is "It's too expensive" / "it would be cheaper to destructively blow stuff up multiple times rather than build it correctly fewer times, you actually get a lot more bang for the buck from more simulations, and it makes people a lot less mad about wasting materials and contaminating the environment/orbital space.

 

You build it only after there is nothing left you could simulate (eg simulation cost becomes infinite), you see this in AI training, where you could potentially run training indefinitely but the improvements between X and X+time along the time axis get exponentially farther apart, or even start ticking backwards and losing accuracy.

 

Anyway, the point I'm making here is that every explosion by a space craft, manned or not, contributes to negative sentiment towards the country that launched it. China blew up that one satellite in 2007 and added like 10,000 of the fragments to what's in orbit, there's 500,000 fragments of space debris already. Two events after that, also contributed as much junk into orbit as well.

 

 

[Uttamattamakin]

On 11/20/2023 at 12:26 AM, wanderingfool2 said:

Except that it managed to essentially do what they were hoping to do in the TEST.

You're right I won't believe My Lying Eyes and will instead believe the SpaceX statement that I quoted into the original post.  Everything was successful this test was wonderful it even successfully blew itself to Kingdom Come when it was underperforming.

 

Being serious note from that statement even SpaceX admits they didn't command the booster to blow up it just blew up by itself.

 

Let me put it to you this way getting this thing into space with the design it has is just the first challenge.  Second issue is the heat shield technology they've gone for with Starship and the way they want to have it land.  As I recall when they were still testing Starship having it make short Hops and then land it never landed without eventually blowing up. 

[manikyath]

17 hours ago, Kisai said:

simulate or use AI to test a billion permutations of variables

we're already talking significant segment of supercomputer time for one simulation, this isnt some "numbercrunchign" problem, we're talking "simulating gas molecules" level of simulation to make it accurate enough that it makes sense to do over a real-world test.

 

17 hours ago, Kisai said:

 

That's Margaret Hamilton next to the apollo project software she and her team wrote.

 

This is back when software had to be engineered and tested before the thing was built, in a time before software engineering was a thing.

 

You would think the apollo computers, which were about as powerful as an Apple II, would be outclassed quite substantially by now. You can even emulate it (It's about 3MB.)

that's also a vastly different task than what we are discussing when we say "simulating a launch". the apollo computer was brilliant in it's simplicity, but also didnt do anything even close to simulating any sort of real world scenario. it was basicly a glorified fly-by-wire system, fed with enough tracking data that it had a solid enough idea of where it was.

 

17 hours ago, Kisai said:

you actually get a lot more bang for the buck from more simulations

the reason SpaceX is blowing stuff up, is *BECAUSE IT IS CHEAPER* than simulating, at the specific points of the development where they decide to bloww stuff up. sure they do plenty of simulations before they get there, but simulations have diminishing returns, because everything they did on paper (on a computer..) said that on test 1 the concrete should have held up.

 

17 hours ago, Kisai said:

You build it only after there is nothing left you could simulate (eg simulation cost becomes infinite)

you build it when the cost-benefit of a prototype is better than the cost-benefit of a simulation.

cost-benefit ofcourse being a very different sort of calculation to different organizations.. for NASA the public image of blowing up a prototype is a big impact on financing, so they spend more on simulating, but for SpaceX which largely operates on private funding this image problem is less important, as long as development targets are being met. which afaik so far they are.

 

4 hours ago, Uttamattamakin said:

ou're right I won't believe My Lying Eyes and will instead believe the SpaceX statement that I quoted into the original post.  Everything was successful this test was wonderful it even successfully blew itself to Kingdom Come when it was underperforming.

the booster performed (from what we know on the outside) as expected all the way past hot staging, and only encountered an issue when attempting the flip and boost-back burn. it is, essentially, proven to work as a single-use launch vehicle in the same way as SLS has been proven as a single-use launch vehicle. this is the extent to which SpaceX was *hoping* to get with this test, with the added bonus that they could try to land it if that all went well. next on the list is presumably figuring out what went wrong with the second stage (so far the most credible guess i've seen is that they simply missed their target), and figuring out what went wrong with re-light for the boost-back burn on the booster.

 

"success" means the problems of test 1 were overcome, and the "uphill ride" went as expected as far as we can see. yes, there was a plan for both stages to come back down *in case they made it up*, but that was -for now- optional. starship is a completely new platform (as opposed to SLS, which is largely based on previous NASA tech), so it's a process of crawling, then walking, then running, then jumping. ambitions are great, especially if you think that the nutcase at the top is talking in the present tense, but the actual engineers who are deciding to press the go button on the world's most powerful grain silo *actually* know what they're doing, and we're just a bunch of idiots on the internet making a fuss about it.

 

or in short; until *after* hot staging everything went well, so the primary goals of the mission were met, and data was gathered from which they can build further development.

 

5 hours ago, Uttamattamakin said:

As I recall when they were still testing Starship having it make short Hops and then land it never landed without eventually blowing up. 

you're about 2 years out of date on that one.. they did land on a super foggy day, so i presume it didnt receive that much fanfair because the camera views are horrid...

 

and just because numebers are fun, and wikipedia apparently has some listed...

- NASA's SLS is quoted to have approximately a $24 billion development cost, with estimated over $2 billion per launch

- piecing together some SpaceX quotes for how much money is going to boca chica ("starbase") - they should currently be around the mark of $5 billion spent. the big nutcase hopes and dreams of getting cost per launch down to $1 million, but even if they miss that mark by 500x, they're still significantly cheaper than NASA. case in point.. this test flight is the 9th booster they built, and the 25th starship they built. obviously most of those never flew, but they were built as at least partial prototypes.

[CarlBar]

17 hours ago, Kisai said:

Nah , I disagree. I think there is sufficient computational power to simulate or use AI to test a billion permutations of variables that nothing should be exploding while it still remains within earth's gravity well. When things start being sent beyond the moon, then we no longer have sufficient data to simulate things.

 

Remember this image that floats up from time to time?

That's Margaret Hamilton next to the apollo project software she and her team wrote.

 

This is back when software had to be engineered and tested before the thing was built, in a time before software engineering was a thing.

 

You would think the apollo computers, which were about as powerful as an Apple II, would be outclassed quite substantially by now. You can even emulate it (It's about 3MB.)

 

If your only argument is "It's too expensive" / "it would be cheaper to destructively blow stuff up multiple times rather than build it correctly fewer times, you actually get a lot more bang for the buck from more simulations, and it makes people a lot less mad about wasting materials and contaminating the environment/orbital space.

 

You build it only after there is nothing left you could simulate (eg simulation cost becomes infinite), you see this in AI training, where you could potentially run training indefinitely but the improvements between X and X+time along the time axis get exponentially farther apart, or even start ticking backwards and losing accuracy.

 

Anyway, the point I'm making here is that every explosion by a space craft, manned or not, contributes to negative sentiment towards the country that launched it. China blew up that one satellite in 2007 and added like 10,000 of the fragments to what's in orbit, there's 500,000 fragments of space debris already. Two events after that, also contributed as much junk into orbit as well.

 

 

 

If you'd ever read details about simulations you'd know about all the assumptions they have to make. Simulating things down to the tiniest detail is hugely difficult. NASA has some serious supercomputers to do it and they still can't get all the way there. NASA has had scale test model stuff go badly wrong and traced the flaw to effects their simulations didn't show.

 

As for the cost factor, i'll trust Space X to be able to do the math on which is cheaper. Hell the supercomputer aspect may be part of it, building or getting access to a computer that powerful is an expensive endeavour.

 

Funnily enough getting out to the moon or beyond doesn't actually make things any more difficult. The conditions are very similar between LEO and lunar orbit, some more radiation, but thats somthing scientists have experiance with from a verity of other probes.

 

I'm also not sure where your going with the PR angle. No one's complaining or upset about how this test went beyond people like you. World governments aren't kicking up a mes and neither is anyone else. The debris all fell in the pre-arranged and pre-cleared area's, which where pre-cleared for this specific purpose. The Chinese ASAT test had people hot and bothered both because no one really wants space to become a battleground, and because all the debris stayed up for an extended period of time. This wasn't military saber rattling and all of the material re-entered within hours at the latest.

 

3 hours ago, Uttamattamakin said:

You're right I won't believe My Lying Eyes and will instead believe the SpaceX statement that I quoted into the original post.  Everything was successful this test was wonderful it even successfully blew itself to Kingdom Come when it was underperforming.

 

Being serious note from that statement even SpaceX admits they didn't command the booster to blow up it just blew up by itself.

 

Let me put it to you this way getting this thing into space with the design it has is just the first challenge.  Second issue is the heat shield technology they've gone for with Starship and the way they want to have it land.  As I recall when they were still testing Starship having it make short Hops and then land it never landed without eventually blowing up. 

 

If you'd been paying attention to Space X before the test you'd know that getting through the hot staging was the primary goal. they've been stating that pretty much since they announced the move to hot staging month ago. Everything else for them was a bonus, they'd have liked to, and hoped to get other stuff done, but it wasn't the big step they needed to get done this flight.

 

Also just because Space X didn't specifically command  detonation doesn't mean it occurred randomly. The flight termination systems have a variety of parameters programmed into them that will make them activate without a command from the ground. This may well have met them, the explosion certainly originated from the location of the flight termination system so if they didn't command it, then it was probably a malfunction of the termination system. And thats not really on Space X as the design is approved and regulated by outside agencies. 

 

As for landing without blowing up. 11 flights, 2 where tethered such they never left the ground, 4 failed to land properly. The other 5 all made successful landings. One of those, (the final one), had a fire that started several minutes after the landing whilst they where still getting propellent out of the tanks so people could approach.