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Transportation Technology

Airbus Unveils Its First Stage Reuseability Concept 100

schwit1 writes: The competition heats up: Airbus unveiled Friday its prototype design to recover and reuse the engines and avionics of its Ariane rockets. From the article: "The Airbus team concluded that SpaceX's design of returning the full stage to Earth could be simplified by separating the propulsion bay from the rest of the stage, protecting the motor on reentry and, using the winglets and turbofans, return horizontally to a conventional air strip. "We are using an aerodynamic shield so that the motor is not subjected to such high stress on reentry," [technical director Herve] Gilibert said. "We need very little fuel for the turbofans and the performance penalty we pay for the Ariane 6 launcher is far less than the 30 percent or more performance penalty that SpaceX pays for the reusable Falcon 9 first stage." Gee, for decades Arianespace and Boeing and Lockheed Martin and everyone else in the launch industry insisted it made no economic sense to try to recover and reuse the first stage of their rockets. Then SpaceX comes along and makes an effort to do so, without as yet even coming close, and suddenly everyone agrees it is economically essential to do it as well. Isn't competition wonderful?
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Airbus Unveils Its First Stage Reuseability Concept

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  • by wbr1 ( 2538558 ) on Saturday June 06, 2015 @07:25AM (#49855459)
    Why reuse something when you can trick governments to pay for it again. That make perfect economic sense until someone reveals the fraud.
    • by Anonymous Coward

      Especially considering that the one thing that Airbus is good at is extracting money from governments by being horribly inefficient and costly.

    • Why reuse something when you can trick governments to pay for it again. ...

      On the other hand, reused space vehicle components have caused some [wikipedia.org] problems [wikipedia.org] in the past.

      • by sjames ( 1099 )

        Neither of those was due to a reused component.

  • by taiwanjohn ( 103839 ) on Saturday June 06, 2015 @07:45AM (#49855527)

    If you just want to see how it works, scroll down to the video at the end. They don't really explain it very well in the text.

  • by Jane Q. Public ( 1010737 ) on Saturday June 06, 2015 @07:47AM (#49855529)
    The idea that SpaceX "did not even come close" is ridiculous. It was the FIRST to operate on the principle that it was practical, and has twice now come very close to getting it done. In only... what... 4 tries? On a target far smaller than the continents aimed at by Russia and EU?

    I find this whole announcement to be saying: "Yeah, us too! Maybe a few years from now."
  • Very "original" (Score:4, Insightful)

    by Dereck1701 ( 1922824 ) on Saturday June 06, 2015 @08:18AM (#49855619)

    So its basically the Vulcan concept, a detachable avionics/engine package at the back and an expendable everything else. I suppose its an improvement from what we currently have but not by much. The only real difference from Vulcan is that instead of being snagged out of the air by a helicopter it glides back to some location under some power. I suppose I can see why Airbus and ULA are going for such concepts, they should be pretty cheap to develop (though I am sure they'll try to squeeze every dollar they can out of their respective benefactors), are relatively low risk and will still let them justify big launch bills with tank/upper stage replacement. But if SpaceX can pull off a Falcon first stage recovery even a majority of the time they'll blow this and Vulcan out of the water. Fuel is cheap, replacing tanks and stages is expensive.

    • Agree. And assuming the Falcon Heavy flies as planned, there isn't much justification for SLS either. For the price of a single launch, you could fly at least 2 or 3 Falcon Heavies, and end up putting more mass on orbit. Since we're pretty experienced with rendezvous and docking, there's less need for such high throw-weight, even for large, complex missions.

      And eventually, SpaceX will come out with their new super-heavy (based on the Raptor engine) which will outclass SLS anyway, as they announced back in 2 [wikipedia.org]

      • by Rei ( 128717 )

        Of course there's a justification for SLS: jobs in congressmen's congressional districts.

        I reckon SLS will fly a few times (at most) and then be retired.

        Quite likely. The question is what congress will mandate has to be developed next to keep those people employed.

        • Yes, that's why it's nickname is the "Senate Launch System". ;-)

          The tragedy is, most of the people working at those jobs are really smart, highly skilled professionals who could do a lot of good for the amount of money we'll spend on them. Instead, we're going to waste both the money and their talents on a project that will at best enable an asteroid mission before it gets mothballed.

      • "you could fly at least 2 or 3 Falcon Heavies"

        And that assumes you believe NASAs "$500 Million per launch" statement (Buwahahahahhhahhhahaaa). SLS has more than earned its "Senate Launch System" title, with billions already spent and at least $22 Billion required just to get the first two of them off the ground with no real indications on how much it will cost to develop any actual mission hardware or finish the heavier versions of it.

    • Sounds logical.

    • Re:Very "original" (Score:5, Interesting)

      by Rei ( 128717 ) on Saturday June 06, 2015 @10:20AM (#49856123) Homepage

      When I think of "reducing costs", adding a couple turbofans to something doesn't jump to mind. Even if it gives them a better mass ratio than Falcon 9, that's a second powertrain to build and maintain. And then they have to rebuild the tank and re-mate it (although it saves some transportation costs).

      Might prove more economical, but I doubt it.

  • everyone else in the launch industry insisted it made no economic sense to try to recover and reuse the first stage of their rockets.

    Yes, that was then - long ago. Things are different now. For instance, who in the 90s, knew you could get 8GB of computer storage at less than $15 those days? It's reality now.

  • by goodmanj ( 234846 ) on Saturday June 06, 2015 @09:29AM (#49855865)

    This has the look of a paper concept that nobody's put any engineering work into yet. Some possibly show-stopping engineering challenges:

    1) The air-breathing engines are dead weight dragged most of the way to orbit. And turboprops and turbofans are pretty damned heavy compared to rocket engines: for many applications, the weight of fuel and tankage is so much greater than the engines that engine mass is irrelevant, but that's not the case here. SpaceX's design makes use of engines that need to go to space anyway.

    2) Looking at the videos, the design relies on folding propellers that deploy in flight. This is ... not an easy thing to do. I'm not aware of any aircraft larger than a duck that uses this technique, even on carrier-based aircraft where space is at a premium.

    3) While rocket engines are pretty lightweight compared to turbine engines, it's still a lot of weight to fly back home. The video shows a flyback aircraft with very short stubby wings. In addition, the wings can't be asymmetric lifting airfoils or they'd push the rocket sideways during lauch: the have to be flat boards. The return vehicle is likely to have a very high stall speed, making landing a challenge.

    4) The video shows no details on how this propulsion module is attached to the fuel tank above it. This is difficult: enormous fuel and oxidizer pipes need to pass through the nose of the propulsion module, along with gigantic clamps attaching it to the fuel tank... but this surface is exposed to re-entry heating on the flight back. How do you route plumbing and avionics through your heat shield?

    • This has the look of a paper concept that nobody's put any engineering work into yet.

      Hey now, don't be a downer! It works in Kerbal Space Program!

    • by sribe ( 304414 )

      I'm not aware of any aircraft larger than a duck that uses this technique...

      pGeese, eagles, condors... So there!

    • Re: (Score:2, Informative)

      by Anonymous Coward

      There's plenty of aircraft that have folding propellers, as long as you're willing to include rotors. Most naval helicopters have them, as do the V-22 Osprey. You don't see more of them, because propellors aren't nearly as big a space hog as the wings, which often fold. If you're willing to include motor gliders than there's also plenty of aircraft that deploy the folding propellor during flight.

      • Good examples, though these props will be operating at *much* higher speeds and stresses than a motor glider, and the Osprey's props don't unfold in flight. Well they're not supposed to anyway.

    • You seem to know a good amount about the design of rocket systems. I have a question for you. If reentry is so difficult, why not split stages earlier, before it becomes such a challenge? Aren't the currently used stage timings optimized assuming no reuse? What if you optimize for cost, and assume first stage recovery, but require a more manageable (earlier) split?

      • by goodmanj ( 234846 ) on Sunday June 07, 2015 @01:29AM (#49859929)

        I don't do this for a living, so don't take me too seriously. The smaller you make the first stage, the more work must be done by the second stage, which means *it* must be bigger, increasing the useless mass that makes it into orbit. Also, the smaller the first stage is, the less it costs, so it's less valuable to recover...

        You're absolutely right that there's an optimization problem to be solved here, and that a rocket optimized for first stage recovery might look very different from a stock Ariane 5 with wings on the bottom. But this rocket *does* look like a stock Ariane 5 with wings on the bottom, which makes me worry that they haven't done the math.

    • 2) Looking at the videos, the design relies on folding propellers that deploy in flight. This is ... not an easy thing to do. I'm not aware of any aircraft larger than a duck that uses this technique, even on carrier-based aircraft where space is at a premium.

      Look to the world of motor gliders - notably the Stemme S10 [stemme.ag].

    • by Agripa ( 139780 )

      I am dubious about the added weight as well but the turbine engines would not require a stored oxidizer saving some weight. I assume their fuel would be stored in the small wings.

  • Simplified? (Score:5, Insightful)

    by cjameshuff ( 624879 ) on Saturday June 06, 2015 @09:39AM (#49855919) Homepage

    "The Airbus team concluded that SpaceX's design of returning the full stage to Earth could be simplified by separating the propulsion bay from the rest of the stage, protecting the motor on reentry and, using the winglets and turbofans, return horizontally to a conventional air strip."

    Interesting definition of "simplified" they're using. They're not even recovering the entire first stage, and they're basically bolting a jet airplane onto it to achieve that much. Propellant is as cheap as dirt, they're avoiding paying tens of thousands of dollars in propellant by instead paying for jet aircraft maintenance and operations and an entirely new set of cryogenic tankage and a substantial amount of aerospace vehicle structure for each flight. SpaceX is just making the first stage a bit bigger (and looking at things like additional propellant chilling to increase density) so it has the extra capacity required.

    "We are using an aerodynamic shield so that the motor is not subjected to such high stress on reentry"

    Thus solving an issue that SpaceX has already shown isn't actually a major problem...they have been regularly bringing entire intact first stages through reentry and down to sea level for some time now.

    As for SpaceX not "coming close"...their second attempt actually brought the vehicle to a halt on the landing pad, though with mangled landing gear, and the reasons for the control issues during the final burn are well understood. They are extremely close...odds are quite good that their third attempt (in a bit under 2 weeks) will be a success.

    • by 0123456 ( 636235 )

      Thus solving an issue that SpaceX has already shown isn't actually a major problem...they have been regularly bringing entire intact first stages through reentry and down to sea level for some time now.

      But, at this point, no-one knows how much work will be required to refurbish those stages and fly them again. Until we actually have one land intact, rather than inpieces, we won't know. It could turn out that this method is actually cheaper than SpaceX returning the entire stage, though I doubt it myself.

  • 30% launch cost reduction is a huge deal. It is considered good ROI in many areas, so things which previously could only break even become financially viable, and in fact a risk worth taking.

    Here's to hoping they keep true to the 30%!

    • Reusing the engines would be a significant cost reduction, but they're going about it in a particularly complex way, and their level of reuse still falls short of their competition's. By their own statements, they throw away 20% of the economic value of the stage. SpaceX just needs to make the first stage a bit oversized for the second stage. That costs them a somewhat larger vehicle (which is reused for multiple launches, so this cost only has to be paid once) and propellant (which accounts for 1% of a lau

  • by Karmashock ( 2415832 ) on Saturday June 06, 2015 @10:14AM (#49856083)

    Is the airbus project worth anything? I have no idea. But the more money thrown at this issue the happier I am really.

    We need to get into space and we've allowed our space programs to atrophy.

  • by EnsilZah ( 575600 ) <EnsilZah@@@Gmail...com> on Saturday June 06, 2015 @10:41AM (#49856199)

    So they bolt on a pair of wings, add some propellers that have to be deployed from a casing that protects them during launch, oh and another stage separation event, a mechanism for separating the fuel tank from the engine.
    And that's supposed to be simpler than some hydraulic landing legs and grid fins?
    And carrying all those additions to space doesn't cost them any extra fuel?

    • So they bolt on a pair of wings, add some propellers that have to be deployed from a casing that protects them during launch, oh and another stage separation event, a mechanism for separating the fuel tank from the engine. And that's supposed to be simpler than some hydraulic landing legs and grid fins? And carrying all those additions to space doesn't cost them any extra fuel?

      Are you raging against this because it is a bad idea? Because it isn't an American idea? Because it wasn't thought up by golden boy Elon Musk? Or is it all three? The idea of landing the first stage like an airplane is a well understood process and it sure as hell seems simpler and more straight forward to me than what Musk is trying to achieve, which is to land a rocket standing up at the mercy if the wind; and simpler is usually better.

      • A first stage is not an airplane. Making it land like an airplane entails adding most of an airplane to it...wings, jet engines, unfolding propellers, substantial, steerable landing gear, various covers and other mechanisms that open and close in flight, mechanisms to detach the disposable tanks, etc. This is not making things simpler.

        • A first stage is not an airplane. Making it land like an airplane entails adding most of an airplane to it...wings, jet engines, unfolding propellers, substantial, steerable landing gear, various covers and other mechanisms that open and close in flight, mechanisms to detach the disposable tanks, etc. This is not making things simpler.

          And making a long cylindrical object landin end up on a platform in any kind of wind is simple?

      • I'm not raging against anything.
        I don't see why I should care if it was an 'American idea' even if I thought that was a meaningful distinction.
        I do like most of Elon's projects and I don't think he would have used a system like this because he's looking to build a rocket that could potentially land on Mars, but that's irrelevant.

        I merely object to this design being presented as 'simplified' and having 'no need for extra rocket fuel'.

        I personally find the SpaceX approach more elegant and I don't think that b

        • I'm not raging against anything. I don't see why I should care if it was an 'American idea' even if I thought that was a meaningful distinction. I do like most of Elon's projects and I don't think he would have used a system like this because he's looking to build a rocket that could potentially land on Mars, but that's irrelevant.

          I merely object to this design being presented as 'simplified' and having 'no need for extra rocket fuel'.

          I personally find the SpaceX approach more elegant and I don't think that because we've had a hundred years of air flight experience that makes it any simpler or better of a solution.

          I don't see the elegance. It is overly complicated. I have worked around tall structures long enough to know what wind will do to something like an antenna mast or wind generator mounting column floating in mid air under a crane and I don't expect it will do anything much different to a rocket trying to land end up. If Airbus can really add airplane parts to a rocket stage using ultra light high strength modern composts and land the thing like an airplane that and do it in a fairly broad range of weather co

    • > So they bolt on a pair of wings, add some propellers that have to be deployed from a casing that protects them during launch, oh and another stage separation event, a mechanism for separating the fuel tank from the engine.

      I do not think you know what a turbofan is based on what you stated.

      > And that's supposed to be simpler than some hydraulic landing legs and grid fins?

      Not simpler to build and package, but certainly far easier to land given that we have 70 years of experience building jet engines

      • I do not think you know what a turbofan is based on what you stated.

        The article mentions "turbofans" but the video at the bottom of the link clearly shows external propellers (i.e., a turboprop). It's the article that's confused, not the grandparent poster.

        It does - but turbofans and horizontal flight with lifting surfaces is far more efficient than attempting to land vertically using a rocket engine, and we have 110 years of experience landing aircraft horizontally, or if you want to combine total experie

        • The way SpaceX is trying to recover the booster is like catching a bullet in your teeth. They have only a second or two of usable thrust, since the Merlin engines don't have enough throttle range to land at a nice gentle pace. But what if they developed a "Merlin DT" (Deep Throttle[TM]) and used that for the center engine? Even if the Merlin-DT was less efficient, it's only one of nine, so you could optimize it quite easily over the whole flight profile.

          If you had that one center engine with enough throttle

          • It's already been shown that the SpaceX design can get within 105m of a landing pad. If it ends up being too difficult to finish the landing as is, adding more landing site sensors to improve prediction, and adding a catching mechanism should solve the problem. And note that all of these additions are one-time costs that don't have to be lifted to 100km. My money works definitely be on the spacex design.

  • They're right that reusability doesn't make much economic sense at current flight rates. NASA and Boeing looked at recovering Saturn V stages in the 60s, and determined that they'd need about 60 launches for the development and operational cost of recovering and refurbishing the stages to become lower than just throwing them away. This would probably require less, as they wouldn't be dumping the stage into the sea and trying to clean it up, but it will still probably require quite a few years at current lau

    • Note, though, that spacex is using payed-for launches to test its recovery system. Thus, the development costs are much lower than they could be.

  • Large government contractors live or die suckling the tits of taxpayers... and their internal goal is NOT to solve the problems they're brought in to solve (the paperless initiative to reduce costs and ALSO as a side effect make all government records indexable and searchable for example) but to maximize billable hours.

    It makes perfect sense to say it isn't economically feasible to make the first stage of spacecraft reusable; because for them it ISN'T an economically sound business model. It would reduce th

    • Scaled already built a close air support prototype -- http://en.wikipedia.org/wiki/S... [wikipedia.org]. The world hasn't beaten a path to their door to buy them. I agree that the legacy aerospace contractors are crooks, but competitive modern fighters are extremely complex in every domain -- structural, propulsion, avionics. Ask the Russians and Chinese how well their 5th gen fighters are coming. I respect Scaled but Spaceship Two is a LOT simpler than a 5th gen fighter and it is not coming along so well.

      • > Ask the Russians and Chinese how well their 5th gen fighters are coming.

        Russia's aircraft are actually quite good. For example, he F-15 was developed in response to rumors of the MiG-25... but performance was inferior. The design of the MiG-25 is so good it is the basis for the MiG-31, and is also rumored to be the basis for a MACH 4-capable interceptor... same basic design but with modern materials and construction techniques. Also other Russian (Soviet?) military aircraft were historically superior

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