Johnbr
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NASA Space Launch System (SLS)
- Thread starter Johnbr
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So after two years of delays caused by Mr. Obama cancelling Constellation, we get...
...essentially the 2005 ESAS version of Ares V, with SSMEs for the core stage and an External Tank Diameter core stage; but now painted shiny white and black to try and get Apollo-era cachet.
NASA quickly realized how stupid throwing away $50 million dollar engines designed for reuse between 50 flights was back during Constellation; and they switched to RS-68, which was developed out of a 1980s/1990s effort to develop a simplified expendable SSME.
But then the fools at DIRECT started coming out of the woodwork, claiming that the ablative nozzle of the RS-68 would never work on Ares V with the heat from the SRBs....
...Never mind that they had base heating problems in Apollo, specifically the Saturn V base heating environment was so severe that each F-1 engine had to be covered in about 1,000+ pounds of insulation to work.
Later plans to ground launch S-II stages with SRB boosters (look, Ares V forty years early!), ran into this problem of base heating from SRBs, albeit with the J-2s. Their solution was to design a heat shield that would prevent the J-2s from being fried by the SRB heat.
Anyway, it gets so much better.
Where will the SSMEs come from for the Obama [tm] version of Constellation?
Link
I'm sure the museums who paid $50~ million for each Orbiter are loving the fact that they will get defaced artifacts with no SSMEs, but in fact replica SSMEs in the back.
Ultimately, I predict that SLS will be within schedules and budgets for about a year. Maybe it'll actually run a bit ahead of schedule; as:
Mainly I think due to the programmatic costs inherent in redesigning and rechecking everything when you go from the 3 x SSME boattail in the 70 ton version that will fly first, to the 5 x SSME base for the next spiral.
Some more minor points:
Why will this rocket with many of the same elements as Ares V, be affordable when Ares V wasn't according to Obama?
How will they affordably recreate the workforce, which was already laid off by this point? (A lot of shuttle related workers were laid off in late August).
It's just a way for Obama to get certain Senators off his butt, and to defuse the use of NASA as a weapon against him in 2012 in certain very important states.
Once he's re-elected, he can quietly let SLS die when it cost-implodes in Winter 2012/Spring 2013.
...essentially the 2005 ESAS version of Ares V, with SSMEs for the core stage and an External Tank Diameter core stage; but now painted shiny white and black to try and get Apollo-era cachet.
NASA quickly realized how stupid throwing away $50 million dollar engines designed for reuse between 50 flights was back during Constellation; and they switched to RS-68, which was developed out of a 1980s/1990s effort to develop a simplified expendable SSME.
But then the fools at DIRECT started coming out of the woodwork, claiming that the ablative nozzle of the RS-68 would never work on Ares V with the heat from the SRBs....
...Never mind that they had base heating problems in Apollo, specifically the Saturn V base heating environment was so severe that each F-1 engine had to be covered in about 1,000+ pounds of insulation to work.
Later plans to ground launch S-II stages with SRB boosters (look, Ares V forty years early!), ran into this problem of base heating from SRBs, albeit with the J-2s. Their solution was to design a heat shield that would prevent the J-2s from being fried by the SRB heat.
Anyway, it gets so much better.
Where will the SSMEs come from for the Obama [tm] version of Constellation?
Link
I'm sure the museums who paid $50~ million for each Orbiter are loving the fact that they will get defaced artifacts with no SSMEs, but in fact replica SSMEs in the back.
Ultimately, I predict that SLS will be within schedules and budgets for about a year. Maybe it'll actually run a bit ahead of schedule; as:
- A lot of tough/costly work on 5-Seg and J-2X was done under CxP, providing immediate boost to appearances of viability for SLS.
- The program would be in that phase of development that is cheapish
Mainly I think due to the programmatic costs inherent in redesigning and rechecking everything when you go from the 3 x SSME boattail in the 70 ton version that will fly first, to the 5 x SSME base for the next spiral.
Some more minor points:
Why will this rocket with many of the same elements as Ares V, be affordable when Ares V wasn't according to Obama?
How will they affordably recreate the workforce, which was already laid off by this point? (A lot of shuttle related workers were laid off in late August).
It's just a way for Obama to get certain Senators off his butt, and to defuse the use of NASA as a weapon against him in 2012 in certain very important states.
Once he's re-elected, he can quietly let SLS die when it cost-implodes in Winter 2012/Spring 2013.
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RyanCrierie said:
Keep in mind (you probably know this) that Obama canceled this rocket before. The only reason that NASA made the announcement today is because the Senate put the rocket back into the authorization bill. NASA leadership--representing the president--does not want it. They dragged their feet on producing a design. And the only reason that the SSMEs are back in there is because Congress pushed for them.
I've read a couple of news articles on this so far that I hope will be edited before they are final, because neither one of them mentioned that this is the same rocket that was announced five years ago, and neither mentioned that the only reason NASA is doing this is because of a few members of the Senate. So some additional money will be pumped to the proper states, but this is not a development program in any real sense.
The only thing that will change the current impasse is a change in political leadership, either in the White House, Congress, or both.
blackstar said:
And nothing has substantiatively changed between that rocket (Ares V) and this one, other than the clock being reset back to 2005; when Ares V was ET diameter and used SSMEs.
I believe the law called for STS elements to be used where practicable. That was a huge escape clause which went unused.
Byeman said:
The Saturn approach to such base heating issues encountered during development was to brute force their way through, whether with thermal insulation applied to the engines directly (F-1) or using a mixture of an extended heat shield and thermal cocoons (J-2 for S-II Ground Launch concept), rather than declaring such issues were impossible to surmount.
Byeman said:
There's a big difference between safing something for museum display, such as removing explosive bolts or squibs (which they had to do for the NASM's Do-335), or fabricating reproduction parts because the originals were lost somewhere or had deteriorated too badly for restoration purposes (Enola Gay, which sat outside for quite a long time), and deliberately taking major historical components of a valuable historical artifact and deliberately destroying them to save a couple bucks of money. (Removing all the orbiter SSME/MPSes so they can be expended on SLS Block I flights)
RyanCrierie said:
NASA is loaning the orbiters. No one it buying them. The money is for transport. NASA loans all its hardware and sometimes goes back a retrieves hardware for reuse. Skylab 2 donated lots of hardware for Spacelab. Enterprise donated avionics and systems for the other orbiters.
And you are wrong about your point.
a. It is not a big deal that the engines are being removed, they are not the original engines. So your "historical" point holds no water.
a. All shuttle engines are not being destroyed. There are just as many non flight ones around.
b. Even if NASA were to not used the SSME's, they would still be removed because with the non flight ones, they would be sent to more museums.
c. So as it is, the orbiters are going to be displayed with real nozzles but dummy powerheads and there also will be a full up engine for displace next to the orbiter.
So, a not completely intact orbiter is not a big deal, especially when it visually the same and there is an SSME for a closeup look, which is not possible in the orbiter.
Only anal people would care about it
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I hate to seem like such a killjoy, but those SSME's are never going to fly. They'll spend another 10-20 years in a warehouse before they eventually get shipped off to museums.
On Tuesday I was at a discussion about the current human spaceflight situation and one of the themes was that this may be the beginning of the end of American human spaceflight. We may be seeing the long slow death of the program. The people who were involved in the discussion were pretty knowledgeable and include names that frequently appear in the press. They were fully aware of the pending SLS announcement and they were not optimistic about its chances of ever flying.
On Tuesday I was at a discussion about the current human spaceflight situation and one of the themes was that this may be the beginning of the end of American human spaceflight. We may be seeing the long slow death of the program. The people who were involved in the discussion were pretty knowledgeable and include names that frequently appear in the press. They were fully aware of the pending SLS announcement and they were not optimistic about its chances of ever flying.
Hardware that was coming back after each mission, not expended.
Any SSMEs given to the SLS program will end up in the vincity of 30.2 deg N 74 deg W at the bottom of roughly 16,000 feet of water.
And the plan for SLS is to essentially expend pretty much the entire production run of available Block II SSMEs as a stopgap to save money and development costs before the "expendable" RS-25Es become available at some fuzzy undefined future point.
By the way, I can't believe you missed the big point about Skylab B, regarding historical authenticity, further undercutting your point.
In order to get Skylab B to fit within the new National Mall building, they had to get out the torches and other cutting implements to remove bits and pieces of it so it could fit into hall 114 at the Mall building; along with opening it up so that tourists could see the interior.
That enabled it to be preserved in a fully climate controlled environment; as opposed to being put outside to rot, or being cut up for scrap; so the damage served a useful purpose, similar to how the US Air Force Museum saved the XC-99 from destruction by carefully cutting it up with welding torches so the plane could be reassembled and restored at some future point (it was too large to move by land).
The proposed destruction of the Block II SSMEs serves no real practical purpose, other than for mythical cost savings -- because once the new "expendable" SSMEs are being built (I have serious doubts on that), quite a bit of money will have to be spent integrating the SLS stack with the new engines.
They're the engines that powered each orbiter's final flight; making them historic artifacts by themselves.
Currently, the plan is to destroy 26% of all flight capable SSMEs ever built, and pretty much every Block II ever built.
But that's OK, for they will make Replica Shuttle Main Engines (RSMEs) to fool tourists.
This argument makes no sense. About 46 flight ready SSMEs were built, and there are only three orbiters left, which leaves 37 to dispense to museums with nine left in the orbiters. Then there's the test/developmental SSMEs which are historic in their own right, so there's more than enough to go around to museums, even if we left the final flight engines installed in the orbiters.
You'd be surprised at how many people would care about it.
By the way, SLS suffers from "Lego Rocket Syndrome", AKA "DIRECT syndrome", in how they plan to start out with a 3 x SSME boattail, and then develop an all new 5 x SSME base for the evolved 130 ton vehicle.
And just maybe, maybe replace the SRBs with something else down the line.
Somehow this will all be done cheaply and not suffer unexpected cost overruns. :
Providing a reality check; the closest we ever got to an actual Lego Rocket; the INT-20 (S-IC/S-IVB) and INT-21 (S-IC/S-II) variants of the Saturn V, which mixed and matched already developed and completed stages would have cost the following in DDT&E/R&D costs at a minimum (reality likely would have seen costs go up):
$2.1 billion for the INT-20
$2.49 billion for the INT-21
Against this:
Completing the cancelled Titan IIIM and finishing up it's man-rating to allow lightweight CSMs to be launched into orbit would have cost $1.3 billion.
Space Shuttle SRB DDT&E/R&D costs from 1970-1978 were $1.158 billion, while SSME development costs from 1970-1978 were $3.1 billion.
(All dollar costs are in 2010 dollars, by the way).
And just maybe, maybe replace the SRBs with something else down the line.
Somehow this will all be done cheaply and not suffer unexpected cost overruns. :
Providing a reality check; the closest we ever got to an actual Lego Rocket; the INT-20 (S-IC/S-IVB) and INT-21 (S-IC/S-II) variants of the Saturn V, which mixed and matched already developed and completed stages would have cost the following in DDT&E/R&D costs at a minimum (reality likely would have seen costs go up):
$2.1 billion for the INT-20
$2.49 billion for the INT-21
Against this:
Completing the cancelled Titan IIIM and finishing up it's man-rating to allow lightweight CSMs to be launched into orbit would have cost $1.3 billion.
Space Shuttle SRB DDT&E/R&D costs from 1970-1978 were $1.158 billion, while SSME development costs from 1970-1978 were $3.1 billion.
(All dollar costs are in 2010 dollars, by the way).
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There's an active thread filled with ranting and raving over on NSF. I actually fail to see the point of getting worked up about this and endlessly debating it. We're at a stalemate and we'll be in stalemate until at least January 2013. Nothing anybody says on the internet is going to change anything about this.
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Ranting and raving is an understatement. I actually subscribe to that site and I can't at the moment understand why. : I confess to not fully appreciating the reasons for the hate, aside from the SpaceX and DIRECT dweebs. Even so, the DIRECT guys got what they wanted -- a stake through the heart of Constellation -- so I don't know why they won't just accept victory and shut up.
I would have preferred that NASA specify a particular launch schedule to a particular orbit and a given total lift capability over say, a decade, and see what industry could have come up with. Appropriate safety and performance guarantees would need to be in place, of course, and access to facilities and technology would need to be provided via an SAA.
It isn't the process I would have preferred and it isn't the booster I would have chosen, but we have a new program and I for one hope that NASA is successful. They may not be, and if they don’t receive the correct funding they won't be, but some of that is out of NASA's hands. Hitting their performance targets and refusing to talk happy talk to the White House or the Hill is job 1 at the moment. When something is broken, own up to it. Keep credibility at all costs.
I confess to not fully appreciating the reasons for the hate, aside from the SpaceX and DIRECT dweebs. Even so, the DIRECT guys got what they wanted -- a stake through the heart of Constellation -- so I don't know why they won't just accept victory and shut up.I would have preferred that NASA specify a particular launch schedule to a particular orbit and a given total lift capability over say, a decade, and see what industry could have come up with. Appropriate safety and performance guarantees would need to be in place, of course, and access to facilities and technology would need to be provided via an SAA.
It isn't the process I would have preferred and it isn't the booster I would have chosen, but we have a new program and I for one hope that NASA is successful. They may not be, and if they don’t receive the correct funding they won't be, but some of that is out of NASA's hands. Hitting their performance targets and refusing to talk happy talk to the White House or the Hill is job 1 at the moment. When something is broken, own up to it. Keep credibility at all costs.
RyanCrierie said:
Which is OK because 74% of them will be saved. You show me where there is that high of a percentage of an aerospace system* product run is preserved where there were more than 10 units was built.
* Recovered manned spacecraft excluded.
Byeman said:
Imagine how many *more* museums could get a piece if they chopped 'em into confetti.
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GeorgeA said:1-Ranting and raving is an understatement. I actually subscribe to that site and I can't at the moment understand why. :
2-I would have preferred that NASA specify a particular launch schedule to a particular orbit and a given total lift capability over say, a decade, and see what industry could have come up with. Appropriate safety and performance guarantees would need to be in place, of course, and access to facilities and technology would need to be provided via an SAA.
1-Well, there's a lot of meat there. People post real documents (and not only in L2). But it's like so much of the space discussion--the same people making the same arguments that they have for years. You can go someplace like spacepolitics.com and find people posting and then dig in an archive and find the exact same people fighting with each other over the same things from 1998. If you stay out of certain threads on NSF you can increase your enjoyment. There's nothing to be learned about SpaceX, Direct, or SLS that has not been said a million times before, so stay away from those discussions.
2-There are reasons why the government doesn't do stuff like this. Space Act Agreements cannot be used for procurement, and they really limit the ability the government has to actually specify things. I talked to a NASA official a couple of months ago who expressed a lot of frustration with SAAs because he was concerned that he could not specify safety requirements and yet if the vehicle blew up and killed some astronauts, it was going to be NASA that got the blame.
So much of the public discussion of this stuff on boards and blog comments is taken in isolation, as if the rest of the federal government and federal law does not exist. People talk about Space Act Agreements, fixed-price contracts, cost-plus contracts, and the FAR as if they are experts when they have zero contracting experience and zero knowledge of how OTHER government agencies do stuff. (But they're Canadian or Australian and have a blog, so they're qualified to run the American civil space program.) I've always gotten a chuckle out of the prize advocates who suggest that NASA should just offer $10 billion to the first company that lands an American on Mars. They cannot point to a single other government agency that does anything remotely like that. They view all this stuff in isolation and believe that they're experts when they don't know how USAF or NOAA or the Marines or anybody else actually contracts for stuff.
Kevin Renner
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Is it just me but this looks a lot like Direct's Jupiter proposal. http://en.wikipedia.org/wiki/DIRECT
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Well, with the Shuttle gone, there is no need for the shuttle-specific structures. The clean-pad concept is similar to how Saturn was envisioned back in the day - move everything from the VAB out to the pad with the booster. This also gives (in theory) the opportunity to use multiple launchers on the same pad.
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GeorgeA said:
Yeah, but wasn't the pad knocked down because they didn't want to pay the maintenance costs? I don't think it is because they have a "clean pad" approach to anything.
They've cut it all down, but they're not planning on building anything on top of it.
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blackstar said:
Yes very true, but there is also the idea that the "next user" will be part of the develoment process for the replacement pad infrastucture -- perhaps NASA itself with the "21st Century Spaceport" or whatever the SLS KSC pie slice is called now. Or Elon, God help us all.
Matej
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RyanCrierie said:
This (probably) wont happen, because they are going to use SSME for the SLS rocket. According to the current plan, only SLS-7 and later will have new RS-25E engines in 2026. So the first six missions will use currently available SSME from the Space Shuttle, it means at least 18 examples.
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That's the justification. I'm not really sure that's the plan. I've harbored the suspicion for awhile now that one of the administration's goals has been to eliminate a lot of infrastructure, including facilities and people, because they view that as an impediment to proceeding. I won't argue if that is a good or bad idea, but you can find evidence in various policies.
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Excellent analysis.blackstar said:
What are the scenarios after 2013?
I guess the economic situation can be quite different compared to today too...
It seems US human spaceflight infrastructure and capability planning has been dysfunctional on a strategic level for decades.
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mz said:
(How do I write the sound a person makes when shrugging their shoulders and exhaling loudly? It's the sound equivalent of "Heck if I know!")
Nobody knows how the election will go. It's unclear if Obama will be reelected, and if not, who will beat him. If we do get a new president, however, expect another blue ribbon commission to address the issue of human spaceflight policy. And it's not easy to figure out what they might say--we could go down a certain path for the next 15 or so months that might really restrict the options they look at. It's unclear what is going to happen in the near-term. (There are certainly people out there who claim that SpaceX could fix everything in a couple of years if just given the money, but that seems really optimistic and based upon little data; a few launches is not the same as a proven launch vehicle and human spacecraft.)
Don't expect things to get any better in the short term. We're stuck where we're stuck. But the same is true about national politics, so nobody should be surprised.
OM
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NASA Moving Into Contract Mods For SLS (Aviation Week)
A related story: NASA Johnson Faces Competency Challenge (Aviation Week again)
A related story: NASA Johnson Faces Competency Challenge (Aviation Week again)
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Via spacedaily.com: The US will conquer deep space with Russian engines (RIA Novosti)
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Grey Havoc said:
No surprise to anybody who has worked this issue. A few years ago I ran a congressionally-mandated study on workforce issues for the then-Vision for Space Exploration. The question was how would NASA develop and maintain the required workforce skills so that they could undertake this new effort. Major challenges included anticipated attrition, such as retirements. Now they've got the opposite challenge--they face a lot of people being forced out or leaving out of frustration. They'll lose a lot of unique skills that don't exist anywhere else (and don't exist in the commercial space field).
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From Aviation Week:
Booster Competition For New NASA Heavy Lifter
Oct 7, 2011
By Frank Morring, Jr.
CAPE TOWN, South Africa — NASA plans to open a competition in December for multiple, 30-month contracts to study strap-on booster upgrades for the planned heavy-lift Space Launch System (SLS), including an upgrade for the five-segment, solid-fuel strap-ons baselined as the initial boosters for the big new rocket.
One challenge for NASA engineers will be to design an interface that can link different booster types to the SLS core stage, according to William Gerstenmaier, associate administrator for human exploration and operations. The SLS will be the vehicle NASA uses to send humans beyond low Earth orbit.
“Our vision is we’ll have an interface that’s generic, and we’ll be able to carry potentially different boosters and change them out as needed,” Gerstenmaier told a session of the International Astronautical Congress here Thursday. “So we could go compete in the future, maybe downsize if something’s easier for a mission that requires less thrust. We have some variability there, so if we do our job right, we’ll have the ability to change the boosters that sit on the side. That’s our ultimate goal. We’re not going to pick one.”
NASA plans to build a 70-metric-ton SLS at first, with only the core stage and strap-ons. The vehicle will grow to a 130-metric-ton capability with the addition of an upper stage and upgraded strap-on. The core stage will be powered by surplus RS-25D space shuttle main engines at first, followed by a throwaway version designated the RS25E. The upper stage will be designed to use the same tooling as the core stage, and will be powered by the J-2X engine now in testing at Stennis Space Center in Mississippi.
“If we don’t need an upper stage for certain missions, we don’t have to fly an upper stage,” he said. “We can just add it in for essentially marginal cost for the upper stage. We don’t have to add a new plant, new facilities and new tooling.”
The booster upgrade can be solid-fuel, liquid oxygen (LOX)/kerosene or LOX/liquid hydrogen, Gerstenmaier said. Only the first two SLS flights will be powered by the five-segment version of the space shuttle boosters that were originally developed for the first stage of the terminated Ares I crew launch vehicle.
“It turns out that to get to the 130 metric tons, we’re going to have to redesign the five-segment booster as well,” Gerstenmaier says. “We have to go to potentially a composite case, away from our steel case to save some weight, and we might need to make a propellant change to use the more energetic propellant that sits in the solid rocket motor. So even if we go continuous solids, we’re going to have to make a pretty significant change to the solid-rocket booster segment.”
The competition for an advanced booster will begin in December with study-contract bidding that is likely to include ATK, manufacturer of the current solid-fuel boosters, and a team that includes Aerojet, which has plans to upgrade the Russian-built AJ26 LOX/kerosene engine it modified for the Taurus II launcher that Orbital Sciences Corp. will use to send cargo to the International Space Station.
“We’re not really ready to step up to the booster activity right away with a full-up competition,” Gerstenmaier says. “We think there’s some technology that needs to get explored and understood as we go forward. We think we also need to define a little bit better the core interface with the solid rocket boosters or the liquid rocket boosters, so we have that as a design condition. So we’re going to have kind of a study phase, with potentially multiple contractors participating in that study phase for a period of about 30 months or so, and then we’ll roll right into the actual competition. But the idea is to have the new booster system available, probably in about the 2019 time frame.”
LINK
Booster Competition For New NASA Heavy Lifter
Oct 7, 2011
By Frank Morring, Jr.
CAPE TOWN, South Africa — NASA plans to open a competition in December for multiple, 30-month contracts to study strap-on booster upgrades for the planned heavy-lift Space Launch System (SLS), including an upgrade for the five-segment, solid-fuel strap-ons baselined as the initial boosters for the big new rocket.
One challenge for NASA engineers will be to design an interface that can link different booster types to the SLS core stage, according to William Gerstenmaier, associate administrator for human exploration and operations. The SLS will be the vehicle NASA uses to send humans beyond low Earth orbit.
“Our vision is we’ll have an interface that’s generic, and we’ll be able to carry potentially different boosters and change them out as needed,” Gerstenmaier told a session of the International Astronautical Congress here Thursday. “So we could go compete in the future, maybe downsize if something’s easier for a mission that requires less thrust. We have some variability there, so if we do our job right, we’ll have the ability to change the boosters that sit on the side. That’s our ultimate goal. We’re not going to pick one.”
NASA plans to build a 70-metric-ton SLS at first, with only the core stage and strap-ons. The vehicle will grow to a 130-metric-ton capability with the addition of an upper stage and upgraded strap-on. The core stage will be powered by surplus RS-25D space shuttle main engines at first, followed by a throwaway version designated the RS25E. The upper stage will be designed to use the same tooling as the core stage, and will be powered by the J-2X engine now in testing at Stennis Space Center in Mississippi.
“If we don’t need an upper stage for certain missions, we don’t have to fly an upper stage,” he said. “We can just add it in for essentially marginal cost for the upper stage. We don’t have to add a new plant, new facilities and new tooling.”
The booster upgrade can be solid-fuel, liquid oxygen (LOX)/kerosene or LOX/liquid hydrogen, Gerstenmaier said. Only the first two SLS flights will be powered by the five-segment version of the space shuttle boosters that were originally developed for the first stage of the terminated Ares I crew launch vehicle.
“It turns out that to get to the 130 metric tons, we’re going to have to redesign the five-segment booster as well,” Gerstenmaier says. “We have to go to potentially a composite case, away from our steel case to save some weight, and we might need to make a propellant change to use the more energetic propellant that sits in the solid rocket motor. So even if we go continuous solids, we’re going to have to make a pretty significant change to the solid-rocket booster segment.”
The competition for an advanced booster will begin in December with study-contract bidding that is likely to include ATK, manufacturer of the current solid-fuel boosters, and a team that includes Aerojet, which has plans to upgrade the Russian-built AJ26 LOX/kerosene engine it modified for the Taurus II launcher that Orbital Sciences Corp. will use to send cargo to the International Space Station.
“We’re not really ready to step up to the booster activity right away with a full-up competition,” Gerstenmaier says. “We think there’s some technology that needs to get explored and understood as we go forward. We think we also need to define a little bit better the core interface with the solid rocket boosters or the liquid rocket boosters, so we have that as a design condition. So we’re going to have kind of a study phase, with potentially multiple contractors participating in that study phase for a period of about 30 months or so, and then we’ll roll right into the actual competition. But the idea is to have the new booster system available, probably in about the 2019 time frame.”
LINK
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