Air France A380 woes

ednwireland

rustynutz wrote: »

I often wonder about the test they do on an engine in a lab to see if it is contained within the engine housing during turbine failure (I saw it on a documentary about the making of the A380, they had to sacrifice a multimillion euro engine for the test). Surely when an engine fails with a 600mph wind passing over and through it it is going to fail differently than one failing in a lab, with no relative wind

the housing basically has to contain a fan blade its always a biggie in the certification process. Trent 900 below

https://www.youtube.com/watch?v=KHU7PBIezB0

the casing isn't supposed to disappear though damage is supposed to be contained

If you get a disc failure all bets are off that one huge lump of metal to be flying around.

Souix city the disc went through the plane and cut the hydraulics. The pilot nearly landed it just balancing the throttles, gust caught it if I remember right.

Not good for ge and pratt

Captain_Crash

cml387 wrote: »

The Sioux city crash was in the engine, first stage compressor fan. This is an outer main fan failure I'd guess.

I don't think it was a fan failure, the cowling is designed to contain several blades sheering off like that. Look at the QF failure, the engine stayed intact apart from one small piece breaking trough, granted, that one small piece nearly crashing the aircraft but the point is, the engine contained most of the damage (and kept running). The N1 fan actually spins slower and has less energy than the compressors deeper inside, so its reasonable to assume a blade separating, while still a catastrophic failure, is no problem for the aircraft.

There is one close up of the drive shaft and it looks like that failed, resulting is the whole N1 fan disc separating. I'm not a metallurgist, but the visual difference between a piece of metal being torn away, and just sheering off is very distinct, think of over torquing a bolt and what the break looks like after.

Lucky it wasn't no3 engine or we could have had LY1862 all over again, just this time not a cargo aircraft.

murphaph

Would the fan disc move forward relative to the aircraft if it sheered off while spinning at its usual speed? Assuming a clean sheer....which is probably very unlikely.

cml387

Captain_Crash wrote: »

I don't think it was a fan failure, the cowling is designed to contain several blades sheering off like that. Look at the QF failure, the engine stayed intact apart from one small piece breaking trough, granted, that one small piece nearly crashing the aircraft but the point is, the engine contained most of the damage (and kept running). The N1 fan actually spins slower and has less energy than the compressors deeper inside, so its reasonable to assume a blade separating, while still a catastrophic failure, is no problem for the aircraft.

There is one close up of the drive shaft and it looks like that failed, resulting is the whole N1 fan disc separating. I'm not a metallurgist, but the visual difference between a piece of metal being torn away, and just sheering off is very distinct, think of over torquing a bolt and what the break looks like after.

Lucky it wasn't no3 engine or we could have had LY1862 all over again, just this time not a cargo aircraft.

One thing to bear in mind with those big engines is the huge force exerted when the aircraft rotates on take off as the plane changes in pitch, as the rotating fan creates it's own gyroscopic effect.

Could it be that this is causing fatigue cracks on the shaft. You are correct, it looks like the whole fan flew off.

mickdw

Just something I was wondering, with these very large engines, is it getting proportionally harder to design them to contain an engine breakup?
That's 2 major engine issues that I'm aware of on the A380, one from each manufacturer I think and both of them have been questionable in terms of being contained.

Comhrá

Interesting development:

http://www.airlive.net/breaking-missing-parts-of-air-france-a380-engine-have-been-spotted-by-a-danish-helicopter-in-greenland/

ED E

From an investigators perspective they got very lucky that it happened over Greenland, most routes only skim the southernmost tip.

Comhrá

http://www.airlive.net/breaking-missing-parts-of-air-france-a380-engine-have-been-spotted-by-a-danish-helicopter-in-greenland/

"Missing parts of Air France A380 (reg. F-HPJE) engine have been spotted on the ice sheet by helicopter.

According to the BEA, they were located on a desert area covered with ice, located about 150 km southeast of the town of Paamiut, located on the west coast of Greenland.

The missing parts were located by using data from one of the aircraft’s two black boxes, the Flight Data Recorder (FDR), which “determined the location where the damage occurred to engine #4.

The crew of the helicopter of the Danish airline Air Greenland sent on the site was able to recover some parts of the engine. These parts have been sent to the Danish Accident Investigation Office and are being forwarded to the BEA in Paris.

A next mission to recover other parts and to try to locate missing pieces will be organized as soon as the weather conditions allow. Snow that gradually covers debris may make detection and recovery more difficult.

The Engine Alliance GP7000 is a turbofan jet engine manufactured by Engine Alliance. It is one of the powerplant options available for the Airbus A380, along with the Rolls-Royce Trent 900."

jonnybegood

https://twitter.com/DaveWallsworth/status/917887041278566400
Seems they are flying it back on three engines

circular flexing

According the avherald.com, the engine is being removed from the plane and shipped back to GE, they are still figuring out how to get the place back into service.

On Oct 11th 2017 the BEA announced that engine #4 is to be deposited in Goose bay before decisions about the further investigation are to be taken. Teams of Air France and Airbus are going to remove the engine from the aircraft and put into storage. The engine is subsequently expected to be shipped to Cardiff,WL (UK) into a General Electrics facility where the BEA investigators are going to travel to to continue analysis. It is being studied as to how the aircraft can be ferried to Europe for repairs and return into service with Air France. Due to the complex logistics of these operations the schedule may spread over several weeks. In the meantime the search and recovery of the parts that detached in flight over Greenland continues in Greenland.

Must be painful for AF having an A380 out of service for so long.

circular flexing

Apparently the plane is still in Goose Bay. Can anyone confirm/deny this?

marno21

circular flexing wrote: »

Apparently the plane is still in Goose Bay. Can anyone confirm/deny this?

F-HPJE is still in YYR / Goose Bay

drdeadlift

Victorville is the next stop for this bird(wouldnt suprise me)

Dardania

drdeadlift wrote: »

Victorville is the next stop for this bird(wouldnt suprise me)

Qantas brought theirs back (although I think that was considered "pride" or refusing to taint their reputation)

knucklehead6

drdeadlift wrote: »

Victorville is the next stop for this bird(wouldnt suprise me)

Why? Surely there's a lot more life in the airframe

Cookiemunster

Replacement engine to be brought in on an AN124 on Nov 24th, with the damaged engine returned to Cardiff on Nov 25th.

https://twitter.com/flightradar24/status/930860404523356165

knucklehead6

en route

https://twitter.com/flightradar24/status/934003930949914624

knucklehead6

Back at base.

https://blog.flightradar24.com/blog/air-france-flight-af66-suffers-engine-failure-over-greenland/