It has quite a roll oscillation compared to what we're used to in these videos. Funny stage wiplash. Now Elon Musk knows why NASA waits such a long time between MECO & ET separation.

That is bizarre at the end of the video. It looked at least six inches away then snap back.

I wonder if they capture all this data and store it into a database. Then break out the 3d simulation. That would be pretty cool.

More armchair rocket science ideas. It appears like once the stage separates maybe the pressure within the separated stage increases because its exposed to the atmosphere. Maybe, this pushed the fuel out at a faster rate and gave it a little pop forward? Or maybe the stage had less pressure inside and before the upper stage could fire it sucked both stages back together? Hmm, if the upper stages fires a little sooner it will force it all away. *I've got no idea how this really works! (disclaimer)

Well, that oscillation just does not look right. That has got to be a separate problem happening. Though, benign. Don't see that much rocking on a shuttle video but this is a smaller rocket.

That is a real don't let the door hit you in the rear end moment.

I'm a subscriber to the SpaceX mailing list. This is what I got on Wednesday:



------


Aug 6, 2008 10:20 PM
subject Message from Elon Musk: Falcon 1, Flight 3 Mission Summary



*Timing is Everything*



On August 2 nd, Falcon 1 executed a picture perfect first stage flight, ultimately reaching an altitude of 217 km, but encountered a problem just after stage separation that prevented the second stage from reaching orbit. At this point, we are certain as to the origin of the problem. Four methods of analysis – vehicle inertial measurement, chamber pressure, onboard video and a simple physics free body calculation – all give the same answer.



The problem arose due to the longer thrust decay transient of our new Merlin 1C regeneratively cooled engine, as compared to the prior flight that used our old Merlin 1A ablatively cooled engine. Unlike the ablative engine, the regen engine had unburned fuel in the cooling channels and manifold that combined with a small amount of residual oxygen to produce a small thrust that was just enough to overcome the stage separation pusher impulse.



We were aware of and had allowed for a thrust transient, but did not expect it to last that long. As it turned out, a very small increase in the time between commanding main engine shutdown and stage separation would have been enough to save the mission.



The question then is why didn't we catch this issue? Unfortunately, the engine chamber pressure is so low for this transient thrust -- only about 10 psi -- that it barely registered on our ground test stand in Texas where ambient pressure is 14.5 psi. However, in vacuum that 10 psi chamber pressure produced enough thrust to cause the first stage to recontact the second stage.



It looks like we may have flight four on the launch pad as soon as next month. The long gap between flight two and three was mainly due to the Merlin 1C regen engine development, but there are no technology upgrades between flight three and four.


-------------



Terry again: Poor blokes must be pretty embarrassed. The nozzle hit the interstage on flight #2 and contributed to its problem (although the main problem: guidance cycle coupled with a slosh mode...Delta III #259 died from a similar problem...probably would have happened without the post-separation contact.) To get caught by residual thrust must be really frustrating. I'm pretty sure the problems of both #2 and #3 could have been defeated by pre-flight analysis if someone had the foresight to see the possibility of their occurrence.

I don't know if they have 2 video downlinks and spliced it together or what. I suspect some video has still been cut out.

It looks to me as though when the first stage hit the second stage and the second stage ignited, that the interaction caused the upper stage to spin head over heals. I think we're missing some video, perhaps intentionally, that shows this. The video then shows the shroud coming off and in a few frames we see the earth which is probably not normal. As a result of the spinning, the shroud probably hit the rocket and who knows what else.

While I'm glad they released this video, it's unfortunate that the live feed was cut and that the whole video has not been released. I guess we can't file a FOI request against them, huh?

The "shroud" you speak of is the payload fairing which was surrounding the satellite. This separation is perfectly normal. You want to shed its extra weight shortly after stage separation.

"This separation is perfectly normal."

When the fairing separates, the rocket is not supposed to be pointing towards the earth. This separation is not normal. Check out the last launch video for the rocket.

SpaceX is not as open as advertised. The "live" downlink distribution terminated prior to the incident. Either they had telemetry told them there was a problem and they stopped it or they were on about a long second delay and stopped it before the public could see the problem. I was watching the "live feed and remember it stopping at about +2:20 - well before MECO. The obvious attitude problen during fairing sep also need to be addressed.

Bottom line - a private company has the right to keeping its data private. That is OK. What is not OK is to withhold and spin it in order to manipulate its stakeholders, customers, and the public that has blindly supported SpaceX in the past.

Editor's note: They have real ITAR concerns. What they are doing could be used to teach the bad guys how to build - or not build - their ICBMs.