SLS Passes PDR

It’s hard to believe that this was said with a straight face:

“The review had to be incredibly detailed, so our plans for vehicle integration, flight software, test, verification and operations will result in a safe, affordable and sustainable vehicle design,” said Todd May, manager of the SLS Program at NASA’s Marshall Space Flight Center in Huntsville, Ala.

Emphasis mine.

Really? Affordable? And if it’s not affordable it’s not sustainable.

As for safety, here’s what I wrote in the book:

It should be noted that NASA currently plans only two flights for the SLS—one in 2017 to demonstrate the 70-ton capability, and one with a crew in 2021, to…somewhere. They have said that, when operational, it may only fly every couple of years. What are the implications of that, in terms of both cost and safety?

Cost wise, it means that each flight will cost several billion dollars, at least for those first two flights. If, once in operation, it has a two- or three-billion-dollar annual budget (a reasonable guess based on Shuttle history), and it only flies every couple of years, that means that each subsequent flight will cost anywhere from four to six billion dollars.

From a safety standpoint, it means that its operating tempo will be far too slow, and its flights far too infrequent, to safely and reliably operate the system. The launch crews will be sitting around for months with little to do, and by the time the next launch occurs they’ll have forgotten how to do it, if they haven’t left from sheer boredom to seek another job.

As a last-ditch effort to try to preserve the Shuttle in 2010, some suggested that it be maintained until we had a replacement, but to fly it only once per year to save money. The worst part of such a proposal would have been the degree to which the system would have been even less safe, given that it was designed for a launch rate of at least four flights per year. It was unsafe to fly it too often (as NASA learned in the 80s as it ramped up the flight rate before Challenger), and it would be equally so to fly it too rarely.

NASA’s nominal plans for SLS compound this folly, which is magnified by the fact that both internal NASA studies and independent industry ones have demonstrated that there is no need for such a vehicle to explore beyond earth orbit (existing launchers could do that job just fine, with orbital mating and operations), and it is eating up all the funding for systems, such as landers and orbital propellant storage facilities, that are necessary. All of this is just more indication that actually accomplishing things in space is the lowest priority for Congress (and unfortunately, the space agency itself, otherwise, the administrator would be more honest with the appropriators on the Hill).

But this PDR will be hailed by supporters nonetheless.

22 thoughts on “SLS Passes PDR”

  1. Space enthusiasts and science fiction writers have long posited that we’ll put families into cryo-sleep for long duration missions, and NASA has always been interested in developments on that front. Little did anyone suspect that the main use of such technology in space flight would be to put NASA employees into suspended animation so they wouldn’t leave or have their launch skills get rusty during the years, perhaps decades, between manned launches to low Earth orbit.

    1. George,

      That isn’t a bad idea actually. Most of the standing-army costs for SLS are probably payroll related directly or indirectly. So just cold-sleep the SLS standing army 3/4 of the time…might actually make it somewhat affordable if you only paid them for the time they weren’t in hibernation…

      ~Jon

  2. If the SLS keeps thousands of engineers, contractors and other personnel employed then it will be considered a political success. It is a jobs program after all. You’re judging it by other criteria, such as will it be an affordable, safe and practical launch platform. That’s why the politicians are running things. Their success criteria is winning elections by spending money on their constituents and cronies, not actually doing stuff in space. To them, if it never leaves the ground but helps them win reelection, SLS will have served their purposes. Until enough taxpayers and voters change that political calculus, we’ll forever have political boondoggles like the Bridge (or Rocket) to Nowhere.

    1. The better political argument might be, “Look at the flight rate. The thing is going to blow up. Then where’s your career going to be when the heads start rolling?”

  3. You must understand that they talk in code. Remember “safe, simple, soon”? One must read between the lines and translate such things to “monstrously unsafe, extraordinarily complex, and delayed indefinitely or cancelled”. Similarly, “safe, affordable, and sustainable” translates into, well, you know.

    What I find interesting is how the political machinations of the Johnson presidency in order to get Apollo rolling have reverberated down the decades in the form of a permanent federal subsidy to specific congressional districts being sliced out of the NASA manned spaceflight budget. In many ways Apollo set us back a bit in our sustainable capability to perform manned spaceflight, and the political deal that enabled Apollo has held us back even more. Seemingly it’s been holding us back an increasing amount over time. Shuttle was a significant hindrance to manned spaceflight but at least it was something. SLS is an order of magnitude worse. We’d be better off even if we merely spent the next 3 decades building space stations in LEO.

    1. I sometimes wonder what might’ve happened had Kennedy set the deadline for a lunar landing for the end of the 1970s instead of the 60s. Would NASA have taken more time to develop a sustainable program without having developed the “waste anything but time” institutional culture? Would the whole thing have been canceled (probable)?

      1. If you really want to make yourself sad, imagine what would have happened if NASA had been designed to set aside about $1 billion/yr for fundamental rocket research and an equivalent amount every year to accumulate as prize money for various milestones (such as landing men on the moon, reusable spacecraft, etc.) We would be incomparably farther along in manned spaceflight having spent vastly less money.

      2. I wonder if Kennedy would have said, “The U.S. wants to start sending people to the moon, what is the per seat cost for a commercial service?”

      3. Larry: I think there’s a good chance it would have eventually been cancelled.

        I’ve come to the conclusion that a government-run space program in a democratic society is almost guaranteed to fail. Each party has its own policy preferences and its own constituencies to please, not to mention its own cronies to enrich.

        When the government changes hands, the incoming party has a tendency to repudiate the policies of its predecessor, and strike off in a different direction.

        Apollo succeeded because it was considered to be an important battle in the Cold War, and also because it had a short time frame. The same party controlled Congress throughout that period, and controlled the Presidency until January 20, 1969. By the time Nixon took office, the Apollo program had a good head of steam and was hurtling towards its goal. About the only thing Nixon could have done to affect it at that point would have been to ask Congress to cancel it in his State of the Union address. Needless to say, that would have been unpopular in 1969.

        So I think the spinning-our-wheels-but-not-getting-anywhere phenomenon we have seen for the last 40 years is the norm. Apollo was a rare and lucky exception.

        An authoritarian society is better able to keep a single-minded focus on a long-term objective. But of course, it lacks the dynamism of a free society. America was still free enough and innovative enough in the 1960s that we were able to beat the Soviet authoritarians.

        I’m not arguing for an authoritarian government; rather, I’m arguing against a government-run space program in a democratic society.

  4. Sustainable?

    Ummmm… engines, anyone? Space Shuttle main engines, to be exact. (Also called the RS-25.) That’s what SLS block 1 is supposed to use for its core engines – four SSME’s.

    They plan to use *existing* SSME’s from the shuttle program – engines that have mostly already flown and been put in storage. But with SLS, they will be used on an expendable booster – and we’re no longer making the SSME, and haven’t made any in about a decade.

    I’m not positive, but I think only 14 SSME engines exist, so that’s enough for three SLS flights, including a fist-stage-only test flight.

    My guess; that’s the biggest reason why they plan just one full up test launch, followed by a manned mission to… somewhere; because after that manned launch, they won’t have enough engines for another.

    They say they are going to develop a “low cost, non reusable version of SSME” but as far as I can see, they haven’t even started yet. What that’d be is basically a whole new engine, and there’s no other option: we lost SSME production capability a decade ago.

    I don’t see how they can possibly call SLS “sustainable” when the engine it’ll need to go past launch 2 hasn’t even been designed yet.

    But then again, I don’t see how they can possibly describe the thing as “affordable” either.

    1. We built over 40 RS-25’s for the Shuttle program, and some of them only few once, as I recall. However, the earlier Block I engines were long ago stripped apart for inspections and testing, as were some of the Block II’s. I think we ended the program with 15 that were still flyable.

      1. 15… Hrmmm. Then I’ll bet they use three rather than four for the first-stage-only test, thus leaving enough engines for three more launches.

        After that… they’re relying on a very different engine that has the minor drawback of not even existing on paper yet. And I’m not expert, but I feel somewhat safe in saying that a rocket probably won’t fly very well until its engines actually exist. 🙂

        1. It is the 21st century version of the fable where the emperor has no clothes. Britain has aircraft carriers without aircraft, so why can’t the US have a heavy lift space launcher without engines?

  5. I wonder how many more preliminary design reviews this vehicle will go through before one of them sticks or the program is canceled.

  6. So have they figured out the tank sizes or which engines they will be using in this PDR or not?

  7. If it’s a standing army that is required, then why not create the army?
    As one would join the military or the peace corps, he/she could join the SLS corps. After their stint they could even be part a reserve SLS corps. What you get is a large body of skilled SLS people preserving all the knowledge, procedures, and operational readiness.

    A religious order would do the same trick, with all the priests, monks, bells and tithes.

    1. You know, some of the PDR’s in your link really struck me as Kafkaesque fiction. I mean, even distilling things down for a brief overview, the bullet points were things llike:

      * Began identifying commercially available primers for cryogenic application that would be compatible with new federal regulations.

      * Conducted a series of technical interchange meetings with Jet Propulsion Lab [gotta spell that out?] to discuss cooperation on outer solar system exploration.

      * Met with officials at Goddard Space Flight Center to discuss possible collaboration on the launch of potential space science missions.

      I’m not sure how to express what I feel, except to suggest that almost any word in any of the above bullet points could be put in bold or italics and the joke would still sound fresh.

      Take the last one. They “met” with officials that work for the same agency they do! They met to “discuss” collaboration – within the same agency. Well, not really collaboration. That would be going to far. Wouldn’t want to be so bold as to come right out and propose collaboration right off the bat. That would be far too forward.

      They discussed possible collaboration – on a launch. The SLS is the only NASA launcher in town, or potential NASA launcher, so it might come up in a discussion with other NASA folks who might – or might not – have something to launch into space. It probably made for an awkward moment when someone accidentally broached the topic. But playing coy, Goddard SFC only said it might be a launch of a potential science mission. Wouldn’t want to over commit themselves on the first meeting, oh heavens no.

      There are pages and pages of outright hilarity like that.

      1. The gritty reality is that these other branches are probably real tired of being asked to generate power point rationalizations for a big rocket. There’s a fair number of unmanned missions that could become viable with the capabilities of a Saturn V class rocket (anything involving lots of mass, high delta-v, and/or a large fairing size). But where’s the money for these pipe dreams coming from?

        This sort of language is IMHO a strong indication that a lot of groups in NASA are distancing themselves from the SLS.

      2. Well, I could easily rewrite the first bullet point above:

        * Began identifying commercially available primers for cryogenic application that would be compatible with new federal regulations.

        As

        * Spent the last two days surfing the web, hitting commercial websites about primers and trying to find one that meets whatever new spec the idiots have come up with. Somehow I have to milk this task till 2016.

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