Shuttle Derived Sillyness Part II: The Case Against Heavy Lift

Sorry I don’t have quite as pithy title this time. My creative juices only go so far some days, and I wanted to leave some for the actual article. Nothing more Dilbertesque than spending so long trying to come up with a clever article that you never get around to your point…

Also sorry that I wasn’t able to finish this up sooner. We’ve been really busy the past few days trying to wrap up the igniter development and qualification at work to the point where we can start rocket engine testing. There’s also been a few lovely little flamewars on the SFF’s Space Arena BBS that I willingly allowed myself to be dragged into.

That said, I want to comment on a commonly held belief in the space enthusiast crowd. That belief is that in order to do anything important in space, you need a Heavy Lift Vehicle. Something big, and cool like a Saturn V. While I think there may become a time where the cislunar economy develops to the point where there is sufficient traffic to justify Heavy Lift Vehicles, I don’t think we’re anywhere near that point at the present.

One of the common reasons why people tend to think HLVs are neccessary for manned
lunar travel is that they seem to think that the only alternative to HLVs for lunar missions is to do extensive on-orbit assembly. They then point to the experience with the ISS and use that to show that they think on-orbit assembly is just too expensive and difficult. There are a couple of problems with this argument:

  1. Most of the mass required in LEO for a lunar trip is the propellants. If you count lander propellants too, you’re probably close to 75-85% of the total mass in LEO. Propellants are easily divisible into smaller segments, and don’t have to be launched at the same time as the rest of the vehicle.

    Large-scale transfer and storage of cryogenic propellants is still a poorly developed field, but one that is absolutely critical for the development of a spacefaring society. Unless you develop the capability to refuel in microgravity (whether that takes place in LEO, GEO, GTO, LLO, or at the L-1 LaGrange point doesn’t matter), it will be difficult or impossible to reuse lunar transfer vehicles, and it isn’t really possible to have a meaningful cislunar economy if you throw away your vehicle after every flight.

    What this means is that most of the “on-orbit assembly” is entirely in the form of docking and transfering propellants, not astronauts doing spacewalks connecting cables and turning bolts.

  2. Most lunar missions, and almost all manned lunar missions have natural “break points” anyway. What I mean by this, is that there are natural places where you are probably going to want to split the spacecraft anyhow. For instance, in the Apollo program, there was a Command Module, a Service Module, and a Lunar Excursion Module (which itself had a descent and ascent portion). Every mission flown required a rendezvous and docking maneuver anyhow to mate with the LEM in the proper translunar injection configuration. This is a natural break point. The LEM didn’t have to be designed to be launched on the same vehicle as the CM or the CSM.

    Future lunar missions are likely to differ quite a bit from the methods taken in Apollo, but that doesn’t mean that they don’t also have logical break points. If one wants to reuse their cislunar architecture, some good break points might be staging at L1 or in a Lunar orbit. The lander probably can and probably ought to be a separate spacecraft from the transfer stage, which implies that there isn’t any particular reason why it should be launched at the same time as the transfer vehicle. In fact, there’s no good reason why the lander even needs to be flown on the same lunar transfer vehicle as the passengers or cargo.

  3. As can be seen from those previous points, almost all of the “on-orbit assembly” is going to be of the rendezvous and docking form. We’ve been doing this since the time when most engineering was done with a sliderule. How hard can that really still be using modern technology?
  4. Even on-orbit assembly of the ISS sort doesn’t have to forever remain difficult or impossible. A lot of the cost of ISS assembly labor stems from the high cost of getting into space in the first place. If that can be lowered, and made more frequent, the relative costs and difficulties of on-orbit assembly can be greatly reduced.

There are some operational drawbacks to an earth-orbit rendezvous architecture, that I’ll probably delve into in a later post. However, as one can see from some of the points I’ve made already, there are some very good reasons for not going with an HLV. A quick summary is that:

  • Going with an HLV discourages the development of technologies and procedures that will be needed anyway before affordable cislunar travel is possible
  • Going with an HLV will ensure that payloads are designed intentionally for the HLV, and not for anything smaller or cheaper
  • Going with an HLV requires you to actually develop an HLV, which in spite of Griffen’s crack about already having an HLV, will actually take significant time and money to field (more on that one later)
  • Going with an HLV means that you can’t take advantage of reductions in launch prices that occur as the private sector gets moving
  • Since NASA will probably try to design most of their payloads to be launchable only on an HLV (to justify its existance), any launch failure of the system will ground the whole program
  • Going with an HLV will require substantial capital costs for upgrading launch infrastructure
  • Going with an HLV will mean that NASA can’t benefit from lower prices due to other customers paying their share of the amortization of the flight systems
  • Going with an HLV means that NASA is spending taxpayer money to compete with existing and planned commercial vehicles in spite of laws forbidding it to do so
  • Going with an HLV derived from the Shuttle perpetuates that wasteful and expensive bureaucracy associated with that failed program, and insures that NASA will continue to be seen as a make-work scheme for rocket nerds

I think that’s enough dead horse beating for today.

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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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8 Responses to Shuttle Derived Sillyness Part II: The Case Against Heavy Lift

  1. Kelly Starks says:

    a couple nits and a question.

    Most of the advantages of not having a HLV don’t apply to NASA, nor the disadvantages. They are a government agency needing to maintain their budget and turf, so cost cutting and commercial support are disadvantagious.

    ISS also had a lot of technilogical extra costs and difficulties – and safty issues – being built out of seperate parts assembled in place. Some major systems don’t break down into little parts well — like reactors, big base elements etc.

    As to your point that the vast bulk of the weight is fuel, thats true, but then how do you lift the huge empty craft? Or how do you store cryo in orbit, delivered over weeks? Months? by small takers?

    T/space by the way had a design that boosted itself to LEO, was then refueled and could boost (in a support convoy) to luna where it was refueled to land and luna, take off, and return to earth.

  2. Jon Goff says:

    Kelly,

    Most of the advantages of not having a HLV don’t apply to NASA, nor the disadvantages. They are a government agency needing to maintain their budget and turf, so cost cutting and commercial support are disadvantagious.

    The problem is that if they want to accomplish what they claim they want to accomplish, they will need a less expensive system. If their goal isn’t just to rapidly become some irrelevent nerd welfare scheme, they will need to get more bang for their budgetary buck. And relying on a single vehicle that has no other customers, and is government operated, is just begging for a repeat of the Saturn V shutdown that ended Apollo. SDV vehicles can be killed by Congress at any time. Vehicles that have commercial or non-VSE customers aren’t as politically fragile as that.

    ISS also had a lot of technelogical extra costs and difficulties – and safty issues – being built out of seperate parts assembled in place.

    But the reality is that you’re not
    going to be able to ship the whole
    base in one shot. You’ll have to
    do some assembly at some point, no
    matter how you slice it. But if that assembly is mostly in the form of docking, propellant transfer, and construction work on the lunar surface, I think they can avoid most of the ugly lessons we learned from ISS.

    Some major systems don’t break down into little parts well — like reactors, big base elements etc.

    Or do they? As I pointed out, it is quite possible to make a non-SDV transfer system that can delivery larger individual pieces to the lunar surface than a single-piece SDV system can. Sure, if you use an SDV to do the refueling, assembly, and staging suggestions I gave, you could put truly gargantuan single piece payloads onto the lunar surface….but how often will you need to move something that big? Is that really a need, or just a wish?

    As to your point that the vast bulk of the weight is fuel, thats true, but then how do you lift the huge empty craft?

    On an existing booster. As I thought I mentioned, you can fit quite a big transfer stage onto an Atlas V with the 5m extra long payload fairing. Big enough to deliver a package as big (or really close) to an SDV system. If you don’t insist on using LH2 as the fuel, you have even more choices.

    Or how do you store cryo in orbit, delivered over weeks? Months? by small tankers?

    With a properly designed system of course. 🙂 It all depends on the details. If you don’t have a propellant depot, you could just send up some extra propellants and allow some of them to boiloff. Or you could go for fancy-pants “zero boil-off” designs. But those things are best for fixed fuel depots.

    Basically there is some work that would need to be done, but we have a fairly good idea of what the solution will be like. I’m sure a prize or two of reasonable size could get a solution to the problem right quick.

    T/space by the way had a design that boosted itself to LEO, was then refueled and could boost (in a support convoy) to luna where it was refueled to land and luna, take off, and return to earth.

    Yeah, I like some of the things about their design, but I still think they could do better if they had a separate lander stage. I like the convoy idea….which reminds me that one of these days I need to do that writeup I promised Clark Lindsey about their proposed architecture…….

  3. Kelly Starks says:

    As to what NASA wants to or must become. Bluntly what’s #1 is keeping political supporters happy. Space doesn’t really interest them much, large numbers of jobs in districts does. Its why they never fixed the shuttle. Upgrading the shuttle would have saved them hundreds of millions a flight, and laid off tens of thousand of folks. I.E. loss of jobs in district. Space is merely a means to a end, not a end. If they contract launch services to someone else they’d save a mint – and lose the reason for the huge KSC support staff and all the associated budget – which makes JSCs huge overhead pretty hard to keep funded as well.

    Past those “practical concerns” (in the alternate reality of federal funding) Griffin also wants NASA to develop more abilities on their own. It might doom them to stay a “irrelevant nerd welfare scheme”, but they’ll be a funded irrelevant nerd welfare scheme. And if they are the only customer, they have more control over the vendor.

    ;/

    You learn a really weird sense of reality working for NASA for a while.

    As to you not being able to ship the base up in one shot — you might. The full US complement of the ISS could have been lifted in 2 lifts with a Magnum HLV. I doubt the lunar base will be that large. Though some assembly will be required.

    The big issue with the ISS was the added complexity of having to design it so it could function independently at each stage of assembly. — and of course being built in different countries, at different times, they never did a good job of integration testing.

    Anyway off topic. Big preassembled and tested (and autonomous) parts are a advantage, so minimizing lifts as much as possible is a good thing. But there are limits.

    >> but how often will you need to move something that big? Is that really a need, or just a wish?< < Well the idea was it could later be used for Mars missions which are also likely to need a few heavy lifts, but I don’t think they plan more then a few boosts. Likely less then a dozen or so. Course they didn’t fly that many Saturn-V’s either. NASA isn’t trying to establish a ongoing infrastructure, and certainly isn’t working to open space for mankind. >> you can fit quite a big transfer stage onto an Atlas V with the 5m extra long payload faring. Big enough to deliver a package as big (or really close) to an SDV system. < < Big enough to equal the front of the SDV Magnum?? >> Or how do you store cryo in orbit, delivered over weeks? Months? by small tankers?

    > With a properly designed system of course. 🙂 —

    I’m reaching through the datalines to strangle you. 😉

    In any case your now talking about fielding a orbiting fuel depot (you don’t have a lot future projected need for), to avoid fielding a big booster (you don’t have a lot future projected need for, but Marshal space center would absolutely love to develop).

    ??

    >> T/space by the way had a design that boosted itself to LEO, was then refueled and
    >> could boost (in a support convoy) to luna where it was refueled to land and luna,
    >> take off, and return to earth. < < > Yeah, I like some of the things about their design, but I still think they could do
    > better if they had a separate lander stage.–

    I don’t see how? You get a simple system with LEO – Luna surface – LEO capacity. And LEO rendezvous seems in vogue at the moment. Guess it would be a good exacuse for a station — if that wasn’t politically OUT of favor at the moment.

    >— I like the convoy idea….which reminds
    > me that one of these days I need to do that writeup I promised Clark Lindsey
    > about their proposed architecture…….

    Have to post it when your done.

    😉

  4. Mr. X says:

    There is another advantage to launching the moon ship in small pieces weighing 20-40 tonnes.

    If a true reusable launch vehicle is designed in the near future, the payload will likely be in the 20-25 tonne class. If this scenario plays out, it would be easy to substitute the new RLV for a Delta IV or Atlas V. This creates a reusable, sustainable architecture that can be used for exploring and commercially exploiting the moon.

  5. Randy says:

    I ‘agree’ with Kelly, (you can hear the internet *gasp* at that one :o) about the ‘reasons’ behind the Magnum/In-Line config HLV.
    NASAs “Mars” program is based off a modified version of Mars Direct so there is an assumption of Heavy Lift in the planning.

    On the ‘Stick’ launcher: I’ve a couple of ideas as to the ‘why’ (other than Griffens leanings or ATKs lobbying :o)

    It’s quite likely that, despite ‘illustrations’ to the contrary, LMs version of the CEV is going to be chosen. (I’ve noted a disticnt ‘drop-off’ of the buzz on Boeings capsule design since they agreed to become LMs sub-contractor on the CEV)
    Since the LM CEV is a lifting vehicle, it would have required re-design to be flown on the Delta-IV, or Atlas-V anyway.
    Since the LM design is going to mass more than expected to carry at least 6 people, (the ‘orginal CEV design only ‘really’ carried 4, and the orginal OSP design had been winnowed down to ‘maybe’ two :o)that’s probably the ‘target’ mass they are looking to put into LEO.

    On the other hand, given Congress’ lack of enthusiasm of actually funding ANY new launcher for NASA, the ‘Stick’ may be a ‘way’ of getting Congress to fund at least one new launcher. If Griffen decides on the stick and the Magnum, then he has room to be ‘talked’ into downsizing the CEV to fit Delta-IV/Atlas-V while retaining leeway to use the funds for the Stick into putting the Magnum together.

    On the gripping hand, I may just be over-thinking Washington politics :o)

    Kelly: On space storage of Cryo propellents. Check out this report on the Dunn Engineering site:
    http://www.dunnspace.com/cryogen_space_storage.htm

    There is an interesting section on space transfer of propellents in this paper on Self-Pressurized Rockets on that site too:
    http://www.dunnspace.com/self_pressurized_rockets.htm

    There has also been a bit of a ‘call’ in the last few years (both in alt.space and the ‘normal’ space advocacy community) for a Orbital Fuel Depot. So such a thing would actually make some sense to do. Along with an orbital transfer station for people and cargo (which the ISS is NOT) it would be the begining of a much better LEO infrastructure than anything currently being planned.

    Randy

  6. Kelly Starks says:

    > Randy said…
    >
    > I ‘agree’ with Kelly, (you can hear the internet *gasp*
    > at that one :o) —

    I think we just crashed the AOL owned sections of the internet?

    😉

    >— about the ‘reasons’ behind the Magnum/In-Line config HLV.
    > NASAs “Mars” program is based off a modified version of Mars
    > Direct so there is an assumption of Heavy Lift in the planning.–

    Its a very traditional NASA concept, and Griffens a traditionalist — and given the problems they had with the modular ISS – I can see NASA wanting the good old days.

    > On the ‘Stick’ launcher: —

    I nominate this for the most INSANE launcher idea seriously put forth by folks who REALLY should know better!!

    > It’s quite likely that, despite ‘illustrations’ to the contrary,
    > LMs version of the CEV is going to be chosen. (I’ve noted a disticnt
    > ‘drop-off’ of the buzz on Boeings capsule design since they agreed
    > to become LMs sub-contractor on the CEV)–

    Hey, you don’t agree to be the sub if you think your concept is #1.

    > Since the LM CEV is a lifting vehicle, it would have required
    > re-design to be flown on the Delta-IV, or Atlas-V anyway.–

    I don’t think its that lifting! And I don’t think the Stick would be that much more adaptable.

    >– Since the LM design is going to mass more than expected to carry
    > at least 6 people, —

    Yeah why exactly did Griffen double the CEV weight limits? Everyone submitted CEV proposals in the limit?

    > On the other hand, given Congress’ lack of enthusiasm of
    > actually funding ANY new launcher for NASA, the ‘Stick’ may be a
    >’way’ of getting Congress to fund at least one new launcher. —

    The Stick as a throw away? I’ll dump hte stick and take a upgraded EELV, if you’ll igve me the Magnum? Could be — I hope so!!!

    >– On the gripping hand, I may just be over-thinking Washington politics :o)

    Think the relm of Alice in Wonderland, at war, and doped out on ego and adrenaline.

    >- Kelly: On space storage of Cryo propellents. Check out this report
    > on the Dunn Engineering site:

    > http://www.dunnspace.com/cryogen_space_storage.htm

    Cool! [[Oh I didn’t say that!!]]

    Thanks. 0.5% per month (of full tanks) is usable.

    >– There has also been a bit of a ‘call’ in the last few years
    > (both in alt.space and the ‘normal’ space advocacy community)
    > for a Orbital Fuel Depot. So such a thing would actually make some
    > sense to do. Along with an orbital transfer station for people and
    > cargo (which the ISS is NOT) it would be the begining of a much
    > better LEO infrastructure than anything currently being planned.

    Agrre they would be a great idea, and a MAJOR step forward for man in space — but they would be a negative for NASA, and politically difficult to get funded after the ISS.

  7. Randy says:

    Kelly said:
    “Agrre they would be a great idea, and a MAJOR step forward for man in space — but they would be a negative for NASA, and politically difficult to get funded after the ISS.”

    (If that is actually supposed to be “Agree” we may end up crashing the internet :o)

    One thing that got my attention in the notes on the Return To The Moon confrence was that Chris Shank, (“Special Advisor” to NASA administrator, IIRCC that “Wash-speak” for mouthpiect but don’t quote me :o) indicated that the ISS will be opened up to commercial delivery services. This means even after 2010 and the Shuttle stops flying. NASA intends, (from what is being said)NOT to use the CEV for a ferry, but as a “command module” for Lunar and deep space work.
    That would fit in well with letting commercial interests take over LEO operations and getting up and down services. The CEV would still be “NASAs Vehicle” but they could then be able to buy services and rent space on an “as-needed” basis.

    Including a space fuel depot.

    As for it being ‘negative’ for NASA, I don’t see it. NASA, along with anyone else who stops to ‘tank-up’ pays for fuel which is delivered by commercial flights. That DOES mean less NASA launches but also less NASA costs, which means instead of needing “X” amount of dollars in the budget for ‘fuel’ they put “X” amount in for a Mars lander, or Lunar rover.
    (Which the big centers design and contract to be built. Makes sense in a “Washington” keep the people employed sort of way :o)

    As for the LM CEV design, yes it has ‘that’ much lift. Especially at super/hypersonic speeds. It will have the same problem as the Shuttle at launch and need to turn ‘heads-down’ to counteract. And whatever booster is going to have to be stressed for that.

    A solid motor case, (especially the SRBs cases) is ‘easier’ to stress than a liquid boosters is. But I still don’t think it has a real chance. Though you know the Congressmen from Utah are all for it :o)

    As for the ‘increase’ in mass of the CEV, I’d point out that the mass for the LM CEV ITSELF with little else was pushing the limits. They had requested, (again) a drop in requirements to only 4 people to orbit. NASA/O’Keefe said “no” and Griffen has made no move to change that.(They AND Boeing got the OSP limits dropped to “1 at least with 2 nominal” so I suppose they had hoped to get it approved)

    It could be Griffen expecting the inevetable and ‘padding’ the mass for the overweight vehicle it’s going to be. Or, as I said, he might be using it for leverage.

    While I’m thinking of it;
    Here’s the Minimum Cost Design series of articles I’d talked about before:
    http://www.dunnspace.com/home.html

    Randy

  8. Kelly Starks says:

    >> Including a space fuel depot.
    >>
    >> As for it being ‘negative’ for NASA, I don’t see it. NASA, along
    >> with anyone else who stops to ‘tank-up’ pays for fuel which is
    >> delivered by commercial flights. That DOES mean less NASA launches
    >> but also less NASA costs, which means instead of needing “X” amount
    >> of dollars in the budget for ‘fuel’ they put “X” amount in for
    >> a Mars lander, or Lunar rover.

    >> (Which the big centers design and contract to be built. Makes
    >> sense in a “Washington” keep the people employed sort of way :o)

    Your missing 2 points. First, NASA doesn’t get money in its budget, it gets spending authority for projects. If the projects underspend – the excess budget authority is lost. Secound, building Mars landers etc wouldn’t go to KSC, Marshal etc. If the money doesn’t go to the old districts, it doesn’t get those politicos support in committes.

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