NASA Space Launch System (SLS)

[NMaude]

It's good to see progress on the new RS-25E engines however is Aerojet-Rocketdyne going to charge an outrageous price for them?

 

[NMaude]

Well it looks like NASA getting ready to rollout Artemis-1 to LC-39B for the wet dress-rehearsal:

https://twitter.com/x/status/1501951581696135174

View: https://twitter.com/NASAKennedy/status/1501951581696135174?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1501951581696135174%7Ctwgr%5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fforum.nasaspaceflight.com%2Findex.php%3Ftopic%3D49381.240

 

[publiusr]

Can't wait for it to stand outside the building.

 

[NMaude]

Can't wait for it to stand outside the building.

I can't wait for it to lift off.

 

[Orionblamblam]

Can't wait for it to stand outside the building.

I can't wait for it to lift off.

Can't wait for it to be cancelled and the funds used for a better system.

 

[NMaude]

Can't wait for it to stand outside the building.

I can't wait for it to lift off.

Can't wait for it to be cancelled and the funds used for a better system.

The first four missions are likely to be flown anyway as they're already complete (Artemis-1), mostly complete (Artemis-2 and -3) or in early construction (Artemis-4).

On another note NASA has released an Artemis-1 rollout trailer:

 

[NMaude]

NASA has just released this on YouTube:

 

[NMaude]

I just found this short NASA video about the people working on Artemis-1:

 

[publiusr]

SLS was rolled out today-a lovely sight. I saw no bend there depite shuttle twangs...the cyrotest in Boca? There looks to be a slight bend below the chopsticks.

 

[FighterJock]

SLS was rolled out today-a lovely sight. I saw no bend there depite shuttle twangs...the cyrotest in Boca? There looks to be a slight bend below the chopsticks.

Great news publiusr, I cannot wait to see the launch of the SLS in May.

 

[sferrin]

SLS was rolled out today-a lovely sight. I saw no bend there depite shuttle twangs...the cyrotest in Boca? There looks to be a slight bend below the chopsticks.

What are you talking about?

 

[jeffb]

https://twitter.com/x/status/1504774092775436313

View: https://twitter.com/cbs_spacenews/status/1504774092775436313?s=20&t=BH_jnnD_SzT4Qk8jynKsAg

 

[FighterJock]

https://twitter.com/x/status/1504774092775436313

View: https://twitter.com/cbs_spacenews/status/1504774092775436313?s=20&t=BH_jnnD_SzT4Qk8jynKsAg

The picture with the SLS in fog makes the whole setting rather atmospheric.

 

[sferrin]

Not quite the spectacle of a Saturn V.

 

[FighterJock]

Not quite the spectacle of a Saturn V.

I would have to agree with you on that point sferrin, having seen the Saturn V at Kennedy Space Centre when I went to Florida on holiday back in 1994.

 

[jeffb]

Another nice shot of SLS sitting on the pad.

https://twitter.com/x/status/1504866162806558724

View: https://twitter.com/wapodavenport/status/1504866162806558724?t=WJpU9TiM77XiVUl4Te6fFg&s=19

 

[publiusr]

Saturn V was a very busy design…all the more impressive due to its era.

SLS is stage-and-half. The Delta IV upper stage now a few facto insertion stage. Less busy, and better looking to me at least than most other LVs. Delta III was the ugliest thing that ever sat on a pad.

 

[jeffb]

Saturn V was a very busy design…all the more impressive due to its era.

SLS is stage-and-half. The Delta IV upper stage now a few facto insertion stage. Less busy, and better looking to me at least than most other LVs. Delta III was the ugliest thing that ever sat on a pad.

Really demonstrates the power (and utility) of those solids though. Not really sure I like them still. I'm just biased towards liquid propulsion I think.

 

[FighterJock]

Saturn V was a very busy design…all the more impressive due to its era.

SLS is stage-and-half. The Delta IV upper stage now a few facto insertion stage. Less busy, and better looking to me at least than most other LVs. Delta III was the ugliest thing that ever sat on a pad.

Really demonstrates the power (and utility) of those solids though. Not really sure I like them still. I'm just biased towards liquid propulsion I think.

If the SLS was all liquid propulsion it would have to be the tallest rocket ever built, I think that is why NASA has gone with the solid rocket boosters, though I was like you jeffb, I did not like the boosters much myself in the beginning.

 

[publiusr]

I wanted the Pyrios LFBs. Two F-1s apiece.

That is what Vulcan should have been: dial use as SRB replacement…J-2 upper stage.

Go after Musk with low part count. Maybe a Pyrios fly-back. Instead Bezos will gladly bring you engines Tuesday for a lawsuit today.

 

[martinbayer]

One of the Shuttle solid boosters boosters took down Challenger. To me putting crewed missions yet again on any launch vehicle that includes solid stages after that horrific accident is an absolutely incompetent abomination. Go Elon.

 

[NMaude]

I wanted the Pyrios LFBs. Two F-1s apiece.

It would've been interesting to see the SLS use two Pyrios boosters instead of SRBs.

 

[Rhinocrates]

Pigs might not fly, but the SLS is made of pork.

Um, anyway, I'll fetch my coat...

 

[publiusr]

Webb was expensive and delayed too. Ironically…had SD HLLVs flown earlier…it could have been simpler.

Starship may get LUVIOR…or it may not.

 

[NMaude]

I was checking over at NASA's Heavy Lift Launch forum and there's an update on the Artemis-2 first-stage:

https://twitter.com/x/status/1506016961485946880

View: https://twitter.com/ThePrimalDino/status/1506016961485946880?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1506016961485946880%7Ctwgr%5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fforum.nasaspaceflight.com%2Findex.php%3Ftopic%3D54249.0

The only outstanding item to be mated is the stage's thrust-structure (I thought the thrust-structure and the LH2 tank mated first).

 

[jeffb]

Rather nice infographic I came across comparing SLS and Starship.

 

[FighterJock]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

 

[jeffb]

Yep. Every time I look at it. Have they test fired it yet?

 

[sferrin]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

 

[sferrin]

Pigs might not fly, but the SLS is made of pork.

Um, anyway, I'll fetch my coat...

You can definitely see who the government-approved darling is. Just compare the coverage in the national media of SLS vs Starship, despite the fact that Starship is light-years ahead in technology, capability, and cost.

 

[FighterJock]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

Let's hope that Starship rocket does not fail on it's first launch like the Soviet N-1 did, that was truly spectacular having seen videos of the N-1's demise on YouTube.

 

[sferrin]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

Let's hope that Starship rocket does not fail on it's first launch like the Soviet N-1 did, that was truly spectacular having seen videos of the N-1's demise on YouTube.

The Starship tests suggest their may be failures. You dust yourself off and move on.

 

[Flyaway]

Pigs might not fly, but the SLS is made of pork.

Um, anyway, I'll fetch my coat...

You can definitely see who the government-approved darling is. Just compare the coverage in the national media of SLS vs Starship, despite the fact that Starship is light-years ahead in technology, capability, and cost.

Yeah because of course Starship has had no coverage at all. Your argument would hold some water if it had any basis in actual reality whatsoever. I’d say in the public that Starship and SLS are probably equally well known helped by Space X huge name recognition. You do Space X no credit at all by continually trying to cast them as some small scale company company crushed under the government boot, rather than what they are in reality which is probably now the globally dominate private launch provider owned by one of the richest men in world. The WSJ had an article today on NASA’s moon landing plans and was that illustrated with SLS, no it was illustrated with a picture of Starship.

 

[NMaude]

NASA has released a blog concerning the upcoming wet dress-rehearsal:

In a pre-test review on March 28, NASA gave the “go” to proceed with the Artemis I wet dress rehearsal scheduled for April 1-3. The approximately two-day test will run the Artemis I launch team through operations to load propellant into the rocket’s tanks, conduct a full launch countdown, demonstrate the ability to recycle the countdown clock, and also drain the tanks to give them an opportunity to practice the timelines and procedures they will use for launch.

During the rehearsal, controllers will countdown to T-1 minutes and 30 seconds and pause to demonstrate the ability to hold for up to 3 minutes, then resume until 33 seconds before when launch would occur, then pause the countdown. Then they will recycle back to ten minutes before launch and conduct a second terminal countdown to approximately 9.3 seconds before launch, then end the countdown. Sometimes called a “scrub,” launch controllers may decide not to proceed with launch if a technical or weather issue arises during or prior to the countdown. At the end of the test, the team will drain the propellant to demonstrate the procedures that would be used during a launch scrub. After draining the tanks, the team will review the test data before setting an official target launch date.

NASA will provide a live video stream of the rocket and spacecraft at the launch pad beginning at Noon EDT on April 1 on the Kennedy Newsroom YouTube channel. In addition to updates on this blog, NASA also will provide operational updates on the Exploration Ground Systems Twitter account.

 

[Richard N]

https://www.reddit.com/r/SpaceXMasterrace/comments/tr6r3q

View: https://www.reddit.com/r/SpaceXMasterrace/comments/tr6r3q/leaked_image_of_nasa_developing_its_plan_to_get/?utm_source=share&utm_medium=web2x&context=3

 

[jeffb]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

Let's hope that Starship rocket does not fail on it's first launch like the Soviet N-1 did, that was truly spectacular having seen videos of the N-1's demise on YouTube.

The Starship tests suggest their may be failures. You dust yourself off and move on.

Yeah, 33 Raptors seems a lot to throw away on a test, but hey, it's not my money.

A short browse around youtube suggests they've only done a test fire of the super heavy with 3 engines simultaneously. Still, they're not stupid and they do know what happened with the N-1. Hopefully they've designed at least some of those issues out in the super heavy.

You'd still think they'd test run it though.

 

[sferrin]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

Let's hope that Starship rocket does not fail on it's first launch like the Soviet N-1 did, that was truly spectacular having seen videos of the N-1's demise on YouTube.

The Starship tests suggest their may be failures. You dust yourself off and move on.

Yeah, 33 Raptors seems a lot to throw away on a test, but hey, it's not my money.

Do you know of another way to test fire 33 Raptors simultaneously without test firing 33 Raptors simultaneously?

 

[jeffb]

Anyone else have the same thought that the Raptor engine cluster on the Starship looks uncannily like the engine layout on the Russian Moon rocket that failed to get to the moon during the Apollo era.

How many ways are there to arrange 33 engines efficiently within a circle? We're not implying that, since the engine arrangement is similar, that this will fail like a half-century old rocket did, are we?

Let's hope that Starship rocket does not fail on it's first launch like the Soviet N-1 did, that was truly spectacular having seen videos of the N-1's demise on YouTube.

The Starship tests suggest their may be failures. You dust yourself off and move on.

Yeah, 33 Raptors seems a lot to throw away on a test, but hey, it's not my money.

Do you know of another way to test fire 33 Raptors simultaneously without test firing 33 Raptors simultaneously?

There has been a test firing of Super heavy with 3 raptor engines. There has NOT been a test of all 33 raptor engines fired simultaneously...yet. This was my point.

There doesn't seem to be any announcements of a test firing, just of a Super Heavy launch in the near future.

 

[publiusr]

Water-hammer a potential problem?

 

[jeffb]

Water-hammer a potential problem?

Pogo-effects, yes. From memory that's what did in the N-1, they couldn't keep the propellant flow even to all the engines, some of them started surging, it tore the bottom out of the stage. That's my memory of it, could be wrong.

Similar thing almost got Apollo 13 too.

With the added mass for Apollo 13, the pogo forces were suddenly a magnitude greater in intensity. A mission report said that the engine experienced 68g vibrations at 16 hertz, flexing the thrust frame by 3 inches (76 mm).

Woodfill said that if the center engine had continued running a few more seconds, the oscillations may have destroyed the vehicle. “That engine was pounding horizontally up and down, a quarter foot, at the rate of 16 times a second,” he said. “The engine had become a two ton sledge hammer, a deadly pogo stick of destruction, putting enormous forces on the supporting structures.”

Although...

Modern vibration analysis methods can account for the pogo oscillation to ensure that it is far away from the vehicle's resonant frequencies. Suppression methods include damping mechanisms or bellows in propellant lines. The Space Shuttle main engines each had a damper in the LOX line,[3] but not in the hydrogen fuel line.