Various Thoughts about the ESAS report

I stumbled across a witty poem today at Crooked Timber that more or less reflects my mood about the ESAS report:

If something can get worse it will
Is a phrase I’ve often sardonically used
But here’s some grist for Mr Murphy’s mill
I used to be disgusted
Now I’m just amused

I’ve been thinking about what to say and how to say it about this report for the past two days. I was putting it off hoping to come up with something very clever and insightful (and also waiting for more time to do such a writeup), but I’ve got some time on my hands now as I wait for my computer to spit out pretty FEA pictures telling me how screwed up my tank sump design is, so I may as well make the most of it.

Before I am too tempted to point out all the glaring fallacies that Mark’s been churning out over at Curmudgeon’s Corner, I want to start by commenting on an analysis that I mostly agree with. Henry Vanderbuilt over at the Space Access Society is one of my favorite space commentators. The fact that his views often are fairly similar to mine, and that he’s seen as being a rather smart person in the alt.space crowd thus making me look smart too has absolutely nothing to do with it. Anyhow, in previous Space Access Updates, Henry had been taking a cautiously optimistic tone toward the whole VSE. There was originally hope for it to actually be done in a non-stupid way, and there was even hope for it helping catalyze the development of a true and thriving cis-lunar economy. It was a long-shot, but sometimes long-shots are worth it. As part of this gamble, the SAS had joined a coalition supporting funding increases for NASA for carrying out the VSE. However, as NASA’s plan has been rolled out over the past several months, Henry has changed his mind. As he put it:

To be blunt, we have big problems with this plan. It’s the same basic approach as Apollo, disposable (mostly) spacecraft, on big NASA-proprietary boosters, flown a few times a year, by a standing army of NASA and contractor employees. This is Apollo 2.0, with somewhat more delivered exploration, at moderately higher cost, on a significantly slower schedule.

We have to ask, after forty years of stunning technological progress, shouldn’t we be able to improve on Apollo’s cost-to-exploration ratio a bit more than this? US taxpayers will get little more Buck Rogers for their inflation-adjusted buck than they did in the 1960’s

Henry then goes on to hit on many of the same points I’ve been hitting on over the past few months. One of his good points is the danger in putting too much faith in commercial ISS resupply contracts and the other “Innovative Programs” that Griffin has been touting in order to gain the support of the alt.space crowd (emphasis mine):

[T[here are potentially useful bits in ESAS, not least of them the plan’s flirtation with Station resupply being put out to commercial bid. Mind, with all due respect to various of our colleagues who pin large hopes on this, we have to say we see a strong liklihood that it, along with all sorts of other useful NASA non-manned-space functions (what does that first “A” stand for again?) will end up defunded to pay for ESAS’s big upfront vehicle developments.

We also see considerable danger that commercial Station resupply will turn into (despite the best will in the world by those at HQ conceiving it) a tarbaby (a glue-trap for you kids never taught the old folk tales) as the people actually administering Station set impossible standards for would-be vendors, until they go broke and go away. (Last we heard, not even Shuttle and Soyuz meet the official “prox ops” Station docking rules; both had to be grandfathered in.) Our hypothetical turf-jealous Station managers could then go to Congress saying “see, those damned
amateurs couldn’t hack it, now fund us pros to do the job!”

The only part of ESAS that is even worth funding is the Innovative Programs office, but precisely because it is seen as being “off the critical path”, it is the most vulnerable to cost overruns and budget cuts. As it is, it’s looking as though Congress is trying to zero-out Centennial Challenges and the ISS commercial contracts already. Without the Innovative Programs work, there really isn’t anything in the ESAS architecture worth supporting, as the rest of it is pretty much welfare for space nerds.

Henry’s suggestions were more or less what I’ve been saying here, so I agree with them 100%. Quoting Henry (emphasis again mine):

– NASA should let go of controlling their own space transportation from start to finish. They should make an exploration plan based on a variety of existing commercially available boosters, then put the entire ground-to-orbit leg of their new deep space missions out to bid.

– NASA should lay off and/or BRAC large parts of their Shuttle/Station establishment as Shuttle is shut down and Station completed, rather than again compulsively trying to “keep the team together”. It’s been a long time since this team had a winning season, the payroll is crippling, and the game has changed. Rebuild from the ground up.

– NASA should let go of numerous arbitrary and/or dated “this is best” prejudices the organization has accumulated over the years. Old NASA (as someone once said of a notoriously inbred european royal house) forgets nothing, and it learns nothing.

Henry then went a little into what he saw as being the ramifications of a commercially launched Earth Orbit Rendezvous-type system. Here’s where I have to pick on quick nit. Henry mentions that due to the fact that hydrogen is “hard to store for long”, if you insist on using only the fastest transfer orbits, the launch windows are short, and that can be a big problem. This is a more intelligent (but still slightly flawed, IMO) variant on a commonly heard complaint that if you go with on-orbit assembly or refueling, that if a single launch fails, you lose your entire mission. If you look at the real numbers, the problem just isn’t as big as most people assume. Borrowing from Bruce Dunn’s analysis, a properly insulated tank in the size range we’re looking at will probably have less than 1lb/hr of LH2 boiloff, and about 3/4 that of LOX boiloff. That’s not a lot. Over a full month we’re talking about less than 4% of the LH2 boiling off, and less than 0.5% of the LOX. That ends up coming out to only about 1% of the total propellants after a full month of delay. Even if you assume the worst case numbers they were showing (that required less insulation), you’re still only talking about something like 4% of the total propellant boiling off. And if you use a heat exchanger like Bruce suggested to use some of the LH2 boiloff to cool the LOX tanks, you can get those numbers back down to 2% or so of the total propellant volume over a full month worth of delays. Extra tankage isn’t free, but most propellant tanks weigh about 1lb for every 10-100lbs of propellant (depending on the density of the propellant).

What that all means is that even if you insist on using LH2 (which isn’t neccessarily as stupid of an idea as Henry makes it seem to be–I’ll probably write a future blog entry about the pros and cons of LH2 for cislunar flight), the boiloff issue just isn’t that rough. It isn’t a real argument for not doing on-orbit refueling. A trivial design expense up-front can more than handle making sure the tanks have sufficient margin. Doing slower multi-burn trajectories to open up more launch windows, or going with a more space storable fuel like propane or methane make the problem even smaller, but even if you insist on the fast flights, and the LH2….you get the point.

Anyhow, that’s enough for now. Henry’s article is a good take on the whole situation. What a bloody waste.

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Jonathan Goff

Jonathan Goff

President/CEO at Altius Space Machines
Jonathan Goff is a space technologist, inventor, and serial space entrepreneur who created the Selenian Boondocks blog. Jon was a co-founder of Masten Space Systems, and is the founder and CEO of Altius Space Machines, a space robotics startup in Broomfield, CO. His family includes his wife, Tiffany, and five boys: Jarom (deceased), Jonathan, James, Peter, and Andrew. Jon has a BS in Manufacturing Engineering (1999) and an MS in Mechanical Engineering (2007) from Brigham Young University, and served an LDS proselytizing mission in Olongapo, Philippines from 2000-2002.
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16 Responses to Various Thoughts about the ESAS report

  1. Mark says:

    You know, Jon, calling something “fallacies” without saying why is not exactly cricket.

  2. Jon Goff says:

    Yeah, I was expecting to have enough time last night to write a few more entries, but something else came up. I do still intend to pick a few nits with your recent entries, but it’ll have to wait till I have a bit more time. 🙂

    All that said, I definitely toned down my comment about your site before I posted. I may disagree with you, and I may enjoy making fun of some of the silly stuff you say, but at least I can try being relatively tactful about it.
    ~Jon

  3. Anonymous says:

    Jon,

    There was a key sentence in Griffin’s comments that I think everyone in the alt.space crowd has missed. Griffin compared funding this program with funding the Navy. Now the USG certainly wouldn’t give up owning proprietary warships in order to let entrepeneurs conduct US Naval operations, even if it would be billions cheaper. Unless this was just a toss-off comment to drum up Congressional support, if NASA truely thinks of itself like that, then there is no way an economic argument is ever going to convince NASA to let private companies conduct significant space operations on the USG’s behalf.

    jak

  4. Mr. X says:

    The impression I’m getting from space enthusiasts (at least the ones who keep blogs) is that they’re not very smitten with the Griffin plan.

    Technologically, I think the Griffin plan is the best we can do with our current capabilities. It’s the economics of the plan that are totally messed up. Unless a significant degree of private entrprise is worked in (and this can be added at a later date, when the program is far along,) the plan will never be sustainable.

    Ultimately, we’re having to do things Apollo-style because we never took the time or money to build a real RLV. Even Delta and Atlas would have been fine, seeing as how LockMart and Boeing are both hurting for sales and could use a few moon launches to boost their bottom lines.

    We have learned a few things since Apollo, though. This time, the SRB’s will be reused, unlike the totally-disposable Saturn. Capsule reuse is also possible. Longer stays on the moon and bigger crews are also good.

  5. Mark says:

    Well, Jon, there you go again. Now the things I say are “silly.” You don’t explain why this is so.

  6. Mark says:

    “If NASA truely thinks of itself like that, then there is no way an economic argument is ever going to convince NASA to let private companies conduct significant space operations on the USG’s behalf.”

    That of course is wrong. the military often contracts with commercial charter companies for air transportation. NASA itself is going to throw open ISS resupply/crew transfers to the commercial sector.

  7. Ed says:

    Mark, you really ought to allow comments on Curmudgeon’s. Then if you come up with a good point we can give you a pat on the back and an “attaboy”; and if you say something silly we can point that out too. At least then we can have the discussion proximal to the post under discussion, not here or my blog or transterrestrial or backoffgov.

    And Jon, yeah, what fallacies and silly stuff do you want to point out about what Mark has been saying lately?

    As for what I have seen lately, this stuck out: “Second, I have a hard time understanding how the return to the Moon somehow precludes building a space elevator.”

    The return to the moon does not preclude it. NASA’s chosen path does; the heavy lift launcher will cost 10 billion dollars to develop, about the same as Brad Edwards estimated for the space elevator. NASA can do one or the other, but not both – not with the current budget.

    Once NASA does develop their heavy lift launcher, they have a disincentive to develop a space elevator, even though a space elevator would be orders of magnitude better (both in terms of total mass delivered to orbit per year and in $/kg to orbit). After all, they would have this shiny brand new system, which cost 10 billion dollars to develop, which would immediately be obsolete as soon as the space elevator came online.

  8. Phil Fraering says:

    Ed wrote:

    “Once NASA does develop their heavy lift launcher, they have a disincentive to develop a space elevator, even though a space elevator would be orders of magnitude better (both in terms of total mass delivered to orbit per year and in $/kg to orbit). After all, they would have this shiny brand new system, which cost 10 billion dollars to develop, which would immediately be obsolete as soon as the space elevator came online.”

    I find myself doubting that the agency (or society) that has shown itself incapable of building a relatively simple functioning RLV is suddenly going to be able to build a space elevator, especially given the latter’s much larger initial size and the greater relative difficulty (compared to one or two stage RLV’s) of doing incremental testing and development.

  9. Mark says:

    Ed – The last thing I want is a government agency to do is to build a space elevator. Just as the return to the Moon can be seen as this century’s Lewis and Clark Expedition, a space elevator would be the transcontinental railroad. The way one builds a “railroad to the heavens” is to put together a package of tax breaks, loan guaruntees, and even lunar land grants to create an incentive for the private sector to build the thing.

  10. Ed says:

    Mark, I have no problem at all with the tax breaks and loan guarantees you mention. And I too would rather that NASA did not actually build a space elevator; at best I’d like them to concentrate on the second A in their name, perhaps coordinating private efforts.

    The lunar land grants would be problematic, since the USA doesn’t own the moon.

  11. Mark says:

    “The lunar land grants would be problematic, since the USA doesn’t own the moon.”

    Another thing I favor is revisiting the Outer Space Treaty to, if not change that, at least set up some kind of international convention that allows for the actual selling of lunar land grants to private entities.

  12. Jon Goff says:

    Jak, Mark,

    Jak said: “If NASA truely thinks of itself like that, then there is no way an economic argument is ever going to convince NASA to let private companies conduct significant space operations on the USG’s behalf.”

    Mark: “That of course is wrong. the military often contracts with commercial charter companies for air transportation. NASA itself is going to throw open ISS resupply/crew transfers to the commercial sector.”

    Mark’s right on the first part of this. The military quite often will buy services from commercial providers when they exist. The problem I have with Griffin’s architecture is that while they are offering the small carrot of ISS deliveries, they’re trying to do the rest of the Earth-to-Orbit transportation themselves instead of using existing launch providers.

    Delta, Atlas, Sea Launch, Proton, Soyuz, Ariane V, all of these exist, all of them have a good or decent trackrecord. They aren’t the most cost effective in the world, but they’re cheaper than NASA designing, building, and operating new vehicles. Most of those are capable of launching a full-sized unfueled EDS, or an LSAM, or an unfueled CEV. NASA really doesn’t need to build their own launchers to do this. It’ll require a little bit bigger margins on their part, and developing the capability of transfering cryogens on orbit. But those should be substantially cheaper than the $15B or so earmarked for the two HLVs. I just don’t see why they insist on going with their own launchers when earth-to-orbit transportation is a commercially available, off-the-shelf item. There is nothing they’re trying to do that can’t be done with existing boosters. All I can guess is that Griffin is being pushed into a corner by politicians who care more about pork than about actual lunar exploration.

    If they were serious about going back to the moon, they wouldn’t be trying to develop new vehicles when existing ones are just as good. They’d be developing the translunar and lunar landing vehicles instead.
    ~Jon

  13. Jon Goff says:

    Ed,
    I have to agree with Mark and Phil. Having NASA build a space elevator would be even dumber than the ESAS plan (and that takes effort). I’d much rather see them spend the money they would on building those vehicles to design their capsule and their EDS and their LSAM, and just buy dozens of flights from Boeing and LM, and if SpaceX delivers on their Falcon IX buy from them too. Heck, for propellant launches, buy on the international market. They could afford to have a man back on the moon within 5-10 years, and have a much larger and more robust program if it weren’t for their “not invented here” gotta-build-me-my-big-ol-rocket fetishes.
    ~Jon

  14. Henry Vanderbilt says:

    Hi, Jon – thanks for the kind words, and apologies for the delay in responding. One reason we don’t toss big rocks into other people’s ponds very often is the large amount of followup work it generates – we’ve been getting feedback (generally positive) from some really surprising places.

    Regarding the occasional familiar-seeming idea popping up in our piece, well, we’ve been reading every bit of data and opinion on ESAS we could find, and thinking reeeeeally long and hard, since June. On any given point, your guess is as good as ours between our having picked your online brains and Great Minds Thinking Alike. (Mind, we’ve noticed over the years that there’s a LOT of the latter going on in matters like this, where a lot of smart people are following the same issues very closely.)

    As for any particular technical approach we might seem to have pushed in the “longish digression into consequences” section of Space Access Update #112, our main purpose there was to list and counter the more obvious reasons NASA might claim for the ESAS approach being the only practical one. Any specific alternatives alluded to were in aid of that goal – the only specifics we formally advocate are the three points listed earlier: Commercial rather than NASA boosters, BRAC the standing army, ditch much conceptual baggage.

    That said, I’m highly tempted to take off my Executive Director hat for a while and get all tech-weenie over liquid hydrogen with you – it’d be fun! But I don’t have the free hours to seriously get into it. The short version there though is, cryo versus non-cryo is not the question, LH2 versus everything else is. Unlike other cryos of interest, LH2 is too cold for no-boiloff long-term storage via passive cooling to work; unlike other cryos LH2 tank mass fraction is appallingly bad – look at the shuttle ET as being towards the best-case, big tanks with low surface-to-volume ratios and high boiloff allowable thus low insulation requirement. By my hasty back-of-the-envelope numbers, the ET LOX tank masses less than 1% of the LOX it carries, the ET LH2 tank masses greater than 12% of its LH2 content. Factor in smaller volume tanks and longer storage requirements for a hypothetical deep-space mission application, and LH2 tank mass fractions rapidly get up to where other fuels could start to look like a reasonable tradeoff. But I wasn’t going to go all tech-weenie, was I? [grin] (Don’t forget higher LH2 engine mass for a given thrust requirement too in the tradeoffs…) Regardless, the main point was that NASA’s LH2-uber-alles bias is open to question, not that LH2 might not have a place at all. In particular, as you point out, an on-orbit propellant depot might make LH2 an attractive choice for propulsion outbound from LEO.

    all the best

    Henry Vanderbilt
    Space Access Society

  15. Jon Goff says:

    Henry,
    Thanks for the comments, I wrote a bit of a reply about the hydrogen question as a separate post.
    ~Jon

  16. murphydyne says:

    Mr. Vanderbilt,

    Thanks for the SAS Update #112. Like Jon, I had that eerie feeling of “You know, that’s similar to something I remember posting on some board or another.

    Unfortunately, it sounds like y’all did more homework than NASA did.

    I’ll be getting in touch about the 2007 ISDC here in D/FW after the current brouhaha calms down a bit.

    “kadet” ken murphy”dyne”

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