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SpaceX Launch Not So Perfect After All
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.'"
Just because you have a backup plan, and it works, doesn't mean the launch was perfect.
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.
The fact that the rocket had enough redundancy built in doesn't mean that the cause of the failure should not be investigated.
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)
Who is saying it shouldn't be investigated? Every launch should be measured and checked.
If you can recover the engines, the unburned parts tell you where they're too heavy, and the burnt through parts tell you where you need more strength.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
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.
From what can be read between the lines, the engine didn't explode but rather imploded. It shut off at "maximum dynamic pressure", sometimes called simply "Max-Q", when the atmospheric pressure pushing against the vehicle due to its velocity is at the highest it can be at that point in the flight. Between the pressure from outside of the spacecraft and from the nearby engines, the nozzle apparently collapsed in on itself and tore loose, hence the debris.
The engine itself was still there, just missing the nozzle. That is why data was continuing to be sent from the engine and respond to system queries about its status. Had it exploded, those sensors and microcontrollers running the engine would not be in place.
Technically you are correct that all that could be said from the telemetry is that the sensors were still in place, but those sensors would not be registering if it was an outright explosion.
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...
deleting the extra space after periods so i can stay relevant, yeah.
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.
First, what's the cost per unit of payload mass?
Second, what's the value in being able to send up smaller missions, akin to a commuter flight versus a jumbo jet?
Third, what's the redundancy of having multiple functional launch systems worth?
Fourth, what's the value in the US having a launch system of its own without depending on other countries?
Fifth, what's the likelihood that having this launch system prove to be successful will result in the developer working on heavier-lift systems?
When the United States has no launch system we are completely dependent on the Russians for access to a very expensive machine built with enormous cost to us and to all of the other participating countries. Should the Russians decide that they don't want to play anymore, they could simply deny our astronauts access, making the station de facto Russian property. Since the Russians have significantly more station experience than we do, I'm sure that they'd be able to operate it without us.
Our having a launch system, ultimately intended to be man-rated, essentially prohibits that possibility. Same with the Europeans, if they ever have a man-rated rocket. I'm all for that.
Do not look into laser with remaining eye.
What I don't like is the fact that space is becoming increasingly privatised.
Well, why shouldn't it be? Most endeavors in the US are handled privately.
Then Musk came along and said, "Hey, I've got rich from founding the world's worst consumer bank, how about I give you the first few hits for free?" and hired a few experienced people.
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.
And a considerably cheaper launch vehicle compared to the Delta IV (which Boeing put in the United Launch Alliance rather than continue to fly it themselves). I can't argue with results.
Maybe he doesn't really have them and is bullshitting. People do that a lot.