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-   -   Emirates B777 gear collapse @ DXB? (https://www.pprune.org/rumours-news/582445-emirates-b777-gear-collapse-dxb.html)

CONSO 3rd Aug 2016 18:34

FWIW re Engine over the wing
 
at the very start of the video at
Flights to resume after Emirates flight catches fire at Dubai airport | The National

NOTE- scroll down a ways to the description that starts

Boeing’s 777 model is the largest twin-engine airliner in production and the most used wide-body. Emirates is the largest operator of the plane. The aircraft is also one of the safest jets in the world, with only a handful of them having suffered irreparable damage since the model’s introduction, according to Aviation Safety Network.
and look at the video below.

one can clearly see the engine above the wing. I'm sure it puzzles many as to how it got there.:sad:

Consider the following.

!) BA design for decades ( and probably Airbus ) has been to protect the front spar in the event of a failure of engine mounting.

2)Linkages and ' fuse' pins are located such that in case of mounting failure ( in flight ) , the thrust of the engine will pivot it up and over the major wing structure before total detachment IF still generating thrust.

SO IMHO- the engine at the time of impact was at a high ( max? ) thrust level such that the impact failed at least part of the pivot linkage, allowing the engine to pivot up and over the front spar, thus one sees the engine above the wing facing aft but still partially attached to the wing.

LEM 3rd Aug 2016 18:34

Bounced landing
 
I believe this accident will demonstrate that checking for a positive rate of climb after a bounced landing is NOT enough of a condition to raise the gear.
Ironically, when they raised the gear, there actually was a positive rate.... After the bounce.

There must be a second condition: full thrust obtained by the engines, not just TOGA selected but with engines not spooled up!

But... a pilot should know this instinctively.

Julio747 3rd Aug 2016 18:39

Rubbish!
 

Originally Posted by DaveReidUK (Post 9461137)
Just when we thought the SQ debate had run its course and there was nothing new that could usefully be added ...

Heaven forbid that the respective investigations - EK and SQ - should both conclude that the crew in question made the correct decision in the (significantly different) circumstances.

Sorry Dave. Different circumstances, I will grant you. But...

EQ... Immediate evac, history shows a good call.

SQ... No evac. History tells us they all survived. By the skin of their teeth, perhaps? But that doesn't make it a good call in my book.

At least we can agree on a happy ending for SQ. Alas not for EQ, with the death of a firefighter.

I have no doubt that if SQ had evacuated, they all would have survived. And would have been at much lower risk....

This is not a game of hindsight. We are in the business of minimising risk.

E_S_P 3rd Aug 2016 18:42

oldoberon

you would believe what is around it, all that sand and they build up to the edge of the airfield

I seem to remember back in the late 70's, early 80's it was mainly sand around the airport, its just the manic expansion of Dubai which has made it as it is today :ok:

MrSnuggles 3rd Aug 2016 18:47

Re: Locked overhead bins.

Li-Ion batteries create their own oxygen in case of fire. Absolutely insane to think it is a good idea to "lock them in there to not create chaos in the cabin". They need to be removed ASAP and put in a container of water. Don't fool around with that stuff, or you'll have created a much larger chaos for the relatives.

Pontius Navigator 3rd Aug 2016 18:48

Cabin Luggage

If my bag is under my seat I might pull it out to clear my exit and keep hold.

If the locker bursts open I might grab my bag to keep the exit clear and keep hold.

I certainly would not open locker and pull my luggage out.

Julio747 3rd Aug 2016 18:50

Not sure I believe this happened...
 

Originally Posted by LEM (Post 9461154)
I believe this accident will demonstrate that checking for a positive rate of climb after a bounced landing is NOT enough of a condition to raise the gear.
Ironically, when they raised the gear, there actually was a positive rate.... After the bounce.

There must be a second condition: full thrust obtained by the engines, not just TOGA selected but with engines not spooled up!

But... a pilot should know this instinctively.

Nothing wrong with your logic. But I think the probability that this happened is very low indeed. This is not a tiger moth landing....

But bouncing... Positive rate of climb... Engines not spooled up enough.... No. Sorry. He would have put it down, surely?

Are you suggesting he got a GA command half way through a bounce???? Nonsense....

I admit I have no idea what happened here, but that seems farfetched...

Banana4321 3rd Aug 2016 18:50

All these people talking about what they would do in the event of an evac and they haven't got the first idea of how they would react. Perhaps best to not guess eh? It isn't what this thread is about.

Dopsonj 3rd Aug 2016 18:56

https://www.youtube.com/watch?v=5YxCyeaOVOU

Video from INSIDE the plane during evac....

Julio747 3rd Aug 2016 18:59

Create their own oxygen????
 

Originally Posted by MrSnuggles (Post 9461164)
Re: Locked overhead bins.

Li-Ion batteries create their own oxygen in case of fire. Absolutely insane to think it is a good idea to "lock them in there to not create chaos in the cabin". They need to be removed ASAP and put in a container of water. Don't fool around with that stuff, or you'll have created a much larger chaos for the relatives.

Lithium ion batteries have their issues. But "creating their own oxygen" is only something God (and maybe plants) can do!

You might want to revisit some basic chemistry....

They do, however, contain a lot of energy that can cause a problem, even in the absence of oxygen... Is that what you meant?

suninmyeyes 3rd Aug 2016 19:02

Newfoundglory you wrote

Could wheels up have been the best outcome for this though? IIRC the BA 777 at LHR had a massive fuel leak because the landing gear punctured the fuel tanks when it crashed?

The fuel tanks were not punctured in the LHR accident. Fuel was coming out through the fuel pipes to the engines. If you are crashing on land it is always best to have the gear down. If the gear breaks off it cushions the impact. We are taught that it is even better to have just one undercarriage leg down even a strut with no wheels on it (that would make a real mess of the runway) than to land totally gear up. If the gear had been down on this aircraft the likely possibilities would have been:


1) It stayed on the ground and would have been brought to a stop.
2) It touched the ground and bounced into the air and climbed away.


I cannot think of any situation in a windshear incident close to the ground where it is better to have the gear up than down. I remember an incident at LHR many years ago when a Trident landing on 23 hit strong windshear at 100 feet and tried to goaorund. The Captain raised the nose and put on power which came on just as the plane touched down quite smoothly, the Captain elected to close the throttles and stayed on the ground.

Obba 3rd Aug 2016 19:02

Dopsonj's link at 1:20 shows engine on fire...

expurser 3rd Aug 2016 19:03


oldoberon
Quote:
you would believe what is around it, all that sand and they build up to the edge of the airfield. I seem to remember back in the late 70's, early 80's it was mainly sand around the airport,
Me too. Great job by the Cabin Crew

oldchina 3rd Aug 2016 19:05

Video from INSIDE the plane during evac ...
 
I'd rather be in a "panic" of Singaporeans ...

obrock 3rd Aug 2016 19:06

Evac video
 
in that evac video you may observeral things:

- like a rushed normnal deboarding...almost everyone grabs his hand luggage... strangely you donīt hear any CC voices at that time... usually they are very loud, but maybe they had to do with
- the decision which exits to use: the left hand side seemd not to be good due to the strong wind on it, at least one slide is visibly not usable due to that wind
- at 2:09 you can see the position of the flaps... looks like 30 to me, but I am unsure, also you can see a little fire under engine no 1... I guess the later explosion was on the right

Deep and fast 3rd Aug 2016 19:14

Any info on crew experience? Training flight?

HEMS driver 3rd Aug 2016 19:18


Apologies for missing this, if it is already here on this thread, but where can that ATC recording be found?
http://archive-server.liveatc.net/om...2016-0830Z.mp3

LaminerFlow 3rd Aug 2016 19:19

Speculation induced Fatigue and complacency?
 
The possible causal factors are enormous. Was it the aircraft or the crew? History has taught us that it could be either.
From the very little evidence available it is unfair to cast aspersions about who may be responsible but it is going to be discussed anyway so is best to be non judgmental.
From where the impact occurred, if a go around was initiated at a low altitude my guess would be a fairly rapid loss of performance. If the aircraft is innocent then it is probably environmental or crew. The weather does not look that bad.
The most likely way to cause a large performance loss that the pilot flying and the aircraft can not recover from is to retract the flaps more than the procedures call for.
This has caused accidents in the past and has been the focus of much training world wide including in EK.
It still happens today during takeoff and go around through fatigue and or complacency. Aircraft performance on a good day is enough to cope with these slip ups, hot or high altitude or mild wind shear combined with retracting too much flap to early would cause an aircraft to hit the ground in the same region as EK521. The crew most likely would not even know they did it.
In a complacent state crew operate on the most likely automatic response expected without conscious thought.
After the landing configuration is attained the PM is programmed by routine that the next time the flags need to be moved is during the complete retraction after landing. In a fatigued or complacent state the call for flaps during a go around could initiate a greater flap retraction than desired.

Aerostar6 3rd Aug 2016 19:19

Evacuation video.
It has been said before, but under stress humans revert to a known pattern.
These guys were getting off an aircraft - which means you open the locker, get your bag and head for the exit, which is what they were doing.
The lack of smoke/fire (initially) meant that there was no real impetus to get off.
Even the landing itself may not have seemed unusual to infrequent flyers.
I flew with the rear cabin crew member on the BA Beijing 777 which pancaked at LHR.
Even she, as a seasoned cabin crew member was flabbergasted to see the aircraft on its belly having evaded, having experienced more violent "normal" landings before.
Probably compounded by mostly none English speaking Indian nationals, which meant that any cabin crew exhortations were not understood.
Don't blame people for being human.

vlkyplky 3rd Aug 2016 19:31


Originally Posted by Dopsonj (Post 9461176)
https://www.youtube.com/watch?v=5YxCyeaOVOU

Video from INSIDE the plane during evac....

Thank you for this. Could be used for CC training purposes


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