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[New] Space Launch System / Orion Discussion Thread


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And some people still seem to think SLS is the next best thing since Saturn V. It's not. It's a white elephant: Impressive. Expensive. It eats a lot - does very little.

Also, this failure means another delay - who knows how long. Meanwhile, new administration is about to move into White House. Anyone who followed the news about NASA programs knows what does that most likely mean.

Policy changes.

Cost cutting.

Cancellations.

Wasted time and money.

And last but not least - a lot of very salty space nerds :rolleyes:

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I wonder if they are still going to push for a 2024 landing in the media? That was definitely the nail in the coffin for that happening. What does that mean for the boosters that had to launch within a year?

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I'm trying to look on the positive side here.  They must have got some decent data from the test and they had a good start up of all four engines plus a safe shutdown after the MCF (and better an MCF than an RUD). Also if this were a test by A.N. Other Space Company Inc., I'd be a fully paid up member of the 'this is why we test!' crowd, so its unreasonable and unfair not to be in that same place for SLS.

But - with all that said, it's the prospect of a lengthy delay before the next test which makes my heart sink. (I presume there will have to be another test after a component failure, for all the good data they got?) I'm hoping they can figure this out quickly, do whatever follow up tests they need to do and keep this on track so that those SRBs don't go out of date before they can stack the whole system.

Hoping...

Edited by KSK
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This was a validation test though, not a development test. It was supposed to be right first time and this programme is not hardware-rich. They can't just swap in the next engine or the next booster stage.

At worst, if this needs a redesign of the engine bay the programme may not survive.

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2 hours ago, KSK said:

 Also if this were a test by A.N. Other Space Company Inc., I'd be a fully paid up member of the 'this is why we test!' crowd, so its unreasonable and unfair not to be in that same place for SLS.

Other Space Companies would be prepared for failure. Surplus engines ready - if not whole another propulsion core ready to take over. With SLS what we see is what we get. To say bluntly - there is no slack in the system. No safety margin.

As of now, we'll get months long investigation of what went wrong. Then months of deciding what needs to be fixed. Then months of rebuilding the hardware. Then what - another Green Run? What if something else breaks?

Yes, I am a very salty space nerd. There is already precious little money spent on large scale space exploration (outside of Earth's orbit, i mean). It pains me to see good chunk of these money wasted on a program that looks mostly like a PR stunt.

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According to the press conference earlier yesterday, Stennis has several backup engines to swap out on-site. According to the director, that could take about 15 days, leaving margin still for a 2021 launch. So while the tank sections aren’t replaceable, the engines can be interchanged.

Although SLS hasn’t had the best development process, it’s useful to remember that with traditional systems, the kind NASA has to cover their ass with unlike a private company, delays are to be expected. The Saturn V had major issues before it was the reliable launcher it became. The Space Shuttle was meant to fly in 1977. Although SLS shares a large amount of commonality with the Shuttle stack, a large amount of stuff is new, like the new core stage, 4-engine configuration, 5-segment SRBs, the ICPS and EUS, not to mention an entirely new crew capsule. 5 years of delays? Maybe not a good sign for management. But now that we have it (almost) ready, I say use it.

Much has been said in this thread about SLS’s uselessness, limited applications, and high cost. But it fills a core part of the Artemis program that nothing else can do. It’s the only thing than can send Orion to NRHO, save some very odd Falcon Heavy-ICPS configurations. It will be the best way of  launching heavy cargo to LEO to make an MTV (I remain a Starship to Mars skeptic). It will launch science missions like Europa Clipper. It can and will evolve, as we already see with BOLE boosters and EUS, as well as possibly Pyrios. It is being manufactured for cheaper with RS-25E and soon RS-25F main engines.

SLS will be the only way for crew to access the moon for a long time, even if MoonShip pans out, it will not make sense given how Starship development has gone compared to prior expectations to launch people to NRHO solely on Starship.

Is SLS the best architecture for return to Luna? No. Is Starship? No. I would have chosen a plan with something like a cross between EDS and ACES. But SLS is what we have for the time being, so we should get used to having it as our launch vehicle for human Lunar access.

It’s not a paper rocket either, we’ve got a ton of flight hardware in the public eye, despite the long time it took to make that stuff.

 

Edited by Clamp-o-Tron
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6 minutes ago, Clamp-o-Tron said:

It will be the best way of  launching heavy cargo to LEO to make an MTV (I remain a Starship to Mars skeptic).

Even if Starship ends up never launching anything to Mars, what's stopping it from being used to build a vehicle in LEO instead? It certainly seems like a better option than SLS - 1 year between launches means it'll take several years to complete, and by the time your MTV is ready to go all of its propellant will have boiled off.

10 minutes ago, Clamp-o-Tron said:

It will launch science missions like Europa Clipper.

Only if it's available, and with SLS's timeline slipping further that's looking less and less likely. 

12 minutes ago, Clamp-o-Tron said:

It can and will evolve, as we already see with BOLE boosters and EUS, as well as possibly Pyrios.

By the time any evolution that will make SLS useful for anything other than sending Orion to a distant lunar orbit is ready (like EUS), other options will be available. EUS is a long way away, and Block II is basically dead.

16 minutes ago, Clamp-o-Tron said:

SLS will be the only way for crew to access the moon for a long time, even if MoonShip pans out, it will not make sense given how Starship development has gone compared to prior expectations to launch people to NRHO solely on Starship.

What do you mean by this? Starship development seems to have gone pretty well thus far. Obviously it won't be ready to launch crew before SLS, but I doubt it will be a long time before Starship and/or other vehicles are ready to take humans to the Moon.

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5 hours ago, KSK said:

I'm trying to look on the positive side here.  They must have got some decent data from the test and they had a good start up of all four engines plus a safe shutdown after the MCF (and better an MCF than an RUD). Also if this were a test by A.N. Other Space Company Inc., I'd be a fully paid up member of the 'this is why we test!' crowd, so its unreasonable and unfair not to be in that same place for SLS.

But - with all that said, it's the prospect of a lengthy delay before the next test which makes my heart sink.

Well, you've spotted the problem yourself... They're not gearing this to be one with lots of failures. If they did, they'd have a dozen engines on standby or in production ready to be tested again in a few months at most. They'd also have more than one rocket core tank ready to be used or being built.

Problem at this point IMO is that the hardware is reeeally old - I don't mean that the tech is old, but the age of the materials itself is old as it has stood around for a long time. I'd rather them build one again from scratch at this point, make sure they're starting with fresh equipment. It's the same way that half-finished structures are often demolished instead after standing for a long time rather than being reused and just continued building on top of it, because you can't be sure that the ageing hasn't damaged the thing itself beyond what's supposed to be normal during construction phase.

2 hours ago, Clamp-o-Tron said:

Stennis has several backup engines to swap out on-site. According to the director, that could take about 15 days, leaving margin still for a 2021 launch. So while the tank sections aren’t replaceable, the engines can be interchanged.

Actually, are the engines used in the latest test is what remained from the last STS flight ? Or is it new engines ? I've heard that they do order new engines, but that was in May 2020 (24 new engines, 6 from 2015 then 18 being contracted) so I'm not sure if they'd be done by now.

EDIT : Alright yeah the plan was to use the Shuttle-left engines (here mentioned they have 16 left from the shuttle era)... I hope they'll change that now to the new engines since they're all 10 years old.

Edited by YNM
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I was texting back and forth with a buddy at MCC (who gets to work on Artemis when it actually flies). He's not a huge SLS fan, but wants to see it fly. He said, "At least it didn't explode." And while I agreed that was good, I followed with saying I have mixed feelings and a ;) .

I think they have trouble because the old way is presented as loads of testing, including all sub components, and loads of modeling. The tendency is to call the SpaceX way of doing integrated testing "very different" mostly because SpaceX does this faster, not because it's really that different. They all test, and finding problems is valuable when testing vs flight. If this had been a SpaceX test at McGregor, no one would bat an eye, and indeed no one would know other than "A huge rumble was heard for over a minute!" Yipee! The problem is that the SLOW contractors have created an alternate reality in PR where they do things very differently—and better. So when it doesn't work perfectly, there is a false impression of failure.

They'd of course not be in this problem if this test had been done 4-5 years ago, gunning for a 2016-2017 launch date.

 

 

4 hours ago, YNM said:

Problem at this point IMO is that the hardware is reeeally old - I don't mean that the tech is old, but the age of the materials itself is old as it has stood around for a long time. I'd rather them build one again from scratch at this point, make sure they're starting with fresh equipment. It's the same way that half-finished structures are often demolished instead after standing for a long time rather than being reused and just continued building on top of it, because you can't be sure that the ageing hasn't damaged the thing itself beyond what's supposed to be normal during construction phase.

Given that they have spent $127,000,000 on refurb for each engine, the engines should have mostly entirely new parts.

I was explaining the problem with SLS to my wife in a nutshell earlier, and I said that Shuttle derived vehicles were a great idea—while Shuttle was flying, and using unaltered Shuttle components (Shuttle C). As soon as they started changing... everything, they should have gone clean sheet.

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17 hours ago, .50calBMG said:

I wonder if they are still going to push for a 2024 landing in the media? That was definitely the nail in the coffin for that happening. What does that mean for the boosters that had to launch within a year?

2024 was obviously chosen because of the Presidential election cycle. That's no longer relevant, at least not in the same way it was when the goal was announced.

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I think Bridenstine was pitching to his bosses (successfully). The bottom line was that SLS/Orion was flailing, and without a focus. The ARM mission was an abject waste of time, just make-work for a system not really capable of anything. Giving it a goal with actual international support, and one that could use the increased capability of commercial space was pretty brilliant, even if the date was always "aspirational."

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23 minutes ago, tater said:

I think they have trouble because the old way is presented as loads of testing, including all sub components, and loads of modeling. The tendency is to call the SpaceX way of doing integrated testing "very different" mostly because SpaceX does this faster, not because it's really that different. They all test, and finding problems is valuable when testing vs flight. If this had been a SpaceX test at McGregor, no one would bat an eye, and indeed no one would know other than "A huge rumble was heard for over a minute!" Yipee! The problem is that the SLOW contractors have created an alternate reality in PR where they do things very differently—and better. So when it doesn't work perfectly, there is a false impression of failure.

I feel there's still one fundamental difference: the way the test was approached. As @RCgothic said previously, this was a validation test, not a developmental test as SpaceX is doing. It was meant to be right first time, and indeed we saw that the PR people on NASA's stream had no script for a early shutdown or other non-norminal outcome (they were calling it a successful test at the end of the stream despite it not reaching the minimum acceptable duration).

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6 minutes ago, RealKerbal3x said:

I feel there's still one fundamental difference: the way the test was approached. As @RCgothic said previously, this was a validation test, not a developmental test as SpaceX is doing. It was meant to be right first time, and indeed we saw that the PR people on NASA's stream had no script for a early shutdown or other non-norminal outcome (they were calling it a successful test at the end of the stream despite it not reaching the minimum acceptable duration).

Fair point.

But SN8 was a validation test, as a counter example. The difference is also that SLS is flight article because it's so bloody expensive.

In the Apollo days (what that test stand was actually built for, after all), they did the same testing—but they had more sausages churning out of the rocket factory to replace whatever the last test article was.

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1 minute ago, tater said:

But SN8 was a validation test, as a counter example. The difference is also that SLS is flight article because it's so bloody expensive.

Eh, I'd still call SN8 a development test. Unlike SLS, they were deliberately pushing the limits with a vehicle nowhere near a finalised configuration, and fully expected it to fail at some point. It did validate a lot of Starship's flight envelope, but only because it got a lot further than they were expecting and gave them a load of data, which they were prepared to throw right back into the next prototype. 

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5 minutes ago, RealKerbal3x said:

Eh, I'd still call SN8 a development test. Unlike SLS, they were deliberately pushing the limits with a vehicle nowhere near a finalised configuration, and fully expected it to fail at some point. It did validate a lot of Starship's flight envelope, but only because it got a lot further than they were expecting and gave them a load of data, which they were prepared to throw right back into the next prototype. 

Well, they are hardware rich, so they can do it. If they were only building ONE complete SS/SH to stack using all their money...

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1 hour ago, tater said:

Given that they have spent $127,000,000 on refurb for each engine, the engines should have mostly entirely new parts.

I was explaining the problem with SLS to my wife in a nutshell earlier, and I said that Shuttle derived vehicles were a great idea—while Shuttle was flying, and using unaltered Shuttle components (Shuttle C). As soon as they started changing... everything, they should have gone clean sheet.

Yeah. It's now been a whole decade since Shuttle stopped flying, so using anything derived from it is in a way like asking to do planning based on outdated data. There's no guarantee that it would remain working. Starting from clean sheet is better because at least you have to find the data first...

The reason why it was so expensive was probably partly because they were replacing parts on it (the RS-25 "D", that is the version that last flew with Shuttle) with new parts for the expendable version (RS-25 "E"). The other part I suppose is just examining and actually repairing (like welding etc) the thing, you can't automate them.

19 minutes ago, tater said:

But SN8 was a validation test, as a counter example. The difference is also that SLS is flight article because it's so bloody expensive.

Validation of the manoeuvre. There're still a lot to go for the whole stack, but by doing that they've come closer to being contracted for the mid-2020s lunar landing since 'all they need to add' are the vacuum engines, in-orbit habitation system, pressurized space, and man rating, plus the multi-engine first stage. (expecting the man-rating part to be the most time and resource consuming). For them to be contracted with the lunar mission they don't need to man-rate the first stage, so it's still in the horizon, as all they need is delivering an empty man-rated ship to orbit, then it'll take over from there.

47 minutes ago, mikegarrison said:

2024 was obviously chosen because of the Presidential election cycle. That's no longer relevant, at least not in the same way it was when the goal was announced.

I'd expect a slip to the last quarter of 2020s (so 2027-2029) - although if it hits 2030 I expect the domestic competitor to have been man-rated, plus I'm sure they'd be getting foreign competitors by then (hope that'd actually be a motivation boost...)

Edited by YNM
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It's actually in the interest of SLS to push harder to launch at this point.

As the jobs program it is, sans competition, the longer it takes the better. More money spent on the actual goal of SLS/Orion (jobs).

The trouble of course is that commercial space is going to lap SLS, and once that happens, it will become harder to justify. IMO Orion can probably survive longer than SLS as a program, since Orion can be stuck on top of NG (and possibly Vulcan, the mass is tight there with the LES).

 

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Having international partners joining in as well is pretty much a push, given at least how one of the partners they've listed now always delivers their point.

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7 minutes ago, YNM said:

Having international partners joining in as well is pretty much a push, given at least how one of the partners they've listed now always delivers their point.

The Moon is a goal that can actually be accomplished, and international partners are only contributing chump change, so it's a good deal for them. Get astronauts to the Moon for virtually zero cost.

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50 minutes ago, tater said:

It's actually in the interest of SLS to push harder to launch at this point.

As the jobs program it is, sans competition, the longer it takes the better. More money spent on the actual goal of SLS/Orion (jobs).

The trouble of course is that commercial space is going to lap SLS, and once that happens, it will become harder to justify. IMO Orion can probably survive longer than SLS as a program, since Orion can be stuck on top of NG (and possibly Vulcan, the mass is tight there with the LES).

 

Orion on top of an expendable Starship...?

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3 minutes ago, RCgothic said:

Orion on top of an expendable Starship...?

NG is to be "crew rated" from go according to all BO statements ever.

Vulcan as well, because Starliner.

Starship is not, so I'd say that would depend. Also, in this SLS/Orion thread I make a conscious point to not push Starship unless an SLS fan brings it up. The fact that SLS can be made pretty useless by "not SpaceX" is the critical bit here. No need to be a SpaceX fan to beat on SLS, SLS is just a poor design.

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