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

[Liryc]

I don't know if they have a pyro safety system (such as the european launchers) or a simple engine shutdown procedure (zoyuz).

Automatic engine shutdown.

thanks

[ugordan]

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.

[smoliarm]

INTERFAX published this explanation of failure (the translation is mine, google seems to dislike the topic

Причиной неудачного запуска ракеты могло стать волнение океана
The cause of the unsuccessful launch of the missile could be the rough sea

01 февраля 2013 года 12:28
Москва. 1 февраля. INTERFAX.RU
- Авария ракеты-носителя "Зенит" могла произойти из-за сильного волнения Тихого океана в районе старта, сообщил "Интерфаксу-АВН" источник в ракетно-космической отрасли.
По его словам, со вчерашнего дня в районе старта зафиксировано повышенное волнение, стабилизирующие двигатели пусковой платформы едва справлялись с поддержанием устойчивости.

Moscow. February 1. INTERFAX.RU
- Accident of LV "Zenith" could be due to a heavy sea in the Pacific Ocean near the start, a source in the space industry said to "Interfax-AVN".
According to him, since yesterday at the launch site recorded rough sea, stabilizing engines of the launch platform can hardly maintain the platform’s stability.

...

Для проведения пуска ракеты необходима полная устойчивость платформы, поскольку все навигационное и гирооборудование платформы и ракеты-носителя привязано к месту старта.

Launch requires the full platform stability, since all navigation and giro- systems of the platform and the rocket are tied to the launch site. (sorry, but I have to give literal translation...)

...

Учитывая, что ракета-носитель изначально пошла не по нужной траектории, "можно говорить о том, что стразу после старта системы ракеты определили нештатную ситуацию, вызванную неустойчивостью платформы, и чтобы не повредить ее, включили двигатели на увод ракеты от пусковой платформы "Одиссей", сказал он.

Given that the rocket did not initially go to the right path, "we can say that right after the launch the guidance system of missile identified emergency situation (caused by the instability of the platform), and to avoid damage, initiated the diverting flight path leading missile away from launch platform"Odyssey ", the source said.

http://interfax.ru/society/news.asp?id=288200
A bit more detailed dialogue with (presumably) the same source is here:
http://www.gazeta.ru/social/news/2013/02/01/n_2734521.shtml

These both sites I know as reliable. I do not mean of course they are 100% error-free, but I never saw them reprinting from doubtful source.

However, in this case it is hard to believe their version:
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=30213.0;attach=493364;image

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” ??

I'd be very grateful for expert comments.

[Ben the Space Brit]

Do we have any idea of the reason for the engine shutdown ?

It was almost certainly a safety measure.  Looking at the footage, the vehicle was at a 30-45 degree angle just before shutdown, so it was necessary to abort the flight at the earliest moment rather than let the rocket turn into a runaway.

[Ben the Space Brit]

(snip)

I'd be very grateful for expert comments.

No expert here but I'm not sure about this theory.  Surely Sea Launch wouldn't have gone ahead with the launch if the swell was outside of safety constraints? Additionally, the footage showed no indication that the platform was rocking excessively - the cameras on the command ship would have picked that up.

No, as a non-expert, my guess at this stage is either a hardware failure in the TVS or a software failure in the IAU that jammed the RD-170 in a hard-over pitch or yaw.


[edit]
Okay, going into assumption mode here.  The Zenit was probably still very subsonic at the point of the abort.  Aerodynamic forces would seem to require a nose-first contact with the ocean so the payload is certainly destroyed.  Assuming this is correct, then the vehicle itself might have sunk more-or-less intact (save some ruptured prop tanks and disconnected stages).  So, given the location of the launch, what is the probability that the IAU and the core stage engine could be recovered,  airline accident investigation style, for analysis?

[spectre9]

A stark reminder of how difficult it is to point a rocket towards the right orbit even after you've gone to the difficulty of taking the rocket to the equator.

If the motion of the launch platform can be blamed for the failure I'd say that's a very poor excuse.

[anik]

I was told that there was not 100% thrust of engine at rocket liftoff.

[robertross]

I was told that there was not 100% thrust of engine at rocket liftoff.

Thanks Anik. That would seem to fit.

Sad news of the failure.
I wonder if they need to recover the satellite (or portions thereof) for security reasons?

[ugordan]

I was told that there was not 100% thrust of engine at rocket liftoff.

If that's the case, it's a really "nice" feature - to have the vehicle issue a launch commit command even though its propulsion system didn't satisfy nominal operation criteria. I find that a little hard to believe.

[Galactic Penguin SST]

I was told that there was not 100% thrust of engine at rocket liftoff.

Thanks Anik. That would seem to fit.

Sad news of the failure.
I wonder if they need to recover the satellite (or portions thereof) for security reasons?

I would have thought that any remains of the satellite (remember that the rocket exploded when hitting the ocean horizontally) would sink into the ocean? The ocean depth at the launch site is around 4800 meters, don't think salvage operations has ever been done at such a depth.

[GClark]

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.

They're not going to be able to blame this one on the local weather conditions (JMNSHO, of course).

[Galactic Penguin SST]

Some basic rocketry question: since the RD-171 is a four thrust chamber engine, does it mean that if one (or lets say two) of them have developed leakage due to nozzle/thrust chamber damage, the others can still function properly? Would it have affected engine gimballing as well?

[just-nick]

Did I read right that the Zenit-3 had a Blok-DM upper stage? What's the propellent on that?

All the stages on the Zenit-3SL use kerosene and LOX.

Block-DM third stage also has some hypergolics for ACS and the SOZ ullage motors. So there's some toxicity risk there, in addition to payload propellant.

[Prober]

Command shutdown for an FTS? Isn't that what Soyuz does? Because that sure looks like shutdown, cough, sputter, and fade away rather than passing behind a cloud. If trajectory was off, command is issued and then it is up for 25 seconds, down for about the same, and then end of mission.

Well, FTS stands for Flight Termination System. That does not necessarily means that you blow up the vehicle. Just shutting down the engine also will terminate the flight, albeit with slightly less spectacular results.

wonder what they can recover?

[Blackstar]

The ocean depth at the launch site is around 4800 meters, don't think salvage operations has ever been done at such a depth.

That's not a problem. The US Navy did a recovery operation at 14,400 feet in 1972. Remotely operated vehicles can now operate at that and great depths. Only issue is whether it is worth the expense.

[input~2]

According to the manufacturer of the engine, Energomash, the engine is not to be blamed..
http://www.interfax.ru/news.asp?id=288295

[Kim Keller]

Am I remembering correctly? After the NSS-8 launch failure, did Atlas stand down because of potential commonality between RD-170 and RD-180? The Atlas V launch of Landsat 8 (LDCM) is at T-11 days and counting....

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.

[douglas100]

I was told that there was not 100% thrust of engine at rocket liftoff.

If that's the case, it's a really "nice" feature - to have the vehicle issue a launch commit command even though its propulsion system didn't satisfy nominal operation criteria. I find that a little hard to believe.

Have to agree with that. If the system allows the vehicle to lift off under these circumstances, then there's something seriously wrong with the system.

[Galactic Penguin SST]

I was told that there was not 100% thrust of engine at rocket liftoff.

If that's the case, it's a really "nice" feature - to have the vehicle issue a launch commit command even though its propulsion system didn't satisfy nominal operation criteria. I find that a little hard to believe.

Have to agree with that. If the system allows the vehicle to lift off under these circumstances, then there's something seriously wrong with the system.

IIRC the RD-171 cannot shutdown once a preliminary thrust level is reached (I think there was some kind of a membrane that has to be broken near the fuel inlet at ignition, and there was a SL Zenit launch that was aborted just after ignition at the request of the spacecraft controller, and as the process is irreversible the whole team had to set sail back to Long Beach to replace the first stage engine - am I correct?)....

[woods170]

I was told that there was not 100% thrust of engine at rocket liftoff.

Thanks Anik. That would seem to fit.

Sad news of the failure.
I wonder if they need to recover the satellite (or portions thereof) for security reasons?

No. In nearly 5 kilometres of water it is quite expensive to retrieve anything. It's very much doable with todays technology, but also very expensive. Anyone interested in the technology of this satellite will be of much cheaper by gaining the same knowledge thru industrial espionage.