Is SLS the Key to NASA’s Future or a Doomed Boondoggle?

SLS_on_pad
During the Wernher von Braun Memorial Symposium is being held this week in Huntsville, discussion has  naturally turned to the Space Launch System (SLS), the heavy lift booster being designed in the same city where von Braun and his team created the massive Saturn V.

Two very different views of SLS have emerged during the symposium. Its detractors say it is a massive boondoggle that will be squeezed out of existence by its own massive costs, low flight rate and tight government budgets. Meanwhile, the companies build the SLS say the booster’s immense launch capacity is the key to deep space exploration and could create a demand for additional missions that would increase flights rates and lower unit costs.

Former space shuttle program manager Wayne Hale, who is now director of human spaceflight at Special Aerospace Services, expressed deep skepticism about SLS during his keynote address.

Hale outlined a mixed bag of NASA successes in wake of the Apollo moon missions, noting that the agency has languished for almost 40 years as different visions for NASA have died amid a lack of funding.

The current Space Launch System – a heavy lift rocket under development at Huntsville’s Marshall Flight Center intended for deep space exploration – could soon fade away like other programs, such as Constellation in 2009.

“The current plan is fragile in the political and financial maelstrom that is Washington,” Hale said. “Planning to fly large rockets once every three or four years does not make a viable program. It is not sustainable.

“Continuing to develop programs in the same old ways, from my observations, will certainly lead to cancellation as government budgets are stretched thin. It is time to try new strategies.”

During a separate panel discussion at the symposium, representatives of companies involved in building SLS and its Orion crew vehicle took a “build it, and they will come (up with something to do with it)” approach.

One of the main criticisms of the SLS plan relates to the vehicle being developed without its range of missions, or payloads, already in place. However, that was countered by Mark Kinnersley, Director, MPCV ESM Resident Liaison, Astrium North America Inc.

“I’ve been involved in introducing a new launch vehicle and there weren’t any missions for it. But because the vehicle became available we suddenly enabled a multitude of missions. I think these ideas (new missions) will come about as SLS matures.”

Another concern is based on the cost of the launch vehicle placing a stranglehold on funding for the payloads it could launch. However, panel members believe that the capability of SLS may prove to be attractive to science organizations by vastly reducing the mission timescales for scientific exploration.

“One of the things that we forget about is that when you have a capability, people say the payloads are going to be so expensive, where are we going to get the money?” Jim Crocker, Vice President and General Manager, Civil Space, Lockheed Martin Space Systems Company noted.

“When you have that capability, you can substitute that capability for expense, or you can get some other advantage. Think about outer planet exploration, (such as) with today’s launch vehicles it can take a decade to get out to the outer planets.

“Imagine the science return with SLS, where we can get there within a few years and how that can accelerate scientific discovery.”

Speakers talked about increasing the flight rate to twice per year, which would significantly drop unit costs.

  • Brainard

    These are the people in charge of your national space program.

    Still asking i diotic questions after eight years of Constellation.

  • therealdmt

    But to fly it twice a year, what payloads would it be carrying, and how would those payloads themselves be paid for and developed?

    To fly it once every 4 years makes the cost per launch, well, astronomical.

    One solution (if forced to continue the SLS) would be to _really_ embrace international cooperation. Russia, you build a moon base. Europe, you build the lunar lander/ascent vehicles and science equipment. Japan, you build a module at the base and ground vehicles. Canada, you do the robotics. Commercial space, you do cargo re-supply, inflatables and prospecting. America, we’ll do the solar power, tracking and data relay, and lift all your parts there and provide crew transport. The SLS, along with leadership, would be our main contribution.

    And while we’re at it, there’s always a rich and growing China that might be very happy to contribute (of course, we’d have to allow them to censor the internet at the base though…).

  • Brainard

    You can grasp for straws all you want, all it does is wave your delusions around like a flag. An American flag. This is your flagship – complete failure.

    Own it’s yours. Wait, no, it’s not even yours, it belongs to the bankers.

  • Aerospike

    SLS just doesn’t make sense. It never did and once Falcon 9 Heavy has flown successfully, I hope a lot more people will realize this.

    The argument of the supporters, that SLS will be a case of “build it and they will come” is a fallacy. Unless you want to launch big things in one piece, it doesn’t provide any capability that could not be replicated by multiple, cheaper and ultimately even safer smaller launches.

    Outer planet exploration done fast? Launch your spacecraft into LEO, park it there (it has to survive for years in space anyway!), launch an ATV like transfer stage separately, dock with the probe and off you go!
    No need for SLS.

  • dr

    I seem to recall that the “increase flight rate to drop unit costs” argument was used with the space shuttle. That vehicle still ended up quite expensive on a per launch basis.
    The unfortunate situation is that you have to build a vehicle that is cheap at whatever launch rate is currently sustainable by the market. Then that low cost can catalyse an increased flight rate.
    For example, Spacex can sell about ten launches per year for their F9 rocket, which is medium lift. So they need to use reusability to bring down the per flight price of F9 to around $10m – $20m whilst flying around ten launches per year, and that will then create many more launch opportunities for F9. The resulting increase in launch opportunities will create production economies of scale that will further reduce the price.
    Claiming that you should increase the demand (flight rate) to reduce the price is putting the cart before the horse. You need to reduce the price to increase the demand (flight rate).
    (I think that for Spacex to bring the price of an F9 launch down to around $10m – $20m, they will need to make the first stage reusable about five or more times. The second stage can remain expendable to achieve this price.)

  • Michael Vaicaitis

    Elon has said that F9v1.1 can “go to an even lower price than F9v1”. So, we can only speculate as to what their actual costs are and how flight rate might, or might not, give them more flexibility on price.

    That said, he has also stated that the first stage is “about 3/4 of the cost”. Again we can only speculate upon the precise meaning of “about”. However, given as a general assumption that the first stage is exactly 0.75 of the price (and that’s price not cost, as price also includes R&D, etc..), then the cost of the second stage is a little over $14million. Pushing the assumption wagon a bit further down the road, we could say, for the sake of argument, that the fixed and operational costs sans first stage are $15,000,000. Using this as the per launch fixed cost and spreading the capital cost of the first stage over multiple launches, we get:
    4 uses of 1st stage = $25.375m per launch
    5 launches gets under $25million at $23.3m
    9 launches gets under $20million at $19.6m
    (Yes, I am a geek with a spreadsheet)
    I will also point out that the pricing of FH casts some doubt and confusion over the above assumptions.
    Also, at only 10 launches per year, the factory is only making one first stage and 10 second stages per year (plus whatever FH requires), so they will need many more launches to keep the economies of scale, but if prices are lower…..

  • Hug Doug

    well, we all know that the successful recovery and re-use of a Falcon 9 first stage will shake the space launch industry to its core. everyone who right now merely looks nervous will have to panic, and realize that SpaceX will have a lock on the medium-heavy lift market for 10 years while everyone else plays catch-up to develop their own reusable stages. and by then, they might have perfected a reusable 2nd stage, and that will drop their price even further.

    the numbers have been crunched before, but i think your analysis is probably realistic. Musk has said in the past that he wants a hundred-fold reduction in launch costs, a more conservative ten-fold reduction with a fully reusable Falcon 9 is likely, and currently a Falcon 9 launch runs around 60 million, so the eventual expectation is for a price tag of 6 million per Falcon 9 launch, depending on how many times the stages can be reused / how much it costs to refurbish and prep them.

  • Chris Courtois

    SLS… oink oink oink. That is all.

  • Michael Vaicaitis

    Musk’s comment of a hundred-fold reduction are probably referenced to ULA or Ariane. So lets be generous and say $100m for 10tonnes to LEO, $10,000/kg (the Shuttle was $60,000/kg).

    A fully reusable F9 with a capital cost of $56.5m (Of course, cores may last longer than engines, so capital cost could potentially be spread further with engine refurb.) and an operational cost of $1m (wild ass guess) could hit $5m per launch with 14 reuses – that’s $500/kg, FH might be 1/3 or 1/4 or that. So FH lifting 30-40tonnes and fully reused 15 times could be getting close to, or breaking, $100/kg.
    The trick/hope is to get to a time when the world is launching to LEO 10 or 100 times a day.

  • DaIllogicalVulkan

    Yes, yes, it makes perfect logical sense, the future of the industry could be easily defined in a statement less than a paragraph long, however I just cant seem to grasp why doesn’t something like this (“embrace international cooperation..”) does not go into effect?

  • delphinus100

    “Outer planet exploration done fast? Launch your spacecraft into LEO,
    park it there (it has to survive for years in space anyway!), launch an
    ATV like transfer stage separately, dock with the probe and off you go!
    No need for SLS.”

    I’ve said similar things about Orion. If you really *must* have it, launch on Delta IV Heavy, refuel upper stage and/or dock with separately launched (also on existing hardware) transfer stage to go deeper into space. For anyone who thinks that’s too radical, I have two words: Gemini-Agena.

    It’s been done. This architecture once took US crews record distances from Earth (max about 850 miles…somewhat more was possible, but this was already approaching the inner VanAllen belt) that stood until Apollo 8…

    And still no need for SLS.

  • DaIllogicalVulkan

    Yes, very true, for some of us this type of industry growth cant come fast enough. However on the market-side of things, how will SpaceX market cheaper launch prices in an industry in wich launch costs are not the biggest concern? While 60 million would be relatively “regular” price for satellite operators, and 6 million would be a bonanza for transport-sensitive firms such as SpaceAdventures, and Bigelow, how would SpaceX get form 60-6 when their trumpcart is “cheap prices” when customers ($59-39milion) dont care?
    I know they will definetly have the upper hand once they reach the $6mil price, but how will they sway customers to use their reusable system, in contrast to the veteran ULA disposable system?

  • Robert Gishubl

    Why use SLS at all when Falcon Heavy has nearly the same lift at a fraction of the cost. No one will pay the stupendusly high price for SLS when they have the option of Falcon Heavy, unless it is mandated by government for the purposes of pork.
    In addition once FH is flying and re-usable SpaceX will probably work on a bigger booster and as that will be based on cheaper launch costs once it is built there will be missions for it. Building something more expensive like SLS will not attract customers just because it exists as it is too expensive to consider. As launch prices drop there will be more uses for space so more missions will launch.
    Sone future set of missions will be asteroid mining and in space manufacturing that will occur once mission costs are sufficiently low. For example if an exploration mission to analysi and confirm suitability for capture and mining could be done for $100 million that is comparable with the cost of a deep water oil exploration well.
    If the cost of finding, capturing and setting up mining of an asteroid could be done for $10billion that is comparable with setting up a new (large) mine on earth.

  • DaIllogicalVulkan

    This is ridiculous*, is it me, or is everyone (Governments) gone crazy for Heavy Launchers? Seriously, Russia; making a HLV and PTKNP where they have a perfectly good Soyuz, ESA; making a bigger Ariane 6, China; a large paper-rocket when the Long March is till new, and the Ukraine; who can just barely afford a medium launch system (Cyclone) with HLV project Mayak!
    The only nation that has made a logical development step in their space program is Japan, by commercializing their medium(small) Epsilon launch system.
    *not solid argumentation material

  • DaIllogicalVulkan

    Now the argument behind the SLS is not really about “launch capabilities” or “markets” or whatever, we all know its about the firms, and the contracts, and jobs. However, couldn’t this little chasm be resolved if the government could liquidate all of the assets/capital goods going towards SLS, and transfer all(most) jobs and capital goods towards private companies, and compensate for the “added weight” with a large production order (say 150 DeltaIV’s)? It should make the politicians happy b/c everyone in their districts has a job, It should make Boeing/Astrium happy, because they no longer have to deal with excess hardware laying around, and it should make prive launch providers very happy with new equipment and a labor force and a long-term project to accompany it.
    So in economic terms it could make sense, and for people who support Zubrin’s Mars Direct plan (who coincidentally also support SLS) Cant the Mars Direct plan be down-sized to make it fit in the launch fairings of private launchers?
    if so then Zubrin’s optimistic Mars predictions might actually look more and more viable.
    Yet the question remains, why not?

  • Hug Doug

    I’m not sure I understand your question of “how will they sway customers?”… SpaceX is swaying customers with their low prices right now – $60 million is already far cheaper than the ULA or anyone else (the average ULA launch costs nearly $500 million, and an EELV launch averages $220 million), their launch manifest is evidence of that, they are booked solid through 2018, with 40 launches on their “to-do” list. it’s already a major chunk of the launch market, and it will only grow if they can prove themselves to be reliable.

    Launch costs aren’t the “biggest concern” for major companies – if you’re building a 200+ million dollar satellite, you can probably afford a 200+ million dollar launch, but why would you not want to save 150 million? – however, for smaller companies, start-ups with less capital to play around with, SpaceX will be snapping up that entire new launch market, no other launch provider will have a chance.

  • Hug Doug

    part of the reason why ULA launch costs have risen so high in the past few years is because the U.S. government bought EELV cores (there’s currently a standing order for 5 cores per year through 2018) without having much of anything to launch on them. ordering 150 more EELV cores without anything to launch on them will be expensive as hell and most of those cores would just rack up storage / refurbishment costs as the years go on.

  • therealdmt

    Robert, I don’t want the SLS — because of its immense development costs, it’s both taking away our NASA-based exploration efforts and threatening to kill our nascent private space launch industry. But IF congress forces NASA to finish the rocket, it would in fact give us a unique capability. A capability we couldn’t afford to use, but a powerful capability nonetheless. If we really, truly embraced international cooperation, the SLS could be part of new international efforts that would go quite a bit beyond Apollo.

    But what I _really_ hope is that by 2015 SpaceX will have successfully demonstrated the aborts and a manned demo flight for Dragon, a demo flight of the Falcon Heavy, and at least one successful first stage return to a land landing of a Falcon 9R first stage (and maybe a landing [on land] of the dragon capsule). At this point, given no significant failures, I think the better way would have been demonstrated, all before the first SLS test flight, and the SLS would have to be canceled (and so finally freeing up money to invest in things besides the launch vehicle).

  • dr

    So long as their reusable system is reliable, then people will use it. Its important to remember that once the price to LEO starts to drop dramatically, and Bigelow launch Alpha, that whilst Spacex can perform repetitive resupplies of Alpha, many new industries will be enabled upon Alpha. So the cargo contents of Dragon would change as different customers signed up to do different things on Alpha as the price of performing work on Alpha fell. (The price of doing just about anything on Alpha is hugely connected to the cost of launch to LEO) So one customer may want to grow protein crystals to enable the understanding of the protein structures. Another may want to perform plant growth studies as part of DNA research. Another may wish to look at monocrystalline alloy manufacture by making samples in zero-g. Another customer may want to develop hotel equipment in zero-g. Another customer may wish to study the cost and rate of diamond growth in zero-g to understand if artificial diamond prices can be reduced to enable a wider variety of industrial applications.
    So it isn’t solely about satellite launch, particularly once there is a commercial space station.
    As an analogy, in the early days of the motor industry cars were built to customer specifications by the motor companies. Volumes were very limited. Mr Ford came along with the Model T and offered it in any colour, so long as you chose black. Because he had volume and low cost, therefore price, his cars sold well. This was despite the fact that his customer base would not have been solely the super rich who had been the overwheliming majority of car buyers prior to the Model T.

  • dr

    Michael, when Elon talked about a one hundred fold reduction in price, he is talking about Falcon 9. It was based on the simple argument that F9 fuel costs something like $400k. Consequently, he argued that if reusability became infinite, then the price would tend to the cost of fuel, around 150 times cheaper than an F9 V1.0 flight. Its a simple arugment, and its not meant as a commitment, he is just trying to show that transformative pricing in space access, is theoretically possible, even if it is quite a long way from today’s pricing and technology.
    BTW your spreadsheet got five times reusability for the first stage as $23.3m, I get just a touch under $20m.

  • dr

    Heavy launchers create lots of jobs.

  • Aerospike

    Uhm, some corrections needed:
    Russias Soyuz may be “perfectly good” in your view, but I don’t think everyone will agree.

    ESA’s planned Ariane 6 is going to be _smaller_ than Ariane 5!
    (And ESA/Arianespace’s small VEGA rocket is comparable to Japan’s Epsilon!)

  • Michael Vaicaitis

    Perhaps he was talking about F9 as a reference and perhaps he was also taking a jab at the established players. Regardless, I take all your points and I fully understand the principle and Musk’s intention. Most people, including those in the space industry (perhaps *especially* those in the space industry) seem to believe that launching to space HAS to be expensive as a matter of intrinsic fact. I have also read comments on other sites, where some people have been under the impression that the fuel is upwards of 25% of the launch cost. Musk’s focus on fuel cost was no doubt aimed at this misapprehension. I suspect, that in reality, other ongoing operational costs will exceed the fuel cost.
    I realise the hundred-fold cost reduction is some vague orders of magnitude ballpark figure. However, my previous post was designed to show that a fully reusable F9/FH system could at least beat ULA et al by 100x. And, a fully reusable FH used 20 times, could be in the region of 400 times cheaper than the Shuttle and 200 times cheaper than SLS, in $/kg to orbit.

    I think the fuel cost might be lower than 400K, but then there’s assembly/re-assembly, range costs, maintenance and refurb. Anyhow, it’s difficult to see the operational costs get much below $1million. 1/4 of $56,500,000 is $14,125,000 + $1m, then round down to a guestimate of $15m.
    Check your calcs:
    First flight price = $56,500,000
    2nd stage + operational costs guesimated at $15,000,000

    gives: 4 flights x $15,000,000 = $60,000,000
    $116,500,000 / 5 flights = $23,300,000 per flight

  • dr

    $20m, $23m, frankly I’m not too fussed. They are approximations anyway.
    The key takeaway from this discussion is that “you only need a small amount of reusability to make the launch price collapse”.
    I have heard people talking about “airplane style reusability” and claiming that this will reduce launch prices. A Boeing 747 is reusable about 30,000 times. Its true that very high levels of reusability would result in cheap launch costs, but what you have shown is that something like 60% of launch cost can be eliminated with just five times reusability of the first stage. That’s still with an expendable second stage.
    As the reusability rises, the price falls, and the launch rate should grow as the number of customers increases. This gives economies of scale gains on the cost of both the second stage, despite the fact it is still disposable, and also on the overhead costs. I believe that these gains will further significantly reduce the launch price.

  • DougSpace

    SLS has unique capabilities which Falcon Heavy does not have.  For example, if you wanted to send cargo  and crew to an international lunar base, here’s approximately what the different launchers could do:
      – FH (53 mT) – 3,130 kg
      – SLS (70 mT) – 7,262 kg
      – SLS (90 mT) – 12,122 kg
    So, even though the SLS delivers only 30% more to LEO, it delivers more than double the payload to the lunar surface.  I suppose the fixed mass of the orbital transfer and landing craft is what causes the difference.

    However, if that lunar base were to produce propellant, and send it to LEO, then this changes everything.  At that point, Falcon Heavy is overkill.  A medium heavy launcher would be more than sufficient to loft a dry craft and cargo.

    Likewise, an architecture of Earth-supplied depots or even just the cheaper launch of fuel for a docking and top-off would change the size of the launchers needed.

  • DougSpace

    Regarding the relative inelasticity of the satellite market, it is true.  But there comes a point where passengers become the payload and, if you get the ticket price low enough then you begin tapping into this endless “payload” market.

    By my eyeballing / extrapolating of the following graph (Figure 7), it seems to me that at about $2,000,000 per ticket is when you get about 50 passengers per year which is about 7 launches per year which is where I think that mass production begins bringing down the production costs thereby initiating a virtuous cycle.

    http://www.spacefuture.com/archive/prospects_of_space_tourism.shtml

    2 million / ticket comes to $14 million per launch.  So, a reusable Falcon first stage gets us close.  But there’s also the Bigelow price.  But perhaps a combination of initial sovereign clients and a somewhat expanded satellite launch market and perhaps a somewhat consolidated market towards SpaceX would begin to give it enough launches to break through that $2 million per ticket price.

  • dr

    Please note that your price of $14m is in the range $10m – $20m that Michael Vaicaitis and myself were talking about further up this discussion. I believe that several different business models close once the price of launch falls below $20m for a medium life rocket, and that causes the launch market to become price elastic. Once that happens, there is no looking back. Newspace will be hit by a wave of “hot” investment money looking to develop all sorts of new products and services, and some of these will be successful. This will create an agressive virtuous circle, as you mention, that takes humanity across the inner solar system.
    BTW I reckon that the first orbital commercial space tourists will be happy with day trips. (I know that the Space adventures tourists have visited ISS for a week). So you go into space, float around, take some pictures, watch an orbital sunrise and sunset, have a meal (or two) do a few orbits, and then come back down. I don’t think that luxury space hotels will be needed initially at this ~$2m price tag. Obviously, with time, price will fall and the specifications of the experience will rise.

  • Michael Vaicaitis

    If we give SLS maximum advantage by selecting the Block II 130,000kg to LEO version. Current estimates put the launch cost of SLS at $4billion, although that may increase. $4,000,000,000 / 130,000 = $30,770/kg.

    The current prices listed by SpaceX are $135million for greater than 6.4ton to GTO or 53,000kg to LEO, or $77.1 for up to 6.4ton to GTO or 45,360kg to LEO. So for $4billion, you get between 29 launches of 53,000kg and 51 launches of 45,360kg. Thats:
    29×53000 = 1,537,000kg @ $2,600/kg, = 11.8 x SLS-130 and 22 x SLS-70
    or
    51×45360 = 2,313,360kg @ $1,730/kg = 17.8 x SLS-130 land 33 x SLS-70

    The cold hard financial reality is that Falcon Heavy is between 11.8 and 33 times more capable of delivery payload to LEO. FH has a unique capability that SLS does not have – it is affordable.

    By the way, where did you get those payload to lunar surface numbers?.

    So build a lunar base, deliver mining equipment, fuel manufacturing equipment, solar or nuclear energy to power all the above. Then locate the water, mine the water and process it into LOX and LH2. Construct landing and launch facilities on the lunar surface for lifting the processed fuel to LEO. Even if you had a spare half a trillion of finance before the first deliveries of fuel started and 50 to 100 years of patience to develop this capability, chances are the cost of lunar fuel to LEO will struggle to be competitive with fuel lifted from Earth using reusable launchers. The Moon is not a stepping stone to the solar system.

  • Robert Gishubl

    The big thing that will happen is that more companies will fly cheaper satelites. If it costs $100 mill to launch a satelite you do not send a $10 mill satelite with mass producted parts and potential single faulure modes. However if Launch cost is only $6 mill you look at the economies of mass production and build a constelation of smaller cheaper satelites with better overall coverage keeping a couple of in space or on ground spares which you launch when on orbit capability is reduced. With re-usable cheap launches there will be more capability for quick reaction launches to launch on ground spares.
    WIth high launch costs there is not much incentive to reduce satelite cost too much but with cheaper launch costs there will be more pressure to offer cheaper satelites.

  • Robert Gishubl

    No need to wait for Luna fuel, just send it to LEO on a seperate FH launch either as a seperate propulsion-service module to dock to in orbit or to fill up a fuel depot. The fuel depot could then fuel permanent re-usable space tugs for the luna transfer. A lot cheaper than SLS and you could do it a lot sooner too. The cost of developing a transluna stage capable of docking with a luna cargo module would be trivial compared to what is being spent on SLS.
    You then just limit individual components to 53 or 45 mT depending on ecconomics and assemble in space. It is not practical to launch an entire base from earth and land it on the moon in one go so any base needs to be assembled on site. So individual modules of 70 or 53 mT makes little difference when the launch cost difference is so huge. If SLS was in the ball park of disposable FH you may have some justification but SLS is not and FH costs will come down with reusability making SLS even more of a waste than it is now.

  • DaIllogicalVulkan

    Ariane6*
    oh right right my bad,
    slipped my mind
    But, wouldn’t it be easier to just refurbish a Soyuz for (for deep space or whatever) than building an entirely new ship form scratch* and hasnt it flown for 35 years or so?

    *they’ve worked on designs for a while now but still im refering to the new factors of production, engines ect.

  • DaIllogicalVulkan

    Yes, that is very true, but wouldn’t it be easier to just to give large production orders to private launchers (ULA/Ariane)? In order to fill this big government delivery order (moon/mars/asteroid/whatever), businesess will be prompted hire more workers, and invest in more capital goods.

  • dr

    Many small launchers of the same design allows for automation. ie. not many jobs. A few large launchers doesn’t justify much automation, so far more people can be employed. To maximise employment, its best to make all the large launchers to a slightly different design, so that extensive testing has to be repeated and most production line components have to be changed.
    The risk with ordering many small launchers is that you risk your money being turned into mainly profits and only a small amount of that money being used to employ people.
    You need to think about how to maximise the pork.
    In other words, to create the most jobs, they should develop SLS, build it, fly it once, then scrap it, and then start developing an SLS 2. They could have a flight rate of one flight per every 15 years and a cost per flight of anywhere between $30bn – $50bn.

  • DougSpace

    > FH has a unique capability that SLS does not have – it is affordable.

    How very true. However, what I was specifically referring to was how much could be launched to the lunar surface with a single launch. Small increments in kg to LEO make a big difference in terms of kg to the lunar surface. And, I believe that the mass of a single Mission to the lunar surface is important because it determines how soon one can deliver the complete set of equipment necessary to go from ice to propellant hence initiating cis-lunar transportation services.  That “how soon” issue significantly influences investors’ decision whether to invest or not (even in a public-private program).

    However, I should have added to my list how much kg to the lunar surface a couple of FH launches, docked in LEO would give. I don’t have those numbers in front of me but you can consider that two FHs would give a total of 106 tonnes at LEO (but with a larger percent of that being structure) resulting in something like 15 tonnes on the lunar surface.

    > By the way, where did you get those payload to lunar surface numbers?

    I did my own calculations. Any double checking to confirm would be appreciated.  I assumed LH/LOX isp=453, (I believe) 12% (or maybe it was 15%) dry mass, and a path in which a LOX tank was left at L1.

    > the first deliveries of fuel started and 50 to 100 years of patience to develop this capability

    Michael, I’d like to encourage your thoughtful reconsideration of this perspective. Please think about it. The LCROSS mission demonstrated that at least 6% of the icy regolith is water ice. There is even some suggestion that, at the lunar north pole the ice is in the form of pure slabs. So, what mass of equipment would be necessary to harvest (excavate vs in situ melt depending upon prospecting data) that ice, perhaps steam it out of the regolith, distill it, and then electrolyze it? Storage tanks are not necessary because, initially, the lander’s fuel tanks can serve as storage.  I believe one doesn’t need 50-100 years.  Rather, I believe that that amount of equipment, spares, and a dexterous telerobot could be delivered in a single launch within the fairing of either an SLS or FH.  If the system isn’t able to harvest enough propellant to refuel for a complete cis-lunar circuit (water or propellant deliveries to LEO) then follow-on missions would build up the equipment and even humans sent on the same landers should be able to get the system working sufficiently to fuel cis-lunar circuits.  50 years is way more time than what’s needed.

    > A spare half trillion

    That much money could purchase nearly 4,000 Falcon Heavy launches or put another way, that amount of money would purchase the equivalent of the development of a bit over 1,000 Falcon 9s.  Let’s be reasonable here.  We’re talking about the technology needed to go from lunar ice to propellant to bringing it to LEO.  This is doable on a reasonable budget.

  • Jack

    The SLS allows everything to be launched in as few payloads as possible reducing the number of launches for a trip into deep space. That’s why they launched everything at once in the apollo missions using the Saturn 5. Also the SLS will take us to asteroids that we can mine for billions of dollars in resources. Also would you rather have a space shuttle that costs $450 million per launch just to take astronauts to a space station or would you rather finally start exploring deep space for $50 million more? Ether way nasa has the money. Their annual budget is about 1.7 billion and the SLS is $500 million. So they would still have a huge amount of money for other things.

  • Aerospike

    Fewer launches is a bad thing, not an advantage! Not only does in increase costs per launch, it also automatically leads to a rocket that is less safe (simply because it isn’t well known, the (ground) crews get less experience). And as stated by many others: with SLS you do not have the money to develop those big payloads you are talking about.

    You can go mine asteroids with any commercial (medium/heavy) launcher that is currently available.

  • Gath Gealaich

    “ESA’s planned Ariane 6 is going to be _smaller_ than Ariane 5!”

    Uhm…nope? http://www.spacelaunchreport.com/ar6side.jpg

  • Aerospike

    If you check the date of my comment you will realize that it was written a long time before the current “final” design of Ariane 62 and 64 has been made public. Therefore I was referring to the all solid proposal, named P7C Design in your graphic, which was supposed to be not only physically smaller, but would have had only about half the lift capacity of Ariane 5 ECA…

  • Jack

    I would be more behind SLS/Orion if it had more of a legitimate mandate behind it like how the Saturn 5 was meant for the moon landings but right now NASA’s Jorney to Mars is a pipe dream without proper funding & a lack of public intrest. NASA would have been far better off funding the commercial crew program better while the ISS is still in operation until 2028 then focus on crewed deep space missions. If the ISS was retired & NASA had literally nothing else to do in terms of human spaceflight then SLS/Orion would make more sense.

    Congress really should have waited & continued to support SpaceX more. If they did that instead of blowing billions of dollars on SLS/Orion, SpaceX could have had the ITS (interplanetary transport system) ready by the time the ISS is retired & NASA could just use ITS for a few crewed science trips to Mars & at a fraction of what it would cost to use the SLS.