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posted by janrinok on Wednesday March 28 2018, @08:08PM   Printer-friendly
from the weighty-problem dept.

NASA chief explains why agency won't buy a bunch of Falcon Heavy rockets

Since the launch of the Falcon Heavy rocket in February, NASA has faced some uncomfortable questions about the affordability of its own Space Launch System rocket. By some estimates, NASA could afford 17 to 27 Falcon Heavy launches a year for what it is paying annually to develop the SLS rocket, which won't fly before 2020. Even President Trump has mused about the high costs of NASA's rocket. On Monday, during a committee meeting of NASA's Advisory Council, former Space Shuttle Program Manager Wayne Hale raised this issue. Following a presentation by Bill Gerstenmaier, chief of human spaceflight for NASA, Hale asked whether the space agency wouldn't be better off going with the cheaper commercial rocket.

[...] In response, Gerstenmaier pointed Hale and other members of the advisory committee—composed of external aerospace experts who provide non-binding advice to the space agency—to a chart he had shown earlier in the presentation. This chart showed the payload capacity of the Space Launch System in various configurations in terms of mass sent to the Moon. "It's a lot smaller than any of those," Gerstenmaier said, referring to the Falcon Heavy's payload capacity to TLI, or "trans-lunar injection," which effectively means the amount of mass that can be broken out of low-Earth orbit and sent into a lunar trajectory. In the chart, the SLS Block 1 rocket has a TLI capacity of 26 metric tons. (The chart also contains the more advanced Block 2 version of the SLS, with a capacity of 45 tons. However, this rocket is at least a decade away, and it will require billions of dollars more to design and develop.)

SpaceX's Falcon Heavy TLI capacity is unknown, but estimated to be somewhere between 18 and 22 tons (between the known payloads of 16.8 tons to Mars and 26.7 tons to geostationary orbit).

Does the SLS need to launch more than 18 tons to TLI? No. All of the currently planned components of the Lunar Orbital Platform-Gateway (formerly the Deep Space Gateway) have a mass of 10 tons or less due to flying alongside a crewed Orion capsule rather than by themselves. Only by 2027's Exploration Mission 6 would NASA launch more massive payloads, by which time SpaceX's BFR could take 150 tons to TLI or even Mars when using in-orbit refueling.

Related: NASA Eyeing Mini Space Station in Lunar Orbit as Stepping Stone to Mars
NASA and Roscosmos Sign Joint Statement on the Development of a Lunar Space Station
President Trump Signs Space Policy Directive 1
Russia Assembles Engineering Group for Lunar Activities and the Deep Space Gateway
After the Falcon Heavy Launch, Time to Defund the Space Launch System?
President Trump Praises Falcon Heavy, Diminishes NASA's SLS Effort


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  • (Score: 3, Interesting) by khallow on Wednesday March 28 2018, @09:17PM (13 children)

    by khallow (3766) Subscriber Badge on Wednesday March 28 2018, @09:17PM (#659691) Journal

    In response, Gerstenmaier pointed Hale and other members of the advisory committee—composed of external aerospace experts who provide non-binding advice to the space agency—to a chart he had shown earlier in the presentation. This chart showed the payload capacity of the Space Launch System in various configurations in terms of mass sent to the Moon. "It's a lot smaller than any of those," Gerstenmaier said, referring to the Falcon Heavy's payload capacity to TLI, or "trans-lunar injection," which effectively means the amount of mass that can be broken out of low-Earth orbit and sent into a lunar trajectory. In the chart, the SLS Block 1 rocket has a TLI capacity of 26 metric tons. (The chart also contains the more advanced Block 2 version of the SLS, with a capacity of 45 tons. However, this rocket is at least a decade away, and it will require billions of dollars more to design and develop.)

    That's a dishonest answer as usual. Rockets don't need large TLI capacity for Lunar expeditions. Assemble the rocket in LEO (Low Earth Orbit), and then when fully assembled, fueled, tested, and loaded, send it on its way. Each launch of the reusable version of the Falcon Heavy puts 54 metric tons in orbit for around $90 million. 108 metric tons is ample for a lunar mission, sortie, settlement, or just unmanned cargo. A billion dollars per launch of the SLS, putting a mere 45 metric tons to TLI, could instead be 11 launches of the Falcon Heavy with 600 metric tons in LEO (or 200 metric tons in TLI, for what that's worth). And once you have something in LEO, you can accelerate with engines a lot more efficient than chemical engines. Solar-electric propulsion could put the great majority of that 600 metric tons in LLO (Low Lunar Orbit), but would have to be unmanned (repeated passes through the Van Allen belts).

    My view is the following. Develop multiple standard vehicle chassis for manned and unmanned flights. The Falcon Heavy is apparently intended for unmanned work so use it strictly for that with manned flights from Earth going up on either the Falcon 9, Atlas V Heavy, or even the Ariane 6.

    Let's suppose for starters that one does a standard one-size-fits-all approach. Two Falcon Heavy launches to bring up rocket stages and propellant and a Falcon 9 launch to bring up a Dragon capsule (which wouldn't be launched until the rest of the vehicle has been checked for safety problems). Because passage through the Van Allen belts needs to be quick for passengers, right there we're stuck in the near future with chemical propulsion. 108 tons would cover acceleration to TLI, then in three days deceleration to LLO. The lunar landing stage could either come up with the manned Dragon capsule or with the other two payloads. Thus, for the cost of gear and somewhere around 200-250 million in launch costs, we can put six people and a fair bit of payload on the Moon with the SpaceX family.

    Unmanned in this light would be about the same. However, as I noted above, if one is willing to take longer, say six months, one could send a lot of radiation insensitive gear and materials via solar-electric propulsion to LLO with most of the payload making it to LLO (maybe 60-80 metric tons at the end). It would even be possible to reuse the solar-electric system for further trips to the Moon, though obviously the vehicle would take some time to return to LEO and you would lose some of your payload mass.

    But instead, NASA is insisting on the Apollo approach despite it not making sense from either a safety or economic standpoint. The reason is painfully obvious. Because that approach requires the SLS's unusual capabilities. Specifying capabilities that rule out cheaper, more sensible approaches is a common US government tactic, not only used by NASA.

    Consider this. Suppose you want to deliver a 50 pound cost from point A to point B on a continent. Ok, all you need to do is pay a shipper and it's there in a few days.

    Now, let's add on the totally innocuous requirement that it needs to travel by road. Shipper can still do that and the rate probably won't change. Now, let's add on the requirement that the box can't be traveling any slower than 200 MPH. Oops, now we're talking relay teams of super cars. Adding requirements massively increased the cost by many orders of magnitude.

    This is the game. Keep adding requirements to the task, until only your desired solution can handle them. NASA doesn't need to throw 45 metric tons to TLI in one go, but by doing so, they rule out the far cheaper Falcon Heavy in favor of the SLS.

    This is precisely the sort of crap that NASA shouldn't be doing in the first place. It shouldn't be a willing enabler of a really bad and dangerous system when there's far better at hand.

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  • (Score: 0) by Anonymous Coward on Wednesday March 28 2018, @09:19PM

    by Anonymous Coward on Wednesday March 28 2018, @09:19PM (#659692)

    SpaceX and each of its engineers will be forced at the point of a gun to fund a competing launch vehicle. It's insane. It's anti-American (in philosophy, not history). It's anti-Capitalism.

  • (Score: 2) by bob_super on Wednesday March 28 2018, @09:41PM (3 children)

    by bob_super (1357) on Wednesday March 28 2018, @09:41PM (#659701)

    As someone pointed out in the ARS comments: Can't use FH, because the lunar pieces are designed to be launched on SLS, because SLS needs the lunar pieces to be designed to be launched on SLS, and NASA needs the SLS to be funded for the rest of NASA to be funded.

    Would it save money to launch multiple pieces on FH ? Apparently yes, but let's spend half a dozen years studying the changes required first, while we spend billions per year building the SLS and all the other pieces. Then we can all agree that the other way would have been cheaper, but since we already have those things almost (yet never quite) ready for the moon, it's that, or wait another 20 years, or learn Chinese...
    What? It would still be cheaper with FH and 5 years of delays, then with billion-per-launch SLS? Look, dude ... Wait, where are you building those engines, again?

    • (Score: 0) by Anonymous Coward on Wednesday March 28 2018, @09:47PM (2 children)

      by Anonymous Coward on Wednesday March 28 2018, @09:47PM (#659702)

      Get the government out of Space Exploration.

      • (Score: 0) by Anonymous Coward on Wednesday March 28 2018, @11:09PM (1 child)

        by Anonymous Coward on Wednesday March 28 2018, @11:09PM (#659743)

        Why? What is your problem? Deep State for Deep Space, I always say!

        • (Score: 2) by bob_super on Thursday March 29 2018, @04:37PM

          by bob_super (1357) on Thursday March 29 2018, @04:37PM (#660034)

          Probably the AC who will explain that only by individual humans having mutual agreed contracts with the aliens, likely enforced by Vogons, will we be able to happily colonize the galaxy.

  • (Score: 1) by tftp on Wednesday March 28 2018, @10:10PM (2 children)

    by tftp (806) on Wednesday March 28 2018, @10:10PM (#659716) Homepage
    Is FH certified to fly humans?
    • (Score: 2) by takyon on Wednesday March 28 2018, @10:19PM

      by takyon (881) <{takyon} {at} {soylentnews.org}> on Wednesday March 28 2018, @10:19PM (#659721) Journal

      It doesn't need to be. F9 and BFR will be used instead. F9 will get certified before SLS flies even once.

      The SLS strategy of flying cargo and crew on the same Lunar Orbital Platform-Gateway missions is a consequence of the effective $3 billion per launch cost, and the political desire to get some degree of manned spaceflight using the SLS in the short term.

      --
      [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
    • (Score: 2, Informative) by khallow on Wednesday March 28 2018, @11:43PM

      by khallow (3766) Subscriber Badge on Wednesday March 28 2018, @11:43PM (#659763) Journal
      It isn't. I recall hearing Musk say that FH wouldn't fly manned unless SpaceX can't get the BFR to work.
  • (Score: 0) by Anonymous Coward on Thursday March 29 2018, @06:06PM (1 child)

    by Anonymous Coward on Thursday March 29 2018, @06:06PM (#660105)

    Do do they already assemble, fuel, test, and launch vehicles from LEO, or are you purposefully burying the NRE for that and hand-waiving it away? What kind of platform do you need to "just do" all this wonderful stuff you just mentioned? A second space station, maybe, or one a whole lot bigger? You're using the exact argument the SLS is using: once this is developed, built and in use, you'll save a lot of money.

    • (Score: 2, Informative) by khallow on Thursday March 29 2018, @07:37PM

      by khallow (3766) Subscriber Badge on Thursday March 29 2018, @07:37PM (#660157) Journal

      Do do they already assemble, fuel, test, and launch vehicles from LEO

      Yes. For example, the International Space Station has done all that though much of it at a much smaller scale than would be done with the Falcon Heavy. While we would need to prove the appropriate infrastructure (which probably would involve cryogenic storage which is less, once it's done, it's done. It's a one-time risk that is retired once you've done it.

      And the level of assembly needed is very crude - at the level of Apollo which has done a couple dozen successful docking maneuvers in TLI and LLO.

      Meanwhile the enhanced risks and cost of SLS happen every mission. You can't retire them. They never go away because they never launch the SLS vehicles often enough to do so.

  • (Score: 2) by turgid on Thursday March 29 2018, @08:50PM (2 children)

    by turgid (4318) Subscriber Badge on Thursday March 29 2018, @08:50PM (#660187) Journal

    That's a dishonest answer as usual. Rockets don't need large TLI capacity for Lunar expeditions. Assemble the rocket in LEO (Low Earth Orbit), and then when fully assembled, fueled, tested, and loaded, send it on its way.

    And do you want to go to the Moon in 5 years or 25 years? When was the last time anyone had the technology (developed, tested, reliable) to assemble large rockets in orbit?

    Everything's easy when you're a bean counter.

    • (Score: 1) by khallow on Thursday March 29 2018, @09:25PM

      by khallow (3766) Subscriber Badge on Thursday March 29 2018, @09:25PM (#660207) Journal

      And do you want to go to the Moon in 5 years or 25 years?

      Falcon Heavy flies right now. SLS may never fly.

    • (Score: 1) by khallow on Thursday March 29 2018, @09:39PM

      by khallow (3766) Subscriber Badge on Thursday March 29 2018, @09:39PM (#660213) Journal
      I'll also note that we could have already had a lunar presence, if we had done such assembly with the variety of 20-25 metric ton rockets available to us around the world. It'd be more work, but it's something we could have started in 1970 rather than 2022.

      I think that bears repeating. We could have had several SpaceXs created in 1970 instead of 2002. All that crazy space stuff could be done by now rather than still being some indefinite 5 years, 25 years, or maybe longer in our future.

      My view is that there is no manned lunar program because it's not going to survive the funding drain from SLS. Kill SLS, stake through the heart, then we have money to work with.