SLS Begins Critical Design Review

Space Launch System in flight. (Credit: NASA)
Space Launch System in flight. (Credit: NASA)

HUNTSVILLE, Ala. (NASA PR) — NASA’s Space Launch System (SLS) Program kicked off its critical design review May 11 at NASA’s Marshall Space Flight Center in Huntsville, Alabama.

This new rocket will be the most powerful launch vehicle ever built. It is designed to be sustainable and evolve to carry crew and cargo on deep space missions, including an asteroid and ultimately to Mars.

Milestone reviews like the critical design review are just that — critical. The critical design review demonstrates that the SLS design meets all system requirements with acceptable risk, and accomplishes that within cost and schedule constraints. It also proves that the rocket should continue with full-scale production, assembly, integration, and testing and that the program is ready to begin the next major review covering design certification.

“We’ve never said building a rocket is easy,” said SLS Program Manager Todd May. “We pore over every part of this rocket during these reviews. Thousands of documents and months of time are put into making sure the design is sound, safe and sustainable, and will make NASA’s mission of furthering human spaceflight possible. We are making advances every day on this vehicle.”

Each element for the rocket — including boosters, engines, stages and Spacecraft and Payload Integration & Evolution (SPIE) — undergo their own reviews before this week’s kickoff of the integrated program review. Boosters, stages and engines have passed their critical design reviews, and the SPIE Office is in the process of completing its critical design review. SPIE is responsible for the design and development of several parts of the top of the rocket, including:

  • Orion stage adapter – connects the Orion spacecraft to the SLS
  • Interim cryogenic propulsion stage — gives the Orion spacecraft the big push needed to fly beyond the moon before the spacecraft returns to Earth during the first flight test of SLS
  • Launch vehicle stage adapter — used to connect the core stage and interim cryogenic propulsion stages

SPIE also works to prepare for the future evolution of SLS to provide the capabilities needed for human missions to Mars. The office oversees in-house research and partners with academia, industry and other government agencies to develop new technologies and systems that will benefit not only SLS, but also the larger U.S. launch industry.

The SLS Program critical design review is targeted to conclude in late July.

The first flight test of the SLS will be configured for a 70-metric-ton (77-ton) lift capacity and carry an uncrewed Orion spacecraft beyond low-Earth orbit to test the performance of the integrated system. As the SLS evolves, it will be the most powerful rocket ever built and provide an unprecedented lift capability of 130 metric tons (143 tons) to enable missions even farther into our solar system.

For more information on SLS, visit:

  • I look forward to the congressionally mandated first flight of the SLS and Orion on December 31, 2016. Perhaps NASA ought not to be funding and designing capsules and launch vehicles anymore. Once can’t possibly repeat this meme often enough.

  • Paul_Scutts

    “sustainable” is definitely not a word that should be used to describe the SLS. How sustainable? Not on cost, either development or per launch. Not on the projected (in)frequency of use. Not on the lack of definite plans for use, just a vague reference to the Moon and beyond (asteroids and Mars). The term definitely fits SpaceX’s Falcon Heavy, but, not NASA’s Senate Launch System. No way Jose.

  • windbourne

    If we are going to the moon and mars, then we NEED multiple SHLV.
    IOW, assuming that only spaceX creates a SHLV, then we NEED the SLS.
    Where life gets interesting is if another group, esp. BO, announces their own SHLV to be ready by say 2022.
    At that point, the cost of launch for the SLS becomes prohibitive.

  • Bob Redman

    The SLS is going to be the central workhorse of manned missions beyond LEO.
    SpaceX will also be central to our efforts to expand into the solar system.

    The cynicism I see about the SLS being a ‘rocket to nowhere’ is absurd. If NASA announced tomorrow that they were going to use the SLS to land people on Mars within 10 years, with no additional funding from Congress in sight, that would be absurd.

    Congress, like it or not, is giving them just enough money to build the SLS and to run the ISS for the time being. Under these constraints, NASA is using this money wisely to build the core foundation rocket that will to take crews and related hardware wherever future Presidents and Congresses decide to go.

    My guess is that more funds will be freed up when the ISS is finally decommissioned. The added funds will allow habitation modules and propulsion systems to be created for crews to travel even deeper into space. Meanwhile, the rocket to get them there, will be designed, built and ready.

    Along those same lines, I’m absolutely rooting for SpaceX and Falcon Heavy to succeed! Elon Musk has said that his ultimate goal is to go to Mars. I have no doubt he will, perhaps even before SLS. Even so, Musk has never said that he will land people on Mars in 10 years. Without the habitats and propulsion systems in hand, he knows that would be absurd as well.

    What surprises me, is that so many people are willing to give SpaceX the benefit of the doubt, and, at the same time, insist that NASA is on a fool’s errand. Working with the money it has been given by Congress, NASA is looking to the future and also giving SpaceX technical and engineering expertise, which Musk has publicly and repeatedly said has been a huge help to them.

    We need NASA’s SLS and SpaceX’s FH to succeed together if we seriously want to journey outward.

  • Michael Vaicaitis

    I’m sorry to say, but your comments reek somewhat of naivety. You seem to be under the misapprehension that SLS is a NASA designed rocket; it is not. It is a congress mandated design to utilise ex-shuttle technology so as to keep the gravy train flowing to certain industrial lobbyists. Designing a SHLV using a LH2 first stage together with solid boosters is the expensive route to take – NASA would not have done this if they didn’t have to.

    “Without the habitats and propulsion systems in hand, he knows that would be absurd as well.”
    Also, FH is simply SpaceX’s HLV based on the F9 architecture. BFR (Big F***ing Rocket or Big Falcon Rocket, or ???) is expected to be their methalox Raptor powered SHLV for the 2020’s and the lift vehicle for the MCT (Mars Colonial Transport). It is generally thought that BFR will be fully reusable with a 150+ tonne lift capability. Hopefully Musk will reveal more details of BFR and MCT later this year. Regardless of the details, BFR will no doubt be cheaper to develop than SLS, cheaper to build than SLS, cheaper to launch than SLS (even as expendable) and almost certainly more capable than SLS.

    The complaint against SLS is that it is either: overpriced for what it will be able to do and/or it is a missed opportunity to build something either more affordable, and thereby more useful, or something more capable, and thereby more useful. Of course, the same sort of criticism could be levelled at Orion, which value for money wise, is even worse than SLS.

    If you want to “travel even deeper into space” then you need to build an exploration stack in orbit: propulsion, habs, landers, etc.. No SHLV is going to be big enough to launch an entire Martian transport architecture directly from the surface of the Earth.
    “Meanwhile, the rocket to get them there, will be designed, built and ready.”

    No it won’t; the rocket, whether SLS or BFR will not “get them there”. Furthermore, SLS will be so difficult and expensive to manufacture and launch that it will limit any funds left over for actual mission hardware.

    I applaud your support your support of NASA, but supporting SLS and supporting NASA is not the same thing at all.

  • Who is we, you? Both SLS and Orion are already WELL beyond borked. It’s been a decade and twenty billion dollars, how much of this crap can you take? I hope you are tolerant of endless fiasco in America.

  • SLS and Orion are already the central workhorse of endless folly at NASA.

    That is never going to change. It will be your problem for a long time to come.

  • Steve Ksiazek

    I don’t understand why any private company would build a SHLV, knowing that NASA already had the SLS to perform these missions. The fact is that there aren’t enough missions to support 1 family of SHLV. Having multiples is just crazy. I hope everyone realizes that the SpaceX SHLV isn’t launching without funding from NASA.

  • windbourne

    Because the SLS will cost 1-2B PER LAUNCH for 70 tonnes.
    OTOH, MCT is supposed to cost around 300M to launch 150-200 tonnes.
    If BO can do something similar, then SLS is dead.

    And if you think that SpaceX is NOT launching regardless of NASA, then you have not been paying attention. In particular, they are investing money into Solar City, and shortly into an internet network. All of this is designed to fund it.

  • Steve Ksiazek

    Let’s do some more math. Assume that they finally get the MCT turned from an e-paper rocket into a real launch vehicle. It’s not going to cost SpaceX SLS-type money for that, but I remember Musk asking for 2 BILLION dollars at one time. Then they need multiple flights, just for NASA certification. I see an investment of at least 4 BILLION required by SpaceX. Sure, Musk wants the monopoly on NASA and DOD launches to fund this effort, but that is just a huge waste of cash to replace a launch system that NASA already has.
    I don’t think it actually costs that much to build each SLS launcher. Those numbers come from the overhead that each NASA center adds to each mission. The actual costs of assembly are much-much less. And those overhead costs for each NASA center aren’t going away anytime soon.

  • windbourne

    Musk said that he would only need 2 billion to build the engine and the rocket. That was a max. He is right now building and testing parts and will later this year start testing of the full engine.
    He has a factory for building production AND r&d rockets. Basically, he is now building this rocket on his own dime.

    Certification, as I understand it is, is less about the rocket, and more about the company process. If that is so, then it will mean that he will simply have relatively little paper but a few launches.
    And as long as the first launch is successful I have no doubt that commercial space will pick it up.
    In particular, I suspect that Bigelow will want to use him since it will be 150-200 tonnes for 300 million. For that, if he really has the volume, he can send up several ba2100s at a time.

    Now as to SLS costs. The shuttle cost 750m for equipment. That was nearly 10 Years ago, with fewer players involved. Why would you think that SLS will cost any less than 1B for equipment alone, not including all the overhead that old space charges NASA and that assumes some 4-6 flights / year.
    Considering that SLS is prohibited from flying commercial flights and the GOP continues to gut NASA, how do u expect them to hit 1 flight / year, let alone 4-6?

  • Rob

    I don’t think there’s much chance of BO having a heavy lift rocket any time soon, much less a super heavy lift.

  • Rob

    “Musk wants the monopoly on NASA and DOD launches to fund this effort”

    I strongly disagree. SpaceX has shown that they’d rather price their launches to be competitive with a high profit margin rather than completely undercut the market and form a monopoly. And that strategy probably results in them making quite a lot more money, as well.

  • windbourne

    Oh, I am not thinking of soon. It really will take a while for that. It really has taken SpaceX 15 years of building up their infrastructure to really be able to build a SHLV. And that was with help from NASA (the 299M helped, but realistically, it is the engineering and QA help that really pushed them).

    BO has had help, but not to the same level, which is too bad. I would like to see us help get them off the ground. We need more companies that compete.

  • windbourne

    In fact, I suspect that Musk will be fine with seeing other companies get started and moving. Musk knows that he wants to be a medium fish in a large ocean, rather than the large fish in a pond, the way that ULA has been.