Anyone else seen the pics,and video, of the AF A380 with an uncontained engine failure landing safely at Goose Bay? Happened over the Atlantic, with two hours flying time to GBay, and picked up by myself on pPrune this evening
Hope the passengers got free drinks!
Last edited by: legacylad on Sat 30 Sep 17 at 20:24
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Not much luck with engines on Airbus A380s
en.wikipedia.org/wiki/Qantas_Flight_32
That's two from a fleet of about 125 I think.
Mind you, the first engine was a Rolls Royce.
I suppose you are doing well if you log the same number of landings as takeoffs!
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RR issues on A380s were solved years ago now. AF use Engine Alliance engines.
At least it was a four engined aircraft, I have always been a little nervous flying across the Atlantic in a twin engjned aircraft (777, A330, 767), if one engine were to fail two hours from a suitable airport you are running on quite small safety margins.
Goose Bay has been equipped for large airliners for many years.
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Double engine failures are very rare, for any reason. The A380 is in a bit of a class of its own size wise so no doubt there was a bit of a faff while they sorted some steps out.
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>> Double engine failures are very rare, for any reason.
>>
If my aircraft has only two engines, then I would like double engine failure to be unknown, rather than just rare.
Just thinking, like.
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I can't think of any of the top of my head, not from an actual engine fault as opposed to something external such as fuel starvation or bird strike causing the engines to fail.
Unknown enough? ;-)
Last edited by: sooty123 on Sun 1 Oct 17 at 08:14
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>> I can't think of any of the top of my head, not from an actual
>> engine fault as opposed to something external such as fuel starvation or bird strike causing
>> the engines to fail.
>>
>> Unknown enough? ;-)
>>
Wasn't the Quantas one a fault with an oil pipe?
The crash of a BA jet at Heathrow was fuel starvation, but due to an engine design fault (ice blocking the fuel flow because engine oil wasn't heating it properly).
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Wasn't the Quantas one a fault with an oil pipe?
it was iirc, yes.
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>> The crash of a BA jet at Heathrow was fuel starvation, but due to an
>> engine design fault (ice blocking the fuel flow because engine oil wasn't heating it properly).
Yes, it was fuel starvation.
Still, like I said, very much unknown/very rare to have a double engine failure outside fuel starvation or bird strike.
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The Gimli Glider was human error, calculating fuel requirements in imperial and loading it in metric.
It's an intetesting story, worth Googling, the 767 involved served another 25 or 30 years after the event.
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>> The Gimli Glider was human error, calculating fuel requirements in imperial and loading it in
>> metric.
Several other factors involved. Fuel was loaded by volume and converted to weight for load/trim purposes - imperial/metric mix up was conversion factor used in that calculation.
Both fuel tank contents gauge systems were u/s (or at least appeared to be). Aircraft should not have taken off under those conditions as minimum equipment list required one system to be operative but crew believed they had a dispensation. They also had the tank contents checked with a dipstick but misinterpreted result of that in a way that showed what they expected ie sufficient fuel for transcontinental flight to Edmonton.
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>> I can't think of any of the top of my head, not from an actual
>> engine fault as opposed to something external such as fuel starvation or bird strike causing
>> the engines to fail.
List of multiple engine failures requiring gliding on Wiki:
en.wikipedia.org/wiki/List_of_airline_flights_that_required_gliding
On a quick scan all either ingestion of ice, water or other foreign object OR fuel exhaustion/mishandling of fuel by crew or contamination of fuel. One of them, and there are other isolated similar examples, involved maintenance failures resulting in loss of lubricating oil from multiple engines. BA A320 losing engine cowlings at Heathrow was similar.
The AF one is clearly far worse than loss of cowlings suggested in early reports. Looks as if entire fan has departed from front of engine forward of turbine. Possibly a fatigue or a lubrication failure?
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> Looks as if entire fan has departed from front of engine forward of turbine. Possibly
>> a fatigue or a lubrication failure?
>>
The whole LP compressor has gone, if you look at some of the pictures you see part of it is still connected to the LP shaft. I can't quite see if the main nut is still there but I think it is.
I suspect fatigue failure even in cases of oil starvation normally it'll just wind down even if the LP shaft seizes solid. Be interesting to see what the report says.
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Another twin engine failure was the Hudson River A320 landing that made a celebrity of the captain Casey Sullenburger and lead to a movie featuring the event.
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>> Another twin engine failure was the Hudson River A320 landing that made a celebrity of
>> the captain Casey Sullenburger and lead to a movie featuring the event.
Birds again. I suppose it's possible a 4 engine might have only lost two but still a significant emergency.
If this one is thought to be fatigue then there will be grounding and/or a rigorous examination routine. Will be interesting to see if this engine was high hours or, conversely, whether it had recent maintenance history around the fan and/or LP compressor.
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Will be interesting to see if this engine was high hours or,
>> conversely, whether it had recent maintenance history around the fan and/or LP compressor.
>>
Not much you can do with it whilst it's on the wing. Last overhaul might bring some answers.
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You don't get bird strikes at 35000 feet. Effectively the issue is what are the chances of both engines failing as a result of mechanical failure within an hour or two of one another. Statistically virtually nil I would say.
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>> You don't get bird strikes at 35000 feet.
Not unknown at 30 thousand plus but tends to be single birds of specific species not flocks:
www.pprune.org/tech-log/347095-high-level-bird-strike.html
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Lucky it wasn't an inner engine because the outer engine may have ingested some debris resulting in the loss of two engines.
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This is one incident involving uncontained engine failure, the cause being an impurity in the material used in manufacture despite the failure being when the engine was 18 years old and have flown for many thousands of hours.
en.wikipedia.org/wiki/United_Airlines_Flight_232
Last edited by: Hard Cheese on Sun 1 Oct 17 at 14:51
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>> Lucky it wasn't an inner engine because the outer engine may have ingested some debris
>> resulting in the loss of two engines.
Ingesting debris is the least of your worries. If the blade hub bits break off the shaft it can cut through the wing or the main body.
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>> it can cut through the wing or the main body.
This happened on a "flight" featured recently on TV, A blade from a Turbo-prop engine sheared and stuck through the fuselage window, just missing a female passengers head by a "claimed" 2inches!
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I would expect that a detached rapidly rotating fan would make an effective saw and make short work of any part of the airframe it hit.
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>> >> Lucky it wasn't an inner engine because the outer engine may have ingested some
>> debris
>> >> resulting in the loss of two engines.
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>> Ingesting debris is the least of your worries. If the blade hub bits break off
>> the shaft it can cut through the wing or the main body.
>>
It can, though the direction of the fuselage is small part of the arc that it may travel in, and at 500mph plus it will be taken rapidly backwards (not so if on take off though with the combination of low speed and max power). However if the inner engine fails it only needs a small piece of debris to enter the outer engine and you have two of them U/S resulting in asymmetric thrust.
Last edited by: Hard Cheese on Sun 1 Oct 17 at 18:19
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>> It can, though the direction of the fuselage is small part of the arc that
>> it may travel in, and at 500mph plus it will be taken rapidly backwards
Actually it won't, the gyroscopic effect and directional mass and momentum means it will go sideways. Now that could be up down left or right. Down is good, up is bad left or right could be good or bad!
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>>
>> >> It can, though the direction of the fuselage is small part of the arc
>> that
>> >> it may travel in, and at 500mph plus it will be taken rapidly backwards
>>
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>> Actually it won't, the gyroscopic effect and directional mass and momentum means it will go sideways. Now that could be up down left or right. Down is good, up is bad left or right could be good or bad!
>>
That doesn't make a lot of sense Z - the RPM of the main LP fan is not as high as you would think. Fragments may go side ways and fuselage damage is possible, though unlikely from the outer engine. As I say at 500mph plus most debris will go backwards and damage the wing and pylon in the area around the engine as is evident in the pictures.
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> That doesn't make a lot of sense Z - the RPM of the main LP
>> fan is not as high as you would think.
How fast do you think they turn at?
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>> How fast do you think they turn at?
>>
I note the word "think" kind of implying that I might think that they turn at a speed that differs from reality.
The LP turbines in high bypass gas turbines spin at around 2500 to 4000 rpm upon take off though are running more slowly at cruise - unless you would like to advise to the contrary?
Of course the HP stage spins much faster though that's not what failed in this instance AFAIAA.
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>> Of course the HP stage spins much faster though that's not what failed in this
>> instance AFAIAA.
As the stages are all on the same shaft they all spin at the same speed.
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>> Of course the HP stage spins much faster though that's not what failed in
>> this instance AFAIAA.
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>> As the stages are all on the same shaft they all spin at the same
>> speed.
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Z, they are not on the same shaft, you don't understand the principals of a high bypass turbofan engine it seems.
i.stack.imgur.com/Y7wB2.png
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>> Z, they are not on the same shaft, you don't understand the principals of a
>> high bypass turbofan engine it seems.
>>
>> i.stack.imgur.com/Y7wB2.png
The GP7200 that exploded is NOT a geared turbofan.
Last edited by: VxFan on Tue 3 Oct 17 at 01:34
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>> The GP7200 that exploded is NOT a geared turbofan.
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The LP and HP turbines are on different shafts Z.
A geared turbo fan enables the large bypass fan and the LP shaft to run a different speeds.
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As I say at 500mph
>> plus most debris will go backwards
You are wrong.
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>> You are wrong.
>>
Hmm ...
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>>As I say at 500mph plus most debris will go backwards
I think you're forgetting that both the plane and the debris are travelling at 500mph. So the debris will only go backwards as fast as it decelerates from 500mph. And obviously it will decelerate, but surely not very much in the slightly less than one second that it will take it to shoot out the side and hit the fuselage.
Also, the plane would only be pulling away from the debris as the debris loses speed. Now, given that the engine has gone bang with a resulant loss in power, will the debris lose speed faster than the entire plane?
I reckon that its a fair bet that in relation to the plane itself, the debris won't go backwards much, if at all.
[or I still haven't had enough caffeine and have got my head on wrong]
Last edited by: No FM2R on Mon 2 Oct 17 at 16:52
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>> >>As I say at 500mph plus most debris will go backwards
>>
>> I think you're forgetting that both the plane and the debris are travelling at 500mph.
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Much more reasoned arguments than Z ;-), much better to discuss.
Even if the plane lost half of it's power it would still be under power and in the second or so that it would take the debris to disperse would lose very little altitude or speed, and of course it's pretty aerodynamic. Whereas the debris from the engine would be very un-aerodynamic. If you could hold something like a golf ball in the airflow at 500mph and let go of it, it would disappear backwards in the blink of an eye with hardly any evidence of any drop. After all even it's terminal velocity (it's max speed when falling) will be only 100mph ish, only 1/5 of the plane's forward speed.
EDIT: Just Googled and it is suggested in two sources that the terminal velocity of a golf ball is around 74 mph.
Last edited by: Hard Cheese on Mon 2 Oct 17 at 17:29
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>> If you could hold something like a golf ball in the airflow at 500mph and let go of it
Not done that, but I have dropped a tennis ball out of a train window. (I know, I was young).
Ok, so that was a rural train probably batting along at 60mph. But the ball didn't fall behind as fast as you'd think and was most certainly still close when it hit the floor. Even your golf ball example, it wouldn't disappear in a blink, there would seem to be a brief be a pause as it started to lose speed and then it would accelerate away from you very quickly.
So I reckon with the speed that debris is coming out of the engine at, its existing momentum, and with a darn sight less wind resistance than the plane, I stand by my first thought;
In the split second available, it just isn't going to fall behind much and it certainly isn't go to disappear in a flash. I reckon two rows back and your a*** is screwed.
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Googling there are very few examples of the fuselage being damaged by uncontained engine failure, most are at take off when the engine is flat out and the airspeed is low.
This was at 31000 feet though in the climb so the engine was working hard, it's 737 so a twin and the engine is much closer to the fuselage than the AF A380, though a similar failure it seems, the fuselage sustained some damage it seems above and behind the damaged area of the engine (the debris probably bounced over the wing root) though the passenger cabin was not penetrated.
www.nydailynews.com/news/national/southwest-airlines-plane-lands-fla-engine-malfunction-article-1.2768491
Last edited by: Hard Cheese on Mon 2 Oct 17 at 18:13
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Essentially then, if I may summarise, sideways not backwards.
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>> In the split second available, it just isn't going to fall behind much and it
>> certainly isn't go to disappear in a flash. I reckon two rows back and your
>> a*** is screwed.
I always sit in the row one of first class, so the chaos will miss me.
Doesn't everybody sit in first class?
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>> Much more reasoned arguments than Z ;-),
What better than science and physics you mean?
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>>
>> >> Much more reasoned arguments than Z ;-),
>>
>> What better than science and physics you mean?
>>
That wouldn't be difficult ;-)
Though what I meant was discussion with reasoning rather than statements such as 'you're wrong'.
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OK I'll qualify that .
You do not get bird strikes at 35,000 feet over the North Atlantic Ocean.
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>> You do not get bird strikes at 35,000 feet over the North Atlantic Ocean.
Given that one of the 'at altitude' species is Canada Geese I'd not absolutely exclude birds at high latitudes. I accept though that fowl are unlikely in extant case.
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Monarch is looking a bit of a dodgy prospect.
www.dailymail.co.uk/news/article-4937918/Jets-place-rescue-100-000-stranded-passengers.html
I was talking with a friend who works in a travel agents on Saturday, the Ryanair problems have caused them huge problems, as much from worried unaffected customers than those effected. They tied up huge amounts of staff time.
Last edited by: Old Navy on Sun 1 Oct 17 at 20:33
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Geese tend to migrate North South or vice Vera rather than West East. Canadia Geese you see in the U.K. arw mostly resident all the year round and are descendants of escaped birds introduces to various parks in the last century.
I don't think in any case they can reach anywhere near 35,000 feet. The few birds that do attain such heights mostly have migration route across the Himalayas. At that sort of height they need a metabolism adapted to a very rarified atmosphere. Most creatures including us would be dead within minutes in that environment.
Last edited by: CGNorwich on Sun 1 Oct 17 at 20:46
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First Ryanair probs, now AF - sooty123
