AF66 CDG-LAX diverts - uncontained engine failure over Atlantic
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It's a little hard to tell from only 2 picture angles but it almost appears the remainder of the engine nearly fell off after the event. The entire assembly appears torqued around the pylon with the pylon starting to crumple from the force. It all depends on how quickly the remaining rotating assembly stopped but it's easy to imagine that torque being in 10 thousands plus of foot pounds. Then you have to think about the wing structure the pylon is tied to...
On an engine missing ferry, I would wonder if a ballast load is needed to keep the same general flutter margins. The first 74's needed DU weights on the outer engine pair to pass flutter test in certification.
On an engine missing ferry, I would wonder if a ballast load is needed to keep the same general flutter margins. The first 74's needed DU weights on the outer engine pair to pass flutter test in certification.
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Material science tech here.
I would bet you lots of money that this is due to material failure. Most likely manufacturing issue, like the Sioux event.
Pictures tells me the fracture edges are sharp and clean which suggests rapid phase change in the material, to the point of breaking.
The initiating event might have been a smaller fracture in f.ex. a fan blade (or what else floats your boat) and the accompanying force redistribution was enough that the flawed crystal structures said bye bye and left the building with the entire front attached.
I would bet you lots of money that this is due to material failure. Most likely manufacturing issue, like the Sioux event.
Pictures tells me the fracture edges are sharp and clean which suggests rapid phase change in the material, to the point of breaking.
The initiating event might have been a smaller fracture in f.ex. a fan blade (or what else floats your boat) and the accompanying force redistribution was enough that the flawed crystal structures said bye bye and left the building with the entire front attached.
You mean like this? https://www.youtube.com/watch?v=ca4PgyBJAzM
OAP
Thank you for your interesting and courteous correction of my comment about airloads and speeds. Why I sat where I did and you sat where you did LoL. Me being wrong about the loading and the diversion field.
All the same not a scenario many people are ever going to face
Thank you for your interesting and courteous correction of my comment about airloads and speeds. Why I sat where I did and you sat where you did LoL. Me being wrong about the loading and the diversion field.
All the same not a scenario many people are ever going to face
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Isn't this the second incident on the A380 where there was an engine blow out? Qantas flight 32. Can't be due to a specific engine supplier as the former uses GP7000 and the latter uses the Trent 900. Could this be a fault in engine design or just poor maintenance?
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@foxdeux pls read up on what exactly happened
on AF66 the FAN including the fandisk detached from the shaft and departed the aircraft
on QF32 the TURBINE disk FRACTURED
and the engines are very different not just a different supplier. so it can be a fault in engine design but it can't be the same one because a fracturing oil tube (what happened on QF32) would not make the fan depart the aircraft.
btw the QF32 manufacturing fault grounded a significant part of the A380 fleet and was rectified.
did you even read this thread? :/
on AF66 the FAN including the fandisk detached from the shaft and departed the aircraft
on QF32 the TURBINE disk FRACTURED
and the engines are very different not just a different supplier. so it can be a fault in engine design but it can't be the same one because a fracturing oil tube (what happened on QF32) would not make the fan depart the aircraft.
btw the QF32 manufacturing fault grounded a significant part of the A380 fleet and was rectified.
did you even read this thread? :/
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I don't think a fan blade failure would cause this. I also don't think a fan disk failure would cause it either as the fan disk is too far forward of the separation point. More likely is the failure emanated right at the point of separation of the fan module. Located at or very close to that that separation point is a shaft coupling (fan to LPT shaft) and a bearing structure. I think the conical fractured piece in the Ave Herald photo is part of the bearing support or seal system. More likely, there was a bearing problem that caused the shaft to fracture at that point. See the engine cross-section below:
https://www.tumblr.com/search/gp7200
Also, I don't think the remaining portion of the engine was about to fall off. The engine to pylon mounting system and attachment points are well engineered as are the pylon to wing mounting and attachment points. Think about something, during a turbulent air event, the plane could drop 500 feet or more and abruptly bottom out, the full weight of the engine (14,000 lbs + the weight of the nacelle) pulling against the pylon and pylon to wing. Vertical, side and rotational load factors are taken into account during the design processes with significant safety margins applied. Everything survives thanks to the robust designs employed...
https://www.tumblr.com/search/gp7200
Also, I don't think the remaining portion of the engine was about to fall off. The engine to pylon mounting system and attachment points are well engineered as are the pylon to wing mounting and attachment points. Think about something, during a turbulent air event, the plane could drop 500 feet or more and abruptly bottom out, the full weight of the engine (14,000 lbs + the weight of the nacelle) pulling against the pylon and pylon to wing. Vertical, side and rotational load factors are taken into account during the design processes with significant safety margins applied. Everything survives thanks to the robust designs employed...
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@foxdeux pls read up on what exactly happened
on AF66 the FAN including the fandisk detached from the shaft and departed the aircraft
on QF32 the TURBINE disk FRACTURED
and the engines are very different not just a different supplier. so it can be a fault in engine design but it can't be the same one because a fracturing oil tube (what happened on QF32) would not make the fan depart the aircraft.
btw the QF32 manufacturing fault grounded a significant part of the A380 fleet and was rectified.
did you even read this thread? :/
on AF66 the FAN including the fandisk detached from the shaft and departed the aircraft
on QF32 the TURBINE disk FRACTURED
and the engines are very different not just a different supplier. so it can be a fault in engine design but it can't be the same one because a fracturing oil tube (what happened on QF32) would not make the fan depart the aircraft.
btw the QF32 manufacturing fault grounded a significant part of the A380 fleet and was rectified.
did you even read this thread? :/
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https://www.airspacemag.com/military...r-1873980/?all
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I would bet you lots of money that this is due to material failure. Most likely manufacturing issue, like the Sioux event.
Located at or very close to that that separation point is a shaft coupling (fan to LPT shaft) and a bearing structure. I think the conical fractured piece in the Ave Herald photo is part of the bearing support or seal system.
Engine Alliance Service: 24/7 Parts & Support for GP7200
Propulsor Advantage
Modeled after the successful GE90 program, the GP7200 fan module splits from the rest of the engine, allowing you to save money on spare engine costs.
Modeled after the successful GE90 program, the GP7200 fan module splits from the rest of the engine, allowing you to save money on spare engine costs.
Not much money to bet but do see a grounding coming.
......
I had a look at a GP7200 cutaway. Interestingly it seems the first 5 or 6 compressor stages turn with the fan.
The failure seems to be where the fan attaches to its end of the LP shaft.
Let's just be grateful that the fan didn't contact the airframe after departing the engine.
The failure seems to be where the fan attaches to its end of the LP shaft.
Let's just be grateful that the fan didn't contact the airframe after departing the engine.
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Not sure if anyone has already made this point but given AF066's route right up the middle of the UK it's a relief this didn't happen earlier in the flight, with large chunks of metal potentially falling into populated areas
I had a look at a GP7200 cutaway. Interestingly it seems the first 5 or 6 compressor stages turn with the fan.
The only big turbofan engines I'm familiar with that don't have that feature are the three spool Rolls engines.
Though on the other hand, if it had departed over anywhere in the UK, it would almost certainly have been recovered by now.
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I think the conical fractured piece in the Ave Herald photo is part of the bearing support or seal system.
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number0009,
Here you go, thanks to pax2908! You can enlarge it, just click on the art work.
http://www.pw.utc.com/Content/GP7200...taway_high.jpg
Without specific knowledge or a GP7000 IPC to view we are guessing at best.
http://www.pw.utc.com/Content/GP7200...taway_high.jpg