SpaceX Falcon 9 lost an engine on the way up; Dragon on its way to ISS

By Phil Plait | October 8, 2012 9:20 am

Last night (Sunday October 7), SpaceX launched a Falcon 9 rocket with a Dragon capsule full of supplies on a mission to the International Space Station. The Dragon was deployed successfully (as were its solar panels to give it power) and it’s on its way to ISS.

However, not everything went as planned. One of the nine Merlin engines powering the Falcon 9 had a failure 90 seconds into the flight. It’s not clear what happened just yet, but there is pretty dramatic footage of the engine failure; in the slow motion video below you can see some sort of flash and puff of flame at the 30 second mark (I’ve set the video to start 22 seconds in):

You can see a bright spot glowing on the upper right engine, then what looks like shrapnel blowing back as well, so it appears something catastrophic happened to the engine. I can think of many things that could’ve caused this – a crack in the engine bell that failed when it got hot, a faulty valve, something in the pipes – but I’m just spitballing; hopefully the folks at SpaceX will be able to determine the cause from the engine telemetry.

[UPDATE: SpaceX issued the follow notice at 17:00 UTC today:

"Approximately one minute and 19 seconds into last night’s launch, the Falcon 9 rocket detected an anomaly on one first stage engine. Initial data suggests that one of the rocket’s nine Merlin engines, Engine 1, lost pressure suddenly and an engine shutdown command was issued immediately. We know the engine did not explode, because we continued to receive data from it. Our review indicates that the fairing that protects the engine from aerodynamic loads ruptured due to the engine pressure release, and that none of Falcon 9’s other eight engines were impacted by this event.

As designed, the flight computer then recomputed a new ascent profile in real time to ensure Dragon’s entry into orbit for subsequent rendezvous and berthing with the ISS. This was achieved, and there was no effect on Dragon or the cargo resupply mission.

Falcon 9 did exactly what it was designed to do. Like the Saturn V, which experienced engine loss on two flights, Falcon 9 is designed to handle an engine out situation and still complete its mission."]

Although this looks scary, the engine nozzles are coated with Kevlar to protect them specifically in case something like this occurs, so the other engines continued working. Also, the onboard computer immediately shut down the failed engine, and then on the fly – literally – recalculated all the needed changes to the thrust of the other engines to compensate. In the end, the first stage boost lasted an extra thirty seconds to cover for the failed engine. It’s important again to note that the Dragon capsule was delivered on orbit and will rendezvous with ISS on Wednesday.

Having said that, there may have been another problem as well: my friend Jonathan McDowell of Jonathan’s Space Report is reporting the upper stage didn’t make its second burn, so an Orbcomm satellite that was carried as a secondary payload didn’t make the correct orbit. I don’t have any more information about that, but I’ll update this post when I hear more.

[UPDATE: ORBCOMM has confirmed the satellite was placed into the wrong orbit due to the engine failure. They, along with aerospace company Sierra Nevada, are looking into using the satellite's onboard propulsion system to raise the orbit.]

Elon Musk at SpaceX is expected to have an announcement later today about the launch. Again, I’ll update this post as info comes in.

Tip o’ the nose cone to AstroEngine for the alert about the video.

CATEGORIZED UNDER: Space

Comments (85)

  1. No surprise. Rocket engines have an incredibly high energy density–having one fail is is a bummer, and points out a flaw in the engine, but that’s the nature of the business.

    But I watched that launch. Everything, all the way until well after the second stage ignition looked to be completely nominal, and they even said so. I would think that at some point the controller would mention that an engine had failed and that the trajectory was being adjusting. Nothing like that went over broadcast. There was certainly no mention that the first stage had burned 30 seconds longer than had planned.

    Craig Steffen

  2. jb

    i think it is the turbo pump that has kevlar not the nozzle… either way.. glad dragon made orbit
    jb

  3. Any idea how many engines can fail without destroying the rocket or sending it irreparably off-course?

  4. Paul

    That’s an impressive, if pants staining, demonstration of the capability of the vehicle.

  5. Ferris Valyn

    Bob

    I believe (but may be wrong) that they can withstand a single engine loss, but not 2 engine loss

  6. jb

    @bob depends upon when the engines go out…the current design (V1.0) has two engines shut down early due to too large a thrust a few seconds before all engines shut down. The next version (V1.1) have the engines throttle down. the current engines Merlin 1-C can’t throttle. the 1-D can throttle. so there is no “simple”answer…best to not lose any :)
    jb

  7. Heliantus

    An interesting (frightening, but successful) demonstration of the term “failsafe”.
    Or of the importance of redundancy in engineering.

  8. Chris

    In a way this is good, they have redundancy and safeguards that work. Also keeps them on their toes. We don’t want them getting overconfident when they start sending up human cargo.

  9. Charles Boyer

    Sounds like SpaceX has had its Apollo 6.

    The pogo effect experienced by the S-1-C is pretty well known.

    Also in that flight, Engine 2 of the S-II second stage shut down at t-plus 412 seconds after experiencing problems for a little over three minutes of operation. At t-plus 414, Engine 3 also shut down.

    Later in that same flight, the S-IVB failed to reignite to propel the vehicle’s translunar orbit burn.

    Despite those anomalies, the mission was considered a success, and after the SM/CM was tested in orbit during Apollo 7, the next launch of the Saturn V was humanity’s first foray past Earth orbit, Apollo 8.

    I predict the same sort of success for SpaceX. These guys have been very good so far at finding and fixing their problems.

  10. F9 can withstand a two engine loss, but it depends on when the engine loss happens. I don’t think it can compensate for any engine loss in the first 10′s of seconds.

    Phil, folks on the NASASpaceFlight.com forum (you should pop over there some day ;-) ) are saying that the Orbcomm satellites had a release to a lower orbit as a backup, in case there were issues with the second stage. It’s possible that the failed first stage engine resulted in the second stage having to burn longer to put Dragon (the primary payload) into the correct orbit, leaving below nominal fuel for the preferred Orbcomm orbit. Also, these are test satellites for Orbcomm, not the final production models.

  11. Renee Marie Jones

    Wow. I am incredibly impressed that it could survive a catastrophic failure like that and still succeed with its primary mission. It is a bit terrifying, too.

  12. Robin

    In the video it looks like the failed engine powered down just before the apparent destruction of at least the nozzle.

  13. Mejilan

    I think it says a lot about the vehicle’s design that it can experience an engine failure and still hope to accomplish at least part of its mission. This could very well have turned into a ‘total loss’ type scenario. Amazing stuff. I hope it pulls through and succeeds in its mission.

  14. TxSkeptic

    The wiki on the Falcon 9 says SpaceX plans eventually recovering & possible reuse of 1st and 2nd stages, but has not recovered any to date, and didn’t think it would happen until flight 6. (this is 4) Maybe this is a good one to go after for failure analysis.

  15. So is this good news for private spaceflight, since it demonstrated a pretty impressive failsafe recovery, or is it bad news since they needed to rely on such impressive failsafe ability on only the second ISS flight?

    I’m genuinely curious what your (and others’) read is on it. I could see the chips falling either way.

  16. eyesoars

    SpaceX claims that the engine did not explode, but that the fairing around engine 1 apparently came apart after the engine was shut down, and it seems to imply that this was perhaps because the engine was shut down (decreasing the internal pressure on the fairing). This happened around the time of MaxQ, or maximum aerodynamic load on the vehicle during launch.

    This seems plausible to me — if an engine actually blew up, there’s no doubt in my mind that, kevlar or no kevlar, it would take out engines around it.

  17. Adam

    I view this as a good kind of thing. They had a failure and demonstrated that their vehicle is capable of automatically compensating. Their forward thinking in designing the rocket and flight control software was validated. They thought of a possible failure and designed a fix for it should it happen in flight. Of course they will look into what happened and make design changes to minimize the chances of this happening again, but as this launch stands, they did a phenomenal job designing for it.

  18. Adam S

    @James – From the official (and obviously biased) statement, not to mention other comments upthread, it sounds like NASA’s own rockets had the same capability. It’s impossible to make a system as complex as a liquid-fueled rocket work flawlessly 100% of the time; the best you can do is anticipate the failures, and compensate for them when they occur.

  19. Wzrd1

    @ TxSkeptic, agreed. This SHOULD be recovered for a failure analysis. There isn’t much room for error in space flight.

    @eyesoar, given the flare from the engine exhaust, this looks more like either a fuel line failure or turbo pump failure that blew some of the fairing off. An engine shutdown shouldn’t cause such stress as to cause the faring to depart the rocket. Once supersonic, one can never accurately ascertain WHERE an object departing the booster body could fly into, including engine bells or other components, not to mention adding asymmetric stresses on the rest of the fairing and flight profile as it is departing the booster assembly.
    PR announcements tend to downplay events, no need to make investors nervous.
    Frankly, considering the failure and mild impact on flight profile, the design appears to be quite in the excellent range. It wasn’t so long ago that such a failure would destroy the entire stack, probably even the payload as well.

  20. Tall Blue Ape

    Wow. I’m a programmer, and I’m having a hard time fathoming how you would even come up with software so ass-kickingly responsive that it can near instantaneously recompute the required trajectory with the sudden new thrust available to it… no wonder it’s called ‘rocket science’!

  21. Paul

    It should be pointed out that a Delta 4 launched last week also had a performance issue, but was also able to compensate and deliver the payload to the intended orbit. So robustness in the face of problems is not something unique to the Falcon 9.

  22. Larry Bruce

    Actually this makes me feel better. You know it has to fail at some time, I am uncomfortable with a machine that’s not yet had a failure that you can analyze.

  23. dessy

    I see this as good news…

    It demonstrated the effectiveness of the failsafe systems, the engineering redundancies and confirmed the efficacy of the engineering itself.

    Its also an excellent opportunity for data feedback into the design. You learn more from errors than successes. I would actually be more concerned if 8-10 flights were achieved without a single testing of failsafe systems. The tendency would then be to question whether they should be made less robust or whatever to shave costs. This demonstrates need and effectiveness, and data.

    ….and orbit was still attained! Well done SpaceX.

  24. DanM

    I was vaguely bothered by the idea of a falcon carrying a dragon. Dragons are supposed to be much bigger, and fire-breathing. I think they got their names reversed. Perhaps that is the origin of the failure.

    Grin.

  25. MattM

    The ORBCOMM satellite was indeed released into a lower-than-intended orbit.

    http://www.orbcomm.com/Collateral/Documents/English-US/ORBCOMM%20Launches%20Prototype%20OG2%20Satellite%20FINAL.pdf

    “However, due to an anomaly on one of the Falcon 9’s first stage
    engines, the rocket did not comply with a pre-planned International Space Station (ISS) safety gate
    to allow it to execute the second burn. For this reason, the OG2 prototype satellite was deployed
    into an orbit that was lower than intended”

  26. Checkmite

    It’s very fortuitous that Falcon’s flight computer was able to compensate for the in-flight failure and that the Dragon vehicle made it up OK.

    But unlike most people here so far, I can’t honestly claim to be impressed. If this kind of thing is what we’re going to have to expect from Falcon 9 launches – engines failing, pieces of the rocket falling off, the vehicle having to resort to emergency measures to successfully complete it’s mission – I’m sad to say I don’t find that very impressive. I suppose I could cut the system some slack for being new; but we’re not talking about a brand new experimental rig here. Falcon 9 is out of the testing phase and is supposed to be bowling for dollars now.

    Even all that isn’t so bad; what really has me disappointed is the fact that nothing – not the engine issue, nor the 30 extra seconds of burn – was mentioned or even hinted at on the broadcast feed. It launched, they narrated some telemetry once in a while, and then triumphantly announced when Dragon separated. There wasn’t even a whisper about the secondary payload. By the time the event ended I’d been given the impression that the launch had been perfect; I didn’t find otherwise until today. I guess I’m used to watching NASA feeds were information like this, even in the case of failures, is given in almost realtime when it happens.

  27. Kevin

    #34 Thank you. You said this before I got here to say the same thing. I’m not all that excited about private space ventures. It is so hard to get information. Prior to the first launch of the Falcon 9, it was nothing but sanitized press releases. Now that they are launching, more corporate nonsense-speak after a failure. At least with NASA launches, you were aware of what was going on in real time, and got a fairly technical after action summary. I’m guessing the full analysis of this anomaly will not be available to the public.

    I’m just not as excited about private space companies as Phil and others around here are.

  28. Robin

    @ Checkmite (#34):

    In space flight, you’re never “bowling for dollars”, free from the worry of what could go wrong. This is only the Falcon 9′s fourth flight. You should note that the Apollo program had two engine out episodes in its first 13 flights, one of which saw 3 engines lose power. Other “anomalies” are more well known: the tragic fire in Apollo 1 during a plugs out test on the pad and the explosion of O2 tank on Apollo 13′s service module (13 was also the second of the engine out episodes, as they lost a second stage engine).

    The Delta IV had an engine out on its fourth flight.

    There’s no doubt that SpaceX will have to get to the bottom of the engine failure and take what ever corrective action is necessary, but the latest Falcon 9 flight did demonstrate a system capable of completing its mission despite the loss of an engine. That’s big. It means what SpaceX learns from this engine failure will lead to an even more robust Falcon 9.

  29. Jake

    Actually, the Orbcomm satellite was able to be launched into the window but was not able due to safety reasons with the ISS.

    http://www.orbcomm.com/Collateral/Documents/English-US/ORBCOMM%20Launches%20Prototype%20OG2%20Satellite%20FINAL.pdf

    “However, due to an anomaly on one of the Falcon 9’s first stage engines, the rocket did not comply with a pre-planned International Space Station (ISS) safety gate to allow it to execute the second burn. For this reason, the OG2 prototype satellite was deployed into an orbit that was lower than intended. ORBCOMM and Sierra Nevada Corporation engineers have been in contact with the satellite and are working to determine if and the extent to which the orbit can be raised to an operational orbit using the satellite’s on-board propulsion system.”

  30. And if had been Engine #5 that had had that little shutdown and which had thrown that much crap out, the results would have been the same?

    I just don’t think so.

  31. Checkmite

    @ Robin (post 36)

    At least, we’ll have to presume that what SpaceX learns from the engine failure will lead to a more robust platform; it’s not at all certain that we’ll be privy to the results or findings of any studies they do.

    Unlike Kevin, I do like to think I’m excited by private space flight; I want SpaceX to succeed. I tuned into the feed last night because I wanted to see success, not failure. I will tune in to watch the next launch also, for the same reason. And I’m not going to say the platform is worthless because of one imperfect launch. But like Kevin, I’m disappointed in what I consider to be a distinct lack of transparency on the part of SpaceX over yesterday’s mission. Not only did the commentator on their live launch feed pretend nothing was wrong at the time, but they didn’t even seem to feel the need to say anything about the events subsequently – until independent observers discovered the problems on their own and caused a stir.

    Once again I’ll submit that perhaps I’m spoiled by NASA launch coverage in the past. Where the commentator informed us of issues like these and there were post-launch press conferences/releases after every launch where problems, even ones they were still figuring out, were discussed or explained. I wonder; is it unfair to expect this same kind of openness from a private company? I’m willing to hear an argument if anybody wants to make one; but until then I’m going to be less than impressed over this performance.

  32. Robert

    A poster over at arstechica pointed out that, upon loss of a fairing, the air flow would have been chaotic until new shockfronts formed and the flow settled down around the new shape of the rocket’s rear end.
    This could well have caused the disturbances in the exhaust pattern that we are seeing as an explosion or a venting of unburnt fuel. Also, it appears that, just before this, the craft seems to enter some thin cloud, further obscuring what happened. (could air turbulence be involved?)

    Engine shutdown for some boring reason, followed by the failure of the cowling under aerodynamic loads, is just as likely as any more dramatic scenario.

  33. VinceRN

    “As designed, the flight computer then recomputed a new ascent profile in real time to ensure Dragon’s entry into orbit for subsequent rendezvous and berthing with the ISS. This was achieved, and there was no effect on Dragon or the cargo resupply mission.”

    Amazing. One failure (maybe two?) that until recently would have been catastrophic and the system handled it and got the job done.

    @Checkmite – Do you just not like them because they are not a government agency? They had an unexpected failure in in the first stage and got the job done anyway. Has NASA ever done that? You should be more than impressed, not less than impressed.

    Yes, perhaps NASA would be more open about it, but I think it likely that NASA would be open about why they had lost a rocket and didn’t get the mission done at all. Wanting SpaceX to let you in on every step of their investigation into why a mission succeed despite worse than expected adversity is just silly.

    Try to see beyond your politics, SpaceX is not evil just because it’s a corporation.

  34. Robin

    @Checkmite (#39):

    Since SpaceX isn’t a government agency, their not bound to any transparency requirements that would benefit the public’s curiosity. Actually, as a private company and with the odd state of manned flight (including transport to the ISS of crew) and the competition for cargo missions to the ISS, SpaceX might be best served avoiding transparency. After all they don’t want to give anything away to their competitors, and as a new company doing business with NASA and possibly securing bigger things from NASA, they might be best served not saying anything until they’re sure what happened. Speculation by commentators and media can be dangerous, and those commentator(s) were SpaceX employees. I think it’s a good policy. I new by watching there had been an anomaly, and I was comfortable waiting to hear what had happened once SpaceX had determined the kind of anomaly, the effects, and how the system responded. Once they know what caused the anomaly, NASA will be informed as will the public.

    NASA has to be open because it answers, in part, to the public. After all, we pay for those missions and hardware. Don’t, however, think that NASA is completely transparent to the public when things go wrong. Nope.

  35. Charles Boyer

    @VinceRN “Amazing. One failure (maybe two?) that until recently would have been catastrophic and the system handled it and got the job done.”

    Vince, do you mean for SpaceX or in general? Several posts in this thread point out historical missions where similar events have occurred and the overall mission continued safely. SpaceX apparently designed and planned for the inevitability of engine loss from the beginning and yesterday their system worked as designed.

  36. Tall Blue Ape @ #24 said: “Wow. I’m a programmer, and I’m having a hard time fathoming how you would even come up with software so ass-kickingly responsive that it can near instantaneously recompute the required trajectory with the sudden new thrust available to it… no wonder it’s called ‘rocket science’!”

    Really? Remember, the Saturn V was able to do exactly the same thing 40+ years ago, including automatically adjusting its trajectory on the basis of engines lost mid-flight.

    I’m no rocket engineer or programmer, but I assume the software works on the basis of comparing where the rocket is now (speed, altitude and attitude) and where it wants to be at some point in the future (moving 27,000 km/h laterally and ~400 km up), and adjusts the rocket’s course to achieve its speed and altitude objectives. I have a strong suspicion that changes in the rocket’s thrust don’t come into it.

    As a rough analogy, I think it’d be like merging into heavy traffic: you see a gap in the traffic and automatically manipulate your car’s accelerator and steering wheel to enter that gap. At no time would you check your speedo to see how fast you were going, as all you need to know is how fast you’re going relative to the traffic you’re merging with.

  37. Monkey

    @Dan

    You, my friend, just made my day!

  38. Checkmite

    @ VinceRN: I understand this will tend to be a common reaction to criticism of a SpaceX mission; I’ve seen it argued in many places on the net over the course of reading about this incident. Rest assured I harbor no such prejudices over SpaceX being a private corporation or whatever. Last night, when I was fully under the impression that it was a completely flawless mission, I was posting and retweeting congratulations all around just as everyone else was.

    Drawing a comparison to NASA is simply logical and frankly inevitable, because NASA set the bar for this kind of operation.

    @ Robin: I was unaware until reading BA’s first blog entry that anything had gone wrong at all. I’ve just watched the local and national newscasts and all of them mentioned the launch but said nothing whatsoever about engines, shutdowns, fairings, or a second satellite.

    SpaceX may be a private company; but it is taking public money to carry government-owned cargo and supplies. Perhaps this means nothing after all; however, I propose that if it’s the case that SpaceX does not intend any kind of transparency about its activities, then offering a public commentated launch feed the way it does is somewhat dishonest. To avoid giving the wrong impression, I’m not saying I expect comprehensive data on every single aspect of the launch or any kind of anomaly. But I don’t think it’s “unreasonable” to ask if they’re going to provide a commentated public feed that they don’t use it to DISinform people about what’s happening. Don’t have some guy up there insisting everything’s gone perfectly when it hasn’t. There’s no reason an “engine out” has to be some kind of protected proprietary information that can’t be released publicly.

  39. Dave

    This was a success….payload delivered…..failover systems tested and proven….what’s the problem?

    As a potential suitor I wouldn’t look to this as a negative…”LOOK, we give you nine engines and we have proven we can survive with only 8″ That doesn’t even take into account their ability to deliver with 2 flame outs.

    Go SpaceX!

  40. Nigel Depledge

    Tall Blue Ape (24) said:

    Wow. I’m a programmer, and I’m having a hard time fathoming how you would even come up with software so ass-kickingly responsive that it can near instantaneously recompute the required trajectory with the sudden new thrust available to it… no wonder it’s called ‘rocket science’!

    It’s not as astonishing as you make it sound. Microsoft and Apple have, between them, got us all used to computers being rubbish. If you don’t use an OS, and don’t use clunky Intel system architecture, you can design a computer that can be fast and reliable. I do not know if this is what they did or not, but it seems to me to be a way to do it.

  41. Tony

    LOL at the various “…well I don’t know nuttin’ about programming, but I’m sure computers make that sort of stuff easy”.

    I assume @Peter B & @Nigel Depledge are in management.

  42. Tony

    Oh, I see @Peter B spend his life as a pen-pushing public servant. Figures.

  43. Martin Bonner

    @Tony (#48)
    I earn my living as a programmer, and have done for more than 30 years. (They’ve even stopped asking if I want to become a manager.)

    I would have expected computers to make that sort of stuff easy.

  44. khms

    I am a programmer (privately since 1978, professionally since 1991), and I don’t see anything astonishing about what the flight computer did. Maybe if this were 40 years ago …

    I’ve not seen the relevant formulas, but obviously they exist and are very well known by this time. So you write your software to apply them to your current speed and position, your needed speed and position, your maximum available thrust and remaining fuel, and feed the output to the engines. That is what control computers do, in the F9 just as in plants all over the planet. Or like an aircraft autopilot, for example.

    Control software isn’t exactly what I do, but I once had contact with control software for a cable confectioning machine (for cabling for cars). The “cut cable to length” part actually involved applied ballistics, because the transport was too fast to just use motor steps.

    For that matter, once upon a time I used to muck about with the Apple II floppy controller software, and the head movement there was also ballistic. The difference between loud and silent head movements was getting the ballistic timing correct.

    These two examples are fairly simple compared with the F9, but then I’m pretty sure the F9 isn’t programmed in assembler like these two were.

    But really – the math is known, just apply it.

    Now, given how fairly open SpaceX was in the past about problems, I wonder if their commenters simply didn’t actually know what had happened, because the relevant technicians were too busy to tell them. Which would also be bad, but for different reasons.

  45. @25. Paul :

    It should be pointed out that a Delta 4 launched last week also had a performance issue, but was also able to compensate and deliver the payload to the intended orbit. So robustness in the face of problems is not something unique to the Falcon 9.

    Hey, am I the only person here who remembers Apollo 13 – the movie that is not the launch which was before my birth! ;-)

    You see the Saturn V lost an engine in that mission too. (See wiki-link in my name for details.)

    Plus we hadApollo 12 surviving a lightning strike (or two!) and still delivering Richard Gordon into lunar orbit and Pete Conrad and Alan bean to the surface of the Moon.

  46. Cmdr. Awesome

    @48.
    I, too, am a proper professional programmer and have been for many years. Though not so long as Mr. Bonner, I fear.

    I, too, would have expected computers to make that sort of stuff easy.

    Real-time software (actual, honest to goodness real-time software, not whatever piece of schlock a marketing drone has decided to call “real time” when it has a response time measured in seconds instead of microseconds or faster) has been an object of intensive study in academia and in private sector for decades at this point. It should not at all be surprising that a system can detect an anomaly in a very short period of time and react to it, if it’s designed well – this is commonplace in modern real time systems.

    Note I am not trying to downplay the excellent work their engineers and systems developers have done by claiming it’s “trivial.” It’s just not as mind-boggling as some people suspect.

  47. Messier Tidy Upper

    Oops, just now seen :

    #36. Robin :

    In space flight, you’re never “bowling for dollars”, free from the worry of what could go wrong. This is only the Falcon 9′s fourth flight. You should note that the Apollo program had two engine out episodes in its first 13 flights, one of which saw 3 engines lose power.

    Hmm.. guess *you* – for one – do recall Apollo 13 and take it that’s one of those.

    Which are the others and which was the one with three engines down if you don’t mind me asking?

    @42. Robin :

    Don’t, however, think that NASA is completely transparent to the public when things go wrong. Nope.

    I guess its pretty obvious that there are varying levels of opaquity and transparency and while NASA may be less opaque than Space X it still wouldn’t be 100% transparent.

    @17. TxSkeptic :

    The wiki on the Falcon 9 says SpaceX plans eventually recovering & possible reuse of 1st and 2nd stages, but has not recovered any to date, and didn’t think it would happen until flight 6. (this is 4) Maybe this is a good one to go after for failure analysis.

    (& seconded by #23. Wzrd1 .)

    Could well be wrong but I’m guessing that such recovery could only happen *if* it had been planned for in advance and thus equipped for recovery (eg. by fitting parachutes as done on the Space Shuttle’s Solid Rocket Boosters) and that on this specific flight the rocket stage in question simply burnt up /crash-landed (quite probably in the ocean) and would be very difficult to retrieve.

    Perhaps not absolutely impossible tho’ .. but doubtful if we can /will recover the stage and do a physical post-mortem on the machinery as opposed to a telemetry / visual /numerical analysis of the issue.

  48. Robin

    @Messier (#54):

    Apollo 6, the last Apollo test flight, lost 3 engines in one stage (the second stage if I remember correctly).

    @Stephanie (#38):

    According to SpaceX, that debris you saw was made up of fairing pieces, not engine pieces. If that is the case and assuming that the engine anomaly that preceded the fairing failure wasn’t such that it would of damaged other engines, a shut down of #5 would not have caused the dramatic fairing failure you saw as there is no fairing anywhere near #5. The fairings would not have been subjected to the pressure changes seen by the faring in this incident since #5 is shielded from the fairing by the other engines’ exhaust.

  49. TheBlackCat

    Also a programmer here. It isn’t like they would necessarily even have to code for every given possible failure, it would just need to be able to figure out what the necessary engine firing profile is needed to achieve a goal given the engines available and the current conditions (along with some if-tests to change the goal if the original goal cannot be achieved, as it did here by not placing the satellite).

    As long as the formulas needed to calculate the result for all the engines are available, it should be possible to apply them to fewer engines, and bounds checking is not that hard (no matter how much Oracle wants us to believe otherwise).

  50. Tony @ #48 said: “LOL at the various “…well I don’t know nuttin’ about programming, but I’m sure computers make that sort of stuff easy”. I assume @Peter B & @Nigel Depledge are in management.”

    No I’m not. I’ve done programming in my time (although many years ago), so the concept of writing code to achieve an objective isn’t completely unfamiliar to me. More usefully, though, I’ve learned a lot about how rockets are controlled from reading comments made by Jay Windley at the ApolloHoax forum.

    Tony @ #49 said: “Oh, I see @Peter B spend his life as a pen-pushing public servant. Figures.”

    Why does previously being a public servant prevent me from learning things like how to control rockets? For one thing, it taught me how to undertake research.

  51. Checkmite

    I’m not a programmer and have no idea how easy or difficult it would be to code a computer to compensate for engine loss in flight. I was under the impression that it’s something contemporary multi-engine rockets today are capable of; so Falcon’s demonstrated ability to do so would certainly prove it to be a fully-modern state-of-the-technology vehicle.

  52. Nigel Depledge

    @ Tony (48) -
    I’m a biochemist working in the biopharmaceuticals sector.

  53. TheBlackCat

    @ Checkmite: It isn’t just rockets, either. Most modern fighter aircraft are essentially fully computer-controlled, the pilot just tells the computer what it wants the plane to do and the computer figures out how to do it. Such aircraft are fundamentally impossible for a human to fly (our nervous system is not fast enough), so the computer has to be able to cope with any sort of failure, even under combat conditions.

  54. Messier Tidy Upper

    @55. Robin : @Messier (#54) : Apollo 6, the last Apollo test flight, lost 3 engines in one stage (the second stage if I remember correctly).

    Cheers for that. Much appreciated. :-)

  55. Ferris Valyn

    A few things worth noting – NASA currently does NOT have any of its own rockets. The only “NASA rocket” for the last few years was Shuttle.

    (To Checkmate in particular)
    Regarding getting info – SpaceX has actually provided a lot more info than historically happened, with vehicles like the Titan IV and so forth. And, again, those were NOT NASA vehicles.

    Further, there is the question of WHO needs to have the access to transparency. Ultimately, it is NASA that needs transparancy, since they are, for lack of a better phrase, providing the payloads. But they are being told data that is proprietary (and it is important to rememebr that SpaceX is not the only game in town – This is an industry, and they are competing with companies like ULA and their Altas V and Delta IV vehicles). But they have a lot of insight into the vehicle.

    Does that make sense?

  56. Bill Nettles

    Nice cover story on the ORBCOMM satellite. The conspiracy channels are buzzing about the new corporate spy satellite that just went into orbit. :) (not really…)

  57. TheBlackCat

    @ Bill Nettles: SHHHHH!!!!! Don’t give them any ideas.

  58. Charles Boyer

    @Robin: “Apollo 6, the last Apollo test flight, lost 3 engines in one stage (the second stage if I remember correctly).”

    No, it was two. See post #10, which I culled together from the mission report.

  59. Charles Boyer

    2 Messier Tidy Upper – LOL, I remember Apollo 13′s launch pretty well. I saw it in person, as I did every Saturn V that ever flew. It was nice living in Cocoa Beach, FL as a kid and having family members who worked at the Space Center…. :)

  60. Paul

    Plus we hadApollo 12 surviving a lightning strike (or two!) and still delivering Richard Gordon into lunar orbit and Pete Conrad and Alan bean to the surface of the Moon.

    That was perhaps one of the finest moments of the ground controllers at NASA, a demonstration of what the “steely eyed missile men” could do under pressure. EECOM John Aaron recognized the bizarre telemetry and directed the astronauts: “Flight, try SCE to ‘Aux’”, a command so obscure only one of the astronauts knew what he was talking about. But it did the trick.

  61. Robin

    @ Charles Boyer (#66): Apparently my source had it wrong. Thanks.

  62. Checkmite

    @ Ferris Valyn: and yet, when pressed, evidently SpaceX was comfortable releasing the fact that there was an engine out, that the computer was able to compensate, and that certain parts of the rocket fell off for such-and-such a reason. That tells me these things aren’t considered proprietary secrets – although to be honest I can’t think of why they would be; these are things that just happen to rockets now and then.

    I think I was expressing this adequately earlier; but in case I wasn’t: if SpaceX decides it doesn’t want to be publicly-interactive and that it wants its launches to be more like Air Force launches, that’s fine. The Air Force is pretty closed-lipped about its launches outside of announcing the launch schedule and reporting serious failures (if nothing unusual happens, they usually don’t release statements about how well the launch went or whatnot). I’m OK with that, and I would be OK is SpaceX chooses to be that way.

    What I don’t like is the appearance that SpaceX wants it both ways. They appear to want to engage the public, and hold press conferences beforehand. They create publicity. They offer a public commentated launch feed. They issue press statements. But at the same time, they wish to conceal problems and suddenly clam up when they happen. I realize they’ve got competition; but I don’t buy that as the reason for what they did. If hiding proprietary data from the competition was a concern, why telecast the launch and controller communications like that? Why call out telemetry and flight parameters on a public feed? Why would none of this information be proprietary but the fact there was an engine-out would be? It seems far more likely to me that the decision to pretend certain things weren’t happening wasn’t to keep proprietary data from the competition, but merely to keep themselves from possibly looking bad if the situation got worse. I can’t support that way of doing things.

  63. Ferris Valyn

    I am sorry, but huh?

    First Publicly released data is never proprietary. And none of what you stated is proprietary. Because its all observable in public. Stuff was seen falling from the engine region during launch. The Dragon made it to orbit. SpaceX had released the launch profile, and the actual separation was different from the publically released data.

    In short, they are providing an explanation of publicly available data.

    Frankly, that I find quite reasonable, and its actually a point of discussion regarding commercial spaceflight – when you have an incident on a flight, should that be proprietary?

    Second, I feel like you are complaining that it didn’t happen in real time. And I am sorry, but they were launching a rocket. In the after launch presser, they gave all the details they were sure of. Go back and look at the first Falcon 1 launch, and the investigation, or the second Falcon 2 launch and investigation – they’ve been open.

    In short, that is being open, at least to me.

  64. Checkmite

    Certainly live launch video commentators aren’t busy launching a rocket; their job presumably is to commentate on what’s happening. This is part of the reason I brought up NASA’s late performance when it came to rocket launches; the commentators during those launches didn’t seem to have a problem explaining developments; take for instance the Glory mission (watch at http://www.youtube.com/watch?v=8BFAxZflkW0 beginning at about 5:00). This makes me skeptical that “they’re busy launching a rocket” is an acceptable explanation for why any hint of the Falcon 9 issue was omitted from the launch coverage. Note that the Glory failure was not announced “instantly” or “realtime” either; but it happened during the launch and so was announced during the launch feed.

    I did not see any after-launch press conference by SpaceX, unless you are referring to the short statement they gave about the engine not exploding (which I was under the impression wasn’t a scheduled press statement but a response to a general request for information by third parties). If there are any links I would be eager to read them to see if I’m misinterpreting the events as I saw them.

  65. jfb

    SpaceX has built and flown in the neighborhood of 40 Merlin 1C”s now, and this is the first one that appears to have failed catastrophically. If it’s a design problem, it’s a pretty subtle one. I’m going to put money on a manufacturing flaw that wasn’t caught on the test stand (I can imagine there have been some long and intense meetings in Hawthorne and McGregor over the last couple of days).

    There are two more flights with the 1Cs (I think), then they switch over to the 1Ds which are supposedly lighter and simpler, so there’s (hopefully) less chance of an issue with them.

    Engine failures are never good news, but they are also inevitable; you’re operating at the edge of all kinds of margins. At least we now know that SpaceX’s claims of engine-out capability aren’t just hype (for at least one failure mode, anyway), although this probably wasn’t the best moment to have that tested. And it did screw Orbcomm, but as a secondary payload they should be willing to tolerate a higher risk.

    So far, the primary mission is successful; Dragon is in the right orbit and is on track to berth with the ISS. So on balance this is good news. Still, SpaceX needs to figure out exactly why the engine shredded itself and make sure it doesn’t happen with the remaining 1Cs and any 1Ds, ideally before the next flight.

    Speaking as a code monkey, I’m impressed by the software too, but that’s mainly because I’ve done very little serious realtime or avionics work. The code itself is probably quite simple compared to most desktop applications, but has to meet some very strict requirements for performance and fault tolerance; that’s what makes the work so difficult. You can bet these guys know their hardware inside and out.

  66. Chris

    Having a good laugh at the programmers on here who think that correcting for a failed rocket is just a matter of putting numbers into a few formulas. It’s not called rocket science for nothing. No doubt John Carmack, a better programmer than most and programmer of Doom1/2, Quake 1/2/3/4 and lead engineer of Armadillo Aerospace, would have something to say to those people.

  67. Ferris Valyn

    Checkmate –

    Go to http://www.youtube.com/watch?v=Fi-M3VrCXCc to see the after launch press conference. Gwynn Shotwell talks about it at roughly 3:45 or so. And this press conference happened very shortly after launch.

    jfb – It was NASA who said don’t do the re-light, not SpaceX

  68. Tom

    @Chris (comment #73): If rocket control is not a matter of putting numbers into formulas, then what is it? Ultimately, it’s a trajectory problem — the sort of problem that digital computers were *made* to handle. (For example, ENIAC was designed to compute ballistics tables.)

    And what’s with this disdain towards programmers? After all, it was IBM that designed the Saturn V guidance computer. And what do you call the people who wrote the Falcon 9 guidance code? Not programmers?

    To handle an engine-out situation, you’d first gimble the engines to compensate for the unbalanced thrust vector. Then, it’s just a matter of computing a new trajectory to orbit — one with a different ascent profile, longer burn time and higher overall fuel consumption.

  69. Messier Tidy Upper

    @67. Charles Boyer :

    Messier Tidy Upper – LOL, I remember Apollo 13′s launch pretty well. I saw it in person, as I did every Saturn V that ever flew. It was nice living in Cocoa Beach, FL as a kid and having family members who worked at the Space Center….

    Ah some people have all the luck, you lucky ..! (Envious sigh.)

    Oh well. Do you happen to recall when /if you were told by NASA / Apollo launch commentators of engine failures and other problems at the time for comparison porpoises?

  70. Bater

    I’ve never understood this (even from the time when the Saturn V had a similar problem) – if the rocket can function without one of its engines then why was it designed with it in the first place? Just in order to have some redundancy when an engine shuts down? Wouldn’t the rocket be able to carry additional payload if they removed the “extra” engine?

    Bater

  71. jfb

    @Valyn:

    It was NASA who said don’t do the re-light, not SpaceX

    My interpretation of events is that the second stage had to make up for some delta-V lost by the first stage after the engine shutdown, which is why it didn’t have enough propellant to meet NASA’s safety margins.

    If anyone has a link to a statement claiming otherwise, I’d be glad to see it.

    @Chris:

    I take it you’re speaking from experience. Care to share with us other code monkeys exactly what is involved with writing rocket guidance and control software? I’ll admit I haven’t done any real embedded or avionics work, and very little realtime work, so I’m sure there are issues I’m not aware of. But I’m also pretty sure that, compared to most desktop systems, the code is relatively straightforward, at least in terms of overall design. The hard bit is meeting the performance and fault-tolerance requirements, and just slogging through the process.

  72. Paul

    I’m not surprised that this happened. Happens pretty frequently. Rocketry is such a complex science with so many different points of failure (and a relatively high rate of failure), that no matter how well you prepare, no matter how much work you put into it, it might as well be voodoo. “The cause of the engine failure was, well, we didn’t sacrifice enough chickens to the god of explosions and awesomeness. We’ve learned from this grievous miscalculation and won’t be repeating it.”

    I’m sure one of the virtues of having nine stage 1 engines is that losing one isn’t a huge deal. Didn’t Apollo 13 lose its stage 1 center engine in flight? As I recall, the word from mission control was “meh, we’ll just burn the others for a bit longer.” I imagine this is also a failure that NASA insisted SpaceX to be able to cope with before they’d release cargo to fly with them.

    On a more PR side, I’m also not really surprised that this wasn’t really announced over the net that we heard. If it’s no big deal, then there’s no reason to use scary phrases like “engine out/cutoff/shutdown” or “We’ve lost pressure in the engine” or “abnormal condition” or whatever phrase they use on the net that the entire world is watching. That was probably announced to the flight conductor on a closed net. Put yourself in a customer’s shoes. You’re not a rocket scientist or an afficionado of all things space, you’re a businessman. Are you really going to contract your multi-million dollar satellite (or whatever) launch to a company that LOST AN ENGINE IN FLIGHT? OMG, OUR SATELLITE IS GONNA CRASH AND BURN AND WE’RE GONNA BE OUT MILLIONS!

    “Yeah, let’s just keep that stuff to ourselves for now.”

  73. jfb

    Turns out I was wrong (no big surprise there); the issue with the second stage was not propellant, but approach. From Ars Technica:

    Unfortunately, the engine malfunction placed the Falcon 9 upper stage in a slightly different approach to the International Space Station. That new approach caused the stage to violate a set of conditions known as a “safety gate”; there was no way the satellite could ascend to its intended 350km x 750km orbit without crossing the ISS orbit, and no time to check to make sure that no collision would occur. The second stage’s flight control software automatically cancelled its second burn, leaving the satellite in a much lower (203km x 323km) orbit than intended. Engineers from Orbcomm and Sierra Nevada Corporation, the manufacturer, are deciding what can be done, and both SpaceX and Orbcomm are being noticeably cagey about their press releases.

    As a secondary payload, Orbcomm was exposed to more risk; hopefully that was reflected in the contract and the pricing.

  74. TheBlackCat

    @ jfb: “As a secondary payload, Orbcomm was exposed to more risk; hopefully that was reflected in the contract and the pricing”

    I think it was also reflected in the fact that it was a test satellite, not the fully-equipped model they will send up later.

  75. Bater asked: “I’ve never understood this (even from the time when the Saturn V had a similar problem) – if the rocket can function without one of its engines then why was it designed with it in the first place? Just in order to have some redundancy when an engine shuts down? Wouldn’t the rocket be able to carry additional payload if they removed the “extra” engine?”

    Yes, the Saturn V could and Falcon 9 can operate after losing engines, but not always.

    What it boils down to is fuel efficiency – for a given amount of fuel, the greater the thrust, the further you go. Remove an engine and you’ll get proportionately less use from the fuel.

    A rocket’s acceleration is calculated by dividing thrust by mass. If the result is greater than 1, the rocket can accelerate, and the higher it is the faster it accelerates. If the number is less than 1, the rocket slows down.

    If the rocket loses an engine, its thrust is reduced (by 1/5 in the case of the Saturn V 1st or 2nd stages, or by 1/9 in the case of the Flacon 9 first stage). But mass isn’t reduced. This means acceleration is reduced. That is, lose an engine and the rocket accelerates more slowly.

    (Another factor to consider is that as a rocket uses up fuel, it gets lighter. This means that even with the thrust remaining the same, the rocket’s acceleration increases while the engines are burning that fuel. So the number we’ve calculated above is constantly changing.)

    In the case of the Saturn V, at launch its thrust was about 7,500,000 pounds, while the mass was about 6,200,000 pounds. Divide the first by the second, and the result is about 1.2. This is not much above 1, and means that the Saturn V initially accelerated very slowly. This is why it took so long to clear the launch tower. Now consider what would happen if we removed one of the five engines on the Saturn V: thrust would reduce by 1/5 to 6,000,000 pounds. Divide this by the mass of 6,200,000 pounds and the result is less than 1. In other words, the Saturn V could not lift off if it only had four engines. In fact, the Saturn V didn’t get its engine-out ability until about 20 seconds into the flight – by which time it had burned enough fuel to lighten the load.

    To take your question more generally, if the rocket can operate without one engine, why not take it out, let’s go back to the calculation of dividing thrust by mass. If that result is just over 1, the rocket accelerates very slowly, while if the number is higher, the acceleration is higher.

    Consider an imaginary rocket with a thrust to mass ratio barely above 1. That rocket is going to accelerate very slowly, and take hours to reach orbit. Burning the engines for hours is going to take huge amounts of fuel.

    Now consider another imaginary rocket with a thrust to mass ratio of, say, 10. That rocket is going to shoot up into the sky, and reach orbit in under 10 minutes. That’s going to take a lot less fuel than the previous example.

    Go to http://phet.colorado.edu/sims/lunar-lander/lunar-lander_en.html to try out its lunar landing simulator. Once you’re familiar with it, try this experiment. Burn the lander’s fuel until you have only 50 kilograms left, with the lander sitting on the Moon. Then set thrust to maximum and see how high you reach (I made it to 110 metres). Reset and again burn the fuel down to 50 kilograms, with the lander sitting on the Moon. Now set the thrust to the lowest possible that actually lets the lander lift off, and see how high you reach this time (I made it to 3 metres). What this experiment shows is that the higher the thrust for a fixed amount of fuel, the greater the distance you travel.

    So why aren’t all rockets given super acceleration like the second example? The main reason is to minimise stress on the payload. The payload (satellite or whatever) may be damaged by high acceleration. Lower acceleration places less stress on the payload. As launch into orbit is a one-off stress in the satellite’s life, it makes more sense to reduce the launch stress than to over-engineer the satellite for an event which represents so little of its working life.

    So the design of rockets and payloads for each other is a balancing act: too little thrust and you need more fuel; too much thrust and you might damage the payload.

  76. jfb

    Peter B @ 83:

    So why aren’t all rockets given super acceleration like the second example? The main reason is to minimise stress on the payload. The payload (satellite or whatever) may be damaged by high acceleration.

    In fact, the rocket has to throttle down (reduce thrust) once the propellant mass gets below a certain level to keep the payload from being crushed by the acceleration, and I think the F9 actually shuts down two engines near the top of the climb for this reason.

    Although I think the story will be slightly different with the V1.1 F9; the Merlin 1Ds are supposed to have a greater throttle range than the 1Cs if I remember correctly.

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