FAILURE: Sea Launch - Intelsat 27 - February 1, 2013 (0656UTC)

[sdsds]

Antares you forgot Fuel Dome Implosion

I really would like to see some solid details released on the real cause...

I found Kim Keller's earlier post regarding a possible ULA/Atlas response quite intriguing:

Maybe not stand down, too early to say. But they will be tracking the failure analysis as closely as they can until separation between the -170 and the -180 is established.

So even if solid details aren't released (to us) anytime soon, we might be able to infer something based on how ULA behaves. They might have  better sources of information than we do!

[bjornl]

Don't know if anyone finds this interesting, but I put the earlier Intelsat launch side-by-side to this launch with youtube doubler: http://youtubedoubler.com/6KZU

[iamlucky13]

Does [winds: 6 knots & seas: 6.5’] qualify as “rough sea” ??
6 knots translates into 3.1 m/sec – it’s almost nothing, as I understand – am I right?
seas: 6.5’ – 2 meter waves; can they make an ocean oil rig “unstable” ??

As a 20 year US Navy vet, I will state unequivocably that 6 knot winds and 6.5ft seas are nothing to a vessel the size of the Odyssey platform, particularly when it is ballasted down for launch.  In addition, such platforms usually have some form of active stabilisation.

Absolutely. The parent platform of Odyssey was designed to hold a drill string in the Barents and North Sea during winter storms.

A drill string, of course, is not a rocket. Much more relevantly, the amount of motion produced in given conditions can be both calculated and measured to within a reasonable margin, and a launch criteria set that provides a factor of safety against contact.

Regardless of the sea and wind conditions, the implication of the claim is that Sea Launch ignored a relatively straightforward criteria.

I give that claim zero credibility at the moment.

Oh this Roscosmos press release is classic!

A quick analysis of telemetry data received leads to a preliminary conclusion that the first-stage propulsion system and control system of the launch vehicle were operating normally.

Document review conducted during this day at the factory power plant (NGO "Energomash") and management systems (SPC AP) showed that there were no abnormalities in their production.

So what caused the rocket to pitch over? Tornadoes? Or the rocket made up its own mind to commit suicide? 

Obviously an issue not apparent in a quick analysis of the telemetry. Just because you have full thrust and none of the engineering data are out of bounds does mean everything is working properly. There's going to be a lot of data to search through, including for example, making sure the controller was issuing the commands it should have been.

The second claim is worthless. There is no way they've done any sort of meaningful review of all of the production and testing records in such short time.

[catdlr]

Don't know if anyone finds this interesting, but I put the earlier Intelsat launch side-by-side to this launch with youtube doubler: http://youtubedoubler.com/6KZU

bjornl,
Excellent.  I wanted to do this last night but didn't have the time.  Appreciate your effort.

[Rocket Science]

Don't know if anyone finds this interesting, but I put the earlier Intelsat launch side-by-side to this launch with youtube doubler: http://youtubedoubler.com/6KZU

Thank you and welcome to the forum!

[edkyle99]

Sorry for barging in late to the discussion,  but I've been offline all day. To my eyes this looked like an engine cutoff (emergency command cutoff) caused by a bad flight path. Am I close?

Ed Kyle

[Ben the Space Brit]

Sorry for barging in late to the discussion,  but I've been offline all day. To my eyes this looked like an engine cutoff (emergency command cutoff) caused by a bad flight path. Am I close?

I don't think anyone doubts that part of it.

What's in dispute is the cause of the bad flight path.  The vehicle and engine manufacturers were quick out the of the gate to blame the sea conditions or anything and everything other than their products.  They've calmed down since then and everyone is focussing on precisely what bit of the Zenit failed and why.

[mlindner]

Yes, but at 1:00 we see a flash in the video that can be the result from the impact on the waters. The platform is on the left and the flash illuminates the upper portion of the image.

Ah, missed that. I think that's a plausible explanation.

That's _an_ explanation. This could literally be anything. Cameras are not free from defects and this is coming over a webstream. This could easily be a flash from compression artifacts. I see them all the time in low quality streams and sometimes even in mpeg2 transport streams used for standard televsion. In other words we have absolutely no bearing on what this flash is, so best to not use it as information.

[ugordan]

This could easily be a flash from compression artifacts. I see them all the time in low quality streams and sometimes even in mpeg2 transport streams used for standard televsion.

I'm also familiar with compression artifacts and I disagree on this. However, I'm certainly not forcing anyone to use this conclusion as "information".

[spectre9]

I thought the reason why a rocket can't be steered is the engine gimbal doesn't work properly.

How is a rocket steered without the engine?

Obviously the engine is not at fault 

[sdsds]

What's in dispute is the cause of the bad flight path.

This will likely seem pedantic, but even the poor-quality webcast video gives strong hints about the cause of the bad flight path. The vehicle clearly pitches over inappropriately. (This is particularly evident in the side-by-side comparison -- thanks for that!) Please forgive the obviousness, but this indicates the force which moved the vehicle off its intended flight path was the thrust of the engine rather than, say, a lateral gust of wind moving the vehicle sideways while it was still pointed upwards.

At http://www.astronautix.com/engines/rd171.htm Mark Wade writes, "The RD-171 can be gimballed using bellows to 6 degrees normally but it has reached 8-10 degrees in tests." I don't fully understand what is meant at http://www.npoenergomash.ru/eng/engines/rd171m/ by, "The engine thrust vector control is carried out with creating the chambers unique bellows gimball joint" but I suspect they are saying each nozzle is independently gimballed below the combustion chamber. Is that correct? Hypothetically if one nozzle were to fail "hard over" couldn't the others compensate?

[pippin]

Look at Ariane 501. That looked pretty similar (although more dramatic, but then it was during daylight) and there the cause was the control system software, not the engine.

We here can't tell anything about the causes, there can be many different possible reasons.

[LouScheffer]

Hypothetically if one nozzle were to fail "hard over" couldn't the others compensate?

Two comments:
First, it would depend on how they do 2-plane gimballing.  If all 4 can gimbal in 2 planes, the 3 could out-muscle 1, and the rocket stays controllable.  But if one diagonal pair gimbals in one plane, and the other two at right angles, then the engine as a whole still has 2-plane gimballing, and roll control, but now a hard-over will force the opposite engine to hard-over as well, resulting in tiny (or negative) margins.

However, this seems unlikely from the images.  If each chamber can gimbal at least 6 degrees, there would be at least a 12 degree divergence of the exhaust plumes in this case.  But I (at least) can't see this in the video.

[russianhalo117]

Look at Ariane 501. That looked pretty similar (although more dramatic, but then it was during daylight) and there the cause was the control system software, not the engine.

We here can't tell anything about the causes, there can be many different possible reasons.

Do you mean Atlas V 501??

[pippin]

No, I mean Ariane 501 which was the first flight of Ariane 5

It failed shortly after launch because a malfunctioning flight control software sent it on a wrong path. In this case it set the control to "maximum deflection" with dramatic results but overall, it was kind of a similar looking failure.

[Garrettishere]

No, I mean Ariane 501 which was the first flight of Ariane 5

It failed shortly after launch because a malfunctioning flight control software sent it on a wrong path. In this case it set the control to "maximum deflection" with dramatic results but overall, it was kind of a similar looking failure.

I think there's a pretty big difference here. The Ariane 501 was a rather dramatic failure in that everything was looking good at first then out of nowhere it gimbaled to maximum deflection. But last night's launch appeared to be drifting off course from the very beginning.

[pippin]

Yes, I did already write that is was more dramatic.
However, the point still stands that it's obviously possible for a software error alone to cause such a dramatic incident, the engine doesn't need to be involved.
Since this was less dramatic there are probably a dozen more possible explanations for what happened.

I was answering to sdsds' claim that is must have been the engine.

[Art LeBrun]

Yes, I did already write that is was more dramatic.
However, the point still stands that it's obviously possible for a software error alone to cause such a dramatic incident, the engine doesn't need to be involved.
Since this was less dramatic there are probably a dozen more possible explanations for what happened.

I was answering to sdsds' claim that is must have been the engine.

Two similar failures to Ariane 501 were Titan 3C August 1966 (shroud failure) and Titan 4A August 1998 (power interruption).

[sdsds]

I was answering to sdsds' claim that is must have been the engine.

Oops, sorry! I absolutely never meant to make that claim.

[Galactic Penguin SST]

Yes, I did already write that is was more dramatic.
However, the point still stands that it's obviously possible for a software error alone to cause such a dramatic incident, the engine doesn't need to be involved.
Since this was less dramatic there are probably a dozen more possible explanations for what happened.

I was answering to sdsds' claim that is must have been the engine.

It could also be a malfunction in the guidance platform electrical hardware or even the IMU / gyroscopes - remember the infamous Chinese "Valentine's Day Disaster" (incidentally the last launch failure involving Intelsat)?



That one went down when the IMU had a short circuit that send the guidance crazy. If something in the guidance unit were manufactured out of spec, it might have led to such a failure. And there's also the engine gimballing mechanism.......