Some Constructive Suggestions for NASA

It’s been a little while since I last posted anything to the blog. Michael Mealling suggested that after the RTM articles, it might be a good idea to take a break for a week or so, in order to not burn myself out. Between that piece of advice, the fact that the ideas I wanted to write about last week are only about half-way baked, and how many trips we needed to make to our remote test site for my day job last week, blogging has been pretty light. We’re still going to be pretty busy over the next few weeks, but I’ll try to find some time to post occasionally.

Anyhow, I’ve noticed that a lot of my posts recently have been rather negative about NASA, and not particularly constructive. While I probably am not going to stop bringing up what I see as legitimate concerns with NASA’s policy choices, I figured it was about time to post something a wee bit more constructive.

I wanted to take a few minutes to briefly describe one possible way that NASA could better organize it’s return to the moon. It probably is still a far cry from perfect, probably isn’t as purely libertarian as I would prefer, and may not have a chance in heck of ever happening, but I figured it would be worthwhile to put a few thoughts on the table.

A Modest Proposal
The basic idea is to have NASA change the lunar transportation architecture from a closed, shuttle-derived system, to an open, commercially launched architecture.

Instead of developing two new heavy lift launch vehicles, NASA should go with an architecture that dry-launches the various components, and then refuels them on-orbit using fuel modules boosted by existing or future launch vehicles. The lunar lander module would be a single stage lunar orbit to surface and back vehicle instead of the two stage, Apollo-esque system they have now.

Potential Benefits
By using on-orbit refueling, and by having the lunar lander return to lunar orbit, the vehicles could be reused multiple times, greatly reducing the costs per mission. This style of architecture is also more able to take advantage of lunar derived propellants if they become available.

By putting the propellant launch needs out on the open market, the price of launching it will be driven down substantially, allowing for more ambitious projects. There is a current glut in the 10-20 ton to LEO launch vehicle market, and prices would drop considerably with higher utilization. The high launch prices currently bandied about by SDV supporters are high precisely because these vehicles are used far less frequently than the infrastructure was designed to handle. Higher flight rates would drive the per launch prices down substantially compared to their current place, and with competition from companies like SpaceX, launch prices might actually start getting close to where they need to be for a sustainable architecture.

This architecture has the benefit that it can rely on existing launchers, while still being able to take advantage of future lower-cost launch vehicles if they become available. Between Atlas V and Delta IV, there is plenty of currently idle US launch capacity that could be used. SpaceX with their Falcon V and IX could eventually be tapped, as could Zenit, Proton, Soyuz, or Arianne V if the government were willing to purchase launch on an international market. This could also encourage future players with RLVs or low cost ELVs to enter the market, without putting them on the critical path like Griffin is afraid of. In contrast, if someone came up with a magical RLV that cost $50/lb to orbit next year, NASA would have to completely change its whole architecture to benefit from it.

There is an additional benefit in that by going with multiple suppliers, the program has less programatic risk of any one supplier going out of business or having to stand-down their launcher due to a launch accident. Not to mention avoiding the programatic risk of having the sole launch vehicle canceled due to cost, like the Saturn V.

If NASA doesn’t trust the commercial sector to provide on-orbit refueling capacity, they could develop a docking and propellant transfer module that could be integrated into otherwise dumb propellant tanks that could then be launched by commercial providers. The commercial provider would launch the tank with module into LEO, then the module itself would perform the docking and propellant transfer maneuvers, followed by a deorbit burn after the propellant has been transfered. A propellant depot in LEO isn’t required, but might make logistics easier in the long term. While using a NASA designed docking and propellant transfer module is probably not as cost effective as having an all commercial system with NASA only defining the docking interface, it at least gets rid of the “last mile problem” and the difficulties of dealing with NASA proximity ops bureaucracy.

Anyhow, this is just a few initial thoughts. I may flesh out various parts of this as time permits, but I wanted to put the basic idea out in the open for some discussion.

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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.
Jonathan Goff

About Jonathan Goff

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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11 Responses to Some Constructive Suggestions for NASA

  1. Dave Salt says:

    Jon, what you say makes sense if one of the prime objectives is to nurture/foster the growth of commercial space activities. Unfortunately, it’s become all too apparent that NASA has no such directive from the VSE and, from what I read in its charter, never has had since its formation.

    NASA is basically a self-serving organisation that views commercial space as merely a tool to help it achieve its own goals — this is not a criticism, just a statement of fact. However, this is the exact opposite of the government’s approach to civil aviation in the 1920’s and 1930’s, where the prime objective *was* to nurture/foster the growth of commercial aviation.

    So, as far as I can see, the only thing that would get NASA to go the way you suggest would be to get a new presidential or congressional directive that calls specifically for actions to nurture/foster the growth of commercial space activities.

    Of course, such a major task doesn’t have to be given to NASA. An existing or new branch of government may well be better suited to the task.

    Dave

  2. Juan Suros says:

    Launching dry spacecraft and fueling them in orbit is a great idea, solving the cart before the horse problem of not wanting to pay for development of a heavy lift launcher before a market exists, but are we missing a possibility?

    I’ve wondered from time to time why we don’t consider the possibility of In-Situ resource gathering in low orbit. A 200km orbit (7.78km/s) is unstable because of collision with atmosphere. Capturing the atmosphere rather than bouncing it off will exert exactly the same amount of drag on a spacecraft’s orbit, won’t it?

    Run a high capacity/low performance ion engine with an input of hypersonic gasses and output of gasses at low enough speed to capture with adsorbents or some sort of pump. Thomas J. McGuire did most of the necessary math for a MIT Master’s thesis a few years ago, and Jordin T. Kare has written a bunch of papers on beaming power that could power a satellite of this type.

    Just a thought. Someone with a better library than google could probably find more examples of this idea.

  3. Dan Schrimpsher says:

    I like it. I have a little different take though. (No I am not dead, just got promoted 🙂

    Agile Space

  4. Jon Goff says:

    Dave,
    I agree that NASA would be more likely to choose a more commercial-oriented approach if it were a primary objective of theirs. The sad thing is that the speech that became the basis for the VSE, and several of the other documents that came out of the Whitehouse regarding the program all did state that encouraging commerce was part of the rationale behind the VSE. The other thing that bugs me is that in spite of all this, many of the VSE supporters still try to claim that somehow NASA’s return to the moon is going to be some huge boon for commercial space.

    ~Jon

  5. Jon Goff says:

    Dan,
    Good article. Methinks you need to install trackbacks like I did. I’ll just have to blog a response…..
    ~Jon

  6. Iain McClatchie says:

    Why move the fuel from one tank to another? The only reason I can think of for this is if a single large tank would be significantly lighter than several small tanks. Maybe that’s true if the big tank doesn’t have to support fuel during launch, and isn’t a pressure vessel. But I don’t see any trip in the next 20 years being done with inflatable tanks.

    ISTM you should boost a high-value dry vehicle with no tank and maybe no engines. Without tanks and engines the high-value part can be a lot heavier and still fit on one high-cost booster. Let the commercial launch folks boost several completely fuelled tanks, and connect those directly to the dry vehicle.

    Going to Low Mars Orbit from LEO and back will require a delta-V of at least 6.1 km/s (using this handy diagram). That number assumes aerobraking (yikes!) That’s enough that using separate stages for the Earth-Mars trip and Mars-Earth return would make sense. I’d let the supposedly unreliable commercial folks boost and assemble the entire Earth-Mars stage, and the return stage too, and send the crew vehicle up as a Shuttle-C launch (100+ metric tons).

    Using SpaceX’s posted technology and launch costs, I figure they could put a 168 mton return stage and 720 mton Earth-Mars stage in LEO for less than $2 billion… without developing new technology, without improving their launch costs, but scaling up their LOX-RP1 technology significantly.

  7. Jon Goff says:

    Ambivalent,
    Interesting ideas, but there are a few problems with them. The key reason why I suggested propellant transfer instead of tank transfer is the increased flexibility. If you have several different companies boosting propellant on different launchers, each one of those launchers will have a different payload capacity. This means you have to pick one of the following options:
    a) Design your transfer stage to somehow be able to use tanks of differing sizes (relatively tough).
    b) Specify a standard tank size or two, and live with the fact that you’re shutting out small launchers, and wasting capacity on big launchers.
    c) Pick one or two launch providers only and go with tanks sized to fit their vehicles.
    The problem I see is that all of these cost extra money and/or cost you flexibility. What happens if you have a new booster become available smaller than your standard tank size? It’s an interesting idea, but IMO, not yet very practical.

    As for your Mars vehicle ideas, they have a bit of merit, but once you’ve gone with small launches for the propellant, do you really still want to require a Shuttle C for any of the hardware? Why not break things down into reasonable chunks? Flying a Shuttle C just for the crew module launch is actually the worst of both worlds. You still have to pay the infrastructure and fixed costs of the Shuttle C, but you also have to pay all the costs of using the smaller vehicles for fuel (while losing most of the benefits).
    ~Jon

  8. Dave Salt says:

    Jon, I agree that there have been some nice words about encouraging commercial space. The problem is that they’re buried in the margins and don’t form part of the basic rationale.

  9. Jon Goff says:

    Dave,
    True enough. Had commercial development been more central to the program, we probably wouldn’t be having this discussion. I’m almost done harping on NASA, I’ll probably finish up with a few more posts, wash my hands of the mess, and start focusing on how commercial space groups should be doing things.

  10. kert says:

    The key reason why I suggested propellant transfer instead of tank transfer is the increased flexibility.

    Like i already discussed elsewhere, for all the pros that propellant transfer has over dockable tanks, theres at least one drawback: your transfer stage, including its fuel tank, will be limited by payload size of largest available launcher on the market.

    As anything heading from LEO to lunar soft landing will be approximately six parts propellant and one part payload this is a significant limitation.

  11. Iain McClatchie says:

    Jon,

    Propellant transfer vs. tank transfers: I think the issue of maximizing the propellant launched by each launcher is a red herring. You’re thinking about the problem from the point of view of the launch company. They are the supplier. Suppliers in competitive industries don’t generally dictate product envelopes.

    If private launch companies want to compete, they’re going to have to standardize their payloads. There is no competition if my 1500 kg LEO satellite can only go on one launcher at a reasonable price, because everything else is too small or too big. Since NASA and the DOD are major consumers of launch services, they are in an excellent position to dictate standard payload sizes for private launch companies to target.

    If payloads are standard sizes, the problem of integrating tanks from multiple launch vendors is a non-problem. And, if t/Space wants to use ten launches to put up one standard propellant tank by using propellant transfer from a reusable vehicle, more power to them. They can try the economics of that approach versus heaving a full tank with a single shot. I’m sure if one approach is better, the other competitors will copy it.

    As for using Shuttle C for the main crew vehicle… I’ll admit I don’t know enough about breaking up such a vehicle. Obviously something can be done, witness ISS. But those interfaces are heavy, and they’re making the entire round trip (boosting the size/cost of the LEO-Mars and Mars-Earth stages) without any obvious functionality. A heavy lifter using existing SSMEs and SRBs, with a cargo pod where the shuttle sits now, looks like a pretty cheap development to me. But I’d engineer it assuming 10 launches over the lifetime of the design.

    Iain

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