Air France flight loses an engine over the Atlantic

eg2505

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#42
now the million dollar question,

if this same thing had happened on a twinjet? (smaller flying Peugeot)

like a A330/A320 or a 767/757 or even a newfangled A350...

seems there is still a good reason ultra long haul is with a 4 engine plane...
 

Ockie

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#43
now the million dollar question,

if this same thing had happened on a twinjet? (smaller flying Peugeot)

like a A330/A320 or a 767/757 or even a newfangled A350...

seems there is still a good reason ultra long haul is with a 4 engine plane...
The engines on twin jets are specifically designed to be overpowered in case something like this happens. If a engine fails on take off, the twin jet needs to be able to climb out of a airport and up to a safe altitude on one engine. A twin jet can fly relatively safely with just one engine until it can reach a safe airport to land at. That is where ETOPS comes in also.
 

ponder

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#44
now the million dollar question,

if this same thing had happened on a twinjet? (smaller flying Peugeot)

like a A330/A320 or a 767/757 or even a newfangled A350...

seems there is still a good reason ultra long haul is with a 4 engine plane...
It's fine.
 

kab123

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#45
now the million dollar question,

if this same thing had happened on a twinjet? (smaller flying Peugeot)

like a A330/A320 or a 767/757 or even a newfangled A350...

seems there is still a good reason ultra long haul is with a 4 engine plane...
Always book on a aircraft with a GE90-115B!
 

eg2505

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#46
The engines on twin jets are specifically designed to be overpowered in case something like this happens. If a engine fails on take off, the twin jet needs to be able to climb out of a airport and up to a safe altitude on one engine. A twin jet can fly relatively safely with just one engine until it can reach a safe airport to land at. That is where ETOPS comes in also.
fair enough, but what if the engine cant operate at that power setting for long?
how controllable is it with only 2 engines.....

I mean I know dual failure is extremely rare, and its only ever happened 4 times,

but wont you feel better when there are another 3 engines to take over?

I mean its kind of like having a blow out in a car with 4 tires vs a motorcycle with only 2.
sure an accident can happen with either, but its more controllable with 4 engines vs 2,

but thats one theory at least...
 

Ockie

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#47
fair enough, but what if the engine cant operate at that power setting for long?
how controllable is it with only 2 engines.....
Again, that is where ETOPS comes in. I believe the Airbus A350 has the highest rating to date with ETOPS-370. Pretty much means that the airliner is allowed to fly a route where at any given time, it is a maximum travel time of 370 minutes away from a suitable airport to land should a engine fail. So, basically, the airliner can fly on one engine at normal operating speed for 370 minutes. Turbofans are so reliable these days, that the chances of both failing is really really small. Chances of something else taking down the airliner is much more I would guess. With fly by wire and all the computerised avionics controlling the aircraft, that is not really a concern, unless debris from a uncontained engine failure damages control surfaces on the wing or damages the actual fuselage and causes a decompression.

Are you a nervous flyer?
 

ForceFate

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#48
fair enough, but what if the engine cant operate at that power setting for long?
how controllable is it with only 2 engines.....

I mean I know dual failure is extremely rare, and its only ever happened 4 times,

but wont you feel better when there are another 3 engines to take over?

I mean its kind of like having a blow out in a car with 4 tires vs a motorcycle with only 2.
sure an accident can happen with either, but its more controllable with 4 engines vs 2,

but thats one theory at least...
There has been 4 engine failure before.

If structural integrity of isn't compromised, you're almost guaranteed a normal landing with one engine
 
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kab123

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#49
There has been 4 engine failure before.

If structural integrity of isn't compromised, you're almost guaranteed a normal landing with one engine
you are off course, on a statistical level, quite correct.

4 engine failure are less likely than 2 engine failure.

And if I'm placed in a actual situation like this, my mind will probably also be more at peace knowing the are 3 extras...

Both however, are EXTREMELY unlikely. So the difference between the two is negligible.

On a practical level, what's the difference between 1 in a million or 2 in a million?

Or like you say, there has never been a 4 engine failure. But there has been 4, 2 engine failures.

Taking into consideration the billions of hours of accumulated flight time over the decades, what's the difference between the two?

You are more likely to crash due to some other reason..
 
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Gordon_R

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#50
you are off course, on a statistical level, quite correct.

4 engine failure are less likely than 2 engine failure.
Or running out of fuel due to punctured tanks. That would be a terminal event...

Failure of an engine means dropping to a lower altitude, and the calculations for fuel margin and alternate airports are complex.

The most risky routes would be in the Southern Hemisphere over the Antarctic, but no airlines currently fly those city pairs. For example, Cape Town, SA to Auckland, NZ would be a worst case scenario: https://www.travelmath.com/flying-distance/from/Cape+Town,+South+Africa/to/Auckland,+New+Zealand
 

Sinbad

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#51
you are off course, on a statistical level, quite correct.

4 engine failure are less likely than 2 engine failure.

And if I'm placed in a actual situation like this, my mind will probably also be more at peace knowing the are 3 extras...

Both however, are EXTREMELY unlikely. So the difference between the two is negligible.

On a practical level, what's the difference between 1 in a million or 2 in a million?

Or like you say, there has never been a 4 engine failure. But there has been 4, 2 engine failures.

Taking into consideration the billions of hours of accumulated flight time over the decades, what's the difference between the two?

You are more likely to crash due to some other reason..
haha this brings this to mind:

A statistic professor plans to travel to a conference by plane. When he passes the security check, they discover a bomb in his carry-on-baggage. Of course, he is hauled off immediately for interrogation.
"I don't understand it!" the interrogating officer exclaims. "You're an accomplished professional, a caring family man, a pillar of your parish - and now you want to destroy that all by blowing up an airplane!"
"Sorry", the professor interrupts him. "I had never intended to blow up the plane."
"So, for what reason else did you try to bring a bomb on board?!"
"Let me explain. Statistics shows that the probability of a bomb being on an airplane is 1/1000. That's quite high if you think about it - so high that I wouldn't have any peace of mind on a flight."
"And what does this have to do with you bringing a bomb on board of a plane?"
"You see, since the probability of one bomb being on my plane is 1/1000, the chance that there are two bombs is 1/1000000. If I already bring one, the chance of another bomb being around is actually 1/1000000, and I am much safer..."
 

Arthur

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#52
haha this brings this to mind:

A statistic professor plans to travel to a conference by plane. When he passes the security check, they discover a bomb in his carry-on-baggage. Of course, he is hauled off immediately for interrogation.
"I don't understand it!" the interrogating officer exclaims. "You're an accomplished professional, a caring family man, a pillar of your parish - and now you want to destroy that all by blowing up an airplane!"
"Sorry", the professor interrupts him. "I had never intended to blow up the plane."
"So, for what reason else did you try to bring a bomb on board?!"
"Let me explain. Statistics shows that the probability of a bomb being on an airplane is 1/1000. That's quite high if you think about it - so high that I wouldn't have any peace of mind on a flight."
"And what does this have to do with you bringing a bomb on board of a plane?"
"You see, since the probability of one bomb being on my plane is 1/1000, the chance that there are two bombs is 1/1000000. If I already bring one, the chance of another bomb being around is actually 1/1000000, and I am much safer..."
Love it. Thanks. :D
 

Billy

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#53
'On 24 June 1982, the route was flown by the City of Edinburgh, a 747-236B. The aircraft flew into a cloud of volcanic ash thrown up by the eruption of Mount Galunggung (approximately 180 kilometres (110 mi) south-east of Jakarta, Indonesia), resulting in the failure of all four engines."

https://en.wikipedia.org/wiki/British_Airways_Flight_9

Any other examples of a four engine failure and the aircraft landing safely?
 

neilronaldson

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#54
Same thing happened to us going to new zealand....on a new zealand airline - also bang and a shudder (fan went through the engine) and then the captain came on and said dont worry we dumping fuel and landing....landed with ALOT of fire engines and ambulances waiting for us.

We had just taken off and levelled out when it happened.
 

Sinbad

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#55
Same thing happened to us going to new zealand....on a new zealand airline - also bang and a shudder (fan went through the engine) and then the captain came on and said dont worry we dumping fuel and landing....landed with ALOT of fire engines and ambulances waiting for us.

We had just taken off and levelled out when it happened.
Bird strike?
 

Kelerei

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#57
The most risky routes would be in the Southern Hemisphere over the Antarctic, but no airlines currently fly those city pairs. For example, Cape Town, SA to Auckland, NZ would be a worst case scenario: https://www.travelmath.com/flying-distance/from/Cape+Town,+South+Africa/to/Auckland,+New+Zealand
QF63 (Sydney to Johannesburg) often routes fairly close to the Antarctic coastline to avoid significant prevailing headwinds. (The return flight, QF64, follows a more northerly routing to take advantage of said winds).

Owing to the remoteness of the Sydney to Johannesburg route, Qantas still utilizes 747s on the route: this is significant when one considers that Qantas is seeking to remove the 747 from their fleet.
 

eg2505

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#60
Are you a nervous flyer?
not at all, Im actually obsessed with flying and aviation in a big way......

but always worries me when things like this happen due to automation and computerization,
as many things that are rare can happen on a plane, and 1 in a billion chance can suddenly happen.

yes I know its not probable, and I know how far pilots train, but black swan can happen.
and then you never know.
 
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