Article: NTSB: Emirates 777 continued flight after loud bang, messages

[sAx_R54]

I disagree....

I hear your point, but how do you rationalise this? No MEL list would have included such damage, so the plane would have been deemed unsafe to depart in the post landing condition, right? But the same damage inflicted whilst air borne is deemed safe enough for a 5-hour journey, right again?? Therein lies my difficulty to comprehend how you and your fellow professionals are able to see equivalence in this contra-indication.

[Wizofoz]

Of course you wouldn't depart with it.

But, once it has happened, you are stuck with it.

You haven't answered my question- If it isn't going to get any worse, why is it safer to land immediatley than to carry it to a convienient base?

You also can't dispatch with only one RAD ALT- would you land ASAP on some marginal wilderness strip if THAT happened in flight?

Once dispatched, the MEL does not apply, and it is up to us to make the best decision we can with the info available.

[Lord Spandex Masher]

sAx, the MEL only refers to pre-departure. I think that was covered earlier in this thread.

The ECL/QRH is what matters after departure, ie. pushback.

For example, on the Embraer that I used to fly the APU shut itself down during push back, inbetween engine starts, due to an overspeed.

The MEL states that the APU must be secured prior to departure, CBs pulled etc..

The ECL states that the APU must be turned off, that's it.

See the subtle difference?

Not that that example is relevant to this discussion but the use of MEL and the ECL/QRH is.

[sAx_R54]

...You haven't answered my question- ...

I am unable to answer your question, but I wonder if you are able to answer my conditional preposition? If all the factors remained the same and outcome followed had caused harm, would you have supported the decision to continue the flight?

[redsnail]

Having being involved with an incident at a Moscow airport (UUWW), I'd rather continue to Dubai. (Mayday situation is different of course)

Regardless of the MEL, the aircraft would have been grounded for a minimum of 3 days while the Russian authorities "dealt" with the situation.

[Wizofoz]

I DON'T support or reject the decision itself, but am willing to try and provide reasons why it was made.

Simply put, if you cannot provide a reason why continuing was less safe, how is the question even relevent? If they had RETURNED and crashed, would that have made THAT a bad decision?

I UNDERSTAND that the crew did it's best given the information at hand, and don't imagine I could have done a better job, no matter which way I went, under the circumstances.

And yes, I would have supported the crews doing its' best, even if the outcome had not been so good. There have been MANY incidents where the crew acted in good faith, only to have a bad outcome.

We learn from these, and no doubt will do so from this incident.

[sAx_R54]

I DON'T support or reject the decision itself...

I accept that as a reasonable response and I respect you for it. I have read countless of Accident Reports and scenarios which have lead to disaster, where cause and effect have been intrinsically linked (swiss cheese model using your vernacular). Now I am no aviation specialist and I do not possess a crystal ball, but time and time again, past incidents receiving the benefit of PPRuNe inquisition alongside the transcription from CVR's/FDR's have shown pilots trapped by outcomes determined by fate.

Whilst the T7 is ETOPs compliant and thus able to fly 3.5hrs on a single engine, if resulting damage had subsequently progressed a single engine shutdown (damaged fan blade, increasing engine vibration, etc) and there was deteriorating weather condition at all reasonable alternates, attempting to balance asymmetry with strong windshear (swiss cheese), may well have occasioned the matters where a collective wisdom could be applied when the CVR stops recording.

Lets face it, more serviceable aircraft have sadly been caught out without any advisory status warning of less than 100% systems performance.

[Wizofoz]

Whilst the T7 is ETOPs compliant and thus able to fly 3.5hrs on a single engine, if resulting damage had subsequently progressed a single engine shutdown (damaged fan blade, increasing engine vibration, etc) and there was deteriorating weather condition at all reasonable alternates, attempting to balance asymmetry with strong windshear (swiss cheese), may well have occasioned the matters where a collective wisdom could be applied when the CVR stops recording.

...And the presence of such factors would have been considered in the decision making process. The idea is to assess ALL relevent data ON THE DAY- not what might happen in some fantasy situation.

If the above is your main objection to the continue decision, and forcast weather was fine'n'dandy en-route (as it usually is) would that temper your critisism?

[sAx_R54]

...not what might happen in some fantasy situation...

You don't need to look too far in this Forum to see the Reality that fantasy might try to ignore. My criticism is not the the pilots per se, but of the industry as a whole. Emirates may have a policy called get the baby home unless both engines are on fire, for all I know, so no blame attributable to the pilots. The real fantasy is that the traveling public do not understand that determination of the risks, does not principally take them into consideration.

[HPSOV L]

Emirates may have a policy called get the baby home unless both engines are on fire, for all I know

While there are plenty of things I could complain about EK. commercial pressure to complete a flight in the face of any inflight contingency, is not an area I ever had any concerns about.
Sometimes these aviation discussions turn into a cockfight about who can take the most conservative (and therefore most professional so the argument goes) appearance.
Wizofoz; I take my hat off to your ability to organize logical argument out of the white noise of Pprune.
Most posters are firm disciples of philosopher Schopenhauer's satirical "38 Ways to Win an Argument"

[Enjoy the view]

Down through Azerbajan, Uzbekistan, Iran, Kuwait, Bahrain, UAE.

Non-Etops, so never more than 420NM from an Adequate, though in this case, never more than 45 minutes from a company designated Alternate.

I think that Uzbekistan is not exactly on this route (quite offset to the East), but it doesn't matter too much...

However EK doesn't seem to serve many destinations between Moscow and Tehran along the route (possibly Larnaca a bit more to the West?), so that would mean quite a large territory to cover before reaching a suitable commercial station capable to meet the tech aircraft and assist with passengers and so on... It wouldn't look "too good" to justify why half way down route, due to an engine failure, the aircraft had to land somewhere remote....?

What's the company policy in that regard?

[sAx_R54]

..Most posters are firm disciples of philosopher Schopenhauer's satirical "38 Ways ...

Cyber blog tennis can be a pointless exercise for sure. The parallel threads (nee worlds) of AF447 (pg 40-->) and the US Airways Captain are succinct descriptions of the view I would champion. On this thread however lets take the view that the certainty of safe outcome was never less than 100%.

If I am Schopenhauer's disciple, then it is pure serendipity as I know not of such philosophy.

[HPSOV L]

Not aimed at you sax - your points are constructive and well argued.
PS: Worth googling that Schopenhauer reference - you'll get a good laugh out of it.

[Wizofoz]

What's the company policy in that regard?

An engine shutdown is Land At Nearest Suitable Airport and commercial considerations are specifically NOT to be part of that assesment.

If that had happened (and similar things have in the past) it would be a case of "Well, we tried!!".

HPSOV TA!

Look up Brian Dunnings "in Fact" series on "Logical Fallicies"- You'll find they are a staple of many PPRUNE posters!

[Fubaar]

your points are constructive and well argued.

I couldn't disagree more. The guy has a point of view set in stone and won't hear any argument to the contrary, even from very experienced captains on the type. As someone (more than one) has said before me, status messages are just that - status messages that a lot of very clever engineers and test pilots decided should inform the crew of a degradation in aircraft systems that were not important enough to require crew action.

[Desert Dawg]

Geesh..!! The amount of crap spewed out in this thread regarding a minor incident just boggles the mind...! Hashing this issue to death is becoming a laughable matter...

Guys - get over it...! It's done.. over.. Finished.

Pax, crew and plane are all safe. MCC and engineering have fixed the issues. Life moves on.

[Dani]

There are two arguments hidden in this discussion:

One is the decision the crew made. There are always different points of views in such cases. We can safely argue that most pilots wouldn't return inflight based solely on status messages. All options have to be weighted, inclusive the weather and traffic situation in Moscow.

The other point is the system itself. For me it's amazing that you can loose such a big portion of an engine without loosing thrust, or even having no warnings. They lost basically most of their duct wall and outer cowling, still there is no sign of it in the cockpit? Eighter 777 are wonderfull aircraft... - or the opposite. Wouldn't there be a massive deterioriation of aerodynamics inside the fan duct? I can hardly believe that all this honeycomb material went through the fan or through the outside without causing damage on the engine itself.

And if you loose a whole chunk of your reverser, doesn't that trigger any warning on the flight deck? I'm really astonished.

How big is the increase in fuel flow? No temperature deviation?

And on a 5 hours flight over sparsely populated area, wouldn't there be time to stand up from your "armchair" and have a look on your troubled engine? I guess the feedback to maintenance would be very much different than based on status messages, and so would be the answer from MCC.

So, all in all, I tend to be in the group of "there was something wrong" in this incident. But more information would be necessary to get a definite picture.

[sAx_R54]

...The guy has a point of view set in stone and won't hear any argument to the contrary, even from very experienced captains on the type...

My point of view is set in 'passenger' not in stone! I believe that this thread was started by a T7 pilot and he/she amongst others similarly on this thread would have conducted an immediate return. Other T7 pilots (you?) would have elected to continue. This strikes me as a sort of aviation arrogance, where risk can freely be moved from contained to unknown, as the industry knows what type of risk passengers would like to experience on any given day. And if there is a greater economic need to reduce the cost profile of operation, then passengers have to join in regardless of their view. It may well be argued that is exactly what we purchase when we buy a ticket, but the disembarking passengers in Bahrain might disagree on seeing site of the damage to the aircraft.

If you are an experienced pilot of type, then for sure it might be great to convey your aviation macho-ism to fellow colleagues over a pint, as how you danced on the rudder pedals in a manner which Fred Astaire would have delighted, following failure of thrust asymmetry compensation, as you counteracted increasing yaw and balanced the plane on the precipice of controllability, after engine shut-down! Boys own story, fantastic stuff! But we passengers may not have enjoyed it as much.

I don't possess your insight, but for those times when luck and skill run out, we have threads that run over 200 pages of what pilots should done to prevent the situation.

[fft100]

Fuubar wrote

"As someone (more than one) has said before me, status messages are just that - status messages that a lot of very clever engineers and test pilots decided should inform the crew of a degradation in aircraft systems that were not important enough to require crew action. "

I admire your confidence in computer systems. However, unfortunately, they can only give messages (status, warning or other) for something they know about. Therefore, if there are no sensors, gauges or other inputs to monitor then they cannot tell you about it. I would guess that the cowling was not connected to any sensor, so the computer was not able to pass on the info that it was not all there.

Pilots can only make decisions based on the info they have, but it is not wise to assume that all the info is available. Computers are 'smarter' than they used to be, but i am not sure it is wise to rely completely on them. I used to write software for banks. They are not infallible. They are not God. People should use them with care.

[charlies angel]

sax

Dont make it so complicated and black and white.

I'm a taxi driver on the motorway with a passenger and I get an oil level low warning and I decide to to carry on to the next service station. On checking it is noted that I do in fact need a litre of oil. No drama.

A colleague of mine has the same warning the next day but decides to pull over onto the hard shoulder and call out the AA for a tow to the service station.He also needs a litre of oil. No drama.


Who out of our taxi driving chums is the most/least correct?
Same end result? Totally different decisions were made?

What is the perceived danger to the passenger? Is it the same for each scenario?

Now both scenarios could have had a different result.
What if the first taxi had blown its engine?
What if the advisory was false?
Maybe the AA van breaks down towing our friend!?

So many imponderables.

Command decisions are a healthy mixture of technical knowledge,experience,commercial awareness,team input and many more imponderables.

We use the grey matter because most scenarios are not completely black and white