Proton-M Failure Reaction and Discussion Thread - July 2, 2013

[ugordan]

If that failure happened on a Soyuz it should be fully survivable - LES would be activated as soon as the anomalous pitch event occurred. Loss of mission, but the crew should survive.

With broken ribs, arms and possibly legs. The one time a Soyuz LAS fired it beat the heck out of the crew.

You prefer the alternative?

I would think they give more attention to quality assurance on manned launches than to their unmanned launches and the launch track record seems to support that.

Would ground the program no different than a LOCV event.

Name one such an abort event/system that wouldn't. LAS should have no bearing on initiating an anomaly investigation.

[edkyle99]

Maybe I was overreacting.

As an Australian I thought it was my right to be pushy about environmentalism.

Cleanup will, or should, be an issue.  The following page discusses hydrazine cleanup at Rocky Mountain Arsenal.
http://www.rma.army.mil/cleanup/facts/hydrazin.html

It says that "Hydrazine and UDMH are unstable in the natural environment and rapidly decompose when exposed to the atmosphere".

So far so good.  The stuff dissipates and what is left mixes with water.  It can be washed into a catch basin.

But then it says that "[a] decomposition product of UDMH is NDMA, a suspected human carcinogen".  The trace NDMA remnants forced RMA cleanup to resort to treating the waste water used to rinse the site previously.  They used a special incinerator to do the job.

 - Ed Kyle

[owais.usmani]

AZ has some updates:

http://www.russianspaceweb.com/proton_glonass49.html

In the meantime, engineers in Baikonur started deciphering available telemetry from the failed rocket. One source reported an emergency cutoff in one of six engines on Proton's first stage in the first few seconds of the failed launch. Other unofficial sources then elaborated that a failed steering mechanism placed the engine into an extreme position making it too difficult for the flight control system to correct wrong direction of thrust with remaining five engines.

[Danderman]

Hmm, the "wobbling" of the rocket from left to right is very strange - I can't see how this can happen either with (one or more) engine shutdown (it doesn't seems to be going slower than normal) or with engine gimballing problems (it would just veer off course in one direction - just like the Sea Launch Zenit did earlier this year).

I wonder if the guidance system got zapped or went out of control (either with the electric circuits or with the software) - this failure looks a lot like many of the spectacular launch failures worldwide (CZ-3B / Intelsat 708, Ariane 5 / CLUSTER, Titan IV A-20 etc.)....

IMHO, it seems obvious that the motion control system completely failed. This is not the same issue as occurred with SeaLaunch, when the thrust vector control system failed. In this case, either the Bizer failed, or the  cabling from the Bizer to the engine compartment somehow failed.

[Danderman]

Has anybody noticed this? There are reports that the cause could be the Blok DM-03 upper stage. And if google translate is not failing me, it is from RSC Energia itself. 

http://ria.ru/science/20130702/947021354.html

http://ria.ru/science/20130702/946977917.html

http://www.energia.ru/ru/news/news-2013/news_07-02.html

If this is true, then I guess Vitaly Lapota should pack his bags.

The RSC Energia statement has no mention of the role of the Block-DM-03, except that it was being carried by the Proton-M.

[Prober]

Don’t be so quick to call for the retirement of the Proton. It has had 2 launch vehicle failures in 119 flights, which is not too terribly different than 2 launch vehicle failures in 135 flights for Shuttle.  And don’t say anything like “but they are 2 entirely different kinds of vehicles” because when the launch sequencer reaches zero on any vehicle, it is the entire launch system that is igniting. Proton is not “just” a rocket, it is a launch system that has a very respectable mission history, including Zarya, the 1st module of the ISS. You may not like what it uses for propellants but there is no denying that it works, and works well.

I disagree with you... past success doesn't mean you continue doing the same thing.  We had many successful Titan launches yet we moved on.  Had many successful Shuttle launches... We moved on.
 
The Russian plan is behind on the replacement launcher.  Best to double the efforts and get the replacements operational.  Also remember the Russians are leasing the location and its not right to continue against the owners wishes.

[owais.usmani]

Has anybody noticed this? There are reports that the cause could be the Blok DM-03 upper stage. And if google translate is not failing me, it is from RSC Energia itself. 

http://ria.ru/science/20130702/947021354.html

http://ria.ru/science/20130702/946977917.html

http://www.energia.ru/ru/news/news-2013/news_07-02.html

If this is true, then I guess Vitaly Lapota should pack his bags.

The RSC Energia statement has no mention of the role of the Block-DM-03, except that it was being carried by the Proton-M.

Sorry about that post, I got tricked by google translate 

[Danderman]

A Bizer failure would have significant impacts on the Russian space program, since so many other vehicles use Bizer.

It would have to be determined if there were a quality control problem, or whether an undiscovered code problem was the culprit.

[OV135]

Hopefully photos of the debris will be shown to give an idea of the cause of the failure. 

[Kabloona]

Some interesting background material. Apparently this will be good for the local scrap metal salvagers, but bad for the cattle.

http://www.thelivingmoon.com/41pegasus/02files/Space_Debris_04.html

[Ben the Space Brit]

I'm shaking my head right now, having just come from the comments page of the Independent, the paper I read the most.  Over half the comments so far have claimed that this is US sabotage in revenge for the Edward Snowden affair.  This is the sort of hyper-political shallow mindset that makes me despair sometimes.

Sorry, just needed to vent.

A little speculation: Could the observed attitude instability have been caused by turbo-pump issues such as a defective bearing that was causing occasional under-revs?

[ugordan]

AZ has some updates:

http://www.russianspaceweb.com/proton_glonass49.html

In the meantime, engineers in Baikonur started deciphering available telemetry from the failed rocket. One source reported an emergency cutoff in one of six engines on Proton's first stage in the first few seconds of the failed launch.

This image seems to rule out this cause, 6 chambers glowing well into vehicle disintegration phase.

Other unofficial sources then elaborated that a failed steering mechanism placed the engine into an extreme position making it too difficult for the flight control system to correct wrong direction of thrust with remaining five engines.

I speculated on this here, still it makes me wonder why the vehicle would overcompensate and produce wild pitch swings. Perhaps at that point the FTS system already took over and decided to do a pad-flyaway maneuver?

[Ben the Space Brit]

Other unofficial sources then elaborated that a failed steering mechanism placed the engine into an extreme position making it too difficult for the flight control system to correct wrong direction of thrust with remaining five engines.

I speculated on this here, still it makes me wonder why the vehicle would overcompensate and produce wild pitch swings. Perhaps at that point the FTS system already took over and decided to do a pad-flyaway maneuver?

A lot depends on the energy margin available.  If the IU calculated that compensating from the TVC anomaly so early into the flight plus the cosine losses was too great to keep on a viable trajectory, it may have auto-executed an abort.  The attitude might have corrected eventually but it was a very violent initial motion and a lot of energy that otherwise would have been used for the ascent would have been used up correcting and dampening down the motion.

[Kabloona]

I speculated on this here, still it makes me wonder why the vehicle would overcompensate and produce wild pitch swings. Perhaps at that point the FTS system already took over and decided to do a pad-flyaway maneuver?

I don't know how the Proton attitude control system works, but it appears that, after the first attitude departure/correction sequence, the roll rate becomes significant and overwhelms the guidance system. I don't see how recovery would be possible with that roll rate.

[ugordan]

Seems to me that roll alone should be easy to control given all the other engine pairs (heck, probably doesn't even need to be an *opposing* pair if you don't mind some pitch/yaw as well), but I guess I can see how single plane gimballing could go the other way - induce roll problems while controlling yaw/pitch when one engine goes wild.

Could what we're seeing here be the price you pay for such a single plane gimbal freedom system?

[Galactic Penguin SST]

<amateur detective mode>
From the available videos, it seems that the rocket had 3 pitch overs - each one larger than the previous one, and it seems that the rocket was in an excessive roll right after liftoff that continues to accelerate till breaking up.

I have a hypothesis that was first mentioned by a Russian forum member here:

1. For some reason the Proton started to roll excessively within a few seconds of liftoff - reasons not yet known as this point.

2. The excessive roll caused the rocket to start to pitch over towards a certain direction due to torque from the angular acceleration (remember tau = I * alpha?) - it may have been magnified by the initial pitch over command.

3. Sensing that the rocket is pitching over limits, it attempts to gimbal some of the engines towards the other direction, but since the roll is accelerating (and may already be out of control by then), it over-corrects in the opposite direction and caused the rocket to lose pitch (and almost certainly yaw) control.

4. By then the worsening roll puts the rocket in a positive feed-back mechanism - the more the rocket tries to correct the pitch, the more it over-pitches in the other direction. This third pitch over finally sends the rocket horizontally and points it towards the ground. The rocket continues to roll crazily until it breaks up - heads first (tau = r * F) and then the whole rocket as the fuel tanks blasted open. Then it impacted on the ground.

So what caused the excessive roll? Engine loss or partial thrust? Problem with engine gimbals? (failure in one of the six engines is apparently enough to send the rocket towards the ground) Erroneous data from the inertial platform sending the rocket to roll violently? Control system software bug in a specific environment that went out of control? All these would probably be known when all the telemetry data is analyzed in a few day's time.

Any comments on my thoughts?

</amateur detective mode>

[Danderman]

AZ has some updates:

http://www.russianspaceweb.com/proton_glonass49.html

In the meantime, engineers in Baikonur started deciphering available telemetry from the failed rocket. One source reported an emergency cutoff in one of six engines on Proton's first stage in the first few seconds of the failed launch.

This image seems to rule out this cause, 6 chambers glowing well into vehicle disintegration phase.




I speculated on this here, still it makes me wonder why the vehicle would overcompensate and produce wild pitch swings. Perhaps at that point the FTS system already took over and decided to do a pad-flyaway maneuver?

The Flight Termination System operates by detecting an unrecoverable anomaly, and then causing an immediate shut down of all engines. There is no "flyaway" mode.

The fact that the engines were operating while the vehicle was in an unrecoverable mode (upside down) tells me that the motion control system completely failed.  This is what is known in the business as a "clue".

[zeke01]

Some interesting background material. Apparently this will be good for the local scrap metal salvagers, but bad for the cattle.

http://www.thelivingmoon.com/41pegasus/02files/Space_Debris_04.html

Thanks for this.  I've often wondered about how people living underneath the flight path dealt with the hazards of the discarded stages.  Incredible and intolerable.

[Stan Black]

AZ has some updates:

http://www.russianspaceweb.com/proton_glonass49.html

In the meantime, engineers in Baikonur started deciphering available telemetry from the failed rocket. One source reported an emergency cutoff in one of six engines on Proton's first stage in the first few seconds of the failed launch.

This image seems to rule out this cause, 6 chambers glowing well into vehicle disintegration phase.




I speculated on this here, still it makes me wonder why the vehicle would overcompensate and produce wild pitch swings. Perhaps at that point the FTS system already took over and decided to do a pad-flyaway maneuver?

The Flight Termination System operates by detecting an unrecoverable anomaly, and then causing an immediate shut down of all engines. There is no "flyaway" mode.

The fact that the engines were operating while the vehicle was in an unrecoverable mode (upside down) tells me that the motion control system completely failed.  This is what is known in the business as a "clue".

In the first few seconds the engines are not terminated to save the launch site.

[Danderman]

<amateur detective mode>
From the available videos, it seems that the rocket had 3 pitch overs - each one larger than the previous one, and it seems that the rocket was in an excessive roll right after liftoff that continues to accelerate till breaking up.

I have a hypothesis that was first mentioned by a Russian forum member here:

1. For some reason the Proton started to roll excessively within a few seconds of liftoff - reasons not yet known as this point.

2. The excessive roll caused the rocket to start to pitch over towards a certain direction due to torque from the angular acceleration (remember tau = I * alpha?) - it may have been magnified by the initial pitch over command.

3. Sensing that the rocket is pitching over limits, it attempts to gimbal some of the engines towards the other direction, but since the roll is accelerating (and may already be out of control by then), it over-corrects in the opposite direction and caused the rocket to lose pitch (and almost certainly yaw) control.

4. By then the worsening roll puts the rocket in a positive feed-back mechanism - the more the rocket tries to correct the pitch, the more it over-pitches in the other direction. This third pitch over finally sends the rocket horizontally and points it towards the ground. The rocket continues to roll crazily until it breaks up - heads first (tau = r * F) and then the whole rocket as the fuel tanks blasted open. Then it impacted on the ground.

So what caused the excessive roll? Engine loss or partial thrust? Problem with engine gimbals? (failure in one of the six engines is apparently enough to send the rocket towards the ground) Erroneous data from the inertial platform sending the rocket to roll violently? Control system software bug in a specific environment that went out of control? All these would probably be known when all the telemetry data is analyzed in a few day's time.

Any comments on my thoughts?

</amateur detective mode>

There is a both a bug and a feature in your thesis.

The feature is that you suggest that an initial failure of the motion control system produced a pitch maneuver and that the attempt to reduce the pitch invoked cross coupling.

The bug is that you are focused on the symptoms of the initial failure, and not the initial failure itself. IF the motion control system produced an unrecoverable failure, worrying about how the vehicle responded to the unrecoverable failure is not too productive (because of that "unrecoverable" part).

The real question is why that initial pitch maneuver was generated.