Starship flight 5 preparations - DISCUSSION

[chopsticks]

Key phrase here: angle of attack. It seems like it should be fairly easy to measure (roughly) using some of the RTLS ground track footage.

[meekGee]

Wait are you saying the body axial direction is an indicator of the trajectory IIP?  Or even of the momentary direction of flight?

I guarantee you that it is neither.  It is entirely unrelated.

Axial direction (pitch) and momentary direction of flight (flight path angle) both directly affect the IIP, so they are inextricably related. I am simply showing that the axis of the rocket is pointed uprange of the landing pad, and is never pointed offshore prior to the landing burn, which is the point of the discussion.

Irrespective, I can't think of any reason why you'd want to overshoot towards civilization and only divert back to the pad if all goes well.

Prior to the landing burn, the Falcon 9 (and Heavy) IIP has to be uprange of the landing point. This is because a retrograde landing burn walks the IIP back downrange. With a nominal landing, no diversion is required.

Noone but you has said anything about overshooting towards civilisation, that's just hyperbole.

They affect it, but don't indicate it.

If the rocket is pointing inland (pre burn) it merely means it's using body lift. The IIP can be anywhere. Post burn it kinda means it's killing horizontal velocity  but again, the IIP can be anywhere.

[dabomb6608]

No, I'm simply showing that your previous assertion that

They aim at the shoreline or slightly offshore.

is incorrect.

Except it is correct. The only thing your attached image shows is that to divert towards the landing zone the booster ends up "pointing" inland past it. That doesn't mean that is where they are aiming.

If the booster was to instantly begin a free-fall with zero control inputs at the exact moment that snip was taken it would land somewhere between the pad and offshore. It wouldn't land anywhere between the pad and the landing strip.

There is zero reason for them to have either booster, at any point, inland of the landing location during landing approach. They have every reason to keep it in a predetermined corridor that extends from the landing location to some point offshore. That way if it exits that corridor they can terminate the booster in a safe manner away from civilization.

[Vultur]

That would not shorten the time until Starship is operational.  Booster re-usability is on the critical  path for that, and each booster catch test is also a Ship test. They will thus test Ship re-light each time they test booster catch. My GUESS: we will see a successful re-light on IFT-5.

Not to mention that ability to catch is critical for both SH and SS in the presently concieved form. They must have confidence that will work ASAP, which requires obtaining the data needed to make any corrections to SH-SS-OLM-whatever ASAP, which means attempting a catch ASAP. Doing it with a booster is the fastest path to that goal. If they can't reach that goal, it implies major changes to both SH and SS (e.g., legs or somesuch); they need to buy down that risk sooner rather than later.

Good point.

I still think it's odd they didn't go with the proven F9 booster recovery mechanism with legs to get a minimum viable Starlink launcher, with expendable second stage, [and do Tower catch and second stage recovery later], given the comment about launching Starlink on Starship quickly being critical to the company survival....

But maybe v2 mini on Falcon 9 worked better than expected?

[TheRadicalModerate]

I still think it's odd they didn't go with the proven F9 booster recovery mechanism with legs to get a minimum viable Starlink launcher, with expendable second stage, [and do Tower catch and second stage recovery later], given the comment about launching Starlink on Starship quickly being critical to the company survival....

But maybe v2 mini on Falcon 9 worked better than expected?

Remember that there are likely to be huge performance reductions launching Starlinks from Boca Chica, due to the need to dogleg to get to high-ish inclinations without overflying populated areas.  It's possible that the economics of launching v2 minis on F9 are better than launching maxis on Starship--unless they get optimizations like tower catch working.

I really don't expect large-scale Starlink launches to occur before they've got things up and running at the Cape.

[OTV Booster]

Ship testing is probably being a bit delayed by the need for an FAA approval of the booster catch attempt, but probably not by much. Then will not get a license to send Ship to orbit until after they demonstrate engine restart in 0 g, so they may as well test re-entry on the Ship flights until that happens.

This part is my concern. Given that IFT 4 wasn't ruled a mishap, if IFT 5 was going to repeat the same profile they could probably have already had the license, launched it, and demonstrated engine restart.

Booster re-usability is more urgent, because each expended booster is quite expensive. I suspect they would like to start catching consistently before they start expending Raptor 3 engines.  Losing a few more multiples of 33 already-produced old Raptors does not matter, but they need to refine the catch before Raptor 3.

Judging from past record, Raptor 3 will undergo some rapid iteration, just like everything else SX builds. It's doubtful the first 2-3 ships worth would be reused although admittedly it would be good inspect them sans saltwater.


Only SX is in a position to call the shot. Booster catch first or flight 4 redux? Most of the pros and cons have been discussed but only SX knows what SX knows. My gut still leans towards one more water landing but IANARS or an SX insider. Whatever they choose, I hope it works out well.

[Vultur]

Ship testing is probably being a bit delayed by the need for an FAA approval of the booster catch attempt, but probably not by much. Then will not get a license to send Ship to orbit until after they demonstrate engine restart in 0 g, so they may as well test re-entry on the Ship flights until that happens.

This part is my concern. Given that IFT 4 wasn't ruled a mishap, if IFT 5 was going to repeat the same profile they could probably have already had the license, launched it, and demonstrated engine restart.

Booster re-usability is more urgent, because each expended booster is quite expensive. I suspect they would like to start catching consistently before they start expending Raptor 3 engines.  Losing a few more multiples of 33 already-produced old Raptors does not matter, but they need to refine the catch before Raptor 3.

Judging from past record, Raptor 3 will undergo some rapid iteration, just like everything else SX builds. It's doubtful the first 2-3 ships worth would be reused although admittedly it would be good inspect them sans saltwater.


Only SX is in a position to call the shot. Booster catch first or flight 4 redux? Most of the pros and cons have been discussed but only SX knows what SX knows. My gut still leans towards one more water landing but IANARS or an SX insider. Whatever they choose, I hope it works out well.

Don't we already know what they chose (booster catch with chopsticks), otherwise they wouldn't be waiting on approval from the FAA?

[OTV Booster]

Ship testing is probably being a bit delayed by the need for an FAA approval of the booster catch attempt, but probably not by much. Then will not get a license to send Ship to orbit until after they demonstrate engine restart in 0 g, so they may as well test re-entry on the Ship flights until that happens.

This part is my concern. Given that IFT 4 wasn't ruled a mishap, if IFT 5 was going to repeat the same profile they could probably have already had the license, launched it, and demonstrated engine restart.

Booster re-usability is more urgent, because each expended booster is quite expensive. I suspect they would like to start catching consistently before they start expending Raptor 3 engines.  Losing a few more multiples of 33 already-produced old Raptors does not matter, but they need to refine the catch before Raptor 3.

Judging from past record, Raptor 3 will undergo some rapid iteration, just like everything else SX builds. It's doubtful the first 2-3 ships worth would be reused although admittedly it would be good inspect them sans saltwater.


Only SX is in a position to call the shot. Booster catch first or flight 4 redux? Most of the pros and cons have been discussed but only SX knows what SX knows. My gut still leans towards one more water landing but IANARS or an SX insider. Whatever they choose, I hope it works out well.

Don't we already know what they chose (booster catch with chopsticks), otherwise they wouldn't be waiting on approval from the FAA?

That's where things stand right now.


What if (doncha hate that word?) it starts looking like it'll take the FAA another 60-90 days? It would then make sense to relabel the flight 5 application for flight 6 and resubmit a new flight 5 application as a near repeat of flight 4. The ok should be quick.

[FutureSpaceTourist]

https://twitter.com/infographictony/status/1833116508278624267

Version 1.0: “Here’s the catch” - Starship flight test 5 (unofficial) infographic poster. Consider this a work-in-progress. Myself & @LunarCaveman are still in the progress of writing the text plus some mission clarifications are needed. As we get closer to the launch, certain details may need to be updated. #SpaceX

[woods170]

Per the most recent SpaceX Update on their website: SpaceX has received notification from the FAA that the IFT-5 launch license is not expected to be issued before late November 2024, due to "superfluous environmental analysis".

I can imagine the Artemis HLS people at NASA are not going to be too happy about this. This is literally one government agency (the FAA) becoming an obstacle for another government agency (NASA).

[TheKutKu]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

[DanClemmensen]

Per the most recent SpaceX Update on their website: SpaceX has received notification from the FAA that the IFT-5 launch license is not expected to be issued before late November 2024, due to "superfluous environmental analysis".

I can imagine the Artemis HLS people at NASA are not going to be too happy about this. This is literally one government agency (the FAA) becoming an obstacle for another government agency (NASA).

I have lost track. Who is responsible for the environmental analysis, and what laws or regulations cause the delay in this analysis? In earlier cases the governing law was NEPA, and FAA was forced to wait for other agencies including FWS to complete the analyses and public comment periods. If this is the case this time, then adding resources to FAA will not reduce the bureaucratic delay. This would require adding resources to other agencies or changing the underlying law.

[matthewkantar]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

Don’t confuse cause and effect. If SpaceX knows the the feds are going to hobble launch cadence, they will take that time to work on GSE.

[dabomb6608]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

All of the work being completed to Tower & GSE would have been in efforts to meet the anticipated license date of mid-september. If they had known things were going to be delayed till November I seriously doubt they would have gone for a catch on the next flight. But now they are "in too deep" and it likely doesn't make sense to backtrack to do another IFT-4 at this stage.

[Vultur]

The possibility of even more delays might make it worth switching even at this point, if they could get an IFT4 flight profile approved quickly.

[TheKutKu]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

Don’t confuse cause and effect. If SpaceX knows the the feds are going to hobble launch cadence, they will take that time to work on GSE.

They quite literally said that they expected a mid-september license until recently.

"We recently received a launch license date estimate of late November from the FAA, the government agency responsible for licensing Starship flight tests. This is a more than two-month delay to the previously communicated date of mid-September"

[butters]

All of the work being completed to Tower & GSE would have been in efforts to meet the anticipated license date of mid-september. If they had known things were going to be delayed till November I seriously doubt they would have gone for a catch on the next flight. But now they are "in too deep" and it likely doesn't make sense to backtrack to do another IFT-4 at this stage.

Any mission profile would require the pad deluge system. They wouldn't have been able to quickly repeat the IFT-4 profile, because the regulators effectively came to conclusion that the license for IFT-4 was granted in error due to the incorrect type of application that was filed for the water discharge.

[novo2044]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

Don’t confuse cause and effect. If SpaceX knows the the feds are going to hobble launch cadence, they will take that time to work on GSE.

They quite literally said that they expected a mid-september license until recently.

"We recently received a launch license date estimate of late November from the FAA, the government agency responsible for licensing Starship flight tests. This is a more than two-month delay to the previously communicated date of mid-September"

Onerous bureaucracy is one thing, unpredictable bureaucracy is quite another.  Everyone seems surprised by this shift even people who are usually in the know.  Honestly things like this shouldn’t happen.  Wonder if there’s more backstory here   

[Vultur]

All of the work being completed to Tower & GSE would have been in efforts to meet the anticipated license date of mid-september. If they had known things were going to be delayed till November I seriously doubt they would have gone for a catch on the next flight. But now they are "in too deep" and it likely doesn't make sense to backtrack to do another IFT-4 at this stage.

Any mission profile would require the pad deluge system. They wouldn't have been able to quickly repeat the IFT-4 profile, because the regulators effectively came to conclusion that the license for IFT-4 was granted in error due to the incorrect type of application that was filed for the water discharge.

I don't think this delay is about the deluge system at all, but about marine life + sonic boom impacts of the changed flight profile.

[woods170]

They carefuly say that the "The Starship and Super Heavy vehicles for Flight 5 have been ready to launch since the first week of August." without mentioning the Launch tower and GSE...

My understanding is that the launch was NET Early october before this, this would mean 1-1.5 months of delay...

Also it seems like the FAA disagrees that the additional time is due to environmental review: https://x.com/LauraForczyk/status/1833529377361170645

Don’t confuse cause and effect. If SpaceX knows the the feds are going to hobble launch cadence, they will take that time to work on GSE.

They quite literally said that they expected a mid-september license until recently.

"We recently received a launch license date estimate of late November from the FAA, the government agency responsible for licensing Starship flight tests. This is a more than two-month delay to the previously communicated date of mid-September"

Current modifications to the OLM and GSE are expected to be completed to support the previously communicated license date of mid-september. Remember: SpaceX is a major proponent of the JIT principle. When FAA confirms the expected license date shifts to late November, it is a given that SpaceX will use the additional time to start implementing upgrades and modications that were originally planned for AFTER a early October IFT-5 launch.