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Space Technology

SpaceX Launch Not So Perfect After All 272

First time accepted submitter drichan writes "Those of us who watched the live feed of last night's Falcon 9 launch could be forgiven for assuming that everything went according to plan. All the reports that came through over the audio were heavy on the word "nominal," and the craft successfully entered an orbit that has it on schedule to dock with the International Space Station on Wednesday. But over night, SpaceX released a slow-motion video of what they're calling an 'anomaly.'"
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SpaceX Launch Not So Perfect After All

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  • An (Score:5, Funny)

    by JustOK ( 667959 ) on Monday October 08, 2012 @03:06PM (#41589677) Journal

    An anomaly? That's strange.

  • Whats the problem? (Score:5, Informative)

    by ZiakII ( 829432 ) on Monday October 08, 2012 @03:10PM (#41589723)
    The Falcon 9, as its name implies, has nine engines, and is designed to go to orbit if one of them fails. On-board computers will detect engine failure, cut the fuel supply, and then distribute the unused propellant to the remaining engines, allowing them to burn longer. This seems to be the case where that was required, and the computers came through. The engines are also built with protection to limit the damage in cases where a neighboring engine explodes, which appears to be the case here.

    Sounds like it did exactly what it was supposed to do.
    • by residieu ( 577863 ) on Monday October 08, 2012 @03:12PM (#41589753)
      Just because you have a backup plan, and it works, doesn't mean the launch was perfect.
      • by Maximum Prophet ( 716608 ) on Monday October 08, 2012 @03:18PM (#41589807)
        Pilots say any landing you can walk away from is a good landing.

        In space, any launch that accomplishes its goals is a good launch. If good costs 10% of perfect, go for good.
        • by TWX ( 665546 ) on Monday October 08, 2012 @03:41PM (#41590083)
          Obviously SpaceX wants to achieve man-rating so that they can launch and return personnel in addition to the cargo runs they're currently beginning. I'm curious as to how this moderate malfunction will impact the rest of the program.

          Bearing in mind, of course, the deaths of Chaffee, Grissom, and White in the Apollo 1 accident, the launch-time engine failure and later unrelated catastrophic failure for Apollo 13, the Challenger disaster, and the Columbia disaster, it's difficult to call SpaceX's anomaly as being any worse than those. If SpaceX manages a series of cargo deliveries without any loss of the capsule or with complete success on delivery then even with this anomaly they're arguably no worse off than any of the previous space programs were, as far as reliability and safety goes.
          • by Electricity Likes Me ( 1098643 ) on Monday October 08, 2012 @04:03PM (#41590337)

            Obviously SpaceX wants to achieve man-rating so that they can launch and return personnel in addition to the cargo runs they're currently beginning. I'm curious as to how this moderate malfunction will impact the rest of the program.

            Bearing in mind, of course, the deaths of Chaffee, Grissom, and White in the Apollo 1 accident, the launch-time engine failure and later unrelated catastrophic failure for Apollo 13, the Challenger disaster, and the Columbia disaster, it's difficult to call SpaceX's anomaly as being any worse than those. If SpaceX manages a series of cargo deliveries without any loss of the capsule or with complete success on delivery then even with this anomaly they're arguably no worse off than any of the previous space programs were, as far as reliability and safety goes.

            The important thing is whether they can successfully determine what actually happened, and why it happened (i.e. replicate the malfunction on a test bed engine). This was the thing Feynman was most critical of NASA for post-Challenger - that the whole disaster was caused by this faulty assumption about engineering risks on the O-Ring seals (i.e. the seals were getting eroded by exhaust during launch, but the question posed was "is this dangerous" not "why is this happening" - the former being foolish since the system was not designed to cope with this, and it's true cause was unknown).

            It's a triumph that the launch still succeeded, but having averted an unforeseen consequence the only safe thing to do is make sure it's both forseen and mitigated in the future.

            • by TWX ( 665546 ) on Monday October 08, 2012 @05:14PM (#41591033)
              Very true, especially in the infancy of SpaceX's program. I do hope that they figure out why the engine failed, and hopefully their records on its manufacture and testing prior to its use will contribute toward answering that.

              I'll have to ask my wife about it- she actually is a rocket scientist, albeit one that deals with solid rockets, not liquid, but I'd expect that the post-failure analysis would follow the same kinds of procedures.
            • by dbIII ( 701233 )

              the seals were getting eroded by exhaust during launch

              No it was a known glass transition temperature problem - the o-rings were not safe to use below a known temperature. It's the sort of problem where you can soak a squeaky rubber toy in liquid nitrogen for a while, then pull it out and shatter it with a hammer.

          • by cplusplus ( 782679 ) on Monday October 08, 2012 @05:24PM (#41591119) Journal
            The Ars Technica article states that Apollo missions had the same protections against engine failure, and that two of the Apollo missions actually suffered engine losses and still completed the mission. So, maybe there's precedent?
        • by cwebster ( 100824 ) on Monday October 08, 2012 @04:29PM (#41590585)

          A landing you can walk away from is a good landing... A landing when you can re-use the airplane is a great landing.

    • Re: (Score:3, Insightful)

      by Hentes ( 2461350 )

      The fact that the rocket had enough redundancy built in doesn't mean that the cause of the failure should not be investigated.

    • I don't think it's the fact that there was a failure, or the fact that the system proved resilient, it's the manner in which the failure manifested itself - an engine cutout, a fuel pump failure, or a vibration issue would be cause for a post launch investigation and a pat on the back, while a wholesale engine disintegration will trigger quite a significant inquiry and a heck of a lot of furrowed brows.

      It's the difference in magnitude of failure which is the thing to note here.

  • by wierd_w ( 1375923 ) on Monday October 08, 2012 @03:12PM (#41589755)

    The engine failure of the falcon 9 engine #1 is not really a bad thing. It served to prove the reliability of the shutoff system, and flight control hardware.

    Considering the horrendous failure rate of NASA's early engines, (the kind that explode spectacularly), this managed failure situation is very promising.

    Rest assured, there will likely be a strong inquiry concerning the manufacture and design of the engine fairing that failed, causing the pressure drop, and engine shutdown.

    Managed failures like this one don't speak poorly of spacex. On the contrary. They show spacex planned ahead, and the failsafes they built actually work.

    • by Virtucon ( 127420 ) on Monday October 08, 2012 @03:38PM (#41590017)

      Not just Early Engines..

      Let's see, there was the Titan IV which took out a facility at Edwards AFB on April Fools Day in 1991. [nytimes.com] Now that was an Air Force engine, but fairly modern. There was another Titan IV which exploded in more spectacular fashion. [nytimes.com]

      Recently, we have the NASA Morpheus Lander Explosion. [csmonitor.com]

      Then there's the Delta II, which is a newer launch system which has exploded at least twice that I'm aware of. Once in 1995 [youtube.com] and another in 1997 [nasa.gov].

      The point is that NASA and the Air Force and their various subcontractors, SpaceX not included, don't have a perfect record on launch vehicle malfunctions. You can't have lots of propellant with oxidizer burning without some sort of malfunction. While still rare, these events can and do happen and it's good to see SpaceX plan for these kinds of things unlike the Soviets did when their Moon Rocket went "boom" when they were testing in the 60s [youtube.com] In Fact, all four launches of the N-1 were failures. [starbase1.co.uk]

    • by Teancum ( 67324 )

      The interesting thing is what may be a failure of the orbital insertion of the Orbcom satellite that was supposed to use the 2nd stage of the Falcon 9 for an additional burn after separation of the Dragon. Apparently either due to this engine loss of the 1st stage or some other problem, that satellite didn't get to the desired orbit.

      It will be interesting to see if SpaceX will refund Orbcom their money or do something extra to help them out.

      • If the ascent vector isn't correct, (which it wasn't, due to the failure), then the entry vector for the capsule will be different from the one planned. This is the likely cause of the orbcom deployment snafu.

        It's basic geometry. The angle changed, so the insertion point changed. (The tangent intersection of the satelite orbit relative to the ascent vector) That's why the sat isn't in the proper place.

        • There was nothing wrong with the insertion. The Falcon 9 actually shuts down two engines [nspo.org.tw] during late flight of the first stage so as to not exceed 5g acceleration anyway. The reason the sat didn't get into it's proper orbit is because they weren't permitted to perform the required re-igniting of the second-stage after sending Dragon on it's merry way due to rules placed upon them by NASA and co. the first-stage engine out (see above for links).
      • by Nethemas the Great ( 909900 ) on Monday October 08, 2012 @07:04PM (#41591869)
        Actually there was nothing preventing the Orbcom sat from being inserted into the proper orbit but for rules by NASA and their ISS partners (Russians) that told them that they were not allowed to reignite the second stage [orbcomm.com] because of the malfunction in the first stage.
    • by Kjella ( 173770 )

      I think that highly depends on whether there's any more engine failures on the next flights. If it seems like an odd case and SpaceX can say that "and even such a thing were to happen again, we'd catch it" then all is well. If another one fails and it smells more like "our engines aren't exactly 100% reliable, but we're betting on statistics that two of them won't fail on the same flight" then that's not good.

    • Rest assured, there will likely be a strong inquiry concerning the manufacture and design of the engine fairing that failed, causing the pressure drop, and engine shutdown.

      You've got the chain of events backwards.
      A loss of fuel(?) pressure forced an engine shutdown, which caused a pressure drop at the engine's nozzle, which caused the engine fairing to fail.

      • That makes sense...

        I'd hold off on speculation until after forensic evaluation of the failed component (if it doesn't burn up in re-entry), and failure data sent from the vehicle. All we know for sure is that the safety kicked in, and the engine shut down.

        I would expect a full inquiry as to why this happened. That's all.

        *shrug*

  • Not all the info (Score:5, Informative)

    by Antipater ( 2053064 ) on Monday October 08, 2012 @03:13PM (#41589765)
    TFA only tells half the story. MSNBC [nbcnews.com] has more. Dragon is fine, but it's possible that the launch's secondary objective, which was to put the first of an 18-satellite telecom array into a tricky high-inclination orbit, went a little screwy as well, and the sat isn't in the proper orbit at the moment. Details are still being dug out.
    • by zrbyte ( 1666979 )

      Well apparently the SpaceX update in TFA says otherwise:

      there was no effect on Dragon or the cargo resupply mission

      • Re: (Score:3, Informative)

        by Antipater ( 2053064 )

        Dragon is fine, but...

        Did you miss that part of my post? The telecom satellite is separate from the resupply mission.

    • by 0123456 ( 636235 )

      Apparently the second stage didn't hit the required orbit for NASA to allow them to restart it without risk of collision with ISS if something went wrong. So it looks like SpaceX could have restarted the stage but NASA didn't let them; it was a consequence of the first stage engine failure, not a second failure.

  • by Samantha Wright ( 1324923 ) on Monday October 08, 2012 @03:15PM (#41589783) Homepage Journal
    – Both Saturn V and the shuttle launch system were designed to handle failure of at least one engine
    – The entire engine didn't actually explode, as some sources have reported; the onboard computers were still sending data from it (SpaceX believes it was just the aerodynamic casing (fairing) that exploded, due to the pressure release of the engine)
    – This doesn't mean the Falcon 9 system is necessarily less safe than NASA systems; on two occasions, Saturn V rockets experienced a similar loss, with similar (i.e., nil) impact to the mission's success

    So, y'know. Rejoice nerdily about the fact that the failsafes worked, rather than worrying about commercial technology being inferior.
    • Both Saturn V and the shuttle launch system were designed to handle failure of at least one engine...

      The shuttle can get to orbit with just two of the liquid fueled engines, but was designed to return with just one. Turns out, you can deorbit a shuttle with just the maneuvering jets.

      Unfortunately, a failure of the solid fueled boosters, is mostly fatal.

      • The shuttle can get to orbit with just two of the liquid fueled engines, but was designed to return with just one. Turns out, you can deorbit a shuttle with just the maneuvering jets.

        Unfortunately, a failure of the solid fueled boosters, is mostly fatal.

        I'm thinking that's because the orbiter was bolted onto the side of the launch vehicle. I'm thinking, if it would have been mounted on top like a normal capsule, it probably wouldn't have killed that crew. But hey, IANARS, so my opinion means shit.

        • by 0123456 ( 636235 )

          I'm thinking that's because the orbiter was bolted onto the side of the launch vehicle.

          To a large extent it's because it had wings. If you need wings to land and they fall off, you die.

          Surviving a launch accident in a winged rocket is very hard, because you have to get from flying vertically to flying horizontally at supersonic speed without anything falling off. Normally the best you can do is fit ejection seats and cross your fingers as you pull the handle.

          The X-20 with an escape rocket below the spacecraft was probably the closest to being survivable and the tests for that looked pretty ha

    • due to the pressure release of the engine

      I read this in the official statement too - I'm guessing it makes perfect sense to rocket scientists.

      My best guestimate: because of the sudden lack of exhaust gasses from the engine, the pressure inside the fairing changed extremely significantly and quickly, and the fairing couldn't take the pressure delta, so it ripped apart.

      Somebody correct me.

  • How many of those nine engines can fail before the system cannot compensate?
    • I guess it depends on "where" (when?) they fail. In fact, at some point two engines are shut down to avoid too much g - probably at that point three failing engines could still be OK?
    • For the first stage, one at launch, two later on. From a strict physics perspective, you could probably have three or four out in the last few seconds of the burn, but I don't know if their software is that clever. The second stage has only one engine.

  • by Fuzzums ( 250400 ) on Monday October 08, 2012 @03:35PM (#41589989) Homepage

    9 engines of LOX on the rocket, 9 engines of LOX
    drop one down, blow it around
    8 engines of LOX on the rocket....

  • I've been playing too much SpaceChem...

  • by m0s3m8n ( 1335861 ) on Monday October 08, 2012 @03:59PM (#41590301)
    Did anyone here a call of engine cut-off in the NASA TV feed? I did not. Or a call for a longer burn? Seems the SpaceX team would have made those calls. Of course, they could have on private channels. Seems NASA was more transparent. Also, when I fly I like my pilots to be well dressed and professional. The SpaceX team did not. Maybe that is the SpaceX culture, but I am an old fart and I prefer a much more orderly look.
    • Time to let go of the white shirt/thin tie/pocket protector/black rimmed glasses look. T-shirts are the new uniform. Hair length is not a factor.

      I know, I hate it too, but we are not far from everyone on the launch team Skyping in and being avatars on a plasma screen in front of the media videoconferencing system.

    • I missed the launch, and I haven't been able to find a recorded feed: if anyone has a link I'd love to hear the flight loop.

      BUT, the mission control chatter you hear on a SpaceX launch is almost entirely people assuring themselves that the rocket is OK. They're not *controlling* much of anything: it's all in the hands of the flight computer, which decides things like "shut down this engine and recompute a launch profile for the remaining 8 engines" on its own, in real time. There's no time for humans to m

      • I was not trying to say they would have had to do any manual intervention, and I would fully exept them to NOT have to, just like what happened last night. But as you mentioned, it did not appear like they noticed. Anyhow, I am glad the SpaceX engineering effort paid of. Good job.
    • Did anyone here a call of engine cut-off in the NASA TV feed? I did not. Or a call for a longer burn? Seems the SpaceX team would have made those calls.

      The decision to shut down engine #1 and the decision to adjust the other engines' burns to compensate were made automatically by the flight-control computer onboard the rocket. There's no need for the ground team to make the decisions, and no need for the computer to make voice announcements about them.

      (Obligatory car analogy: it would be like having your c

      • Your points are well taken, but in reviewing the NASA feed, the voice-over clearly stated that "all nine Merlin engines ... continue to burn ..." after 2 minutes. I believe this was a NASA voice-over, so that may be where the discrepancy happened. As for your analogy, I agree, but given today's techno-crap most cars are coming with, it would not surprise me if this does not happen in the near future, say for low breake fluid or cylinder misses.
    • by mark99 ( 459508 )

      I don't care how they dress. I thought the "Mohawk guy" on the Curiosity landing was pretty cool. So do most others I believe.

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