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SpaceX Launch Not So Perfect After All

Posted by samzenpus on from the we-have-a-problem dept.

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.'"

15 of 272 comments (clear)

  1. An by JustOK · · Score: 5, Funny

    An anomaly? That's strange.

    --
    rewriting history since 2109
    1. Re:An by the+gnat · · Score: 5, Insightful

      Libertarians rode the back of this and shouted about how much better it would be to privatise space. But in fact we're just right (*) here again, with SpaceX substituted for Boeing.

      I think you'll find it's not just libertarians cheering for this - after all, privatizing the launch infrastructure has been a key element of Obama's space plans. The difference from the previous situation, where NASA relied on bloated defense contractors, is that SpaceX and its competitors will have to enter fixed-price bids, instead of the old cost-plus contracts which gave the contractors zero incentive for efficiency. Whether this will actually work in the long run remains to be seen, but it's hard to see how this is worse than the old system, and putting the federal government into the launch vehicle business sounds like a spectacularly awful idea.

    2. Re:An by Anonymous Coward · · Score: 5, Interesting

      The reason why you can have a fixed price contract in this situation is that NASA isn't really defining any requirements; also not changing them midstream; but also that there is little development risk. The rocket from SpaceX isn't really anything innovative, which is actually a good thing, not a bad thing.

      Where fixed price contracts don't work is when you have a significant amount of development risk, and you end up having to build that into the cost of the contract, meaning that you often don't end up with low price bids. Europe's ESA for example pretty much only works from Fixed Price contracts, which builds in the cost of that risk into the project, inflating the bid cost, and you end up with Europe overall, not really committing to many projects, because they get sticker shock.

      Who can say which method is better overall.

  2. Whats the problem? by ZiakII · · Score: 5, Informative

    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.

    1. Re:Whats the problem? by residieu · · Score: 5, Insightful

      Just because you have a backup plan, and it works, doesn't mean the launch was perfect.

    2. Re:Whats the problem? by jamstar7 · · Score: 5, Informative

      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.

      IIRC, there was no way to recompute a Saturn 5 flight profile on the fly. Remember, kids, that was back in the days when we hunted dinosaurs from the backs of our '57 Chevys. Kudos to SpaceX for having enough out of the box thinking to have the needed software routines in the can already and ready to go. Falcon 9 is more than just another Big Dumb Booster, AAMOF, from everything I'm reading and seeing of its operation, it's pretty goddamned smart. Remember the test flight to the ISS? The first launch attempt, the onboard computers detected a glitch that might have taken out the bird and shut down and aborted the launch right at T -0, even after the humans tapped the buttons authorising the computers to do the launch. Like I say, some serious onboard smarts programmed by some seriously smart people.

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      Understanding the scope of the problem is the first step on the path to true panic.
    3. Re:Whats the problem? by fyngyrz · · Score: 5, Informative

      No, the engine did not explode. The fairing around the nozzle was crush by the sudden loss of interior pressure when the engine shut down -- the external pressure was then much higher than the nozzle's interior pressure (no more rocket exhaust) and it got crushed and fell away, harming nothing. The engine is still there, intact, and it did, in fact, just turn off.

      --
      I've fallen off your lawn, and I can't get up.
    4. Re:Whats the problem? by rickb928 · · Score: 5, Insightful

      If that's accurate, then SpaceX is looking into a shutdown event, a LOT different than a destructive failure. The fairing imploding will either be the anticipated result, or a new issue to understand and resolve/document.

      Shutdown may be accompanied by data, and there is a fix. Valves, pumps, all kinds of fairly well understood stuff to analyze and resolve. Destructive catastrophic failure would be much more disturbing.

      So far, they seem to be doing at least as well as NASA did in the early days. Mercury was a real crap shoot, and early Saturn development was exciting to say the least. I filled a few scrapbooks with notes on those faiures. Fun times...

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      deleting the extra space after periods so i can stay relevant, yeah.
    5. Re:Whats the problem? by shutdown+-p+now · · Score: 5, Funny

      Shooting yourself in the foot is, none the less, not exactly what you're supposed to do.

      I'm a C++ developer, you insensitive clod!

  3. not really a bad thing by wierd_w · · Score: 5, Insightful

    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.

  4. It was a good launch by Maximum+Prophet · · Score: 5, Insightful

    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.

    --
    All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
    1. Re:It was a good launch by TWX · · Score: 5, Insightful

      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.

      --
      Do not look into laser with remaining eye.
    2. Re:It was a good launch by Electricity+Likes+Me · · Score: 5, Insightful

      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.

  5. 9 engines. All together now! by Fuzzums · · Score: 5, Funny

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

    --
    Privacy is terrorism.
  6. A statistical analysis: by mosb1000 · · Score: 5, Insightful

    They've launched 4 Falcon 9 rockets. One engine has failed, so that's an observed failure rate of 1/36 or about 3%. The means the odds of 0 or 1 engine failing (a successful launch) is 97.6% and the odds of more than one failing is 2.4% assuming the currently observed rate is representative of the actual rate. 2.4% would be an excellent failure rate for any rocket launch system. In fact, no one has achieved a failure rate that low. And bear in mind this rate includes 3 experimental launches and only one production launch. Of course, a launch failure can be brought about by more than just engine failures, so 2.4% is really a minimum and other factors which haven't yet manifested themselves would add to it.

    Space X is saying that this is probably a failure in the aerodynamic structure of the rocket, not the rocket engine itself. If that's the case, the above statistical analysis is invalid because it assumes no interdependency in engine failures. A structural failure could lead to more than one engine failing. It would also be problematic in assessing the future failure rate because the engine configuration is going to change in their 1.1 version. The outer engines will be circularly arranged in future versions while in current versions they're arranged in a square.