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Major Proton launch failure


Kryten

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But at 0:07 the opposite engine can be seen doing the same thing, as Bunsen said. However, that one engine does appear to have a shorter plume that others, as so;

index.php?action=dlattach;topic=32282.0;attach=531881;image

Maybe we're looking at engine failure after all. That could still be a guidance issue though, those engines can be throttled for increased control authority.

According to one Russian source, one of the engines did indeed fail at T+4 seconds - this being precipitated by one of the combustion chambers reaching three times the designated limit and the rocket itself lifting off about half a second earlier than scheduled.

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As soon as the tail end of the plume clears the buildings, around 0:03, you can see the exhaust is already deflected significantly to the right. By 0:04, the rocket is visibly leaning to the right. It then swings left, but further, and back to the right for the last time, probably overwhelmed by aerodynamics at that point. An amplifying oscillation like that makes me think somebody dropped a negative sign or plugged a gyro in backwards.

edit:

According to one Russian source, one of the engines did indeed fail at T+4 seconds - this being precipitated by one of the combustion chambers reaching three times the designated limit and the rocket itself lifting off about half a second earlier than scheduled.

Ooh, got a link for that? We've been pretty starved for actual info here.

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But at 0:07 the opposite engine can be seen doing the same thing, as Bunsen said. However, that one engine does appear to have a shorter plume that others, as so;

index.php?action=dlattach;topic=32282.0;attach=531881;image

Maybe we're looking at engine failure after all. That could still be a guidance issue though, those engines can be throttled for increased control authority.

Well, a engine failure is the most likely cause for this failure then something like the autopilot software. Maybe the turbopump failed, caused the weak thrust in one of the engines, and that caused this crash.

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Well, a engine failure is the most likely cause for this failure then something like the autopilot software. Maybe the turbopump failed, caused the weak thrust in one of the engines, and that caused this crash.

Quite incorrect. I don't know for certain on this, but I've heard this rocket had a unique configuration of stages compared to the normal proton. Now the first Ariane 5 was in theory just a big upgrade of the Ariane 4. The autopilot software should have worked fine, right? wrong. It crashed due to errors in the autopilot software.

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Now the first Ariane 5 was in theory just a big upgrade of the Ariane 4. The autopilot software should have worked fine, right? wrong. It crashed due to errors in the autopilot software.

As a sidenote, do you know what that error was? I was speaking with a colleague in the office about this only yesterday, as we were waiting for the Ariane V to be flight ready to launch Rosetta. This failure delayed the Ariane program, and had a knock-on effect on Rosetta... anyway, I digress...

The (original) autopilot software for the Ariane V had parts reused from the Ariane 4. At lift off, these parts, which were not felt to be important, turned out to be important, as they started receiving strange numbers from the larger launcher...

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Quite incorrect. I don't know for certain on this, but I've heard this rocket had a unique configuration of stages compared to the normal proton. Now the first Ariane 5 was in theory just a big upgrade of the Ariane 4. The autopilot software should have worked fine, right? wrong. It crashed due to errors in the autopilot software.

Well, the unique configuration was the Block DM-03 version for this launch. The rest was just like any normal Proton-M rocket. A autopilot error is not a very likely scenario, simple because the Proton-M was crashing too fast (sounds strange, I known) for it. The most likely cause is that one of the six engines of the first stage failed, and a serious cause for that is a failed turbopump.

Some text found:

"The analysis of the telemetry data has shown that the rocket's liftoff occurred nearly half a second ahead of time. Hence, the engines had not reached the necessary thrust capacity by this time," the source said.

In this situation, "the automated emergency system performed nominally: upon receiving information indicating that the engines did not reach the full thrust capacity, it started an emergency procedure to direct the rocket away from the launch pad," he said.

And this, something else found:

"It's either the control system or the engine that has caused the accident. If the accident occurred in the first 10 to 20 seconds, than the engine is likely to be the cause," a source in the space agency told RIA.

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I think that one of the radial boosters flamed out. a few seconds after clearing the tower, one of the radials on the right side stopped emitting the nice nominal burn jet of flame, and instead shot out an orange mist, as if it was venting partially burned fuel or something, then the rocket rolled to try and compensate, but flipped over and crashed into the pad. at least that's what i was able to glean from the vids. (there are higher quality ones from Russian news btw, you can click on a link in the ops vid.)

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I think that one of the radial boosters flamed out.

They are not boosters, but six 1-st stage fuel tanks with six 1-st stage engines, all sitting on huge shared central oxidizer tank.

a few seconds after clearing the tower, one of the radials on the right side stopped emitting the nice nominal burn jet of flame, and instead shot out an orange mist, as if it was venting partially burned fuel or something,

I'ts perfectly usual dumping of excess oxidizer (nitrogen tetroxide). You can see this on nearly every launch.

then the rocket rolled to try and compensate, but flipped over and crashed into the pad.

Over 2 km away from the pad.

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They are not boosters, but six 1-st stage fuel tanks with six 1-st stage engines, all sitting on huge shared central oxidizer tank.

I'ts perfectly usual dumping of excess oxidizer (nitrogen tetroxide). You can see this on nearly every launch.

Over 2 km away from the pad.

2 km isn't very far for rockets, its about a fifteen minute walk, and i assumed that the dump was a problem because it was right as the rocket rolled and crashed. i will stand corrected on the staging though.

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Some text found:

"The analysis of the telemetry data has shown that the rocket's liftoff occurred nearly half a second ahead of time. Hence, the engines had not reached the necessary thrust capacity by this time," the source said.

In this situation, "the automated emergency system performed nominally: upon receiving information indicating that the engines did not reach the full thrust capacity, it started an emergency procedure to direct the rocket away from the launch pad," he said.

Looks like that came from an Interfax wire piece (one example of the whole article). But, um, does that smell like a complete load to anybody else? The rocket had enough control authority to change direction twice, and enough thrust that it was not climbing perceptably slower than a normal launch (as best I can measure by watching youtube videos anyway -- any difference in the travel at 5 seconds is less than 1 second's worth). I know Roscosmos's approach to range safety is, how to put this politely, casual by the standards I'm used to, but "Oops, there was a transient thrust error at liftoff, but it's gone now, better zigzag a couple times and crash anyway" seems like an odd way to program a contingency procedure.

If the rocket has enough thrust to fly, and enough control authority to decide to fly away from the pad, wouldn't the safe thing be to burn off as much of that magnificently toxic propellant as possible before saying hello to the ground? Or at least stick as close as possible to the correct flight path for that magic 45 seconds, then give up? I really don't buy that the thing was following any sort of programmed course of action.

The article continues:

The Russian Investigative Committee has opened a criminal case over the crash of the Proton-M rocket, the Baikonur prosecutor's office said in a statement posted on its website.

"The investigative department of the Russian Investigative Committee at the Baikonur complex has opened a criminal case on this incident over evidence of a crime, put forward in the Russian Criminal Code Article 216 Part 1. The Baikonur prosecutor's office is overseeing the investigation," the statement said.

The Baikonur prosecutor's office is checking whether the law regulating preparations for launches and launches of rocket and space equipment was followed, at the order of the Russian Prosecutor General's Office, the statement said.

It looks like the blame-vectoring and ass-covering have reached full throttle already. I fear that further technical information is going to get filtered and mangled according to the politicians' choice of whose fault it was.
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Looks like that came from an Interfax wire piece (one example of the whole article). But, um, does that smell like a complete load to anybody else? The rocket had enough control authority to change direction twice, and enough thrust that it was not climbing perceptably slower than a normal launch (as best I can measure by watching youtube videos anyway -- any difference in the travel at 5 seconds is less than 1 second's worth). I know Roscosmos's approach to range safety is, how to put this politely, casual by the standards I'm used to, but "Oops, there was a transient thrust error at liftoff, but it's gone now, better zigzag a couple times and crash anyway" seems like an odd way to program a contingency procedure.

If the rocket has enough thrust to fly, and enough control authority to decide to fly away from the pad, wouldn't the safe thing be to burn off as much of that magnificently toxic propellant as possible before saying hello to the ground? Or at least stick as close as possible to the correct flight path for that magic 45 seconds, then give up? I really don't buy that the thing was following any sort of programmed course of action.

The article continues:It looks like the blame-vectoring and ass-covering have reached full throttle already. I fear that further technical information is going to get filtered and mangled according to the politicians' choice of whose fault it was.

If the engines didnt have enough thrust capacity and emergency procedures were activated, there would probably be problems in control resulting in gross overcompensation before desired effect was achieved.

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Coming in from Orbiter-Forum (my other internet home):

Seems that one engine was suffering a turbopump failure/fire. Initial rocket-based telemetery findings indicated that temperatures in one of the engine compartments exceeded 1200*C.

Info is from here, and translated by GalacticPenguinSST at O-F.

EDIT: Current hypothesis and telemetry findings are here.

Double Edit: AHA! Here's the really meaty bit from that link:

On July 4, a source at GKNPTs Khrunichev reported on the online forum of the Novosti Kosmonavtiki magazine that an interface plate connecting a series of cables from ground equipment to the aft end of the launch vehicle, had separated earlier than planned. The plate, designed to shift by around 5 millimeters, normally separates after the rocket starts moving off the pad. However in this case, it apparently moved by as much as 11 millimeters before the rocket had a chance to leave the pad. As a result, all electrical connections between the pad and the rocket were severed, while the vehicle's engines were yet to develop their full thrust. At that point, the engines could still propel the rocket into the air, but could not keep it in stable flight. (According to the telemetry, the pressure inside the combustion chambers of the engines was 90 kilograms per square centimeter, instead of required 150 kilograms per square centimeter.) The flight control system could interpret such a situation as an emergency, (even if the rocket was still standing on the launch pad), and sharply throttle all engines to a maximum thrust in order to prevent the vehicle from falling onto the launch pad. In turn, the sharp increase in thrust could cause a fire detected by temperature sensors.

If confirmed, such a scenario would make the cable interface plate of the launch pad a culprit in the abnormal liftoff and the subsequent crash. The exact reason for the plate to go down was not immediately clear, but it could be due to its wrong installation or a mechanical failure. The erratic behavior of the rocket during its short flight also remained to be explained under this scenario.

Looking forward to learning more from the investigation.

Edited by MaverickSawyer
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http://www.interfax.com/newsinf.asp?pg=2&id=429110

MOSCOW. July 9 (Interfax-AVN) - The crash of a Proton-M rocket shortly after take off on July 2 was due to a human error, a source close to experts probing the accident told Interfax-AVN.

"The angular velocity sensors were wired up with the wrong polarity. Therefore, the rocket was orientated incorrectly," he said.

...

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If I'm reading that right, it just says that the engine was ignited 1.7 seconds before liftoff. Not that anything failed.

Note the 'lift-off switch'-0.4 seconds before nominal, exactly what happened on this flight. And of course nothing failed-that's my point.

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