totm nov 2023 SpaceX Discussion Thread

[StrandedonEarth]

1 minute ago, JoeSchmuckatelli said:

When you start with the baseline expectation that it likely will blow up on the pad... This is more in the direction of success than failure. 

Still... Wasn't pretty. 

Nope, not pretty at all. Especially after learning the AFTS was supposed to fire sooner. I’d like to say more data gained, but since they say they lost comms, very little. 

[JoeSchmuckatelli]

44 minutes ago, StrandedonEarth said:

Nope, not pretty at all. Especially after learning the AFTS was supposed to fire sooner. I’d like to say more data gained, but since they say they lost comms, very little. 

Yeah, that surprised me as well. 

Whole Lotta ways that could have gone bad. 

[CBase]

okay let's try to wrap up community responses with what Elon said:

• Engine failures:
  • community/critics: too many, propably by pad damage, needs more testing
  • Elon: 3 at start was accepted, they were off limits, but we prefered to try over scrub. Later on we lost some due to heat shield problems. We have more than we can use right now.
• HPU / TVC:
  • community/critics: HPU exploded
  • Elon: no comment on HPU, but acknoledges some explosion and loss of TVC
  • side note: TVC is elevtric in most current design (not sure about build boosters)
• staging:
  • community/critics: too low, aero probs, seperation got stuck
  • Elon: wasn't safe enough to try without TVC, really something we want to get to on next attempt
• pad damage:
  • critics: huge failure, everybody should have known, SX will learn to build flame trench, like all previous generations did
  • Elon (older response): water cooled steal plate was not ready
  • Elon: high pressure, bending most likely cause for concrete failure. Was not expected, but damage is limited to 8 weeks work. Flame Trench is not needed
• regulations:
  • critics: environmental damage from conrete everywhere
  • Elon: sand distribution is no big deal, however FTS was not working as intended, communication breakdowns did happen
• structural:
  • community/critics: no more comments on using "ordinary" steal
  • Elon: working better than expected as observed by unintended stress at end of test
• money:
  • critics: wasting too much money
  • Elon: 2B/y is fine
• time:
  • critics: more thought and planing would safe time they now have to spend on cleaning up the mess
  • Elon: we learned at lot and will be the first to be ready for Artemis

Did I miss some important point ?

So personal I do think Elon is for good reason quite relaxed about the first test flight. Will he propably fail on reaching his ambitious mile stones ? yeah, but propably he will be right to be first one ready for Artemis. By years. Like with crewed ISS flights. Or reusable stages.

[magnemoe]

8 hours ago, kerbiloid said:

And fly around as concrete slabs, and cover the New Pompeii Port Isabel with dust.

Just as planned.

The smashed tanks are also looking as they should be.

I know, it was mostly to sticking back saying the rocket was not reusable. Blowing up the pad and stuff was not planned  

[kerbiloid]

Btw, why do they say that some engines were damaged by the pieces of concrete, rather than overheating?

Wouldn't the mechanically damaged nozzle go cracking and explode?

P.S.
Now they have a chance to test an Orion pusher plate by hammering it down on the next launch.

Btw, the diameter is similar.

[tater]

 

7 minutes ago, kerbiloid said:

Btw, why do they say that some engines were damaged by the pieces of concrete, rather than overheating?

They (SpaceX) don't say that. They think the engines were not in fact damaged by what Elon calls the "rock tornado" in the audio above, though he says that it is not impossible that damage was incurred.

 

Bottom line is that they will sort it out I think. Better to blow up a bunch of Starships than be using Falcon 9 and Dragon decades from now. That would be an epic failure, to use the same smallish rocket for years vs going to the next level. I've been waiting for my science fiction future since I was a kid. At the time I'd say an Arthur C. Clarke future (my fave as a kid)... but then Shuttle hung around for 30 years doing... nothing.

To be clear, I thought (and think) Shuttle was a cool vehicle... amazing. But the Shuttle era was a lost opportunity. A failure to innovate once it was flying.

[Deddly]

3 hours ago, JoeSchmuckatelli said:

Wasn't pretty. 

It absolutely was pretty. It was an astoundingly beautiful fireball and anyone who says otherwise hasn't been playing enough KSP lately. 

[magnemoe]

1 minute ago, tater said:

They (SpaceX) don't say that. They think the engines were not in fact damaged by what Elon calls the "rock tornado" in the audio above, though he says that it is not impossible that damage was incurred.

Bottom line is that they will sort it out I think. Better to blow up a bunch of Starships than be using Falcon 9 and Dragon decades from now. That would be an epic failure, to use the same smallish rocket for years vs going to the next level. I've been waiting for my science fiction future since I was a kid. At the time I'd say an Arthur C. Clarke future (my fave as a kid)... but then Shuttle hung around for 30 years doing... nothing.

Engines outside the first 3 failed 20+ seconds after launch. Now this could be because they took damage from  rocks who caused them to overheat later on. 
Now superheavy bottom had the benefit of having an rocket flame downward so powerful that it destroyed concrete, have fun getting an rock up to the engines. 
Then the first row of engines starting up probably, but not at liftoff. 

And agree, they probably have an solid plan trying to catch superheavy, but they probably want an second tower for that. 
But I can not see an solid plan for Starship recovery. Boca chica has the issue of they having to overfly Mexico for most orbits. Yes you have the cape, but you still has to overfly densely populated areas. 
Overfly as in below karman line or stuff will rain down if it breaks up in atmosphere. 

[JoeSchmuckatelli]

2 hours ago, CBase said:

We have more than we can use right now.

This was in relation to slowing down production = they have plenty on hand for the next few flights of testing.

2 minutes ago, Deddly said:

It absolutely was pretty. It was an astoundingly beautiful fireball...

You know... I'm actually with you.  It was amazing to see that much tonnage fly.   The boom was a good boom - for a boom.

 

That said - there were so many little things that went wrong, and the cascade of how they went wrong meant we did not get to see what I had hoped for: a clean separation and some kind of boost-back hover attempt in the Gulf & some kind of splash or (hopefully hover attempt) in the Pacific.  The main thing I did not expect was all the damage at Stage 0.  Kerbiloid's comment above struck my funny bone!

5 minutes ago, Deddly said:

hasn't been playing enough KSP lately. 

Yeah - on that...  This is all KSP2 lets me see:

 

[Deddly]

8 minutes ago, magnemoe said:

they probably have an solid plan trying to catch superheavy,

Umm... a thought... why not launch it directly from the "chopsticks", high off the ground, with no launch pad at all? The best part is no part and all that... 

[CatastrophicFailure]

1 minute ago, Deddly said:

Umm... a thought... why not launch it directly from the "chopsticks", high off the ground, with no launch pad at all? The best part is no part and all that... 

They can’t hold that much weight. They’re designed to lift and empty Superheavy, and just that is some serious engineering. Fully fueled you’re talking many thousands of tonnes.

[tater]

10 minutes ago, magnemoe said:

Engines outside the first 3 failed 20+ seconds after launch. Now this could be because they took damage from  rocks who caused them to overheat later on. 
Now superheavy bottom had the benefit of having an rocket flame downward so powerful that it destroyed concrete, have fun getting an rock up to the engines. 
Then the first row of engines starting up probably, but not at liftoff. 

I was specifically replying to the claim that "they say" engines were damaged by concrete/rocks (FOD). While that is possible, SpaceX says they do not think so (in audio above). People can make all the claims they like, the the hypothesis is reasonable, but SpaxceX apparently thinks otherwise right now.

 

10 minutes ago, magnemoe said:

And agree, they probably have an solid plan trying to catch superheavy, but they probably want an second tower for that. 

I never mentioned catching SH. First they have to get it all working, then they have to land it precisely in the water a number of times (including a wet (lol) dress rehearsal hovering the right height above the sea, etc. Only then could they try a catch.

 

10 minutes ago, magnemoe said:

But I can not see an solid plan for Starship recovery. Boca chica has the issue of they having to overfly Mexico for most orbits. Yes you have the cape, but you still has to overfly densely populated areas. 
Overfly as in below karman line or stuff will rain down if it breaks up in atmosphere. 

I think catching SS is a long-pole item. I would honestly expect legs before that as initial testing.

[Deddly]

48 minutes ago, CatastrophicFailure said:

They can’t hold that much weight. They’re designed to lift and empty Superheavy, and just that is some serious engineering. Fully fueled you’re talking many thousands of tonnes.

Moar struts?

Seriously though, how much weight do the chopsticks have to be capable of holding, assuming the inertia of that returning booster? I'm thinking it's probably the strength of the fins that is the limiting factor

[tater]

16 minutes ago, Deddly said:

Moar struts?

Seriously though, how much weight do the chopsticks have to be capable of holding, assuming the inertia of that returning booster? I'm thinking it's probably the strength of the fins that is the limiting factor

The booster might be ~200 tons. The stacked rocket is ~5000 tons.

At the time of the catch the booster would basically be hovering.

 

 

 

Started listening again. He said he expects 4-5 flights this year. So They seem bullish on getting the pad back in shape.

They have more Raptors now than they need, so they are working on improvements (reliability, and performance).

"A couple billion this year" on Starship. No need for new funding.

The launch ring had minimal damage. Tower is fine.

The vertical tanks were going to be replaced anyway. I had read before that they were not in fact allowed to use their own tanks for CH4 per regulations already in place, hence the "hot dog" commercial tanks for that. I looked those up ages ago, and they are incredibly cheap (~$20-25k). Cheap in the sense that if SpaceX even thought about making their own, the cost of Starship tankage must be trivial.

Edited April 30, 2023 by tater

[darthgently]

1 hour ago, JoeSchmuckatelli said:

That said - there were so many little things that went wrong, and the cascade of how they went wrong meant we did not get to see what I had hoped for: a clean separation and some kind of boost-back hover attempt in the Gulf & some kind of splash or (hopefully hover attempt) in the Pacific.  The main thing I did not expect was all the damage at Stage 0.  Kerbiloid's comment above struck my funny bone!

Occam's razor hunch:

1) They wanted to get data on several processes

2) They had a booster and engines that were already superceded by newer approaches but would be fine for collecting 70% of the data they are currently seeking

3) They are tired of scrapping stuff.  They want to fly something

4) Give the people what they want; excitement

5) 4/20

 

[Nuke]

5 hours ago, kerbiloid said:

Btw, why do they say that some engines were damaged by the pieces of concrete, rather than overheating?

Wouldn't the mechanically damaged nozzle go cracking and explode?

P.S.
Now they have a chance to test an Orion pusher plate by hammering it down on the next launch.

Btw, the diameter is similar.

boom boom starship should totally be a thing.

[Ultim32]

T-5 minutes to launch

 

And liftoff

[Geonovast]

Sad to watch, but was also really cool.

This is probably obvious to some of you, but does anyone know what the two white dots that went across the screen right after BECO were? T+3:43 and T+3:53.

[cubinator]

32 minutes ago, Geonovast said:

Sad to watch, but was also really cool.

This is probably obvious to some of you, but does anyone know what the two white dots that went across the screen right after BECO were? T+3:43 and T+3:53.

First one is a star, second one is a satellite.

[bigyihsuan]

On 4/29/2023 at 7:48 PM, RCgothic said:

Read the whole of this thread:

Unrolled: https://threadreaderapp.com/thread/1652451971410935808.html

[tater]

 

[sevenperforce]

One of the cool things about the FH launch last night -- if you watch SES-3, it actually shows the velocity decreasing as the burn begins. That's because speed was being measured relative to the ground station in a geocentric coordinate system.

[Brotoro]

1 hour ago, sevenperforce said:

One of the cool things about the FH launch last night -- if you watch SES-3, it actually shows the velocity decreasing as the burn begins. That's because speed was being measured relative to the ground station in a geocentric coordinate system.

Ah! I didn't catch the SES-3 burn itself. When I checked back in they were releasing the satellites, and the velocity reading at that time looked way too low (I thought the display or units must be faulty). But geocentric coordinates with velocity relative to surface makes it all clear. Thanks!

Edited May 1, 2023 by Brotoro

[Minmus Taster]

Hate to be that guy but what exactly is "TVC"?

[SunlitZelkova]

1 minute ago, Minmus Taster said:

Hate to be that guy but what exactly is "TVC"?

Thrust vector control?