totm nov 2023 SpaceX Discussion Thread

[Flavio hc16]

https://jamestemplephotography.pixieset.com/spacexstarship7explosion2025-phonewallpaper/?fbclid=PAY2xjawH665dleHRuA2FlbQIxMQABpoWZuh2n_h0tNEFWyhEdbi7o3TNJ0g-4EC4dC4BN4ZriFbWTrq8IXjyOnw_aem_xWCgVWX0mUY61lM243q_hA

 

If someone wants some amazing wallpapers/prints of the flight 7 breakup

[Ultimate Steve]

19 minutes ago, Exoscientist said:

What’s the scuttlebutt on Discord and on Forum.NasaSpaceflight.com about the origin point of the leaks in the Starship in the last flight, the engines or the plumbing?

Everything about a potential failure cause in the NSF flight 7 discussion thread  (https://forum.nasaspaceflight.com/index.php?topic=61945.480) from around page 8 until Elon tweeted about the suspected root cause:

Spoiler

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My early complete speculation would be that, as the acceleration built up towards the end of the burn, the structural integrity may have been lost due to the panel that was visibly loose during the ascent. Not quite sure if that would tie in with the observed shutdown of the engines however...

 

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They have some sort of adapter to fit Raptor 2 fuel lines to Ship V2, right? I wonder if that was the source of the failure. Either that or the loose panel visible on ascent would be my (uninformed) bet.

 

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Or maybe structural failure of the methane transfer tube as it was inevitably modified from the previous ship version. There was a sudden rapid drop of methane amount on the telemetry, which suggests a leak and engines dying one by one is then either a fire making rounds or prop starvation. And yes, speculation.

 

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Methane level drop started around the time of engine cutoff, could also have just been the result of an uncontained engine failure severing prop lines.

 

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During the last seconds of stage 2 telemetry in SpaceX's webcast, from T+07:39 to T+08:27, the LOX and CH4 meters for stage 2 went from being roughly balanced to massively imbalanced with the LOX at loss of telemetry showing ~12% and the CH4 ~5%. That imbalance would cause a massive performance loss so it can't be nominal. This suggests that whatever went wrong didn't happen instantly, so there should be clues in the full telemetry for SpaceX to diagnose the issue.

 

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Thought: I'm wondering if there was a loss of hydraulic power to the gimbals. The graphic showed the ship pitching up under the asymmetric thrust when half the engines went out. At that point, there was only one engine capable of gimbaling remaining.

Question for those who would know: is the amount of pitch-up we saw consistent with that engine's gimbaling working?

 

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quick prediction:  the first engine going dark was a failure.  The failure caused a methane leak and the others are shutdown due to lack of propellant.  Can't meet trajectory cone requirements -> fired FTS.

 

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Quick prediction: Obvious electrical short in wiring to flap drive, as seen on video, caused a cascade series of electrical faults resulting in loss of critical control components.  This could include engine controllers and/or propellant pressure control.

 

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In the run up to the launch SpaceX said they were testing active cooling on some tiles. I wonder if that set up failed in some way?

Everything in the NSF flight 7 discussion thread after Elon tweeted about the suspected root cause, through like halfway ish through page 25, which is the current end of the thread as I write this:

Spoiler

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The propellant feed system was completely new and that's what seems to have failed

 

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it's not clear from this statement whether the leak developed after launch or was known about but deemed manageable. The "vent capacity" and "fire suppression" might be clues. He's ranted about flanges and leaked in the past, so maybe they're resigned to living with leaks. Leaks took out  SN4 and blew the aero covers off on flight 5, I think.

 

Then there was a big tangent about whether or not they were going to press on without knowing the root cause, here are some vaguely related snippets:

 

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Part of the rationale for the Raptor 3 design was to minimize relative fragile plumbing and eliminate the need for shielding.  To some degree V2 is already outdated, but they have quite a few to use up and V3 is still on the test stand.

Stop gaps like additional suppression and venting seem like a reasonable solution to avoid spending too much time on what is an outdated design.  Or maybe they will still be useful who knows?

FAA investigations aren’t punishments for failure.  If they can identify a cause, address them, and document everything then they can proceed.  Seems like they have quite a lot of data to use

 

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Please forgive me, but I'm going to do some wild speculation here;

*IF*, as some interpretations of Musk's tweet claim, SpaceX is going to press ahead without fully understanding the root cause, I'm wondering if the reason is that they lack adequate data for the failure to be fully certain, and so decided that the most cost and time effective way forward is to refly with some extra instrumentation, plus extra venting, in the suspect area? 

And, further speculation from me: SpaceX being SpaceX, initial statements and plans might well be revised if they do discern the root cause in the meantime.

 

But then SpaceX tweeted that they were going to review the data to better understand the root cause, putting a stop to that discussion but there were a few interesting closing statements:

 

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I think this pretty much settles the “will they investigate” question. 

My interpretation of the Musk post was that he was simply trying to throw us amazing people here at NSF a bone, along the lines of “this is what I know from a quick 10 minute review of the data.”

 

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Fuels leaks suck. They learned they need to mitigate against them because they're going to happen, apparently, given the requirement of rapid assembly and re-use.

 

And back to speculation:

 

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Maybe because they already have a fix a it od called Raptor 3? I've read, that with the new version the leaks should by the thing of past.

 

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How about deal with the cause by eliminating or reducing the leaks vs dealing with the effects.

(In response to a discussion about the heat shield):

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On this, I would agree, that's the signature problem.  And, so long as that's where they're failing, it makes sense.  If it turns out that some of the piping to provide transpirational cooling to demo tiles broke, well, that makes sense.  I'm not sure that's the kind of error that we're looking at here (I don't even know if they flew any such thing). 

 

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The return of propellant leaks in the second stage is a concern. It seems like they redesigned the plumbing in order to fix the leak problem and that fix completely failed. That could mean that they did not correctly identify the cause of the problem, or that it may be a very difficult problem to fix.

 

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I think the leak happened sometime after launch.  There's no way it would have been found without (b) being 5x slower than the present pace.

My guess is the leak isn't something you "look for" before launch.  They already do that.  It's probably something like sympathetic vibration that can only be found by testing in flight or extremely extensive month->year long simulations of hardware at a macro level

Question is, did they instrument the area well enough to detect something like excess vibrations?

 

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What has not been adressed yet is that this was the first flight that was NOT using Raptor 2 - it was using Raptor 2.5.

(2.5 is a Raptor 2 refitted with the connection hardpoints to connect to a V3 mount on Ship)

This is a completely unknown variable compared to Ship 1 / Raptor 2 that very well might have been the main issue at hand.

(Just armchair speculating of course, IANARE)

A late response to the "mitigate or solve" debate:

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It's not like they don't care about the leaks, but if finding the root cause or the fixes takes too long, it's perfectly ok to postpone that to later flights, because the pez dispenser and heat shield teams are waiting for the test result. And if the internet rumors are correct that they intend to tow the landed ship back to Australia, that would help immensely with finding any leaks, just another thing SpaceX will take into account when making a decision regarding the leaks.

This is not even a new space thing, because NASA did pretty much the same thing with Artemis II for the Orion heat shield issue: they did find root cause, but chose to not to fix it, instead opt for a workaround. And that one is a crewed mission.

 

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The visible boom is the propellant tanks ripping apart from the internal pressure. The question is, what caused the propellant tanks to rupture?

- One possibility is that the FTS charges detonated, ripping the tanks open and releasing their pressure.
- Another possibility is that the tanks failed after the Starship started reentrering, and the metal tanks were heated to structural failure.
- A third possibility is that there was some malfunction on the stage due to damage sustained previously. For instance, a valve could have failed, dumping high pressure gas into the propellant tanks and causing them to fail due to over-pressurization.
- I'm sure there is a number of other possibilites.

Personally, I think it was a failure due to reentry heating.
 

 

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If there was an uncontrolled massive leak of CH4 as the telemetry indicated, maybe the pressure in the tank got too low and the common bulkhead inverted itself due to pressure differential with the LOX tank.

 

This one is really interesting:

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Quote below from user DutchSatellites on X at:

https://x.com/DutchSatellites/status/1880649008366203311?t=KIIQz7pLH83jmlea2co_hw&s=19

[The leak happened in the (relatively) low-pressure plumbing between the tank & the propellant inlets of the Raptors. Working pressure in that plumbing is below 10 bar. The 'super high pressures' aspect of Raptor applies to the internal plumbing of the engines itself.]

From Twitter beneath that he admits that it is from a private source at SpaceX:

And that's the last relevant post on this thread.

 

It seems to be a lot of speculation with the same amount of information as we have and a little more competence than we have, except for possibly some new information from the tweets from @DutchSatellites on Twitter/X . I am not sure how qualified this guy is. Scrolled back a little and didn't really come to any solid conclusions and I've already scrolled enough today.

I asked on one of the spaceflight-adjacent Discord servers I am a part of if they had heard anything similar, or if they thought this guy was credible, and one person thus far has responded saying that this guy is usually credible but has no idea about this specific piece of information.

1 hour ago, Exoscientist said:

There is no doubt that SpaceX knows the origin of the leaks.

It hasn't even been four days. I also expect that they at least know the general area (and possibly the exact area) by now but I wouldn't go as far to say that there is no doubt.

 

1 hour ago, Exoscientist said:

During the prior tests of the Starship landing procedures there were cameras in the engine bay that were able to image leaks when they occurred:

(snip)

There is no doubt such cameras are still in the engine bay during the Superheavy/Starship test flights.

Again with the whole "No doubt" thing. Maybe this is a me thing but I'm rarely so certain about anything. Have a little imagination.

It isn't quite that cut and dry, during the suborbital test campaign the engine section looked like this:

And in this configuration they were able to get this sort of camera view:

I can't find any good and easily accessible pictures of the new arrangement besides this image from integrated flight test 1, but to my knowledge, the shielding they added is still present on the current generation of vehicles (someone I know recently affirmed this for my recent gimbal calculations), though I could be wrong:

The existence of an enclosed space (between this shielding and the tank dome) tracks with the whole thing about an overpressure due to not enough venting causing all engines to fail (which I don't see a reasonable path towards occurring if there was no enclosed space enclosing plumbing related to each of the engines).

Notably neither of these camera views are thought to still be available. The first one because the shielding blocks the view, the second one because the addition of the hot stage ring blocks the view (not that it would help much for anything besides stage separation and the couple seconds afterwards).

This is the only camera angle in the engine bay that (at least one of) the Starships in the orbital test is/are confirmed to have (in space relight on flight 6):

Which is quite lower in order to be able to peek through the shielding, and as such does not have as good of a view of the engine bay as the cameras did during the suborbital test campaign.

They (nearly) certainly have camera angles we do not know about but we do not know how many if any are inside the engine bay, or above the engine shielding. Notably with those sea level Raptors in their own cubbies, it might be pretty difficult to image those engines at all, even from cameras inside the engine bay, unless you had like 6 cameras looking down into the cubbies, 2 per engine, along with internal lighting. And then more cameras for the rest of the engine bay. And who knows, they might have done that.

Granted, they (nearly) doubtless have loads of sensors that aren't cameras over every inch (every square inch is hyperbole but you get the point) of the vehicle. But we do not know for certain that they have the same cut and dry visual confirmation that they had during the suborbital test campaign.

1 hour ago, Exoscientist said:

The Raptors should not be still leaking fuel and catching fire this late in their development.

They should not, and the current likely cause is in the new plumbing. We do not currently know the source of the leak for sure but we do know (unless of course SpaceX are lying to us in their official statements):

• The fuel feedlines for the vacuum Raptors were completely redesigned this flight
• The fuel feedlines (unclear if this is just Raptor Vacuum or also Sea Level Raptor) were redesigned to add vacuum jacketing

And we have the following things that might have happened but I don't currently have hard evidence for:

• A lot was redesigned for Starship V2, additional propellant feed system tweaks are likely
• Starship V2 might be designed with Raptor V3 in mind, something on the vehicle side or the engine side might have to be done to "Adapt" the Raptor 2s to a ship expecting Raptor 3s if the interfaces of R2 and R3 are not identical.
• Guy on Twitter/X alleges that private insider sources say that it was the propellant lines

A lot of direct and circumstantial evidence that the fuel feed system has a large percentage of new components. Raptor on the other hand, maybe they modified it a bit to adapt to the new fittings (which may or may not exist) (and they could (and IMO they would likely) have modified the vehicle instead of the engines). Apart from that, they are the same Raptors we have seen on previous flights - If they have leaked it wasn't major enough to get a mention in any report, and wasn't major enough to cause anything visually wrong with at a minimum flights 5 and 6.

Again, we do not know for sure where the leak was, but there are many reasons why suspicion currently resides with the propellant feed system and not the engines.

If it was the engines, then yeah, they've got to fix that. In that case, it is a good thing they're deep into development of Raptor 3 which, among other things, is designed to replace a large number of bolted joints (and therefore possible leak sources) with single parts, internal channels, and welded joints.

 

Also like.

This whole time I had assumed you were replying to other comments I had made about Raptor but I double checked after writing the above (though before the proofread and some edits) and you actually replied to my cost-per-flight comment that was unrelated to Raptor that I had posted 1. because I actually encountered someone claiming 389m per flight (though I now must say that I misinterpreted his words, he was stating that cost per kg parity with Falcon was likely to happen but anything beyond that was unpredictable, apologies for the public slander Anthonator00) and 2. in a (vain) attempt to disarm the quite heated political conversation that was going on at the time.

While I will give you the benefit of the doubt - It is quite possible that enough of the political stuff got deleted, for you to go - "Steve tried to change the subject away from the leaks!" and tried to get me back on topic - You are not beating the "Tries to shove Raptor reliability conspiracies into every single conversation no matter how related or unrelated it is" allegations.

"Hey, what's with all the politics, how about a nice conversation about approximate launch cos-"

"HEY what if Raptor is leaking? What if people are talking about it leaking? It leaked before, they know what caused the leaks and they aren't telling us!"

Is a little bit of an exaggeration but it adequately summarizes what I feel.

 

If this continues I'm just going to stop replying. Right now I think the value of my analyses to the others in this thread outweighs the pain of feeling like I'm banging my head up against a brick wall every time you take 5 minutes to pose (often flawed) arguments that take 2 hours to deconstruct. But it is getting very close. Don't ask me what the NSF scuttlebutt is. It is right there. One google away. Go look at it yourself.

[Exoscientist]

22 hours ago, Ultimate Steve said:

...

This whole time I had assumed you were replying to other comments I had made about Raptor but I double checked after writing the above (though before the proofread and some edits) and you actually replied to my cost-per-flight comment that was unrelated to Raptor that I had posted 1. because I actually encountered someone claiming 389m per flight (though I now must say that I misinterpreted his words, he was stating that cost per kg parity with Falcon was likely to happen but anything beyond that was unpredictable, apologies for the public slander Anthonator00) and 2. in a (vain) attempt to disarm the quite heated political conversation that was going on at the time.

While I will give you the benefit of the doubt - It is quite possible that enough of the political stuff got deleted, for you to go - "Steve tried to change the subject away from the leaks!" and tried to get me back on topic - You are not beating the "Tries to shove Raptor reliability conspiracies into every single conversation no matter how related or unrelated it is" allegations.

"Hey, what's with all the politics, how about a nice conversation about approximate launch cos-"

"HEY what if Raptor is leaking? What if people are talking about it leaking? It leaked before, they know what caused the leaks and they aren't telling us!"

Is a little bit of an exaggeration but it adequately summarizes what I feel.

…

There was no other reason for responding to this specific post of yours than you mentioned Discord. So I wanted to find out if that question was discussed on there. I don’t know which specific Discord forum this is. It wasn’t related to the cost issues.

 I’d like SpaceX to release those engines views it has available during the Starship engine firing, not just before, that clearly would be important for diagnosing the origin of the leak.

   Bob Clark

Edited January 21 by Exoscientist
Typos.

[tater]

SpaceX clearly doesn't care about leaks and wants to blow up tens of millions of dollars worth of spacecraft every mission for the LULZ. It's a deep conspiracy, and they will actively try to hide what they are doing from all the Smart People™ on the internet who are not the dupes of the conspiracy so they can successfully blow up rockets.

[tater]

 

[Exoscientist]

4 hours ago, tater said:

SpaceX clearly doesn't care about leaks and wants to blow up tens of millions of dollars worth of spacecraft every mission for the LULZ. It's a deep conspiracy, and they will actively try to hide what they are doing from all the Smart People™ on the internet who are not the dupes of the conspiracy so they can successfully blow up rockets.

 

 I would say SpaceX doesn’t want to release images damaging to the idea the Raptors are reliable. For instance it still it did not release images of what happened at the end of the ocean touchdown of the booster IFT-4, when it was clear it exploded. And it has not said anything about the Raptor that exploded on the booster during the IFT-4 landing burn.  

 It could dispel concerns the Raptor is still leaking and catching fire by releasing engine bay views of the booster and ship while the engines are firing, most specifically during the booster landing burns and the ship burns in this last flight.

 By the way, that Elon is apparently so sanguine about fires appearing in the engines bay in Starship raises questions if it is indeed the case fires arise in the engine bay during the booster landing, but SpaceX doesn’t care because they are “controlled”, so far.

  Bob Clark

Edited January 20 by Exoscientist
Added Elon twit suggesting that rather than ending Starship leaks and fires in the engine bay, they’ll simply control them.

[Nuke]

12 hours ago, JoeSchmuckatelli said:

I chimed in earlier about expendable second stage.  To me, Booster is ready for action as a heavy lift platform - but we need a second stage that can deploy stuff to space.  Starship is designed for landing on Mars, the Moon or Earth once complete.  But it doesn't look like the optimal platform for getting something really cool like a ridiculously large telescope.  That would need a TradSpace solution, IMO.

I really, really want to see some kind of major science package (Cosmology, rather than solar-system-planetary) get off the ground and out in the void, Sciencing.

Webb took way too long to get off the ground - and seeing as how lift has changed - we could really lean into the ridonkulous! 

like scale the eht to have an aperture the size of the solar system. begin the space telescope spam. then you can start selling time on major space telescopes to amateur astronomers. i also like the idea of the shotgun flyby mission for distant objects. maximize chance of success and data collection.

Edited January 20 by Nuke

[Nuke]

i kind of doubt an engine failure, because the cascade failure would have been faster and a lot more dynamic. engines blinking out one by one indicates they were going out of spec and being shut down by the engine control system.

[Superpluto126]

Def a Methane Leak, although I do wonder what caused it. Was it Quality Control, an Issue with the plumbing or perhaps something more sinister....(Enter the Dark SpaceX Theory /j)

[darthgently]

1 hour ago, Nuke said:

i kind of doubt an engine failure, because the cascade failure would have been faster and a lot more dynamic. engines blinking out one by one indicates they were going out of spec and being shut down by the engine control system.

I seriously doubt an engine failure for the same reasons

[darthgently]

47 minutes ago, Superpluto126 said:

Def a Methane Leak, although I do wonder what caused it. Was it Quality Control, an Issue with the plumbing or perhaps something more sinister....(Enter the Dark SpaceX Theory /j)

If it were malicious then I’m thinking inside job given the apparent location of the leak.  That said I think the odds it was malicious is about 1 in 10,000, because of the internal location and unlikelihood that it would be an inside job

The kind of vandalism and sabotage I’d expect, if it happened, would be something like large caliber sniper fire during launch.  I don’t think it’s a coincidence that the on land keep out zone during launch is not just a good explosion safety buffer but also deep enough that a precise sniper shot to some specific small area on the rocket would be extremely difficult.  Also I’m picturing Predator or other drones with thermal and other looking for anyone in that zone as launch approaches.  I’d imagine the same at Canaveral, Vandy, and Wallops.  But I have no idea.  It just seems extremely likely given military aviators, drone operators surely included, are always wanting more flight hours and real performance on record for when review time comes up and every branch loves to exercise the tech.  So I assume these launches, especially anything NRO or military related, get some extremely good security support.  I hope I’m not wrong

Edited January 20 by darthgently

[tater]

 

Stream hosed. Liftoff

https://x.com/i/broadcasts/1OyKAZZBwRqGb

 

back

fairing sep

No video now, had been booster vid

[tater]

Entry burn happened

Another routine flight to space (and back), even if stream was sorta fubar.

[tater]

Possibly Starshield were hitching a ride with Starlinks, hence the wonky stream coverage.

[magnemoe]

11 hours ago, Superpluto126 said:

Def a Methane Leak, although I do wonder what caused it. Was it Quality Control, an Issue with the plumbing or perhaps something more sinister....(Enter the Dark SpaceX Theory /j)

I assume that the firewall lies below the trust structure who is below the lower bulkhead. It might also be trust structure inside the tank but its not relevant here. 

The roof in the engine bay here. Its piping going from the down comer to the engine, I assume the first flange here is inside the void between the firewall and bulkhead. 
If you get an leak here, and this space is probably multiple compartment divided by the trust structure so an leak could easy fill this area and if it got the methane to drain faster it was an significant leak. 
Bursting this might also break the LOX line 

[Exoscientist]

  Flames can be seen coming out at the location of the aft flap hinge. The relative location of the hinge can be seen here:

 It appears to be below the rear tank dome and somewhat above the engines. This though doesn’t mean the leak and fire didn’t originate at the engines, but it could be that the flames become visible there outside because the hinge was the easiest point for the flames to escape.

 SpaceX should release any imaging inside the engine bay while the engines are firing.

  Bob Clark

[tater]

 

[AckSed]

 Scott Manley telling us how rocket companies file NOTAMs and TFRs which always kick in... and DRAs (Debris Response Areas) that may kick in. The relevant shot for this thread is at 8:30, showing 4 pre-approved DRAs for Flight 7:

Problem is, these aren't shared as publicly as the more common NOTAM.

Edited January 21 by AckSed
Additional detail

[RCgothic]

On 1/16/2025 at 11:03 PM, tater said:

I watch the real stream, all other patter is garbage.

The hinge fire is news to nobody in this thread who actually reads it instead of doing nothing but post pet theories.

Also nice use of a diagram of SN8. The 3rd hinge on SN33 is comfortably above the false ceiling, exactly where we'd expect to see a plumbing leak.

Edited January 21 by RCgothic

[darthgently]

31 minutes ago, AckSed said:

 Scott Manley telling us how rocket companies file NOTAMs and TFRs which always kick in... and DRAs (Debris Response Areas) that may kick in. The relevant shot for this thread is at 8:30, showing 4 pre-approved DRAs for Flight 7:

Problem is, these aren't shared as publicly as the more common NOTAM.

These static and conditional hazards zones are what I was trying to get at over the last many posts on the topic but the acronyms slip my mind and I knew I could rely on Scott Manley to sort it out.  That is my story and I’m sticking to it

17 minutes ago, RCgothic said:

The hinge fire is news to nobody in this thread who actually reads it instead of doing nothing but post pet theories.

The middle hinge is well above the engines, close to the root of the tank dome.

Yep. It is adjacent to the area above the engine firewall and below the tank.  Which is exactly in line with Musk’s fairly quick statement about a leak in this area.   I, and others I think, pointed this out but it was lost in the kerfuffle

[RCgothic]

Yeah, there was plenty of discussion of it up-thread, the post I quoted was @tater getting the first mention in.

[tater]

 

[JoeSchmuckatelli]

I was looking at the Anatomy Pic above - wondering if there's any sketches of the plan for the cargo bay / faring without nose tank or what they plan for the giant pipe that runs down the center line? 

Could that be routed from the core of the ship to the perimeter... Or would customers need to build a load around that? 

[GuessingEveryDay]

15 minutes ago, JoeSchmuckatelli said:

I was looking at the Anatomy Pic above - wondering if there's any sketches of the plan for the cargo bay / faring without nose tank or what they plan for the giant pipe that runs down the center line? 

Could that be routed from the core of the ship to the perimeter... Or would customers need to build a load around that? 

I remember a rendering where the pipe to the nose tank is attached to the inside of the nose, following the curve. It would look like that if it was from one angle.

Found it.

[Superpluto126]

I think for Payloads that can't use the Pez dispenser SpaceX will Pursue one of 2 options

1. A Larger Version of the Pez dispenser, it will be capable of launching Medium sized SATs in decent sized numbers. I don't see why this wouldn't be possible but it might require an extensive re-design of the Rings used to construct the ships.

2. Fully Expendable ship with ride share like payload as it will have a  LOT of payload capability. Probably stretched as well like V3, if a Payload is so big it takes up the entire Bay then that's gonna be a option as well.