SpaceX Starship IFT-4 : When will it launch?

[jongoff]

Another poll, this time for when IFT-4 will fly. I provided answers to hopefully cover all the bases (though I'll be surprised if the last one gets a lot of takers). Basically, when will IFT-4 liftoff, once you factor in guesses and how long it will take SpaceX to analyze IFT-3 flight data, figure out what went wrong, make whatever tweaks they think they need to the hardware/software, finish their mishap report, repair any pad damage, get FAA permission to fly again, etc.

I know we don't have a lot of data yet, but that's when polls are the most fun...

I'll leave this open for 5 days to force people to make guesses on incomplete information. Though I did click the "allow users to change their vote" box, in case people want to change their minds during that 4 day window.

If you want to share your rationale, I'm interested in hearing why people guess what they do.

Also, let me know if you think I have too much or too little granularity. For instance, if you'd like me to split out Q3 into July, Aug, Sep, let me know.

~Jon

[jongoff]

My guess is sometime in June. Because they didn't complete their in-space relight, I think the FAA is likely going to force them to do another IFT demo (it's possible SpaceX could argue otherwise and convince them, but I think that's low probability), and they have to do a mishap report. I think this mishap report is likely going to be easier than the last one, since the flight was more successful, but it seems like it's still in the territory where it'll take some time to work through. There's a chance they could get everything done in time for an end of May flight, but I think it's more likely to slip into June. Given that this flight was more successful than the last one, I don't think it's as likely to slip into July. Possible, but I think June is the safest bet.

~Jon

[Eer]

I'm guessing May - which gives them about 10 weeks to sort things out.

I suspect the little extra delay for the Flight 3 license involved getting the Indian Ocean landing zone reviewed and cleared.  Not an issue for Flight 4 - they've been there, done that.

The booster control authority problem is one I expect they have expertise to deal with promptly.

The starship control authority during coast and fuel transfer operations worries me a bit more ... I hope their modeling of the ulage thruster solutions have been good and had margins necessary to address the issues they experience.

I'm also somewhat concerned about the payload bay door - not convinced that open/close test went the way they wanted it to, and we know they've been adjusting how the door is strengthened and so forth.  But I'm guessing they can throw more steel at it if that's what it takes without adding too much time.

So, 2 weeks in March, 8 more weeks in April and May (give or take one), I think will be enough.

[sdsds]

May 17, 2024. Or with 50% confidence, sometime between May 4, 2024 and Jun 8, 2024. Either way I went with 'May.'

And yes, I totally fabricated some underlying assumptions.

[Herb Schaltegger]

I’m guessing May for a couple/few reasons. First, for two consecutive launches now, Super Heavy has managed to complete startup of all 31 engines and full-duration ascent burns. This, combined with a basically flawless prelaunch flow and rapid propellant loading cycle indicates a maturing operational system on the part of SpaceX and resultant reduced risk from Pad Clear through staging.

Second, we’ve now seen two flawless hot staging procedures and in-flight starts of Ship’s 6 Raptors. Again, this indicates a maturing technological level and confidence in existing systems and procedures, and thus reduced risk.

Third, we’ve now seen a second consecutive Ship burn to (near) orbital trajectory. Yes, I know Flight 2 was terminated due to operational issues related to LOX dumping but the engines themselves operated flawlessly. Again, this demonstrates fundamental technological maturity, with complications induced from basic lack of operational experience (e.g., LOX dumping too early) rather than fundamental problems.

The biggest, most important thing that “broke” in this flight - attitude control during coast - is not something that affected the overall risk assessment which underlies the FAA’s regulatory basis for approval or disapproval of a launch license application to a suborbital trajectory.

The other big thing that broke, from the FAA’s perspective, is attitude control for the returning Super Heavy booster. Worth noting that - again - the FAA’s primary raisin d’etre is mitigating risk to the public. Super Heavy crashing into the sea inside the keep-out zone established before launch achieves that goal whether or not “soft landing” in the ocean occurs or not.

Therefore, once SpaceX completes its own internal investigation and figures out how they intend to mitigate those shortfalls, the FAA will quickly approve the conclusions and amend the launch license to allow Flight 4. Given how fast SpaceX iterates, Six weeks for data analysis and hardware/software modifications plus another couple weeks for FAA to review and approve results in a launch campaign sometime in mid-late May.

[jongoff]

I’m guessing May for a couple/few reasons. First, for two consecutive launches now, Super Heavy has managed to complete startup of all 31 engines and full-duration ascent burns. This, combined with a basically flawless prelaunch flow and rapid propellant loading cycle indicates a maturing operational system on the part of SpaceX and resultant reduced risk from Pad Clear through staging.

Second, we’ve now seen two flawless hot staging procedures and in-flight starts of Ship’s 6 Raptors. Again, this indicates a maturing technological level and confidence in existing systems and procedures, and thus reduced risk.

Third, we’ve now seen a second consecutive Ship burn to (near) orbital trajectory. Yes, I know Flight 2 was terminated due to operational issues related to LOX dumping but the engines themselves operated flawlessly. Again, this demonstrates fundamental technological maturity, with complications induced from basic lack of operational experience (e.g., LOX dumping too early) rather than fundamental problems.

The biggest, most important thing that “broke” in this flight - attitude control during coast - is not something that affected the overall risk assessment which underlies the FAA’s regulatory basis for approval or disapproval of a launch license application to a suborbital trajectory.

The other big thing that broke, from the FAA’s perspective, is attitude control for the returning Super Heavy booster. Worth noting that - again - the FAA’s primary raisin d’etre is mitigating risk to the public. Super Heavy crashing into the sea inside the keep-out zone established before launch achieves that goal whether or not “soft landing” in the ocean occurs or not.

Therefore, once SpaceX completes its own internal investigation and figures out how they intend to mitigate those shortfalls, the FAA will quickly approve the conclusions and amend the launch license to allow Flight 4. Given how fast SpaceX iterates, Six weeks for data analysis and hardware/software modifications plus another couple weeks for FAA to review and approve results in a launch campaign sometime in mid-late May.

Good arguments. I definitely think May is defendable, I just think it's really easy for mid-late May to slip into June if anything takes longer than anticipated. Maybe doing rockets in Mojave at the start of my career has made me somewhat paranoid, but I think the "Murphy was an optimist" take usually serves me well. And if I'm wrong, I'll most likely be pleasantly surprised. :-)

~Jon

[catdlr]

I selected June:  the re-test of the fuel transfers (if that failed), work on the payload door (if failed) and perhaps re-installation of RCS instead of what failed in this flight, these may all require the ship to have some time off to undergo extensive modifications before its flight,  and that's not including any booster mods to ensure relighting at landing.

Best
Tony

[panjabi]

I voted never for Starship/Superheavy.  Has to be redesigned/will be redesigned.   

There are too many conflicting design goals for Starship.  Just too much stuff going on with mishap investigations and dozens of corrective actions required for each new flight. 

Every design modification of Starship for different mission use cases will drag out the time needed for FAA approvals.  Reliability metrics are just not materializing for any sensible business case. 

Anticipating that a successful New Glenn flight will make this more obvious.  It's over.

OK, Jeff Bezos ... 

[19 Orionis]

Level 1 controllability on the Cooper-Harper scale isn’t being demonstrated.
>>> Never.

I hope that you will accept Jeff Bezos as your methane messiah so that you may eventually be with him on Mars for eternity.

[TheRadicalModerate]

My guess is sometime in June. Because they didn't complete their in-space relight, I think the FAA is likely going to force them to do another IFT demo...

I agree.¹  Now that they've demonstrated a potential relight problem, it's an awfully big hunk of space junk to leave to an uncontrolled entry.

I doubt they'll bother to retrofit S29 with sensible RCS thrusters, but I'm convinced that they'll have to go to a combusting thruster in the not-too-distant future.  If they did this sooner rather than later, they might be able to convince the FAA that the thrusters could handle a controlled deorbit if the Raptors went screwy.  However, unless they've concluded that the vehicle is uncontrollable with ullage gas during suborbital tests, they'll stick with the existing cowbells/vents, then make the modifications in the S32 or S33 timeframe.

If it really is uncontrollable for suborbital, then June is probably out.  I know there have been rumors of tests of thrusters at McGregor, but it doesn't seem likely that they're ready to slap a few of them on flight hardware yet.

_________
¹I assume you're using "IFT" as a synonym for "suborbital" and "not yet capable of deploying Starlinks".

[rfdesigner]

I'm working on the principle of continuous improvement..   to get more than 5 launches in this year (I seem to remember them discussing more launches) that means they want at least 6.. to get that many in where they get a bit quicker between each launch my maths says about mid june for IFT4.. with things accelerating as time moves on, they could get to IFT8 or 6 flights for 2024 by improving by about 23% per launch..  and we're seeing various stages of preparation improving, not least of which is the readyness of the next stack at launch of the last one.  Just guesswork really.  I'm assuming that they'll stick with the "IFTn" flight numbering until they enter service, so I expect to see the first round the moon and back or even the first mars test flight being an IFT.

[Metalskin]

I'm assuming from comments on other threads that getting approval for flights is going to continue as is until they can prove deorbit capability. So I see relight as a major focus for SpaceX. I suspect it's more likely that there will be a bit of work to get it sorted based on their data from this flight, so I picked June.

I hope I'm wrong and it's way sooner. I was a tad pessimistic for this flight (had picked April), so maybe I'm wrong for the next one as well, which I would be happy about :-)

[Kazioo]

If they go for another "just data gathering" trebuchet throw with mostly software changes -> May.

If they decide to redesign RCS for next flight to increase the chances of full reentry -> Q3.

[Vettedrmr]

I voted never for Starship/Superheavy.  Has to be redesigned/will be redesigned.   

There are too many conflicting design goals for Starship.  Just too much stuff going on with mishap investigations and dozens of corrective actions required for each new flight. 

Every design modification of Starship for different mission use cases will drag out the time needed for FAA approvals.  Reliability metrics are just not materializing for any sensible business case. 

Anticipating that a successful New Glenn flight will make this more obvious.  It's over.

Excellent use of the font.

[Steve G]

I don't care how rich Elon Musk is, but he can't continue to afford a Starship-Super Heavy, and 39 Raptor engines, every three or four months for incremental improvements. Every launch seems to uncover a new weakness(s). He needs a home run on the next launch and that's only after a thorough, meticulous review, more ground testing, and implement changes for a fully successful Flight 4. Flying again in three or so months will just be another incremental improvement with yet another review and more weaknesses revealed. The last thing he (and the Lunar Starship Program) can afford is an Apollo 6 type of setback, or worse, a catastrophic failure. They need to pause and do it right the next time around, and that's not going to happen with an early summer launch.

[Vettedrmr]

I don't care how rich Elon Musk is, but he can't continue to afford a Starship-Super Heavy, and 39 Raptor engines, every three or four months for incremental improvements. Every launch seems to uncover a new weakness(s). He needs a home run on the next launch and that's only after a thorough, meticulous review, more ground testing, and implement changes for a fully successful Flight 4. Flying again in three or so months will just be another incremental improvement with yet another review and more weaknesses revealed. The last thing he (and the Lunar Starship Program) can afford is an Apollo 6 type of setback, or worse, a catastrophic failure. They need to pause and do it right the next time around, and that's not going to happen with an early summer launch.

Then you're going to have a crisis, because that's EXACTLY how SpaceX operates, and with their track record of F9, I doubt if they're going to go back to the old space way of doing things.

[frog]

I don't care how rich Elon Musk is, but he can't continue to afford a Starship-Super Heavy, and 39 Raptor engines, every three or four months for incremental improvements. Every launch seems to uncover a new weakness(s). He needs a home run on the next launch and that's only after a thorough, meticulous review, more ground testing, and implement changes for a fully successful Flight 4. Flying again in three or so months will just be another incremental improvement with yet another review and more weaknesses revealed. The last thing he (and the Lunar Starship Program) can afford is an Apollo 6 type of setback, or worse, a catastrophic failure. They need to pause and do it right the next time around, and that's not going to happen with an early summer launch.

Of course he can, if they demonstrate on orbit restart of Raptors, and  resolve the station keeping issues, than ft-6 and beyond can carry Starlink sats paying for the flights

[ZachS09]

My out of the blue guess is within the first week of June.

[StuffOfInterest]

I threw my marker on June.

If everything had gone well I would have said about two months for the next flight, but with what we saw it is going to take at least another month.  Both vehicles are going to need some type of modification.  Superheavy had issues relighting engines, which may not be trivial to fix.  There was also some oscillation during descent that may be related to the grid fins either not adjusting at the right speed or not having enough effect.  As for Starship, payload bay door had issues and something will have to be done about the tumble.  There was the debris shower as well, but that may have been due to clogged plumbing as other have speculated.

Developing and implementing theses fixes on already built hardware will take a little bit of time.  Not years, maybe not even multiple months, but definitely a few weeks plus a few weeks more for testing to validate the changes.

[Vettedrmr]

Of course he can, if they demonstrate on orbit restart of Raptors, and  resolve the station keeping issues, than ft-6 and beyond can carry Starlink sats paying for the flights

I know this if the Flight 4 thread, but I anticipate Flight 5 will carry the first Starlink payload.  Whether that'll be V2 or V2mini satellites IDK.