Random Thoughts: Pre-Depot EELV 2-Launch Unmanned Missions

A couple months ago, I had a friend run an interesting idea past me for a way of soft-landing serious sized payloads on the moon using existing launchers, even before full-fledged depots are operational. After looking at the idea, I realized it also had the potential for even allowing manned lunar missions. While I think that full-fledged depots offer you much greater possibilities, I figured these ideas were worth a quick airing on the blog.

For sake of splitting things up, I’ll discuss the unmanned concept my friend came up with int this post, and my next post will take the idea from there to manned applications.

Pre-Depot Dual Launch Unmanned Concept

My friend’s pre-depot lunar architecture concept would use two of the larger EELVs–either Atlas V 55x’s or a Delta-IV Heavies or a mix of both. The first launch would put a single-use LOX-tank and the second launch would lift a partially-fueled Lunar Lander Centaur and the payload.

DualLaunch

Payload 1: Single-Use LOX Tank, Payload 2: Departure Centaur and Payload

The single-use LOX tank would be based on the Centaur stage’s LOX tank, and would include a sunshield, and a docking port. It would likely use the upper stage to spin up the LOX tank (similar to Frank Zegler’s LOX-only depot concept he discussed on the propellant depot panel we had at Space Access ’08). By prechilling the LOX before launch, and using a sunshield, the LOX tank could actually afford to wait for over a month without self-pressurizing to the point where it would need to vent.

The Centaur LOX Tank as the Basis for a Single-Use Precursor Depot

The Centaur LOX Tank as the Basis for a Single-Use Precursor Depot

The Lunar Lander Centaur would be similar to the LM/ULA horizontal landers we’ve discussed on the blog, but with slightly stretched tanks, and only a partial LOX load. The Lunar Lander and payload would dock with the prepositioned LOX tank, transfer propellants, and then head out. The Centaur would perform TLI, LOI, and the descent, with the lander kit providing the actual soft-landing. The end result was that with two stock Atlas V 552’s, you could place the Lunar Lander Centaur and about 8000lb of payload onto the lunar surface.

Centaur-Derived LPRP Robotic Lander

Centaur-Derived LPRP Robotic Lander

Alternately, if you left off the the lunar mission kit and just used the stretched Centaur as a interplanetary departure stage, you could loft pretty impressively big missions. For instance, you could launch payloads to Venus or Mars that would be 4-4.5x bigger at injection than Mars Science Laboratory of the Magellan Probe. And for high velocity missions like New Horizons, you could still inject 2.7x the payload. Here’s a chart my friend provided of payload mass versus C3 for two different concepts (one using two stock Atlas V 552’s, one using two Delta-IV Heavies with the new RS68A upgrade that should be in service by 2011):

The Performance of Dual-EELV Launches for Interplanetary Missions

The Performance of Dual-EELV Launches for Interplanetary Missions

Now, admittedly this is overlooking the docking part of the propellant transfer problem, so you’d end up spending at least some extra mass handling that, but that would still leave some fairly impressive capabilities. Tomorrow I hope to show how you might be able to extend this idea to performing realistic, near-term manned lunar missions.

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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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20 Responses to Random Thoughts: Pre-Depot EELV 2-Launch Unmanned Missions

  1. kert says:

    Hmm, what could be done using two Kestrels ?

  2. Xplor says:

    Seems like a very straight forward, affordable concept. I wonder if the first large lunar payload could be accomplished for the same price as the $1B gimmick called Ares I-X?

  3. Anonymous says:

    Jon,

    For lower cost and risk, United Launch Alliance (ULA) and Pratt & Whitney could build a Delta IV Heavy or an Atlas V Heavy with an upper-stage that uses 6 existing RL-10 engines or 2 RL-60 engines (i.e. similar to a ULA’s wide body Centaur or the existing Delta IV upper-stage upgraded to handle 120,000 lbs of thrust). ULA already showed NASA in 2005 (when ULA was Boeing and Lockheed) that these configurations of their heavy rockets could launch over 40-tons to LEO and 14 – 20 tons to trans-lunar injection (TLI). A 14 – 20 ton cryogenic Lunar Lander built from existing Centaur components and using the exisiting RL10 CECE engine can land 4 to 6 tons of payload on the lunar surface after being launched into TLI by this ULA Atlas/Delta Heavy launch vehicle and performing lunar insertion and lunar landing burns.

    This means that ULA could build and launch one EELV Heavy rocket and place 4 to 6 tons on the Moon within 3 years using their existing components and manufacturing capabilities. ULA would probably charge $1 Billion in NRE Costs and $500 Million for the launch, even though they do not need this much money.

    If ULA can place 4 to 6 tons on the Lunar Surface for $1.4 Billion in 3 years, then this means that ULA can place a strorable propellant lunar ascent stage comparable to the Apollo LEM ascent-stage on the moon.

    The SpaceX Dragon vehicle, which has some of the capabilities of the Apollo spacecraft, but at half the weight, will begin testing in 2010. The Dragon can be launched into a stable lunar orbit by the ULA EELV Heavy rockets mentioned above.

    The point of all the above is to say that the United States could use existing rockets, manufacturing facilities, and spacecraft to fly manned missions to the lunar surface with 2 Heavy EELVs and within 3 to 5 years for under $5 billion. The Russians are planning to use this same architecture with their newest spacecraft and rockets, but it will take them 10 years, because they have to build new spacecraft and rockets.

    The problem is that the United States is not intersted in flying people to the moon within 5 years for under $5 Billion, because the United States wants to find a way to spend $500 Billion over the next 20-years to do the same thing within 500 Congressional Districts. NASA knows this, and none of these plans are new. Dan Goldin developed similiar low-cost manned lunar landing architectures in the 1990’s, before EELV Heavy rockets made things even easier and cheaper for NASA. NASA always has to propose architectures that spend a lot of money and take a lot of time for their Congressional supporters.

    Masten Systems could probably build a 14 – 20 ton lunar lander that could launch on a single EELV Heavy to land 4 to 6 tons on the luanr surface within 3 years using components and labor already available at ULA and P&W production facilities near Masten Systems in Southern California.

    You may be over-thinking some of the technical aspects of this. Why have another company accomplish your goal on 2 EELV launches when Masten Systems can land 4 tons on the moon with one EELV launch?

  4. Dennis Wingo says:

    There is a lot of talk about 6 RL-10 engined upper stages. I wonder if the original Saturn 1 Block II design is still around somewhere?

  5. Nesrin & Marti Sarigul-Klijn says:

    Jon,

    We would be interested in your thoughts on an AIAA paper written by students and professors at the University of California at Davis. The paper is about a concept that brings the resources of multiple commercial and international partners into play. Our concept calls for the launching of multiple tugs, modified from existing upper stages, into Low Earth Orbit (LEO) from existing launch sites using existing launch vehicles. The tugs could dock nose to tail and form a train of stages that can provide the delta V for trips to the Moon, Mars, or other planets and act as a multi-stage launch vehicle that originates from LEO. See: http://mae.ucdavis.edu/faculty/sarigul/papers/AIAA-2008-7805.pdf

    We think our concept also acts as an insurance policy by eliminating the dependence on one launch vehicle or one launch site. An accident with the Aries or the proposed Direct Jupiter launch vehicle could easily stop exploration for many years while the cause of the accident is identified and corrected. Such an accident could cause abandonment of a Moon or Mars base.

    Nesrin Sarigul-Klijn, Ph.D. & Marti Sarigul-Klijn, Ph.D.
    Department of Mechanical and Aeronautical Engineering
    University of California at Davis

  6. anon says:

    The RL-10 has about a 50% throttle, so, you probably want to
    consider that in your sizing, and add some small landing engines
    that run hypergolic.

  7. Tom D says:

    I’m pretty sure that I have read somewhere that the RL-10 has been successfully throttled down to 10% thrust, but you are right that it does have to be accounted for.

    The bottom line is that it looks like a lot of human spaceflight missions are feasible with what appear to be near-term derivatives of the Centaur stage on EELVs including missions to the moon. So, why isn’t any individual, company, or country doing this yet? Am I too impatient?

  8. Eric Collins says:

    What’s the mass on that LOX tank? Would it be possible to do a couple of Falcon 1e launches to top off the Centaur stage?

  9. anon says:

    Tom

    I’m sure you can throttle a RL-10 down, if you restrict it’s max performance. P&W is trying to make the CECE engine work and are failing badly. It just won’t run stable.

  10. Martijn Meijering says:

    Anon, can you say more about CECE not working out? Is there anything that is publicly available that backs this up?

  11. KGyST says:

    I think such a scenario is the typical one to be launched by RLVs. All their benefits would be exploited: in spite of one large rocket You would launch a series of smaller ones (or a series of launches of one smaller rocket), at the cost of an in-orbit construction (or, in this case, in-orbit refuelling).

  12. Jonathan Goff Jonathan Goff says:

    Anonymous,
    For lower cost and risk, United Launch Alliance (ULA) and Pratt & Whitney could build a Delta IV Heavy or an Atlas V Heavy with an upper-stage that uses 6 existing RL-10 engines or 2 RL-60 engines (i.e. similar to a ULA’s wide body Centaur or the existing Delta IV upper-stage upgraded to handle 120,000 lbs of thrust).

    Yeah, going with a WBC/ACSE/CUS (or whatever the current acronym is) upper stage definitely would help performance a lot. Not just for the launch to LEO portion, but more particularly for all of the in-space segments. That said, I wanted to look at what we could do with existing pieces first. That way NASA can’t claim that you’re comparing paper rockets to their paper rockets.

    Masten Systems could probably build a 14 – 20 ton lunar lander that could launch on a single EELV Heavy to land 4 to 6 tons on the luanr surface within 3 years using components and labor already available at ULA and P&W production facilities near Masten Systems in Southern California.

    While I hope that MSS eventually does do lunar landers and other such things, those are still a fair ways off in the future. We’ve just barely started flying our first vehicle. I think that’s awesome, but let’s keep expectations reasonable. Gotta remember, we’ve barely added our fifth full time engineer last month. Designing a large lunar lander that can’t really be tested out easily on earth, that is going to ride on a multi-hundred million dollar launch vehicle is something for when we have more experience under our belt, a bigger staff, and more resources.

    I hope to be there some day, and I hope to throw water on your enthusiasm, but that’s how I see it. Sorry.

    ~Jon

  13. Jonathan Goff Jonathan Goff says:

    Dennis,
    There might be some design stuff around still, but it probably wouldn’t really compare with the latest work that ULA has been doing on their common upper stage vehicle. There might still be some useful lessons learned, but the Centaur guys have been designing and fielding new versions of their vehicle a lot more recently than Apollo. The most advanced rockets in the world aren’t designed in Huntsville anymore.

    ~Jon

  14. Jonathan Goff Jonathan Goff says:

    anon,
    The RL-10 has about a 50% throttle, so, you probably want to
    consider that in your sizing, and add some small landing engines
    that run hypergolic.

    I’m not sure if I spelled it out in the post, but for my calculations, I was including about 2.5mT on the lander for their horizontal lander kit, which uses hypergols and small landing engines for the final approach and landing. The stretched Centaur can actually bring almost 8mT to just above the lunar surface. If you go with a crasher stage and have your payload carry its own landing hardware, you can probably land quite a bit more than the ~8000lb I was mentioning in the post.

    ~Jon

  15. Jonathan Goff Jonathan Goff says:

    Tom D,
    The bottom line is that it looks like a lot of human spaceflight missions are feasible with what appear to be near-term derivatives of the Centaur stage on EELVs including missions to the moon. So, why isn’t any individual, company, or country doing this yet? Am I too impatient?

    Lots of reasons. The big companies are publicly traded. Which makes it legally hard for them to take large entrepreneurial risks. If they take a big risk, and lose a lot of money on it, they could probably get sued by their shareholders (at best they would probably “only” get fired). There are smaller companies that are more able to take risks, but they for the most part don’t have the money to do so. And it’s hard to raise money for doing a “Lockheed” sized project where you’re just a Masten Space Systems or an Armadillo. And it’s hard for someone at NASA to do a project like this because it doesn’t provide the port that congresscritters want.

    Another big problem is that if it’s done privately, you have to have a way of making your money back (or someone with a *ton* of money burning a hole in their philantrocapitalistic pockets). I really believe there are markets there along the way, but they will take time to develop.

    The reality is that we’ve backed ourselves into a pretty stagnant corner in this industry, and there are no easy/quick ways out. All of the actors have constraints that really hinder them getting stuff done effectively. Big industry has its hands tied by being publicly funded, small industry has it’s hands tied by being privately funded, and government has its hands tied by being Congressionally funded. There are probably ways out of this morass, but 40 years of bad policy and bad decisionmaking aren’t going to be undone in a heartbeat.

    ~Jon

  16. Jonathan Goff Jonathan Goff says:

    Eric,

    The LOX tank/disposable depot would weigh about 1mT dry and hold about 20mT of LOX. For comparison, the Centaur tanks themselves weigh about 12kg per m^3 (or about 10kg/mT LOX). That means that the tanks would be about 200kg of that, and the rest would be for a docking mechanism, sunshield, and other goodies.

    ~Jon

  17. Jonathan Goff Jonathan Goff says:

    KGyST,
    I think that for RLVs you’d really like a depot and a tug. For doing vehicle-to-vehicle propellant transfer, you do kind of want to tend towards minimizing the number of deliveries. With a depot though, you can spread the deliveries out a lot more, since it can easily afford more and better cooling systems, more robust docking hardware, and probably a tug to minimize the odds of something getting damaged by the tankers.

    ~Jon

  18. Anonymous says:

    Jon,

    Masten Space Systems (MSS) could build the before-mentioned 14 – 20 ton lunar lander using ULA and P&W’s exisitng components, labor, and facilities if given $300 Million over 3 years. MSS would be the lead contractor, and could hire as many oversight engineers as the budget would allow to manage ULA and P&W.

    ULA and P&W could not do this themselves, because their corporate structure is designed to spend as much money within overhead as possible.

    The RL10 CECE engine can be tested with Liquid Methane, and XCOR could probably build a 10,000-lb thrust liquid methane engine and flight weight liquid methane and LOX tanks for you in Mojave. Scaled Composites or SpaceX could probably build the flight-weight structure for you if you paid them enough money (on a fixed price basis).

    The point is that whatever amount of money or resources MSS needs to build this 14 – 20 ton lunar lander to launch on a single EELV Heavy would be much less than the $100 Billion program that NASA is executing to go to the moon. Another point is that this capability already exists within industry, so this can all be done without NASA if some entity, like DARPA, decided to go around NASA to do this.

    If the investors who lost $6 Billion on the Iridium bankruptcy in 1999 invested that $6 Billion in sending men to the moon in 2009, then they probably would have enough money to do this without involving NASA or others.

  19. Xplor says:

    “KGyST/Jon
    I think that for RLVs you’d really like a depot and a tug. For doing vehicle-to-vehicle propellant transfer, you do kind of want to tend towards minimizing the number of deliveries. With a depot though, you can spread the deliveries out a lot more, since it can easily afford more and better cooling systems, more robust docking hardware, and probably a tug to minimize the odds of something getting damaged by the tankers.”

    Actually, this LO2 launch then mission approach is ideal for the partnering of small, reusable rockets (and assume low cost at high launch rates) and larger EELV class rockets. LO2 is relatively dense, ~70 lb/ft3, and thus fits very well within the tight confines of most reusable rocket designs. The EELV’s can readily launch the in-space/lander stage with the large LH2 and payload volumes.

    While the market can start with EELV’s to allow near term missions and market development. The obvious intent is that a large market for propellant (namely LO2) will foster the robust development of new low cost rockets. These may be reduced cost Atlas’s, or maybe Falcons. Maybe the promise/vision of reusable rockets could finally be realized!

    The competition and continuous improvement enabled by propellant depots is what will open space for sustainable exploration, colinization and expansion of human kind.

  20. Jonathan Goff Jonathan Goff says:

    Xplor,
    I definitely agree that propellant deliveries would make a great market for new low-cost ELVs and RLVs as well. However the idea of just delivering a LOX tank, and letting the payload dock with it and fill up works best when the number of tanks is kept to a reasonable minimum (I wouldn’t go much past two or three). Once you get past that point, having an actual depot (even if it’s LOX-only) starts making a lot more sense. So, for EELV-sized or near EELV sized launchers, the “just drop off a tank” approach probably would be a good starter, in order to really open the door for RLVs (which will likely be smaller), but an actual depot plus a tug start making things a lot better. You can go for a much smaller RLV (down in the 1000-2500lb to LEO class) if you have a tug and a depot than would make sense if the RLV were trying to drop off a whole bunch of LOX tanks.

    ~Jon

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