10
$\begingroup$

From the raw video of the event (which just happened), a trained eye can narrow the possibilities, given good general knowledge of the rocket. What in the video indicates which systems were involved, what kind of failure occurred, and how the failure progressed?

I know that proper analysis will follow, but what should one look at in the video as definite information as to the nature of this event?

Edit: Here is the video released by NASA

And a second angle including a fair bit of close-up footage, although it misses some key seconds. (It is a large group of reporters filming from nearby, and members of the public, and includes a lot of personal reactions).

$\endgroup$
  • 3
    $\begingroup$ I'm not particularly trained, but it looks like there's a brief flash at the base of the rocket prior to the larger fireball. I'd guess one of the two rocket engines failed catastrophically, and that relatively small explosion ruptured the fuel tanks, releasing a lot of kerosene and LOX. I don't know if you're looking for a more detailed guess than that :) $\endgroup$ – Russell Borogove Oct 29 '14 at 0:10
  • 1
    $\begingroup$ Fuel tanks themselves don't usually have catastrophic problems. A ruptured fuel line would probably lead to an engine shutdown -- I don't know about Antares specifically, but rockets are usually set up to shut down the engines quickly when things go wrong, so you don't continue powered flight in an uncontrollable direction. $\endgroup$ – Russell Borogove Oct 29 '14 at 0:29
  • 1
    $\begingroup$ Is stackexchange really the place to speculate about this? This question and any answers based on just a video will have no long-term value, since what happened will be resolved with far more data and a report will be issued. $\endgroup$ – Mark Adler Oct 29 '14 at 3:25
  • 4
    $\begingroup$ I would suggest emphasizing the part about "what should one look at" and rewriting the title to reflect that. If the question focused on that, then I'd say it's fine and not speculative at all. But the title still suggests it's asking us to draw conclusions based on limited data we have available (basically video of it from a few angles, launch timeline and some of the flight profile that was shared to the public). Perhaps asking more directly about flight anomaly investigation techniques and the role of video footage in it wouldn't go amiss either. $\endgroup$ – TildalWave Oct 29 '14 at 6:31
  • 4
    $\begingroup$ The N-1 strikes back from the grave. $\endgroup$ – Deer Hunter Oct 29 '14 at 8:16
5
$\begingroup$

I'll just start with some things that came to my mind. Not planning to provide a complete list here.

You can look at the craft itself prior to and shortly after launch. Was there any leakage or jets of propellant where there shouldn't be any? For example, smoke was visible during the final launch of the space shuttle Challenger.

Comparing the video to a previous launch we find no obvious leakage. However, the night launch makes it difficult to see much of the vehicle at all.

The next thing that came to my mind was the guidance system failing and causing automatic self-destruction, a bit like on that recent Proton launch. The rocket does sway to the side a bit after launch, but that may be on purpose, in order not to recontact the launch tower. It does the same in the other video.

Now, I'm going out on limb and speculate a bit from the poor footage available. The flame in of the exhaust turns from yellow-blue to bright yellow a split second before the explosion. One explanation (not the only explanation) for this would be a failure in the oxygen supply, so the rocket quickly goes to extremely fuel-rich combustion.

However the oxygen pump of the NK-33 is on the same shaft as the fuel pump, and located between the turbine and the fuel pump. So the fuel pump can't keep working when the oxygen pump has stopped (or exploded).

Now it would be interesting to have a high-res video from another perspective to see if both engines fail simultaneously. If they do, my oracle is this: There was loss of pressure on the oxygen tank or an obstruction in the ducts. This caused the combustion to go extremely fuel rich for a split second, until the dry-running turbo-pump bearings (which must be cooled with liquid oxygen) overheated. This ignited the metal of the pump housing, leading to the rest of all this unpleasantness.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.