so, Artemis test flight AKA Should Launch Someday, 16-Nov-2022

[maw lod qan]

I just read a report on a link (which I couldn't figure out how to copy) from American Space.

It was very interesting discussing all the if buts or ands they deal with.

The volume of LOX and LH2 made my head spin! They also discussed the SRB having a life span for use which surprised me.

Still dealing with the extension of the flight termination system  batteries being up to date.

One thing that did surprise me was the comment the trips from and back to the VAB stress the vehicle and they don't want to do it much.

The main comment was the cost of a failure is much more than a scrubbed launch. 

One of the proposed dates and time would be just around sunrise which would be spectacular!

Just might be another mad dash in my near future!

[DaveL59]

latest posted in the NASA blog on 12-Sep was: (subject to extension being granted of course)

Quote

 The agency will conduct the demonstration test no earlier than Wednesday, Sept. 21, and has updated its request for a launch opportunity Sept. 27, with a potential backup opportunity of Oct. 2 under review.

Specific times for the potential launch opportunities are as follows:

Sept 27: 70-minute launch window opens at 11:37 a.m. EDT; landing on Nov. 5
Under review – Oct. 2: 109-minute launch window opens at 2:52 p.m.; landing on Nov. 11

Artemis (nasa.gov)

[DaveL59]

nothing new in the NASA blog so far but CNN report that the cryo test will be Wednesday 07:15 EDT which will be live streamed. Interesting in their article was a note about the seals:

Quote

When engineers replaced the seal on an 8-inch (20-centeimeter) quick disconnect line for hydrogen, they found a “witness marker,” or indentation on the seal associated with foreign object debris, said Mike Sarafin, Artemis mission manager, at a Monday NASA press conference.

NASA's Artemis I moon rocket preps for prelaunch test | CNN

There was a press briefing earlier today, over here we'd likely have been watching the Queen's final journey

 

Edited September 19, 2022 by DaveL59

[DaveS]

Meanwhile, in Boca Chica

 

Edited September 19, 2022 by DaveS
Correct embedding

[Stu]

1 hour ago, DaveS said:

Meanwhile, in Boca Chica

 

Is it just me, or are those tanks not too close? I assume this was just a few engines firing too?

[DaveS]

I think it's a perspective effect, they are further away than they look. But yes, it is something of a concern as a fully fueled Starship / Booster could set them off it it went bang.

[DaveL59]

26 minutes ago, Stu said:

Is it just me, or are those tanks not too close? I assume this was just a few engines firing too?

nah it just adds to the show if it goes up in a big loud flash, he does like to showboat after all 😉 

[Astroscot2]

Just wait till they fire up all 33 😉  hopefully soon.....

[Guest]

On 18/08/2022 at 17:18, cajen2 said:

You know what it's called in the aviation industry: Boeing......Boeing.......Bong!

 

Its Boeing..... Boeing..... BOOM 

[DaveL59]

for those interested, cryo test underway

https://blogs.nasa.gov/artemis/2022/09/21/launch-director-gives-go-to-begin-cryogenic-operations-nasa-tv-coverage-underway-2/

[DaveL59]

oh dear, slo fill LH2 on stop as they have a leak at the umbilical join, deciding if to try the heat and retry procedure. Oh and a flaky temp sensor on the LH2 fill side too that's part of the fast flow switchover.

Edited September 21, 2022 by DaveL59

[DaveL59]

Well they did manage to get it all gassed up, had to manage the feed pressure on LH2 as it still leaked but at a low enough level to continue. Also had an issue feeding the upper stage later on so it seems LH2 is a bit of an achilles heel for them. In the end tho it's declared a successful demo so now we wait to hear the next confirmed launch date.

[malc-c]

5% leak, so a single percentage over the acceptable threshold.  So many on the chat of NASA Spaceflights stream was coming up with alternate meanings for SLS - most along the "slightly leaking spacecraft" or similar vein.   At this rate, given SpaceX's success of lighting both all 6 raptors on starship and 7 on Booster 7 in one week, Elon will be walking on Mars by the time the problems with SLS are resolved and gets launched ! 

[DaveL59]

remains to be seen of course if the next try will be a repeat of the last aborted launch - small leak becomes uncontrollable leak. That they had LH2 issues on the main and upper stages makes you wonder if there's a design or build issue with the quick disconnect couplings.

[Gfamily]

The shame is that if NASA had been able to design the SLS from the ground up, it is quite possible that it would already be around the Moon. 

It seems to me that the Senate imposed obligation to reuse Shuttle engines and technology is what's causing a lot of the problems.   

[malc-c]

12 minutes ago, Gfamily said:

The shame is that if NASA had been able to design the SLS from the ground up, it is quite possible that it would already be around the Moon. 

It seems to me that the Senate imposed obligation to reuse Shuttle engines and technology is what's causing a lot of the problems.   

I agree.  Silk purse / sow's ear comes to mind.  Given the time frame to get where SLS is today may have been quicker if the rocket was designed from the ground up.  But then it probably would have cost three or four times the budget and unlike Apollo where the drive was more political than scientific would never have got the backing.  I don't remember the space shuttle having any similar leaks when fuelling with liquid hydrogen, so maybe they should have used the same design (assuming the same parts could be used) .  Conversely if they have used the same parts and they knew the design of the seals had issues then what did they expect when it was used on the SLS... 

[DaveL59]

Ah but shuttle was different, in that the external tank was fuelled via the shuttle using the quick-disconnects in the tail of the shuttle. Those same lines from the external tank then fed the main engines on the back of the shuttle. So in effect for SLS they've grafted the ass-end of shuttle + 1 extra engine onto the base of the tank and stretched it for more capacity and so had to do something else for gassing the tank up.

[malc-c]

3 hours ago, DaveL59 said:

Ah but shuttle was different, in that the external tank was fuelled via the shuttle using the quick-disconnects in the tail of the shuttle. Those same lines from the external tank then fed the main engines on the back of the shuttle. So in effect for SLS they've grafted the ass-end of shuttle + 1 extra engine onto the base of the tank and stretched it for more capacity and so had to do something else for gassing the tank up.

So if they effectively used the same parts, then we would assume that on the shuttle they were leak proof then... I mean you wouldn't want evaporating hydrogen leaking just feet away from an ignition source (like three engines and two SRBs !) - In fact I would go as far as saying that the shuttle was more problematic as not only did you have the quick disconnect to load propellent but also the similar quick disconnects between the external tank and shuttle that fed fuel to the three engines.  I don't recall the shuttle having the same issues the SLS has.  

Don't get me wrong... I was really disappointed when the launch attempt was aborted.  I can't wait to see man back on the Moon, and given modern 4K and 8K cameras the video that will be sent back will be amazing.  But these setback are things that should have been checked and tested before being assembled and fitted.

[DaveL59]

they did have a number of LH2 leaks in fact with launch delays and even launched one that had a smell of gas inside after the leak was supposedly sorted. So maybe its just something about how to handle LH2 in fuelling or some other way needs to be determined. I'd imagine if they're hoping to generate LOX and LH2 on the moon to fuel boost more distant missions they're gonna have a lot of fun with the much sharper edged moon sand/dust that may find its way onto/into the fuelling lines and couplings... 

[Ags]

To be fair, H2 is very leaky stuff. It's the smallest molecule after all. And it is a strong greenhouse gas. One of the downsides  of a hydrogen economy.

[DaveL59]

I do wonder if the Smithsonian channel on Sky have some insider info tho, lately they're showing a series calls "Space Disasters". Fortelling the future, maybe? 😉 

[Stu]

7 minutes ago, DaveL59 said:

I do wonder if the Smithsonian channel on Sky have some insider info tho, lately they're showing a series calls "Space Disasters". Fortelling the future, maybe? 😉 

How is your Mars rocket coming along Dave? 😉😉

My apologies. It just feels the easiest thing to sit and criticise these guys and gals who are putting their all into achieving something pretty tricky, whilst also being shackled by the limitations of decisions made by their political masters.

I remain of the opinion that although SpaceX is new and shiny and exciting, they have a heck of a way to go with their Starship. They have not tested the full engine configuration, made it to orbit, re-entered from orbital speeds, landed the booster, landed the booster back on the pad to be gripped by the chopsticks and many other things. They will get there, we know that, but having seen how many explosions there were before nailing the landing of the small upper section of the Starship, I believe there are many huge challenges to be faced that will take time to work through.

I will stick my neck out and say I reckon Artemis will get to land on the Moon first..... at least without exploding 😱😱😂😂.

[DaveL59]

13 minutes ago, Stu said:

How is your Mars rocket coming along Dave? 😉😉

My apologies. It just feels the easiest thing to sit and criticise these guys and gals who are putting their all into achieving something pretty tricky, whilst also being shackled by the limitations of decisions made by their political masters.

 

no worries Stu, in fact it wasn't a criticism more a tongue-in-cheek remark as I'd happened to be in the TV guide a few mins earlier and that came up as I scrolled along. Made me giggle so figured I'd share 😉 

Agree re the moon, and from the tests so far there's no way I'd want a ride in his almost wingless tin can. Makes you wonder the odds of a good landing if there's a gust of wind...

As for my own rocket developments, well I can't exactly go to market for the exotic chemicals etc now given my new employer would take a very dim view of such activities, not to mention the landlord would quickly kybosh that anyway 😄 

Edited September 23, 2022 by DaveL59

[malc-c]

1 hour ago, Stu said:

How is your Mars rocket coming along Dave? 😉😉

My apologies. It just feels the easiest thing to sit and criticise these guys and gals who are putting their all into achieving something pretty tricky, whilst also being shackled by the limitations of decisions made by their political masters.

I remain of the opinion that although SpaceX is new and shiny and exciting, they have a heck of a way to go with their Starship. They have not tested the full engine configuration, made it to orbit, re-entered from orbital speeds, landed the booster, landed the booster back on the pad to be gripped by the chopsticks and many other things. They will get there, we know that, but having seen how many explosions there were before nailing the landing of the small upper section of the Starship, I believe there are many huge challenges to be faced that will take time to work through.

I will stick my neck out and say I reckon Artemis will get to land on the Moon first..... at least without exploding 😱😱😂😂.

Stu,   IF we are comparing the two, SpaceX have done a lot more than NASA.  Granted the full stack of booster and starship have yet to be launched, but SpaceX have launched and landed a starship without it falling over or RUD'ing  along the way.  They have repeatedly test fired the raptors, and now with plan on testing all 33 engines within the next month when starship 25 is stacked on top (one of the channels on YT mentioned that it needed the added weight of a fuelled starship to prevent the booster from ripping itself off the pad if it was tried without.)   - And if all goes to plan following an announcement by Musk that barring red tape they will be ready to do the first orbital flight by the end of November.

But I would agree that in reality SLS/Artemis will get to the Moon first.  All they need to do is launch what's standing on pad 39B.  Whilst un-manned it is planned to reach and orbit the Moon, which for SpaceX is some time away assuming the planned orbital flight is a success.  It would be fantastic to see the booster get caught in the chopsticks and starship land, or splash down without issue, but my gut feeling is that the booster will end up taking out the tank farm on its return.  They then have to launch two starships and perform a refuelling operation in orbit before setting off for the moon...  So it could be a year or two before SpaceX reaches that goal  

[Stu]

1 minute ago, malc-c said:

Stu,   IF we are comparing the two, SpaceX have done a lot more than NASA.  Granted the full stack of booster and starship have yet to be launched, but SpaceX have launched and landed a starship without it falling over or RUD'ing  along the way.  They have repeatedly test fired the raptors, and now with plan on testing all 33 engines within the next month when starship 25 is stacked on top (one of the channels on YT mentioned that it needed the added weight of a fuelled starship to prevent the booster from ripping itself off the pad if it was tried without.)   - And if all goes to plan following an announcement by Musk that barring red tape they will be ready to do the first orbital flight by the end of November.

But I would agree that in reality SLS/Artemis will get to the Moon first.  All they need to do is launch what's standing on pad 39B.  Whilst un-manned it is planned to reach and orbit the Moon, which for SpaceX is some time away assuming the planned orbital flight is a success.  It would be fantastic to see the booster get caught in the chopsticks and starship land, or splash down without issue, but my gut feeling is that the booster will end up taking out the tank farm on its return.  They then have to launch two starships and perform a refuelling operation in orbit before setting off for the moon...  So it could be a year or two before SpaceX reaches that goal  

Don’t get me wrong, I think the Falcon and Falcon Heavy are awesome, the technology and control systems involved are incredible. I won’t ever forget seeing the two ‘heavy’ boosters landing together after their twin sonic booms.

I just can’t help thinking that what they are attempting with the Starship is a whole other level of complexity. There may well be unforeseen issues with the 33 engines and managing the gimbling of the central engines (number?), and I don’t think they have managed the landing accuracy needed for the chopsticks to succeed with the Falcon boosters, let alone landing the huge StarShip booster accurately enough. I totally agree that it is likely to take out a whole load of infrastructure the first time they attempt a landing. Could make any previous explosions seem like small beans! 🚀🚀🔥🔥💥💥