Chair Force Engineer has been reading the DIRECT rebuttal, and says that there are problems with both the RS-68 and the SSME has an upper-stage engine. One point that he doesn’t make, but is a major issue, is that the SSME is not currently capable of air (or vacuum) start. It currently needs a lot of ground support equipment. Even ignoring the manufacturing cost (which will be recurring every flight), requalifying the hot box for second-stage work will be a major program cost and risk.
Abandoning reusables because of the Shuttle and X-33 is nuts. It’s Wile E. Coyote engineering.
I think they are proposing SSME’s for the 1st stage, not air start.
I was commenting on use of SSME and RS-68 as core stage engines only. Although the ESAS assumption that SSME could be quickly adapted for upper-stages is another piece of evidence that the initial study was heavily flawed.
I really don’t know how NASA’s going to solve the issue of SRB heating on the core stage engines, but I get the feeling that the Augustine Commission will make their solution a moot point.
Actually, now that you mention it, that’s a promising idea.
We just need some ball bearings, a really BIG magnet, and a large rubber-band…
“Abandoning reusables because of the Shuttle and X-33 is nuts. It’s Wile E. Coyote engineering.”
Can you explain what you mean by that? Note that the DIRECT team claims the SSME has a high fixed cost and that unit costs will come down significantly once you start producing large numbers and improve the design for modern manufacturing techniques. Apparently it would then cost only slightly more than an RS-68.
Incidentally, this removes one of their objections against Shuttle-C, namely high engine cost.
Switching to SSME also increases payload and some have voiced suspicions that performance is the real reason, and that the base heating problem is being used as a smokescreen. If true, that means that not only is a big launcher unnecessary, they can’t even get it to work without SSME.
I mean that they try something, and it fails spectacularly, and rather than sit down and figure out what went wrong and try it again, they completely abandon it and try some entirely new thing.
And no matter how many SSMEs you crank out, they’re never going to be cheap, and marginal cost of an expendable flight is always going to be very high.
I’m inclined to believe them on the cost of the SSME, but I’m skeptical about the base heating issue. It’s all a bit convenient. But either way SSME seems like a better choice if there is going to be a Jupiter.
I hope you’re not suggesting NASA should have another go at developing a reusable launch vehicle? Let them build a depot and let the market build an RLV, or a cheap, unreliable and expendable launcher like Scorpius or Aquarius.
No, I’m suggesting that NASA get out of the launch vehicle business, and come up with an architecture based on what commercial launch services can provide, now and in the future, and let the market sort out the best way to get commodities and people to orbit.
Yeah, that would be best. I’m not optimistic about that though, and I believe a mostly harmless compromise is needed. DIRECT is not that compromise. Shuttle-C might be, or J-130 only, as long as it stays out of LEO.
My following of the Direct discussions at NSF suggests that the original plan to use the RS-68 (ablative) for both Ares V and Jupiter 232 will fail because of core heating.
Direct 3.0 (to be released next week) will switch to four (4) regeneratively cooled SSME – starting with the off the shelf flight proven SSME and later moving to a less expensive “disposable” version.
Since SSME offers highly isp (but lower total thrust) than RS-68 an SSME core stage also allows the use of RL-10s on the 2nd stage avoiding J2X development altogether.
The Direct 3.0 J-246 will use 2 “off the shelf” solids essentially identical to what shuttle uses today plus 4 SSME identical to what is used today with an upgrade path to a less expensive version plus 6 flight proven RL-10s for the upper stage.
This saves big dollars over Ares because of:
No 5 segment SRB development (Ares 1)
No 5.5 or 6 segment SRB development (Ares V)
No J2X development
No RS-68 regenerative development.
Ares V will need new SRBs (5.5 or 6 segment with new fuel grains and a composite casing); and
A new RS-68 (regeneratively cooled) engine for the core stage; and
A new J2X for the upper stage (Ares V and Ares 1) — J2X is needed if RS-68s are used in the core because of the lower isp of the RS-68.
In addition, Ares 1 will use a 5 segment SRB for a total of FOUR new engines to be developed versus ZERO new engines for Jupiter 246.
Develop an air-start SSME for Ares 1? From a standing start in Fall 2009? My reading is that it is far from certain that is feasible, at any price and would take YEARS at a minimum.
Direct offers very significant commonality with what already exists while ESAS offers essentially zero commonality.
= = =
Jon Goff has a point that NASA might be beyond salvation and that a total
“CTRL – ALT – DEL”
could be the “best” route forward
However that would require the investment of tremendous amounts of political capital and since George W. Bush plainly refused to take on that challenge, we cannot expect Barack Obama to take on that challenge, either.
THEREFORE, perhaps getting the Obama Administration to agree to facilitate a MirCorp II undertaking could enable NewSpace without doing a CTRL-ALT-DEL on all of NASA.
Over an adult beverage, this is worth considering . . .
No, I’m suggesting that NASA get out of the launch vehicle business, and come up with an architecture based on what commercial launch services can provide, now and in the future, and let the market sort out the best way to get commodities and people to orbit.
However, since George W. Bush was entirely unwilling to invest the political capital needed to accomplish this, it is unfair to expect Barack Obama to do this
(a bi-partisan “FAIL” as it were)
and therefore NewSpace needs a “Plan B”
But he’s so much better and braver than GWB! Just ask him!
Some more things to keep in mind regarding the SSME:
The improved performance of the SSME allows the DIRECT team to meet their performance targets using RL-10’s on the upper stage, thus making the J-2X unnecessary, which saves costs and reduces risk compared to Ares.
The SSME is of course also already man-rated. This gives DIRECT an edge over Delta-IV, which would no longer get its RS-68 man-rated for free. Conversely, they still propose man-rating the Delta-IV, but this would also man-rate the RL-10 which they plan to use on their upper stage for free, thus hiding the costs.
Because of this the DIRECT team can now argue for J-130 to be the initial launch vehicle for Orion, whereas initially they had expected Delta-IV to be operational sooner. They also want to launch some payloads that could easily be launched on an EELV. I think this demonstrates that they have no payloads for their supposed low cost/kg in the early years. Incidentally it also removes one of their advantages over Ares V: it would be operational sooner. No point in that if you have no payloads. In fact it is positively harmful, taking away business from commercial launchers.
Switching to SSME gives the DIRECT team a lot of advantages. It’s so convenient I suspect politics and jockeying for position with the EELVs is the main reason for the switch.
There is no such thing as a man-rated engine.
Martijn –
I recall reading that some on the Direct Team wanted to switch to SSME long ago but felt they couldn’t until ESAS “opened the door” by expressing a willingness to re-consider SSME for Ares V.
In part this was because of those hidden appendices and how horrifically more expensive SSME was alleged to be to produce in bulk versus RS-68. Apparently, the difference is less than advertised and if we factor in development costs for the RS-68 regen (and factor in avoiding J2X development altogether) SSME actually is quite the value.
The Direct presentation for ISDC is titled “Twice the Payload to the moon for Half the Price” (compared to ESAS)
If Jupiters are used delivering lunar infrastructure there will be plenty of ISS work for EELV such as Delta IV
Also, facilitating non-NASA destinations (LEO and/or EML) is another way to create more demand for new players and therefore NOW is the time to push the Obama Administration to create rules that would encourage a MirCorp II type of undertaking that would not be supported by any NASA operated vehicles.
I’m told that to be man-rated, engines need extra diagnostic measurements and logic to signal the LAS to get out of Dodge. And I thought man-rating a vehicle included man-rating the individual components as well as the system as a whole. At least this is what people at nasaspaceflight.com have been saying, and not just the DIRECT people. Can you say more?
There is no such thing as a man-rated engine.
Yes, but there is a difference between flight proven engines such as SSME and RL-10 and 4 segment SRBs
Compared with Powerpoint engines such as RS-68 (regen) or J2X or airstart SSME or 5 or 5.5 or 6 segment SRBs
So a man rated engine is one that blows up when the weather is cold? Good to know. No ability to shut down or restart? I had a Dodge with a broken throttle return spring that was man rated like that.
Bill,
I’m with you on the MirCorp II thing, but like Bigelow it would need a man-rated launcher and capsule to get people into space. Both EELVs should be man-rated as soon as possible and Falcon 9 as well and COTS-D should also be funded immediately. Not so much to close the infamous “gap”, although that is important as well, but to promote commercial development of space. This is of course part of NASA’s official missions and its importance has been reemphasised by the remit of the Augustine commission. This is made more difficult by funding J-130 at the same time and having it compete for payloads.
You are right that Ares reconsidering SSME made it possible for DIRECT to make the switch and that they might have wanted to do it all along. I think it is likely the correct choice of engine. But the politics behind it deserve more scrutiny.
Martijn writes:
I’m with you on the MirCorp II thing, but like Bigelow it would need a man-rated launcher and capsule to get people into space.
There are rumors that Mike Griffin called up top executives at Lockheed and shouted at them about the plans floated to deploy a privately developed Atlas V capsule to service a Bigelow LEO station
= IF = that rumor is true, I would be more angry about that than even the Ares 1 nonsense.
Obama can reverse that mentality without spending tax dollars or re-directing NASA’s budget. All he needs to do is give a speech expressing support for a Bigelow LEO station supported by private customers and tell his subordinates to NOT interfere.
You human-rate an entire system. It’s not meaningful to isolate a component out of it and call it human rated. I really, really wish that people would just stop using the phrase, because it’s really meaningless. We don’t human rate airplanes, and there’s no reason to do so with rockets. This whole issue wouldn’t even exist if we weren’t throwing the vehicle away.
I’m thinking unit testing vs integration testing vs system testing. Isn’t there something similar in the man-rating process? And maybe I’m using the wrong term, but isn’t it true that a vehicle intended for crew has to do more measurements, both of the engine and the structure, and has to have a way to trigger the LAS? And it may need to have higher factors of safety. All that requires making changes to an existing cargo-only vehicle. I think that’s what the DIRECT people mean when they say man-rating an engine. It’s not just having a committee of experts look at it and put their stamp of approval on it. So if that’s not called man-rating, what is the correct term for this?
Yes, a human-rated system has to have a Failure Onset Detection System. But guess what — a non-human-rated system does, too, for range safety.
There may be some additional things that need to be done to the RS-68 to meet this goal, but the SRBs don’t have anything like that. For instance, we never knew about the O-Ring blow through until post flight. The first hint that Challenger knew there was anything wrong was when they started to have to gimbal to compensate for the side jet, and that wasn’t enough of a hint to know what to do.
And of course, there was no abort capability prior to SRB separation, since they couldn’t be shut down (one of the reasons that the Shuttle was never man rated, which is why it’s absurd to declare that subsystems of it are).
Bill, Lockheed was asking NASA to fund their “privately developed Atlas capsule.” You don’t think they were going to build Orion Lite with their own money, do you? (If they were, it wouldn’t matter what Mike Griffin thought about it.)
When I keep hearing “Reusable”, are we talking -completely- reusable? I mean, I understand we’re talking about making the cockpit/upper parts much more reusable than the Shuttle is.
But are we talking about making everything reusable? The SRB’s seem (relatively) straightforward and are essentially spare parts afterwards. But they would seem to be the most cost efficient pieces of the whole lift.
IOW: What is the fuel-to-price ratio for a single SRB? And how would -that- be affected if we were using thousands a year? Because of all the pieces of a lift system, the solid fuel pieces would seem to be most amenable to a more mass-production approach.
Edward, that is not the rumor I read.
I read (in several places) a suggestion that Mike Griffin was very hostile to the idea that Lockheed would build an Atlas V capsule to service Bigelow in part because it would be deployed far sooner and cheaper than Orion and that Griffin threatened future contracts if Lockheed “showed up” NASA in that manner – which is why it mattered what Griffin thought.
IMHO, ending NASA’s monopoly by persuading Obama (and Hillary Clinton?) to promote and facilitate a MirCorp II would help create a market for NewSpace launchers; a bigger market – IMHO – than propellant depots sold fuel for NASA lunar missions.
Rotating tourists every 7, 10 or 14 days will require a great many flights for passengers and cargo and could provide flight rates sufficient to justisy a genuine RLV.
One link . . .
http://forum.nasaspaceflight.com/index.php?topic=11786.msg240397#msg240397
Yes, the rumor is hotly contested and yes if an Atlas V capsule were allowed to compete for COTS-D money that would assist the Lockheed Bigelow deal and yet there are allegations that Griffin’s alleged animosity towards Atlas V is linked to Lockheed wanting to do a private business deal with Bigelow.
But are we talking about making everything reusable?
Ultimately, yes.
The SRB’s seem (relatively) straightforward and are essentially spare parts afterwards. But they would seem to be the most cost efficient pieces of the whole lift.
Only for very low flight rates.
Edward, that is not the rumor I read.
That’s why they call them “rumors.” 🙂
Rotating tourists every 7, 10 or 14 days will require a great many flights for passengers and cargo and could provide flight rates sufficient to justisy a genuine RLV.
Yes, but that was never part of the Bush Vision of Space Exploration (and it remains to be seen if it’s part of Obama’s vision). Unfortunately, the Moonies and the Marsies continue to insist on architectures that are so expensive they wouldn’t leave NASA any money to do anything else.
Moonies, Marsies, where do you want to go?
*IMHO, ending NASA’s monopoly by persuading Obama (and Hillary Clinton?) to promote and facilitate a MirCorp II would help create a market for NewSpace launchers; a bigger market – IMHO – than propellant depots sold fuel for NASA lunar missions.*
Except that that speculative market is dependent upon it coming about through independent private financing and for there to be a valid business case for it to succeed, something that is not clear at this point in time and with the state of current space access. The NASA lunar payload demand is real compared to that speculative vision, and would provide a market several times the size of what the American launch industry currently caters to. Evolution of the state of space access over time in meeting that significantly larger market’s needs could in fact lead to your speculative vision becoming more likely than the realities it would face in today’s launch industry.
Moonies, Marsies, where do you want to go?
I can’t speak for Ed, but I want to go wherever I want to go, and affordably. I do not see how NASA’s plans put us on a path to get me there.
Absolutely, and to a lesser degree that’s also true for ISS and COTS, which is why I’m so annoyed COTS-D isn’t being properly funded.
“I can’t speak for Ed, but I want to go wherever I want to go, and affordably. I do not see how NASA’s plans put us on a path to get me there.”
Same here, but I’m wondering what Ed thinks. Or you for that matter. How about OASIS? Can Shuttle-C be part of an acceptable compromise? What else would have to be there? Or are you of the no-prisoners persuasion?
The SSME is of course also already man-rated. This gives DIRECT an edge over Delta-IV, which would no longer get its RS-68 man-rated for free. Conversely, they still propose man-rating the Delta-IV, but this would also man-rate the RL-10 which they plan to use on their upper stage for free, thus hiding the costs.
Which makes them perfect for the Shuttle C and takes away one of the prime objections of the original Shuttle C study from 1989 (which was a smokescreen for JSC wanting the fly the shuttles more often at the time).
I don’t understand, are you in favour of crewed Shuttle-C flights?
I’m hoping none of you are expecting the hopey, changiness of Obama to proliferate into NASA in any way. Everything so far has been more of the same with a nice grandiose rhetorical twist. I suspect a grand *shrug* and a ‘Yes We Can’ chant to follow.
Me: But they would seem to be the most cost efficient pieces of the whole lift.
Rand: Only for very low flight rates.
Truly?
I’m not in the field, but that just boggles me. The pieces I can see from the (yes, overly simplistic) general public side seem to (or, -should-) fall into one of these categories: actual fuel, steel housing, reusable electronics/actuators/hydraulics/gyroscopes, and disposable bits of basically negligible cost.
That sort of implies that the major costs are in 1) making/certifying/recertifying the housing, 2) fuel casting, 3) testing. Ok, transportation is probably pretty pricey too. But that should be fixable itself (absent Congress.)
A high flight level wouldn’t bring those numbers crashing downwards? I can understand a long re-certification -time- for each segment, but if you have enough of them that shouldn’t be a hold up.
That is, it might not be easy to push an individual segment up to four flights a year if you’re doing a lot of time-consuming testing. But if you’re manufacturing new segments by the dozens and reconditioning used ones similarly, you’d have a strong incentive for buying a whole lot more testing gear and automating all the most time consuming bits.
Cutting the ESMD slice of the NASA budget in half could be the best thing to happen to manned spaceflight in a very long time.
Moonies, Marsies, where do you want to go?
All of the above.
Or none of the above, depending on the ticket price.
Right now, no one can afford to go anywhere in space, except for a few multimillionaires and the astronauts done in Houston. Even they can’t afford to go very often. (NASA flies fewer astronauts now than they did in the 1980’s.)
Arguing over destinations instead of solving the transportation problem misses the point. Listening to the Moon vs. Mars argument is like listening to two guys who can’t afford a cab ride to the airport arguing over whether they should build their vacation resort in Hawaii or Tahiti.
At the same time, they insist that no one can develop an affordable taxicab
because “there is no market for taxis.” Their resort plans “can’t wait” for taxicabs to be developed, so they tell us taxicab development must wait several decades until they have finished building their resorts and “create the market for taxicabs.” When someone points out the long line of people who’ve signed up for Virgin Cab’s cross-town taxi, they simply close their eyes and say that trips to Hawaii or Tahiti are the only real market.
This is called “madness.”
Can Shuttle-C be part of an acceptable compromise?
It’s not a compromise when one side insists on getting everything they want and offers nothing in return.
A compromise would be an architecture that allowed NASA to begin trips to the Moon and Mars with existing commercial rockets while the rest of us worked on reducing the cost of space transportation, but the Moonie and the Marsie Churches won’t even consider something that reasonable. It’s the Great Big Rocket or Bust, as far as the Rev. Dennis Wingo and Father Bob Zubrin are concerned. So, once again, they will go bust.
I don’t understand, are you in favour of crewed Shuttle-C flights?
Not really, though it is one option. I would rather it be on EELV or Falcon 9 for humans. I seriously don’t understand what the big whinefest is all about with the health monitoring. A simple high power Wi-Fi between the EELV flight computer and the Orion and you are done with it. Use about 10 watts EIRP and you blast through anything on the way uphill.
The Aquilla that Buzz Aldrin came up with a few years ago did have the Orion on top of the Shuttle C. Would solve a lot of issues.
There’s some legitimacy to the “man rated” argument for launcher components. In order to meet “man rated” specs, components need to be designed to certain safety factors. Just before ESAS, NASA unveiled a new man-rating spec with safety factors that would rule out any Atlas except the 401 & 402. (It also ruled out the Shuttle.) When it became clear that even Ares I couldn’t meet the lofty goals of the man-rating spec, the requirements were gradually scaled back.
It’s hard to imagine that Gordo riding on a balloon-tank Atlas in 1963 had very high safety factors to rely on. I’m not advocating that we go back to the quite dangerous days of “The Right Stuff,” but it’s important to come up with realistic safety specs and consider the overall LOC/LOM numbers when writing a man-rating specification.
“Not really, though it is one option. I would rather it be on EELV or Falcon 9 for humans. I seriously don’t understand what the big whinefest is all about with the health monitoring. A simple high power Wi-Fi between the EELV flight computer and the Orion and you are done with it. Use about 10 watts EIRP and you blast through anything on the way uphill.”
I agree, but you don’t even need to do that. What we proposed for COTS 1.5 was using a regular TM receiver on the human spaceflight capsule to receive normal TM data streams. The crew (and software) monitor sensor data streams and draw conclusions about abort/no-abort. Experience has shown that for non-solid vehicles, there is generally several seconds available to make the call (see for example SeaLaunch failure). You can even let the ground continue to make termination calls so long as you build a few seconds delay into the execution, and have an FTS receiver on the capsule that triggers the abort.
There’s some legitimacy to the “man rated” argument for launcher components. In order to meet “man rated” specs, components need to be designed to certain safety factors. Just before ESAS, NASA unveiled a new man-rating spec with safety factors that would rule out any Atlas except the 401 & 402. (It also ruled out the Shuttle.) When it became clear that even Ares I couldn’t meet the lofty goals of the man-rating spec, the requirements were gradually scaled back.
Here’s one for ya. Which human rated specs are we talking about? There are the original JSC specs for the Shuttle 1700.7B I think, and then there are the MSFC and GSFC interpretations. If you use the analysis technique that MSFC uses the human rated factor of safety is 1.25. If you use the GSFC technique it is 1.5. Both of these are traceable back to the JSC spec.
We were in a tiff between MSFC and GSFC during our safety reviews for the tether mission on the Shuttle for our small sat (SEDSAT and the SEDS tether), and this became a big issue as the SEDS was a MSFC payload and the SEDSAT was flying on a GSFC Hitchhiker cross bay carrier. I don’t know if these differing methods of measuring the same thing has ever been resolved between the centers.
When it became clear that even Ares I couldn’t meet the lofty goals of the man-rating spec, the requirements were gradually scaled back.
Which is why the phrase should be purged from the language. It means whatever NASA needs it to mean for any purpose at hand at the time that it’s used.
“All of the above.
Or none of the above, depending on the ticket price. ”
OK, I think we’re all agreed on this. The thing is, I don’t think Congress will fund this and I don’t think they will believe it’s possible. The transport infrastructure is what we here care about, because once you have that, the rest will take care of itself. But Congress needs flags and bootprints missions too.
Whatever is done should create a reusable transport infrastructure that allows others (including international and commercial players) to follow more easily. It should also lead to the moon and eventually Mars and do so with frequent intermediate successes as part of a plan that is understandable by both decision makers and the public. In other words not something like “OK, the next five years we’ll build an in-space reactor, the five years after that a cryogenic depot, then aerobraking and boom: we’ve got the moon”. The good thing is infrastructure and flags and bootprints can be completely synergistic.
And even from the transport network side of things it does actually matter where we go first, if you believe ISRU is the key as I do. I say we should go L1->NEO->Moon->Mars. The moon is the first major target, as it should be because of ISRU, unless NEO missions determine NEO’s are a more accessible initial ISRU source. L1 is the cheapest and least risky place we can build a new transport node. It’s easier than the moon and helps reach it and therefore should come first. NEO missions can help determine whether NEO ISRU is more suitable as an initial goal and are an interesting target for a lander precursor.
For some perspective on incremental plans, see the Paine report linked to above, and google “Next Steps In Exploring Deep Space” by Wesley Huntress et al, hyperlinks coming up. I’m sure Dennis Wingo will have some interesting things to add to that.
“It’s not a compromise when one side insists on getting everything they want and offers nothing in return. ”
Absolutely. So what would be a good compromise? Your suggestion gives NASA the moon, but not the shuttle stack.
“It’s the Great Big Rocket or Bust, as far as the Rev. Dennis Wingo and Father Bob Zubrin are concerned. So, once again, they will go bust.”
I think you misrepresent Dennis Wingo, but I’ll let him speak for himself, since he is here with us. And you should give Bob Zubrin credit for the fact he focuses on existing or near-term technology and destinations that will excite the public. Those are good lessons to incorporate in an incremental plan that leads to a mature cis-lunar infrastructure.
Paine report
http://history.nasa.gov/painerep/begin.html
Next Steps In Exploring Deep Space
http://iaaweb.org/iaa/Studies/nextsteps.pdf
BTW, hasn’t ULA tested a regen nozzle RS-68? I notice Chair Force seems to refer to that as a “major modification” for the RS 68. But my impression is that it’s already been done as a prototype. Even if regen capability is a major modification, it at least is partial done.
And where’s the support for the assertion that the SSME is almost as cheap in marginal cost as the regen RS 68? I gather the SSME is still more complicated, isn’t being manufactured right now, and maybe a bit harder to turn into an air startable engine than the RS 68 (assuming that capability is desired at some point).
“And where’s the support for the assertion that the SSME is almost as cheap in marginal cost as the regen RS 68”
The DIRECT people are adamant this is the case. It will be interesting to see if they can back this up in their upcoming 3.0 release next week. They say they have numbers from PWR.
@ Karl
And where’s the support for the assertion that the SSME is almost as cheap in marginal cost as the regen RS 68? I gather the SSME is still more complicated, isn’t being manufactured right now, and maybe a bit harder to turn into an air startable engine than the RS 68 (assuming that capability is desired at some point).
I believe the actual cost numbers start entering the realm of proprietary data and the Augustine Commission may need to do some independent fact finding with confidential safeguards, if that is feasible under its mandate. But yes, my reading of the threads confirms Martijn’s suggestion that Team Direct has gone straight to P&W for their numbers.
As for a new air-start engine – why bother? It will be difficult and expensive to do what route is chosen.
Therefore use SSME for the core stage – experience with Shuttle proves the SSME works – and that allows RL-10s for the upper stage which are also flight proven. Therefore any “trade” between SSME versus RS-68 regen MUST also include the cost of J2X development.
Karl, can you imagine any scenario in which RS-68 regen is cheaper than SSME if we amortize the cost of J2X development onto every RS-68 regen deployed?
As for time, Ross Tierney asserts that P&W either has or very soon will re-start the SSME line and they assure him everything needed to re-open the line is ready to go.
Related, once Orbiter stands down, SSMEs can be salvaged and used for early Jupiter test flights even before a production line is up and running. Using existing 4 segment RSRM and existing SSME taken from the terminated Orbiter program leaves ET modifications and avionics and pad/crawler modifications as the only major hurdles needed before the first J-130 can test fly.