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posted by martyb on Tuesday March 12 2019, @02:07AM   Printer-friendly
from the Merlin,-Falcon-9,-and-Falcon-Heavy-were-developed-for-less-than-$1B-total dept.

NASA budget proposal targets SLS (Space Launch System)

The White House's fiscal year 2020 budget request for NASA proposes to delay work on an upgraded version of the Space Launch System and would transfer some of that vehicle's payloads to other rockets.

The proposal, released by the Office of Management and Budget March 11, offers a total of $21 billion for the space agency, a decrease of $500 million over what Congress appropriated in the final fiscal year 2019 spending bill signed into law Feb. 15.

A major element of the proposal is to defer work on the Block 1B version of the SLS, which would increase the rocket's performance by replacing its existing Interim Cryogenic Propulsion Stage with the more powerful Exploration Upper Stage. The budget "instead focuses the program on the completion of the initial version of the SLS and supporting a reliable SLS and Orion annual flight cadence," the OMB budget stated. The first SLS/Orion mission, without a crew, is now planned for the "early 2020s," according to the budget, an apparent slip from the planned 2020 launch of Exploration Mission 1.

NASA had previously planned to use the Block 1B version of SLS to launch elements of its lunar Gateway, using a "co-manifesting" capability enabled by the rocket's greater performance. Instead, according to the budget document, those components will be launched on "competitively procured vehicles, complementing crew transport flights on the SLS and Orion."

[...] The budget proposal would also remove one non-exploration payload from the SLS manifest. The proposal offers $600 million for the Europa Clipper mission, enabling a launch in 2023. However, NASA would instead seek to launch the mission on a commercial launch vehicle rather than SLS, a move it claims "would save over $700 million, allowing multiple new activities to be funded across the Agency." The fiscal year 2019 budget request also proposed a commercial launch of Europa Clipper, but Congress placed into law in the final funding bill the requirement to use SLS for that mission.

Are we nearing a good timeline?

Related: After the Falcon Heavy Launch, Time to Defund the Space Launch System?
House Spending Bill Offers NASA More Money Than the Agency or Administration Wanted
NASA Administrator Ponders the Fate of SLS in Interview
SpaceX's Falcon Heavy Could Launch Japanese and European Payloads to Lunar Orbital Platform-Gateway
Northrop Grumman Exec Warns of Coming "Affordability" in the Space Launch System's Future
Impact of the Midterm Elections May be Felt at NASA
When Space Science Becomes a Political Liability


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  • (Score: 2) by Immerman on Thursday March 14 2019, @06:35PM (5 children)

    by Immerman (3985) on Thursday March 14 2019, @06:35PM (#814365)

    Except that they've already committed to building a passenger Starship, and have even already sold an early flight on one. Plus it's likely a simpler vehicle than the cargo version with it's giant hinged fairing that interferes with structural symmetry. It doesn't matter how much cheaper and easier it would be to modify the Dragon 2, if they already plan to make Starship anyway. And Starship should rapidly become cheaper per-launch than a Dragon capsule anyway. And of course, if the Dragon's track record is any indication, NASA certification is the difficult part of the process, and would likely have to be repeated on a

    And it does have at least one credible and important immediate purpose: marketing footage. And let's be honest - a great deal of Musk's success has been due to his ability to manage the media image of his companies.

    Not to mention, being able to launch an entire dedicated temporary space station larger than the ISS (by pressurized volume), pre-loaded with any experiments, entertainment, etc., for less than the cost of a single Falcon 9 launch, is going to have lots of research and recreational potential. *I* probably won't be able to afford it, but plenty of others will. That kind of space even allows for dual-purpose launches: you might launch a mission to service the ISS (likely not possible for the cargo/fairing version) using 10% of the available capacity, vastly exceeding anything currently available, while using the remaining 90% of capacity for recreational space tours or independent orbital experiments. If NASA is already funding the launch, then the extra passengers are pure profit.

    Then there's the fact that he also intends this thing to be able to land on the moon and return - and an orbital cargo split fairing is unlikely to work in a substantial gravity field. Plus, it can serve just as well as a temporary lunar base as a temporary space station, which should dramatically simplify early scouting and development missions to the lunar surface.

    There's also the plan to sell ridiculously fast sub-orbital passenger flights.

    And of course, it's also vital to a longer-term purpose of getting to Mars, which seems to be the vision actually driving Musk, and thus arguably the single most important purpose of any of his rockets.

    >Every human spacecraft made today is capable of those things.

    Umm, no, they're not. From what little I can find none of the capsules you mention are capable of returning from lunar orbit under their own power. Shenzhou has never been to lunar orbit, and while Soyuz-L has it appears to have used a separate booster for the return.
    Generally speaking our space "toys" have fallen into two distinct classes: Boosters, that can impart significant delta-V, but lack the capacity for precision maneuvering, and capsules such as you mention, that can perform precision maneuvering, but can typically only deliver a the relatively small amount of delta-V to begin reentry from low Earth orbit. To service a lunar orbital station you'd need to do both.

    For reference: Getting from low Earth orbit to low lunar orbit requires about 4km/s of delta-V (assuming high thrust, low thrust doubles that), though the return only requires about 1.3km/s if you make use of atmospheric aerobraking. That's still just shy of half the 2.7km/s needed to return from the lunar surface, and a *lot* more than needed to deorbit from LEO. The space shuttle typically made a 200-550fps (61 - 168m/s) reentry burn to return from LEO, depending on altitude. So you're talking about around 10x the necessary delta-V to return from lunar orbit.

    https://en.wikipedia.org/wiki/Delta-v_budget [wikipedia.org]
    https://space.stackexchange.com/questions/12011/how-could-a-90-m-s-delta-v-be-enough-to-commit-the-space-shuttle-to-landing [stackexchange.com] (I couldn't find the specific numbers referenced in the manual)

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  • (Score: 1) by khallow on Thursday March 14 2019, @06:55PM (4 children)

    by khallow (3766) Subscriber Badge on Thursday March 14 2019, @06:55PM (#814373) Journal

    Except that they've already committed to building a passenger Starship, and have even already sold an early flight on one. Plus it's likely a simpler vehicle than the cargo version with it's giant hinged fairing that interferes with structural symmetry. It doesn't matter how much cheaper and easier it would be to modify the Dragon 2, if they already plan to make Starship anyway. And Starship should rapidly become cheaper per-launch than a Dragon capsule anyway. And of course, if the Dragon's track record is any indication, NASA certification is the difficult part of the process, and would likely have to be repeated on a

    While true, it still remains that NASA could pay for the modification to Dragon 2 on top of Starship and still pay orders of magnitude less than it would with the SLS approach. Second, with respect to NASA certification, you can be sure that the SLS won't have to (because it won't be able to) pass the same certification process.

    Not to mention, being able to launch an entire dedicated temporary space station larger than the ISS (by pressurized volume), pre-loaded with any experiments, entertainment, etc., for less than the cost of a single Falcon 9 launch, is going to have lots of research and recreational potential.

    I'll believe that when I see it. I don't buy those numbers at present. That's based on BFR having a mass fraction to LEO which I think may be impossible for a chemical propulsion system to achieve. We'll see.

    >Every human spacecraft made today is capable of those things.

    Umm, no, they're not. From what little I can find none of the capsules you mention are capable of returning from lunar orbit under their own power. Shenzhou has never been to lunar orbit, and while Soyuz-L has it appears to have used a separate booster for the return.

    Generally speaking our space "toys" have fallen into two distinct classes: Boosters, that can impart significant delta-V, but lack the capacity for precision maneuvering, and capsules such as you mention, that can perform precision maneuvering, but can typically only deliver a the relatively small amount of delta-V to begin reentry from low Earth orbit. To service a lunar orbital station you'd need to do both.

    You already outlined the division of functionality. Slap a booster on and you have the delta-v capability needed for the capsule. It's a solved problem. After all, we already have boosters (the orbital launch vehicles) that put the capsule into orbit in the first place. That's roughly 10 km/s of delta-v right there.

    • (Score: 2) by Immerman on Thursday March 14 2019, @08:45PM (3 children)

      by Immerman (3985) on Thursday March 14 2019, @08:45PM (#814446)

      >...NASA pay for...SLS...
      Sure, but why would they do that if the SpaceX Starship is already available, cheaper, and far more capable?

      > Slap a booster on
      Except it's not quite that simple - the booster will make the capsule far more cumbersome to maneuver precisely for docking. So the capsule would have to either detach from the booster for docking with the lunar orbital station, and then reconnect for the return to Earth orbit, or be modified (hardware or software) to be able to precisely maneuver despite a much greater mass and very different center of gravity.

      Either could probably be done, but both likely involve considerable engineering and testing, and probably re-certification. On a capsule that SpaceX has already removed from its roadmap, and that won't have anywhere near the capability of its replacement.

      • (Score: 1) by khallow on Thursday March 14 2019, @09:04PM (2 children)

        by khallow (3766) Subscriber Badge on Thursday March 14 2019, @09:04PM (#814464) Journal

        Sure, but why would they do that if the SpaceX Starship is already available, cheaper, and far more capable?

        Well, the Starship isn't yet already available for starters. But then again, it's a hell of a lot more available than the SLS.

        Except it's not quite that simple - the booster will make the capsule far more cumbersome to maneuver precisely for docking.

        Unless, of course, the booster isn't on the capsule at the time. You don't need to dock a capsule with fueled booster. Ever.

        So the capsule would have to either detach from the booster for docking with the lunar orbital station

        Has my vote. I doubt anyone will ever want a booster near the station.

        Either could probably be done, but both likely involve considerable engineering and testing, and probably re-certification.

        Both which are already proven features of every manned space capsule out there. That is, they've already been engineered and tested before with some booster configuration (else they wouldn't get into space in the first place), and the parties involved in the design and construction of these vehicles already have experience with testing and certification for their appropriate country's space program.

        • (Score: 2) by Immerman on Thursday March 14 2019, @09:43PM (1 child)

          by Immerman (3985) on Thursday March 14 2019, @09:43PM (#814502)

          Yes, they have experience with the testing and certification. That doesn't mean they want to go through it for something that doesn't serve their purposes. And a "Dragon 2-L" doesn't serve SpaceX's purposes.

          Now, *if* a passenger Starship isn't looking to be available by the time they start sending people to LOP-G, perhaps NASA could offer enough incentive for SpaceX to take some of their engineers away from BFR development to work on a new Dragon revision, as a stopgap solution. But I suspect that would be a hard sell if the BFR/BFS were near fruition.

          • (Score: 1) by khallow on Thursday March 14 2019, @11:04PM

            by khallow (3766) Subscriber Badge on Thursday March 14 2019, @11:04PM (#814525) Journal

            Yes, they have experience with the testing and certification. That doesn't mean they want to go through it for something that doesn't serve their purposes.

            A purpose like getting paid well by someone with deep pockets?

            My point here is not to claim that NASA will launch everything on Dragon 2s, but rather that these problems aren't particularly difficult for any party that is already putting space capsules in orbit. Going back to my original point:

            Send two Falcon Heavies then. A key problem here is that we don't need the capabilities of an SLS, but we will need orbital assembly. So might as well use the vastly more economical Falcon Heavy (and/or the BFR) and use orbital assembly which you were going to develop anyway. Or even the considerable number of 20-25 ton payload rockets currently in existence.

            The supporters for the SLS are playing the same game that was played with the Space Shuttle and Constellation. They tout the capabilities of the vehicle. But that ignores two very important things. First, that the capabilities are unnecessary. We can work around all the problems of using smaller payload vehicles with modest effort and cost, and launch today. Second, there's the matter of cost. It doesn't matter how awesome your launch vehicle is, if you can't afford to use it. In addition to the huge delays, the SLS has a very low launch frequency (slower than anything except possibly the Delta IV). That means each launch, when it happens, will be very expensive.

            That's why I'm outright against funding the SLS. It's a huge drain on NASA's resources and doesn't further any US interests. What it does do, and which may lead to it lingering around decades into the future, is distribute federal swag to the right zip codes.