You don't think EA have a vested interest in finding out what happened to their engine?

I wouldn't be surprised if they are already chucking large sums of money at a search effort while the AIBs argue about whose jurisdiction it is.

Or do you think they will be twiddling their thumbs in East Hartford and Cincinnati while the regulators debate grounding all their customers' aircraft?

Only takes a look at that cutaway against the pictures of the failure to think that bearing failure is highly unlikely. The remains of the fan disc on the engine suggest that to me. Why the rest fell off is more likely to be worked out in the lab and will not take long.

I'm confused. What are you seeing in the photos that you believe to be part of the fan disc?

The consensus seems to be that the fan departed in its entirety.

LP Turbine
 

Comparing the pictures of the damaged engine and the one posted by Turbine D, it appears that the LP compressor hub separated quite nicely.

Just seen this

Failed Fan Disk
 

A small remnant portion of the fan disk appears to still be attached to the the low turbine shaft hub.

Possibly the hub portion of the disk that attaches to the stub shaft just ahead of the bearing.

There should be a fracture progression there telling which direction it has progressed. Also there is the booster stage drive flange that also would show which directions the separation was taking vs a clean break away.

Meanwhile I'm sure that the pedigree of the Titanium process is being examined in detail at this time to see if there is anything at all that is of concern that might point at other parts of the fleet..

To me it is amazing that the blades themselves did not add to the collateral damage to the aircraft (like Pensacola MD80) and the best news yet. No doubt the Kevlar ballistic protection might have played a significant part.

Alber Ratman,
There are no fan disc remains left on the engine or in any photos of the engine. The fan disc departed with the fan blades and outer casing portion that was covered by a Kevlar wrap. If you look at the artist cutaway depiction, everything forward of smaller (blue) LPT shaft is gone except for a fragment of the larger diameter short fan shaft (also blue) that remained. And I think that is what you see in the Aviation Herald photo.

Why would there be arguing? The rules are quite clear:

Denmark has the lead (state of occurrence)
Rights of participation:
USA (design and manufacture engine)
France (design and manufacture airframe, operator and registry.

Everyone else provides assistance as requested. It seems obvious that Canada plays a major part as that's where the aircraft is.

Given the scale of the investigation and that, other than being under the flight path they have nothing to do with it, Denmark may choose to hand it over to one of the others. But that's their choice to make.

If not Denmark, who takes the lead?
It would seem that the engine manufacturer has the most to learn/lose, therefore the aircraft manufacturer (or would it be the owner?).

Who stands to benefit most?

France would seem to hold two of the claims (manufacturer/operator).

That leaves Canada as the current location of the 'wreck'.

DOH!

Thanks :)

The public, who depend on an impartial investigation by expertise appropriate to the challenge.

I'm confused on this thread about what nation administers the the location (Danes or Canada) nut I'm sure that the governments know and have already sorrted out what investigative agency should take the lead, considering available resources and interests. No sense in the rest of us guessing

They will be arguing (well OK, negotiating) because the Havarikommissionen is unlikely to have the resources (nor probably the desire) to launch and lead what is clearly going to be a complex investigation with far-reaching implications. That means they will have to choose who to delegate the investigation to - almost certainly either the French BEA or the Canadian TSB.

Nice pic of the engine from directly front-on in that twitter link (this page) ;

http://www.pprune.org/members/441157...gine-front.png

Unfortunately I had to screenshot it and upload it to an album and it got shrunk :(

Links to the full size twitter pics (not mine):
https://pbs.twimg.com/media/DLGV5R-V4AEAH0P.jpg:large
https://pbs.twimg.com/media/DLGV5R5VAAAgsx6.jpg:large

It looks like the whole fan module fell off. How is it attached? What would happen first, failure of the bolts on the outer flange or fracture of the shaft?

Zoomed highlights attached.

Thank you, it certainly helps to better understand the photos we've seen.

Think you nailed where it broke. Looks like the short fan shaft sheared where it tapers near the front of the LPC.

https://imagr.eu/up/WjDiL_DLGV5R5VAAAgsx6.jpg
......

"The flight data recorder and cabin voice recorder will be arriving in Ottawa on Tuesday for analysis, he added."

They also have the aircraft, therefore they will lead the investigation after Denmark demurs.

Also French speakers in Canada.
.

I can't believe that fractured part is the only attachment to the shaft. Surely there's a supportive ring/hub that's missing that's normally further forward?

If not, and it certainly looks as though what you see is what you've got, it's perhaps the most bewilderingly optimised critical part I've ever seen.

look at the 11 O'clock left corner in the pic (under increased brightness).

I wonder if they can get that stub shaft attaching piece off while on-wing (saves time on the front end of the investigation)

As a Canadian taxpayer, I would hope that we don't get stuck with the bill!

I know that the investigation of SR111 contributed to the advancement and knowledge off aircraft design and manufacture, but it was a huge cost to us in Canada who pay the bills. With the world's 2nd largest land mass, but only 10% of the population density per square Km of the US, I believe it behooves the countries that built, sold and certificated the engine and airframe to assume liability for the investigation!

Where the heck are all the fasteners on that flange?

Did this engine have a fan change recently?

Stumpy, I been wondering the same thing - was there a fan module change or similar maintenance done recently that wasn't done properly...

number0009, infieldg & tricityb,
Thanks for the new photos, they help in understanding where the fracture of the shaft occurred. What can cause this, besides a material defect in the shaft, is the bearing starting to fail. The fan loses its center of rotation and begins to chew into the outer casing about the time the shaft fails and what you see in the photos is the end result. This is speculation on my part, but it is a viable scenario of events.

Loose rivets,
The fractured portion of the part you see is a piece the stub (short) fan shaft as it tapers to meet the LPT shaft, not an attachment to the shaft...

Really? That would be a major screw-up and as such, I highly doubt it would wait a minimum of 5 hours of flight time to manifest.

This is the GP7200 bolted ring that attatches fan - hub - IP Drum, where all the fasteners have disappeared.

OPen the below image and you can clearly see the fan hub retention nuts and Allen bolts through to IP Drum.

I would hazard that on AF66 the Allen bolts are still there but I can clearly see several sheared fan hub bolts.

Hydrogen Embrittlement, maybe?

Hmm looks like it split into two equal halves from the dents on the inboard booster fairing

Or a wobble.

Long shot, does the fin camera on an A380 record live images?


If so I'd pay to see that.

CVR. Is it available?
 

Thinking of QF32. They could not shut down one engine so the CVR kept running. The CVR of the incident was overwritten because CVR only records 30 minutes.

As I recall, AF66 kept pax on aircraft for quite some time after landing. Does the CVR keep running when only the APU is running? If so, what is the likelihood of the CVR not being of any use to the investigation? i.e. overwritten while on ground.

I suspect the crew was on the ball and pulled the breaker or the 380 logic is similar to the other Airbus's and stops recording once engines/beacon are off.

Considering how much TV a hard drive can hold, nowadays it would be very easy to have forward and rearward looking cameras with hours of storage time.

Two cameras on the tail plane tips looking forward would capture a lot of possible inflight events.

The incident occurred 2 hours before the plane was on the ground; the lead-up to it (a good 20 minutes of shifting headings) could only be on the CVR if it had been turned off in the air. If the crew wanted a potential evacuation procedure to be recorded on the CVR and only turned it off after the plane was confirmed safe, the event itself won't be on it. The FDR is going to be much more useful, I bet.

RE the comments about stopping the CVR in flight ..I don't think an SOP of pulling the CVR recorder in flight is a good thing at all. With the benefit of hindsight doing so might have been in the current AF investigation but what about a hypothetical incident which unlike this one doesn't end well, and unfortunately ends up with a crumpled heap of metal under the approach or off the overrun.

Let's say an engine goes pop as it did in this case, the issue is contained OK initially and a decision is made to pull the CVR.....since the CVR was stopped we now have a well preserved record from the cruise of a thump, somebody calling for a severe damage separation checklist, a bit of T-DODAR....and then nothing....no record of any subsequent analysis done by the crew, any reassessments during the descent, any descent/approach briefing, any conversation/comments made during the approach.

There certainly seems to value in increasing the CVR recording time, and in any event a lot will be gleaned from the flight data recorder....but pulling recorder CBs in flight?

From the Twitter image linked by tricityb in post #175, it appears that 8 bolt holes are obstructed (bolts sheared off?) while 16 holes appear empty. The largest sector of empty bolt holes spans 120 degrees.

It's bolts first for me, if it had been hub then the fan would have lost its drive and slowed down.


So it's a fan - IP drum bolt failure leading to an unloading and extreme imblance of the LP/IP system causing overspeed and subsequent fan hub failure before the LP Turb entangles.


We shall see...........disastrous for GP powered A380s, less so if it's a maintenance error (wrong bolts, insuficient torque, wrong anti-seize, rogue parts etc).

I took the liberty to point out the position of the LP compressor mounting flange in Orestes pictures.

That nice illustration gives the impression that the flange is eccentric?

am i correct in assuming the red line is where the boltface visible in the pictures is located?

But that's not the compressor hub flange .. the comp hub flange is behind the sheared off cone section ... check the cutaway. If you look at the image, further back down the shaft, deeper in than the curvic coupling, you can clearly see the compresser hub flange.

The section you have indicated does not rotate ...

If it doesn't it should from now on