NASA Artemis 1 going to the Moon (launched Nov 16)

[Vanadium 50]

Godspeed Snoopy!

Wasn't that Apollo 10?

 

[bob012345]

Wasn't that Apollo 10?

Borrowed from Friendship 7. "Godspeed, John Glenn"

 

[hutchphd]

Snoopy was Lunar Module for Apollo 10. Godspeed was Scott Carpenter's heartfelt benediction at t=0 in Glenn's countdown

 

[bob012345]

Snoopy was Lunar Module for Apollo 10. Godspeed was Scott Carpenter's heartfelt benediction at t=0 in Glenn's countdown

There is a "passenger" on this new rocket named Snoopy hence the reference.

 

[mfb]

They have a launch window on Monday and Tuesday. After that, they would need to wait for at least 2 weeks.

They had one Monday, but they can't fix the problem in these two days and with the rocket on the pad.

NASA to Stand Down on Artemis I Launch Attempts in Early September, Reviewing Options

There is a range of launch windows September 19 – October 4. That can only be met if the rocket doesn't have to go back to the VAB. That means extending the certification of the flight termination system and fixing all issues with the rocket on the launch pad.
The following range is October 17 – October 31.

 

[neilparker62]

He seems to me like a mad megalomaniac, who believes we're living in a computer simulation from the future. It's frightening how much wealth and power are in the hands of one man, especially one with crackpot notions.

Others, no doubt, will see him as mankind's saviour.

On the whole I think I prefer Elon firing his rockets towards Mars than others firing hither and thither here on Earth. Space is where effort and energies should sensibly be spent. So roll on Elon!

 

[Buzz Bloom]

I would much appreciate it if someone would make clear what the following abbreviations mean: MN and N1.
The reference is from post #56 by @mfb.
39 MN for SLS (Block 2 will have 41 MN)
35 MN for Saturn V
31 MN for the Space Shuttle
45 MN for N1.

 

[Ibix]

I would much appreciate it if someone would make clear what the following abbreviations mean: MN and N1.
The reference is from post #56 by @mfb.
39 MN for SLS (Block 2 will have 41 MN)
35 MN for Saturn V
31 MN for the Space Shuttle
45 MN for N1.

N1 was a Soviet rocket that was supposed to be comparable to the Saturn V, but kept exploding. MN is mega Newtons of thrust, I imagine.

 

[.Scott]

It's an interesting cultural difference between SpaceX and NASA in that what would be a failure for NASA is a 'test to failure mode to learn" experiment to SpaceX.

It's mostly a difference in tempo. When SpaceX RUDs, they already have the next one in the works. If NASA/Boeing RUDs with the SLS launch, it would literally take an [unlikely] act of Congress to recover.

At this point, a real SLS setback would be not launching before Starship. Elon has said that the Starship launch will happen this year - though he acknowledges that SpaceX has a reputation for turning the "impossible" into "late". He has already booked the first paying Starship launch for 2024.

I'm fully expecting Artemis 1 to launch on SLS first. But it's far from a certainty.

I am also fully expecting that there will two successful Starship launches by the end of 2023. And that's when the Starship vs. SLS comparison will become very hard to ignore. NASA wants both to succeed, but at some point it could start looking like the crew missions to ISS - where SpaceX chalks up several missions before the competition makes their first.

 

[.Scott]

It looks like: Set up shop at the pad; With the cryo plumbing available at the pad, explore and perhaps fix the problem; bring SLS back to the VAB for recertification; redeploy to pad; wait for a launch window and avoid conflicts with ISS launch activity.

 

[mfb]

NASA wants to fix the hydrogen issue with the rocket on the pad. That could allow a launch in the second half of September, and it will mean more time for tests with the rocket and the launch tower. Downside: The certification for the flight termination system runs out and they can't access it, so this plan only works if they get an extension. This is not a new constraint - I would expect that NASA applied for it long ago. Would be a strange coincidence if the normal process was almost done just at the time they need it, so I'm not sure what's going on.
If they don't get that extension the vehicle needs to roll back.

 

[.Scott]

NASA wants to fix the hydrogen issue with the rocket on the pad. That could allow a launch in the second half of September, and it will mean more time for tests with the rocket and the launch tower. Downside: The certification for the flight termination system runs out and they can't access it, so this plan only works if they get an extension. This is not a new constraint - I would expect that NASA applied for it long ago. Would be a strange coincidence if the normal process was almost done just at the time they need it, so I'm not sure what's going on.
If they don't get that extension the vehicle needs to roll back.

From what I have read, the purpose in doing the work at the pad is to actually work the problem with the plumbing attached.

The last I read about the schedule was like this one from livesciences:

After the launch was called off, NASA Administrator Bill Nelson said the rocket's next launch window will open in early October, but because other missions will be prioritized over Artemis 1, the third launch attempt likely will fall in the middle of the month.

The recertification relates to the flight termination system. It expires because there are batteries that need to be replaced. Those batteries can only be replaced with SLS in the VAB. At this point, it seems as though a visit to the VAB is unavoidable.

However! :
We should be getting additional details 75 minutes from now.
Nasa has scheduled a livestream report on this at 11am ET.

 

[.Scott]

Per the 11am call:

They need to comply with test range requirements.
They are asking for a waiver to extend their FTS batteries retest requirements (to avoid the VAB visit).
(batteries are mostly on the core stage - one for each "command receiver/decoder")
Need to deconflict with DART mission's use of Deep Space Network.
Need to avoid Crew-5 with regards to replenishing issues at the range.

They need to remove and replace 4" and 8" seals on the quick disconnect lines. (at pad)
They reconnect and retest - all at pad.
Cryo event expected at 9/17 at pad.
Tanking process will now involve more smooth-flow fueling.

They have asked for the launch test range for Sept 23 and 27.

Also: There was an inadvertent Saturday pressure rise of the H2 lines over the interface spec. This was the result of late changes to the fuel loading procedure. Unknown if that was a cause of the leak.

 

[mfb]

Launch dates in late September / early October

Crew-5 is planned for October 3. Moving that back a few days would be possible - the weather might do that anyway - but moving it more would need more changes to the ISS schedule.

There is another certification limit: It can only go back to the VAB two more times. Of course, as with all other certifications, this might get extended if necessary.

 

[.Scott]

The FTS battery limit could be a problem. The original limit was 20 days based on the device spec. It was already waived to 25 days based on actual observed battery performance. Bumping it to 40+ days could be a non-starter. A visit to the VAB may be unavoidable.

 

[mfb]

NASA wouldn't keep the rocket on the pad if they were not pretty confident to get that extension.

Repair work is ongoing and they want to a test tanking next Saturday.

 

[.Scott]

NASA wouldn't keep the rocket on the pad if they were not pretty confident to get that extension.

Repair work is ongoing and they want to a test tanking next Saturday.

Up until Sept. 17, it's been on the pad because the leak is at the Rapid Disconnect seals. They have needed at the pad to see the problem and repair it. It needs to remain there until the repair is tested (now scheduled for the 17th).

If they get the FTS battery extension, it raises this question: When the 20-day to 25-day extension was granted, why didn't the analysis support an extension to 40+ days? Or, if it did, why was it not immediately extended to 40+ days?

 

[.Scott]

According to "Florida Today", the cryo test will be No Earlier Than (NET) 9/21 and the launch will be NET 9/27.

In that same article:

But avoiding a rollback is dependent on the Space Force: the military branch is responsible for public safety and requires the rocket's flight termination system, or FTS, be recertified every 25 days. The current certification for the FTS, which is designed to destroy the rocket in the event of an emergency, expired Sept. 6.

Officials said they submitted FTS extension requests with the range and are waiting for a response.

9/27 would put the battery period at 46 days. Space Force needs to start with the assumption that there is no FTS until demonstrated otherwise. So they could clear the launch without a VAB visit if it can be safely done with no FTS (not a prayer) or if there is solid reason to believe that the FTS would work (sound like a stretch to me).
The only reasons I see for hope is that 1) An extension was submitted - so they must have come up with some argument; and 2) Space Force hasn't already ended this conversation.

 

[mfb]

So they could clear the launch without a VAB visit if it can be safely done with no FTS (not a prayer)

I don't see that happening. The rocket is big and you can't shut down the SRBs. If the system breaks apart and can't be destroyed they could end up anywhere.

or if there is solid reason to believe that the FTS would work

NASA wouldn't plan with an extension without good arguments for that. But I don't understand why they weren't pushing for a longer certification period earlier.

 

[.Scott]

NASA wouldn't plan with an extension without good arguments for that. But I don't understand why they weren't pushing for a longer certification period earlier.

I don't either. And I'm wondering whether the reason that Space Force hasn't put a quick kibosh to a 45-day extension is that after the next cryo test it could become a 65-day extension. NASA's been struggling with LH2 leaks for decades.

 

[mfb]

No official word yet, but I have heard that there are two ways forward:

* They get the FTS extension, launch September 27 or October 2, if that doesn't work back to VAB for a launch not before the November 12-27 launch window.
* They don't get the FTS extension, back to VAB immediately and maybe catch the launch window October 17-31.

Crew-5 is planned for October 3, so the October 2 launch date needs some extra coordination to prepare both rockets in parallel.

 

[.Scott]

No official word yet, but I have heard that there are two ways forward ...

Perhaps NASA's history with LH2 might steer you toward a more pessimistic launch date.

 

[mfb]

More delays are always possible, but these are time ranges where we can expect launch attempts at least.

 

[.Scott]

The fueling test is tomorrow: space.com
According to another website, work starts at 7:15am tomorrow.

 

[mfb]

Tanking test has started

The first components are being chilled down now.

 

[.Scott]

Tanking began at 9:09am ET. Hydrogen "Fast fill" is expected at about 10:30am. Completion at about 3:30pm.
So far, so good.

Hydrogen "Fast Fill" will start sooner. NASA reports that the Hydrogen temperature inlet sensor was not working - and that has affected the Liquid Hydrogen (LH) "Fast Fill" time. Apparently it was expected to start at 10:30am based on that faulty sensor. It is now expected to start earlier.

The LH Fast Fill is where the failure occurred during the last launch attempt - a couple of weeks ago. However, at this moment (10:02am), they are at LH "stop flow".

The LH "stop flow" was triggered by a hydrogen leak. The leak ended on "stop flow".

 

[mfb]

The LH "stop flow" was triggered by a hydrogen leak.

6 attempts to fill the rocket on the pad, 6 hydrogen leaks despite repairs between the attempts.

 

[.Scott]

6 attempts to fill the rocket on the pad, 6 hydrogen leaks despite repairs between the attempts.

At 10:13: The "leak team" has just reported to the launch director that the leak profile is identical to the leaks during those previous attempts. They will attempt to cycle temperatures in an attempt to better seat the connection. Next attempt around 10:45am.

 

[PeroK]

At 10:13: The "leak team" has just reported to the launch director that the leak profile is identical to the leaks during those previous attempts. They will attempt to cycle temperatures in an attempt to better seat the connection. Next attempt around 10:45am.

Why do things not work these days? Perhaps that's an unfair assessment?

 

[.Scott]

Why do things not work these days? Perhaps that's an unfair assessment?

NASA has never "mastered" LH fueling - in the sense that they can created results that matched the design intent on the first try.
In this case, the NASA live coverage is reporting that today's fault is identical to the Quick Disconnect fault that happened on Sept 3rd.