New SLS Worry: Leaks
by Douglas Messier
Managing Editor
The latest Government Accountability Office (GAO) review of NASA’s massive Space Launch System (SLS) has a depressingly familiar ring to it. Tell me if you’ve heard this before:
- schedule continues to slip
- costs continue to rise
- core stage could develop fuel leaks.
Yeah, that does sound famil– Wait…WHAT?!?
NASA officials are concerned that leaks could develop when the the massive stage is filled with super cold fuel during the green run, which will be a full-up test firing of the stage and its four RS-25 engines that will be conducted later this year at the Stennis Space Center in Mississippi.
“According to these officials, they have conducted extensive scaled testing of the gaskets and seals used in the core stage; however, it is difficult to precisely predict how this large volume of liquid hydrogen will affect the stage,” the GOA reported.
“Should leaks or other issues be discovered, the program will need time to assess and mitigate difficulties or glitches, which could delay shipping the core stage to Kennedy Space Center and the enterprise integration and test schedule,” the report added.
The revelation came in a new GAO review that examined NASA’s progress on its major projects. The report was completed before the coronavirus pandemic caused a slow down in work across the agency.
SLS is a key element in NASA’s Artemis program, which is designed to allow astronauts to return to the moon. SLS will launch the Orion crew spacecraft as well as elements of the lunar Gateway, a human-tended station that will orbit the moon.
The GAO that SLS costs are continuing to rise as the schedule slips further into the future.
“The program reported further development cost growth of $700 million since 2019, for a total increase of approximately $1.7 billion—or 24.6 percent—above the program’s development baseline,” the report stated. “This cost growth is tied to a delayed launch date of March 2021, but this date and the associated cost growth remains tentative until NASA officially establishes a new launch date.”
NASA has already slipped the first launch of SLS to November 2021. The delay is, in part, due to a work slowdown caused by the coronavirus pandemic.
The GAO report was released the same week that NASA awarded study contracts to Blue Origin, Dynetics and SpaceX for a Human Landing System to place astronauts on the lunar surface in 2024. None of the proposals relies upon SLS as a launch vehicle.
GAO’s assessment of SLS follows.
NASA: Assessments of Major Projects
Report to Congressional Committees
Government Accountability Office
April 2020
Space Launch System
The Space Launch System (SLS) is intended to be NASA’s first human-rated heavy-lift vehicle since the Saturn V was developed for the Apollo program. SLS is planned to launch NASA’s Orion spacecraft and other systems on missions between the Earth and Moon and to enable deep-space missions, including Mars.
NASA is designing SLS to provide an initial lift capability of 95 metric tons to low-Earth orbit, and be evolvable to 130 metric tons, enabling deep space missions. The 95-metric ton capability will include a core stage, powered by four RS-25 engines, and two five-segment boosters. The 130-metric ton capability will use a new upper stage and evolved boosters.
Project Summary
After a series of delays, NASA had planned to conduct the uncrewed demonstration of Artemis I in June 2020, but the agency is currently reevaluating this date. The program reported further development cost growth of $700 million since 2019, for a total increase of approximately $1.7 billion—or 24.6 percent—above the program’s development baseline. This cost growth is tied to a delayed launch date of March 2021, but this date and the associated cost growth remains tentative until NASA officially establishes a new launch date.
Although the SLS program has made progress in delivering the core stage for testing, the SLS program projects it cannot support an Artemis I launch until at least April 2021. The core stage is currently at Stennis Space Center for green run testing where it will be test fired in flight-like conditions.
However, the program needs to complete some production work and software verification before it can test fire the engines. Other SLS elements, including the Interim Cryogenic Propulsion Stage (ICPS) upper stage, Solid Rocket Boosters, the Launch Vehicle Stage Adaptor, and the Orion Stage Adaptor are complete or nearing completion.
Cost and Schedule Status
After a series of delays, NASA had planned to conduct the uncrewed demonstration of Artemis I in June 2020, but the agency is currently reevaluating this date. Program officials attributed the delays to production challenges with the core stage—which functions as the SLS’s fuel tank and structural backbone.
According to program officials, Boeing underestimated both the complexity of engine section assembly and the time and manpower that it would need to complete the effort. As a result, the core stage was not fully assembled and shipped from the Michoud Assembly Facility to Stennis Space Center for testing until January 2020. As of January 2020, the SLS program estimated that it could be ready to support an Artemis I launch date no sooner than April 2021.
The SLS program reported an increase of Artemis I development costs of $700 million since 2019, for a total increase of approximately $1.7 billion—or 24.6 percent—above the program’s development baseline. This cost
growth is tied to a delayed launch date of March 2021, but this date and the associated cost growth remains tentative until NASA officially establishes a new launch date.
Further, when updating its cost estimate to reflect current planning, the program reallocated some costs for liquid engine development and booster efforts that had been included as part of the SLS Artemis I baseline cost estimate to future missions. These costs remain in the baseline cost estimate but are not included in the updated program cost estimate, which results in an underreporting of cost growth.
Integration and Test
In January 2020, NASA shipped the core stage to Stennis Space Center to start green run testing, where multiple events take place including firing the four main engines for about 500 seconds under flight-like conditions. This test will stress the flight components as well as the ground equipment. However, program officials told us that some production work, originally planned for completion at Michoud Assembly Facility, remains to be completed in parallel with test preparation at Stennis Space Center before test firing the engines.
Program officials indicated that one of the top remaining technical risks to the green run test is that the core stage may develop leaks when it is filled with fuel. According to these officials, they have conducted extensive scaled testing of the gaskets and seals used in the core stage; however, it is difficult to precisely predict how this large volume of liquid hydrogen will affect the stage. Should leaks or other issues be discovered, the program will need time to assess and mitigate difficulties or glitches, which could delay shipping the core stage to Kennedy Space Center and the enterprise integration and test schedule.
The green run test is also the first time NASA will test the SLS flight software on an integrated flight vehicle. The program is developing two versions of flight software—one to support green run testing and another to support the Artemis I mission. Program officials expect an updated version of the green run software—required to test fire the engines—to be released in April 2020. However, the program’s current schedule leaves little margin between the release of this version and the engine test fire, and should there be any software issues, this could delay green run testing.
Other Hardware
In addition to the core stage, the SLS program has made progress in developing the Interim Cryogenic Propulsion Stage (ICPS) upper stage; Solid Rocket Boosters; the Launch Vehicle Stage Adaptor which connects the Core Stage with the ICPS upper stage; and the Orion Stage Adaptor which connects the Orion spacecraft with the upper stage. The ICPS upper stage was delivered in October 2018 and the Orion Stage Adaptor is ready at Kennedy Space Center. Additionally, the program expects the Launch Vehicle Stage Adaptor to be delivered in April 2020 and the Solid Rocket Boosters to be delivered in July 2020.
21 responses to “New SLS Worry: Leaks”
Leave a Reply
You must be logged in to post a comment.
“The SLS program reported an increase of Artemis I development costs of $700 million since 2019, for a total increase of approximately $1.7 billion—or 24.6 percent—above the program’s development baseline. This cost”
Imagine what a competent engineering organization could do with that money, not to mention the billions before it? Stop the sunk cost fallacy arguments and cut your losses people!
Its not about building good rockets, its about creating jobs in Congressional Disctricts. So you don’t need good engineers designing ut, just bureaucrats who channel jobs to the right districts.
Building aluminum tanks is suppose to be a mature technology. LM built around 140 for the Space Shuttle Program. How could it leak?
this is Boeing, not LM.
Boeing has been working towards lowering cost by cutting QA and offshoring.
Sadly, this remains true to this day.
Maybe for their commercial airplanes. But SLS is cost-plus so Boeing would be taking money out of its own pockets if it tried to economize on that. In any case, Michoud isn’t offshore – and won’t be except maybe in the case of a hurricane worse than Katrina.
The tank isn’t leaking it’s the valves and gaskets connected to tank that might leak. STS had same issues.
So why are they worried about it? Just keep the tank topped off until the end. It seemed to work with the STS.
Actually it caused a lot of issues with STS. Scrubbed launches, etc. It is certainly a concern but nothing surprising. They are obligated to disclose any concerns that might affect schedule and cost regardless of how big an issue it is.
No wonder Elon Musk won’t touch Hydrogen…
Not sure that that it could develop leaks is a revelation. If it’s now considered likely or somewhat likely to develop leaks, then okay, that’s a revelation, but just that it’s possible…I dunno. I mean, this is what testing is for. This is the all up test, and that the all up test may reveal problems, and problems will cause delays – no duh. That’s not news.
The question is, just how worried are they. And why are they worried – do they have some info they’re not telling us? (Like that they knew their scaled component testing was an insufficient procedure but signed off on it anyway, etc.)
Anyway, don’t get me wrong – I’m no fan of the SLS boondoggle
Boeing still has not learned any lessons. They are still being ran like MBAs, not Engineers.
If Calhoun was doing his GD job, then SLS would have been stopped sometime ago and each part of this would have been tested BEFORE building a final one.
SpaceX shows how to do things and yet, old space is not learning from them. Considering that BO has had no major issues, I am guessing that they have also been going through testing each part. Now, just time for them to get a move on, get new shep into a commercial run and new glenn being shown.
I assume they are still on track for 2021 for their first launch. Meanwhile, down Texas way, SN4 looks like a dragon waking up with its snorting gas and all the methane flaring.
https://twitter.com/SpacePa…
Boy oh Boy, if I were Boeing/LM, I would be nervous about this.
Between SX and BO, AND their doing a better job on quality, I would be concerned for future contracts.
In the talk today in response to a question Administrator Bridenstine indicated NASA would be open to the possibility of a competitor to SLS/Orion deliverying astronauts to the landers in lunar orbit if it looked feasible. The full recording of the talk is here.
https://www.csis.org/events…
Bridenstine made those remarks in the context of some indefinite timeframe after the initial Artemis missions. He was very definite that the first three Artemis missions would be flown by Orion and launched by SLS. That allows him to make public obeisance to what Sen. Shelby wants right now while also opening up the possible option of making other arrangements, partially or entirely, at some fuzzily defined point following the first Artemis landing mission in 2024. In military terms, this is a flanking move.
I think he’s trying to gently prod Boeing into straightening up and flying right. That is certainly the first thing to try. The first time around, it was Pence who was the “bad cop” and Bridenstine the “good cop.” There was no obvious response, at that time, from Boeing. But that was over a year ago and Boeing hadn’t hit rock bottom yet. Now it has.
Perhaps the company still has enough functional neurons remaining in its corporate skull to appreciate that it’s time to join Cost-Plus Anonymous and start going to meetings. So J.B. can still be the good cop, but with the subtle hint that not even his patience is without end and that the possibility is still open that that “if our current contractors can’t perform, we’ll find some who can,” guy could come back and actually put that into effect.
Or J.B., could just bring down the hammer himself. I have no doubt that he is prepared to do that. But I can also appreciate that he wants to just drop hints for now rather than throw down a gauntlet.
Last year, it was judged, in a quickie study, that insufficient time was in-hand to adapt an ICPS or Centaur 5 upper stage to FH and put Orion up on that, even unmanned, as an alternative to SLS for Artemis 1. But that was when Artemis 1 was still supposed to fly in 2020. Since then, it has slipped all the way to nearly the end of 2021 and will almost certainly slip more, into 2022.
There now seems more than adequate time to put a ULA hydrolox upper stage on an FH to do Artemis 1 by 2022. Given that FH also doesn’t suffer from SLS’s production limitations, and will fly several more times in the interim, it could be human-rated by then too. And another such FH could be quickly built to conduct Artemis 2, with crew, in 2023. Then, a third such FH could launch Orion for Artemis 3 in 2024.
Even should human-rating FH stay off the table, Orions could still be launched empty to LEO for all three missions. For Artemis 2 and Artemis 3, Orions could be met there by Crew Dragon 2s, or perhaps even Starliners, from which the crews of four would transfer, then the Orions could go on their ways to doing, respectively, a lunar flyby and a meeting with a lander in NRHO. They would then execute direct returns to Earth. The D2’s used as LEO taxi’s could land empty.
Of course, all this also assumes Orion will be ready to go on the stated schedule. That seems to be still at least somewhat in doubt.
Thus far J.B. has refrained from being a public hard-ass anent SLS and Orion. But crunch time is rapidly approaching. J.B. has not been averse to buying at least one more Soyuz seat as a hedge against additional near-term problems with Crew Dragon 2. It’s all too soon going to be time for equal prudence anent the Artemis missions. That means starting real work on a real hedge against the non-readiness of SLS on the required schedule. If that is to be done, along the lines just outlined, the doing will probably need to commence in four months or less.
J.B. has been a good chess player to this point. Well before summer’s end, we may get a chance to see how well he plays Chicken too.
There are people who view all problems as potentially fixable via political influence and other backroom skulduggery. Michael Gass, the former CEO of ULA was one of those. He spent eight years paying SpaceX no attention whatsoever, then tried to invoke the usual political influence incantations in 2014. They didn’t work. He had no Plan B. Then he got canned.
Pretty much the entirety of Boeing seems to have degenerated to the same abysmal condition. Bankruptcy followed by liquidation followed by one or more new owners of erstwhile Boeing’s various pieces kicking serious ass and replacing old-timers wholesale is now, I think, pretty much the minimum it will take to make something once again useful of Boeing.
Space shuttle main tank also had problems with leaks. Hydrogen is a very small molecule. There is nothing revelatory or remarkable about this admission. All the lessons of STS are being applied here. People just looking for excuses now to fault SLS.
nah. We do not need to look for ‘excuses’.
The Shelby Lunatic System has a large set of issues and waste of taxpayer $.
That’s not all that hard and he has five other children. People have been managing it for, well, as long as there have been humans and our species is far too good at it.
Sizable chunks of our species seem to be losing the knack. That way lies extinction on the installment plan. In some cases, such as Russia, that will prove to be a feature rather than a bug. Many other places – not so much. I, for one, will certainly miss the Italians when they’re gone – and they are rapidly dwindling.
The biggest and only issue that cannot be solved with SLS, is price per launch. The bill is around 1.5 billions all included. This is not sustainable when the next challenger is falcon heavy with 60 tons in leo for maybe $200 millions. At least it is not sustainable in a depressed economy. NASA just doesn’t want to admit the concept of disposable rocketry is wrong in this economy.