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[Rods2]

Could have been much worse as it is always a very serious matter when any engine turbine failure is not contained by the engine casing.

http://www.dailymail.co.uk/news/article-4936802/Air-France-jet-loses-engine-cover-SIX-MILES-high.html

[LC0112G]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

[Doctor Gollum]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

Seconded, and actually of limited significance to a safe landing as the outboard engines have no thrust reverser function.

Lucky it didn't damage the wing in the process though

[Lizzie Zoom]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

Yes, and it is a miracle that none of the debris exiting at tremendous velocity never apparently entered the wings or fuselage with all that would entail.  Frightening indeed.

[Doctor Gollum]

Given that that engine is around 70ft from the fuselage and would have jammed in the intake cowl with the resulting force shearing the few bolts that attach the intake cowl to the rest of the engine assembly, you've better odds of winning yesterdays lottery than any of the front fan actually reaching the fuselage

Given the altitude and time of year, a goose or two have probably missed Thanksgiving...

https://youtu.be/j973645y5AA

[Rods2]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

Agree that this complete fan failure is uncontainable, but due to potential catastrophic peripheral damage, it is as I said a very serious incident that they got away with. Part of engine certification is a simulated bird strike and if the damaged turbine(s) aren't contained the test is failed and the engine is not certified.

[grifter]

I'd read that the force of a blade at full speed is the same weight as a locomtive, doesn't bear thinking about, although i just did!

[Doctor Gollum]

The 'fan' shown here to the right of the two blokes is the one visible in photos from yesterday's event...



... And is actually fixed

[Doctor Gollum]

http://www.pprune.org/rumours-news/600170-af66-cdg-lax-diverts-uncontained-engine-failure-over-atlantic-2.html

[Sir Tigger KC]

Wouldn't have wanted to have been on the cabin cleaning crew after that.  Imagine the smelly seats!   

[Lizzie Zoom]

Given that that engine is around 70ft from the fuselage and would have jammed in the intake cowl with the resulting force shearing the few bolts that attach the intake cowl to the rest of the engine assembly, you've better odds of winning yesterdays lottery than any of the front fan actually reaching the fuselage

Given the altitude and time of year, a goose or two have probably missed Thanksgiving...

https://youtu.be/j973645y5AA

But it COULD have happened.  It is NOT impossible

[Doctor Gollum]

Impossible is your word, not mine... unlikely was what I implied...

Suspected fan hub failure, and as suggested in my last link fan would have actually gone forward with the sudden release of load on it... snagging the cowling as it went and shearing it off. Whole lump would haved passed cleanly below the rest of the engine and consequently well down and away from either the wing or fuselage.

At cruising speed, any uncontained failure would have ended up hitting the wing outboard of the number three engine. The apparent damage to the leading and trailing edges is minimal, with flaps and slats functioning correctly (as demonstrated by the video of the descent and landing ) suggesting that the cowling and fan lodged within it broke off relatively cleanly.

The failure of this engine is very different in nature to the Qantas one which was genuinely an uncontained failure and being the inboard engine meant that the fuselage was potentially in the firing line.

[LC0112G]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

Agree that this complete fan failure is uncontainable, but due to potential catastrophic peripheral damage, it is as I said a very serious incident that they got away with. Part of engine certification is a simulated bird strike and if the damaged turbine(s) aren't contained the test is failed and the engine is not certified.

Yes testing does involve firing frozen birds (chicken/geese) into engines. It also involves explosively detonating a small charge so that a blade (intentionally) becomes detached, and the casing must contain the blade, and the rest of the fan and engine should remain more or less where it is.

However, complete fan disks aren't tested to see what happens when they detach because, quite simply, it shouldn't/mustn't happen because if it does happen it's always uncontainable. If a fan disk becomes detached it shoots forwards at an incredible speed, taking the cowling with it. The fan is providing getting on for one quarter of the thrust required to get an A380 into the air via a shaft, and if that shaft breaks the thrust forces the fan forwards.  It then falls to earth still spinning like a demented Flymo. If it hits the ground in a populated area (say Winsor or Slough) it's got a high chance of killing people.

Fan blades break off relatively often. Fan disk failures are thankfully very rare - and smelly stuff will be hitting the air circulation system in Engine Alliance till they work out what went wrong. I expect everyone using that type of engine is doing a quick check of the fan stage today. If others find faults then you could end up with half the worlds A380's (the half not using Rolls Royce engines) grounded.

Another issue is the broken A380. There won't be any existing facilities for fixing it at Goose, and there isn't a hangar big enough to get it in there either. It gets a bit parky there in winter, and the chances of this plane being fixed anytime soon (before Christmas) appear small to me. The Qantas plane was "lucky" in that it landed back at Singapore, which is an A380 and other aircraft maintainance centre, and in a warm (if rainy) location. Goose. Brrrrr. 

[Rods2]

Engine casings are neither designed nor expected to contain complete turbine failure. This is where the whole disk containing dozens of turbine blades breaks free. Doing so is virtually impossible due to the energy involved.

Engine casings are designed to contain turbine blade failures. This is where a single (or occasionally multiple) blade(s) from the turbine breaks free from the turbine disk. The mass of a single blade is only a fraction of that of the whole disk, and so this can (and should) be contained.

This incident looks like the fan blade disk completely detached. Completely uncontainable by any system.

Agree that this complete fan failure is uncontainable, but due to potential catastrophic peripheral damage, it is as I said a very serious incident that they got away with. Part of engine certification is a simulated bird strike and if the damaged turbine(s) aren't contained the test is failed and the engine is not certified.

Yes testing does involve firing frozen birds (chicken/geese) into engines. It also involves explosively detonating a small charge so that a blade (intentionally) becomes detached, and the casing must contain the blade, and the rest of the fan and engine should remain more or less where it is.

However, complete fan disks aren't tested to see what happens when they detach because, quite simply, it shouldn't/mustn't happen because if it does happen it's always uncontainable. If a fan disk becomes detached it shoots forwards at an incredible speed, taking the cowling with it. The fan is providing getting on for one quarter of the thrust required to get an A380 into the air via a shaft, and if that shaft breaks the thrust forces the fan forwards.  It then falls to earth still spinning like a demented Flymo. If it hits the ground in a populated area (say Winsor or Slough) it's got a high chance of killing people.

Fan blades break off relatively often. Fan disk failures are thankfully very rare - and smelly stuff will be hitting the air circulation system in Engine Alliance till they work out what went wrong. I expect everyone using that type of engine is doing a quick check of the fan stage today. If others find faults then you could end up with half the worlds A380's (the half not using Rolls Royce engines) grounded.

Another issue is the broken A380. There won't be any existing facilities for fixing it at Goose, and there isn't a hangar big enough to get it in there either. It gets a bit parky there in winter, and the chances of this plane being fixed anytime soon (before Christmas) appear small to me. The Qantas plane was "lucky" in that it landed back at Singapore, which is an A380 and other aircraft maintainance centre, and in a warm (if rainy) location. Goose. Brrrrr.

My dad was a Senior Engine Test Controller at National Gas Turbine Establishment, Farnborough which meant during my childhood I got to learn a reasonable amount about jet engines, their testing and certification and also various problems during development testing when it was a joint effort between Rolls Royce and NGTE in solving some of the problems. They were also involved with Sea King icing tests after several were lost due to ice ingestion into the engines. Much of the testing during the winter was done in the evening after the evening peak for electricity where the air house for generating the air stream would use up to 132MW of power.

[Entwood]

(big snip)

Another issue is the broken A380. There won't be any existing facilities for fixing it at Goose, and there isn't a hangar big enough to get it in there either. It gets a bit parky there in winter, and the chances of this plane being fixed anytime soon (before Christmas) appear small to me. The Qantas plane was "lucky" in that it landed back at Singapore, which is an A380 and other aircraft maintainance centre, and in a warm (if rainy) location. Goose. Brrrrr.

Perhaps in a month or two .. not too bad right now , however the maintenance guys fixing it will have some recompense ... I can recommend (wishes he had a "tongue in cheek" smiley) the delights of "Happy Valley"  (if any of these are still operating that is ....    )

Trappers, ....  not much in the way of "social activity" but there was the pleasure of cooking your own steak on the indoor bbq.

Rumours Bar.... Now that was a scary place, with the local mooses ready to 'pick off' 'tired and emotional' young aviators.

Tenders Bar,..... no mooses, just the local males who will fleece you on the pool tables

Many of the local "ladies" (if I may use the term) were simply looking for a UK male to trap as a ticket out of there ...