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NASA, France Skeptical of SpaceX Reusable Rocket Project 333

MarkWhittington writes: "The drive by SpaceX to make the first stage of its Falcon 9 launch vehicle reusable has attracted the attention of both the media and the commercial space world. It recently tested a first stage which 'soft landed' successfully in the Atlantic Ocean. However both NASA and the French space agency CNES have cast doubt that this kind of reusability could ever be made practical, according to a Monday story in Aviation Week. SpaceX is basing its plan on the idea that its Merlin 1D engines could be reused 40 times. However, citing their own experience in trying to reuse engines, both NASA and the CNES have suggested that the technical challenges and the economics work against SpaceX being able to reuse all or part of their rockets. NASA found that it was not worth trying to reuse the space shuttle main engines after every flight without extensive refurbishment. The CNES studied reusing its Ariane 5 solid rocket boosters liquid fueled and reusable but soon scrapped the idea."
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NASA, France Skeptical of SpaceX Reusable Rocket Project

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  • NASA, France Skeptical of SpaceX Reusable Rocket Project

    Yes, that's a lovely headline. But the original headline ("NASA, CNES Warn SpaceX of Challenges in Flying Reusable Falcon 9 Rocket") tells the same story with 42% less bullshit.

    NASA found that it was not worth trying to reuse the space shuttle main engines after every flight without extensive refurbishment.

    Really? So because the space shuttle couldn't do it, nobody could do it, perhaps by learning lessons from the shuttle program? If this is an example of the kind of thinking in the article, it's a fat waste of time. If it isn't an example, why mention it at all?

    I went ahead and skimmed the article, and indeed, the sole counterexample to the potential of reuse continues to be the space shuttle. The article is crap. Flush.

  • Denying Reality (Score:5, Informative)

    by Teancum ( 67324 ) <robert_horning&netzero,net> on Wednesday May 07, 2014 @08:30AM (#46938349) Homepage Journal

    No doubt that SpaceX has put a whole lot of effort into making this work, but it amazes me that people who are otherwise knowledgeable about this kind of stuff can't stand looking at actual results rather than assuming this is just random musings. One of the ways SpaceX knows how many potential launches they can get out of their engines is because they have put some of these Merlin-1 engines on their test stand in Texas and have fired them for full mission duration burns 40-50 times. SpaceX definitely doesn't make up these numbers out of their hind end but rather from experience and actually using this equipment.

    Again reality sort of bites these guys hard because SpaceX has been able to bring the 1st stage down to a soft landing. With the most recent launch, SpaceX was denied the opportunity to do more because both the FAA and the USAF folks at Cape Canaveral didn't really want that return stage going anywhere near the launch pad until SpaceX has proven they have control of the vehicle. Regardless, SpaceX has done the really hard part of actually getting the spacecraft to return in a recoverable condition.... something these "experts" in this article are denying is even possible in a theoretical sense.

    The 2nd stage recovery is going to be a whole lot harder, and it is something that even SpaceX themselves have said may not be successful. Still, I wouldn't categorically write off SpaceX either and it is just stupid to dismiss something like this as impossible without even making an attempt to see if it could be done.

  • Re:Just because... (Score:5, Informative)

    by torkus ( 1133985 ) on Wednesday May 07, 2014 @08:43AM (#46938427)

    Exactly.

    NASA built redundancy into everything because they didn't know better. Material science was far less developed. Computer simulations basically non-existent. They didn't design a 30% margin into parts, they guessed and fixed whatever part broken with a strong/better one and tried again. If some part was 5000% over-engineered it wouldn't break but would negatively impact the overall system complexity/weight.

    I'm pretty sure NASA (and plenty of others) also said Elon/Space-X was stupid for getting into building launch vehicles too. Yet here we are with their innovation not only a success, but bringing cheaper launches than anyone else. Clearly Space-X is not to be believed. /sarcasm

  • Re:Just because... (Score:5, Informative)

    by Teancum ( 67324 ) <robert_horning&netzero,net> on Wednesday May 07, 2014 @09:02AM (#46938625) Homepage Journal

    Beyond stating the obvious, these quotes from the NASA engineers don't really seem to fly with me.

    I get that building rocket engines is a tough challenge, as can be clearly demonstrated by how few new rocket engine designs ever get completed.n All of the complaints about the RD-180 engine with its manufacturing being done in Russia center around the fact that trying to get even just a rough equivalent would require building a brand new engine from scratch. For large engines that can launch payloads of several metric tones into orbit, typically only one or two ever get designed each decade by anybody around the world. This past decade one of those engines was the Merlin engine designed by SpaceX.

    What makes the Merlin engine so interesting is precisely because it is bland. SpaceX hasn't been trying to push the envelope in a hardcore sense with exotic fuels or pushing the limits of specific impulse (the efficiency rating of a rocket engine). Instead they are using rather mundane fuels (Kerosene and Liquid Oxygen.... stuff used in rockets for decades) and instead are trying to simplify the design of the rocket every chance they get. Also unlike the SSME, the #1 consideration on building the Merlin has been saving money and not trying to improve performance.

    I'll also note that SpaceX does not intend to do sea recovery of these rockets, so doing any consideration of salt water besides general ocean spray into the launch environment (still a problem at KSC) is not really an issue. A problem facing the managers at KSC, or rather the Cape Canaveral Air Station, is trying to find a place for these stages to land. Both the Cape Canaveral Staff and the FAA-AST want to make sure that SpaceX doesn't land their rockets on top of other facilities (like taking out pad 39B), but that is a traffic control problem and not anything to do with the technical capability of getting the rockets to a recoverable location.

    As for the economics argument, a company driven by profits rather than a government agency who gets billions of dollars to extend failed programs is somebody who I expect to understand if something is going to be economically feasible or not. I'm sure SpaceX has done all of the number crunching a long time ago as they don't have the sugar daddies in the U.S. Senate to bail them out if it doesn't work.

  • by FatLittleMonkey ( 1341387 ) on Wednesday May 07, 2014 @09:47AM (#46939083)

    GP is referring to Freedom Space Station, not Skylab. You know that, why are you lying and pretending you don't?

    Freedom was proposed to Reagan in '86 and accepted in '88 (continuing under Bush I). It was supposed to cost $8 billion all up and take 8 years.

    8 years and $8 billion later, nothing had been launched; hell, nothing had been built. The design had shrunk from a 12 man space station much larger (internally) than Skylab, to a 4 man station much smaller than Skylab. (The in-house joke at the time was that they had to call it "Fred" because they could no longer fit all the letters of "Freedom" on the side.)

    So in '96, Clinton forced an enquiry which required them to take what had been designed up to that point, pick one of the three leading configurations, and just build it. This led to the current design, then nicknamed "Alpha". In '98, a requirement was added to merge the station with Russian modules (and to a lesser degree Europa and Japan). This would reduce NASA's cost in developing some of the core modules, get modules launched earlier, and buy access to Mir technology/experience; it was also thought beneficial to keep Russia's space program intact, to prevent rocket engineers going to work for Iran/Iraq/etc. That became the ISS.

    As for "Powerpoint", it's clearly being used as a euphemism for the endless "paper studies" and over-management that infest NASA. You also know that, why are you lying and pretending that you don't?

  • Re:Just because... (Score:5, Informative)

    by Teancum ( 67324 ) <robert_horning&netzero,net> on Wednesday May 07, 2014 @10:13AM (#46939345) Homepage Journal

    >>I'm pretty sure NASA (and plenty of others) also said Elon/Space-X was stupid...

    Actually, didn't NASA award SpaceX a bunch of money to help get started... That's what I remember anyway. Do they help fund stupid?

    It was DARPA, not NASA, which gave some initial seed money to fly a few experimental payloads. Still, even that money was just a drop in the bucket for what was needed to get the rocket off the ground and certainly wasn't sufficient to pay for the development. All told, the development costs of getting the Falcon 9 ready were under a billion dollars, something a NASA study done a few years ago claimed couldn't be done for less than $10 billion.

    The DARPA money was just a few tens of millions of dollars. NASA has certainly paid for stuff like the ISS resupply missions (one is currently in space as I write this down), and they are also paying for a commercial crew program that also has money going to some other companies as well. Those were also highly competitive contracts that were literally open to any business or even group of investors who cared to put together an idea for a vehicle (including Jeff Bezos with his Blue Origin company who actually submitted a bid for that money too).

    Still, none of that would have been possible without substantial private capital including most of the private fortune of Elon Musk himself who has reportedly invested as much as $200 million of his own money into SpaceX.

  • Re:Just because... (Score:5, Informative)

    by jythie ( 914043 ) on Wednesday May 07, 2014 @10:18AM (#46939411)
    The idea that NASA has been poo-pooing SpaceX is mostly a myth. NASA has been urging caution and realism, but NASA has been on SpaceX's side from the early days. However people really get into the narrative of hip young capitalists taking on the stogy old government and shoe horn an adversarial narrative in.
  • by DerekLyons ( 302214 ) <fairwater@@@gmail...com> on Wednesday May 07, 2014 @10:20AM (#46939427) Homepage

    NASA found that it was not worth trying to reuse the space shuttle main engines after every flight without extensive refurbishment.

    *sigh* This myth again. Folks, this claim is a complete and utter fabrication. (And if you read TFA, it's not actually attributed to NASA.) By the mid-90's, while NASA was still removing the engines after each flight, this was solely for inspection - they no longer disassembled or refurbished them between every flight. By the late 90's/early 00's, they'd stopped routinely removing them after every flight, instead inspecting them with fiber optics and only removing them after every three-to-five flights or if inspection showed them to require removal. As is the case with so much science and technology journalism, the author is... not entirely aware of the facts or in possession of a clue. (Sadly, 90%+ of the Slashdot readers replying to this doesn't know these facts, and will attack the article anyhow because it disagrees with their biases.)
     
    That being said, I tend to agree somewhat with NASA on this one. SpaceX has reduced launch costs mostly by applying known engineering and production techniques that had not previously been applied to launch vehicles. (And with the limited number of launches to date, it's far too early to be reasonably analyze if they've truly been successful.) But when you're talking about flying an engine 40+ times... there aren't really any such previously known but unused techniques. They're headed off into largely unexplored regions of engineering and technology.
     
    Slashdot really needs to stop taking Musk's pronouncements as gospel at face value and look at the engineering and the facts.

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