EMIRATES A380 BNE
 

It looks as though EK have a mystery on its hands

https://www.airlive.net/breaking-an-...d2cm1hf4to1_go

I suspect that a blown tyre (or a wheel, even) will rapidly put an end to any mystery.

A blown tyre is hardly a mystery…

Exactly correct apparently!
Kevlar lining mod needed for that area?

While there may not be a mystery as to WHAT happened, what are the possible ramifications of this event? What is the potential for more significant damage to the aircraft and its occupants?

And how should this event have been handled by the crew? Passengers describe a significant sound attached to this event. Was the cockpit crew aware that something had happened? Someone in the cabin crew must have heard the noise as well. One would assume that the cockpit was notified.. The event occurred 30-45 minutes after takeoff, so close to cruising altitude.

If the cockpit could have seen the damage to the aircraft, I assume that they would have returned to DXB at that point in the flight.

Ramifications exist to pretty much any decision one makes, hardly unique to this one, all decisions have consequences, just need to work out which one isn't the worst. The Ramifications are more aligned to ones decision making.

I highly doubt inside the bay Airbus has installed infrastructure that could cause significant airframe issues should a wheel decide to cause problems. I don't believe much more significant damage would have occurred beyond this, however let the engineers answer that one.

Landing at that weight is another problem in itself, especially if one has wheel problems. A380 rough sort of calculations, would be 8 hours holding to get to a weight that I would be comfortable with.

With the lack of info they had available, its either hold for 8 hours, or continue to BNE. First option you will never get in trouble for. I understand holding for such a timeframe is extremely unpopular with the punters down the back, and potential pressure from other pilots next to you against such a long winded hold, but I can't say I've ever seen a training department throw the book at someone for making that call.

You don't subscribe to The Aviation Herald's theory of a missing bolt from the NLG??!?:} :ugh:

Wasn't there another A380 that had similar damage in the last year or two? Or am I thinking of a 777? I am sure I recall another, similar, incident, but the details are a bit hazy.

Thats a wing/body fairing in an unpressurised part of the aircraft. Absent any way convenient way to actually visualise that damage why would the crew return an apparently normal aircraft back to DXB?

PoppaJo, you've been flying the 737 too long. The 380 has fuel dumping capability.

From memory only, I recall the Super cannot jettison fuel to get below MLW. Ie- you will land with 40/50/60T still too heavy, hence the long hold to burn (should one elect to land below in a circumstance). CG Limit is reached with significant fuel on board, cannot offload further unless one wants further issues. I am sure the A380 drivers can elaborate more.

My apologies then Poppa. On other types Airbus gives lots of latitude to land over weight if needed. I can’t imagine that landing 40 tonnes over would be a big deal if needed. In this case how would you reconcile a hypothetical subjective report from the cabin if the aircraft was flying normally, no leaks or vibrations and no cargo fire warnings?

Anyway, I like the magic nosewheel bolt theory. It introduces an element of fantasy to how we previously understood aerodynamics.

The Aviation Herald reported a missing bolt and end cap from the nose gear.
It also reported that the crew suspected a blown tyre on take-off.
It also reported a hole in the wing root fairing,
Aviation Herald made no linkage to any event causing the other.

However, one could link the events logically and speculate that the bolt and/or end cap fell off during the takeoff roll and damaged one of the centre gear tyres which exploded after gear retraction.

As far as A380 Emergency Procedures go, possibly the only indication that the crew had was an ECAM telling them that the tyre pressure was low and WHEEL page showing the actual low pressure or XX if the sensor was damaged.

A380 FCOM says that abnormal action for WHEEL TIRE PRESSURE LO > Crew Awareness


https://cimg1.ibsrv.net/gimg/pprune....1022fdb6cf.png

No, I don't.

That's to say, in the absence of any evidence I don't subscribe to the theory that the two events are necessarily connected (npi).

Aviation Herald is great at reporting facts, but its efforts at analysis are frequently less successful, often concluding that 2 + 2 = 5.

Make of it what you will.


https://cimg1.ibsrv.net/gimg/pprune....8debdfc2aa.jpg

Part of the panel came off? Happens.

The flight crew knew because they mentioned it when they were landing to have emergency services on standby because they blew a tire. They probably didn't know the extent because it would seem more logical to land at their mainbase where it would be easier for repairs to be made to the aircraft, compared to a 'remote' (compared to main base) location

Question from a non-pilot but (ex) aerodynamicist: Wouldn't such a hole affect the aerodynamic characteristics of the aircraft; asymmetrical drag, increased fuel burn, noise, buffeting etc? Clearly not perceptible to the pilots in this case, but I expect that a rigorous examination of the data would show some deviation from "normal" flights?

not that much in that area. There is a fair amount of separated flow near that location. There would be localized vibration and noise increase. If the flow impinged the tailplane then there could be some low-frequency vibration. As often as not the crews get a surprise after landing as to how much damage has occurred. Damage around the nose is more noticeable, or on the wing LE... this plane below lost 3 out of 6 leading edges... flew like a brick.

https://cimg2.ibsrv.net/gimg/pprune....e2303b96a.jpeg

B747's at hot/high heavy airports used to routinely blow body gear tyres at rotate, they would mainly shred the pack fairings, and we would find out by the ATC reports. The old reef runway at Hickalulu also used to have lots of 747 tyre pieces around the runway, and bits of fairings. stopping using retreads at least on the body gear reduced lots of annoyance. At least 744s would tell you that a tyre had failed, the classic left it to the imagination.

When you look at the damage the skin is ripped off and outward along a zipper row of fasteners and bent forward … and remained bent that way for many hours in flight…
suggests a significant overpressure (build up) acting inside to out …

a hole in a fairing would not immediately get me excited… if no lines of any kind would be cut … and the pressure fuselage has no damage …

Common sense suggests that for the pilots the difficult thing would be to find out the presence and level of:
1. first damage … for example a bolt flying,
2. immediate second damage … for example a tire being blown as a consequence, …( but they did not report a flat until now and the photo does not show that)… where the pressure (or frags) rips off a piece of fairing,
3. delayed third damage… for example minor damage by either 1. or 2. which initially does not show up on instruments but can get worse over time … for example lines or skin damage progressing… especially when it hit a weak spot ..

So even with a mild event it would be wise to more closely monitor instruments, let a pilot or dead header do a walk around in the cabin/fuselage, instruct the ccw to report unusual issues, … for such a long flight and over water the risk of 3. increases and the workload for pilots increases,

burning fuel and reducing weight reduces other risks, … for example with gear damage…

next to continue or return/divert an option would be to change your route in flight to pass closer to acceptable airports… when that’s not possible, based on criteria, it might be wise to divert or return…

A late flight engineer always told me helping in cases like this was the main function of an FE … his favourite example being a long tear in a wing/surface, where the pilots wanted to ground and he said no problemo …

So it’s up to the pilots these days to find the proper compromise.

And an interesting case for pilotless flying design studies.
For example (one of many questions based on this incident alone) … does a future “aircraft system (which today still includes aircraft plus pilots plus ccw plus (some knowledgable) passengers)” have to recognise that “something” happened, instead of recognising that a “specific thing” happened…and how does that compare with a piloted aircraft (also see the remark above about pilots being surprised about the degree of damage after landing).

What is a A380 "Super" ?

No fuel dump on A380 ?

Don't believe.

The prefix “Super “ is added to the ATC callsign to alert them to the wake turbulence etc for separation. ie as in “Heavy” for smaller Widebodies.
The A380 defiantly has fuel dump, at least the BA hulls do. A relative has used it!.

The A380 is classed as a Wake Turbulence Category J by ICAO, with the recommendation that on initial contact with ATC the callsign be suffixed with "Super" (cf "Heavy").

I don't think the OP actually said no fuel dump (defiant or otherwise :O), but rather that you can't necessarily dump enough fuel to get below MLW and so may still have to burn some off if that's the aim.

https://cimg9.ibsrv.net/gimg/pprune....65d2995e21.jpg

Is it just me... or is the panel blown outwards?

How would a tyre blowing on Takeoff and subsequent debris cause the panel to deform outwards, given that area is unpressurised?

Or is that where the gear bay is & a weakened tyre exploded after retraction

Or is it just an optical illusion and its not blown outwards at all 😅

As for electing to continue the flight, I can imagine exactly how they reached that conclusion.
Received low tyre pressure warning, probably info from the crew about a bang/loud noise.
No other abnormal indications or vibrations etc.
Noise put down to blown tyre, everything operating normally, why not continue...
Tell ATC and ask if any debris found on rwy, tell company and ask if they're happy for you to continue with regards to maint & operational considerations on landing

There is fuel dump on the 380 and you can often be left still overweight following fuel jettison, as you can jettison everything except what is in the feed tanks (which could be a combined 80t or so. Thus, depending on the ZFW, you can easily be over MLW following a dump). Average dump rate about 2.5t per minute. Can land overweight in a non-normal situation though.

DaveReidUK

Thx for clarification.

Yes, you can dump fuel from the A380; except from the Feed Tanks as another poster alluded to!

You can also land at up to 60 tonnes over MLW and as long as the landing is within certain parameters such as touchdown wings level and at less than 320 fpm the overweight landing inspection can be deferred. 60 tonnes over MLW by the way is 455 tonnes for the ULR aircraft in the fleet.

If really necessary you can land at up to MTOW of 575 tonnes; but you won’t be going anywhere until the engineers have given it a good going over!

If you took off with 200 tonnes of good old Jet A1 for DXB to BNE it’ll take about 50 minutes to dump all the fuel not in the Feed Tanks so the 8 hours mentioned by PoppaJo is really a very wild number! I’ll not comment about the 737 procedures; I promise😬

Video showing the a/c and the offending wheel on arrival at BNE:

^^^^^^^Exonerated.

Sorry I was alluding to, if the decision was made to be landing at the minimum weight, ie 60-80T below MLW whatever the number is, due to tyre issues/expected landing roll risks, you need to burn this beyond what the dump is capable of doing, ie your holding for 7-8 hours to burn that away.

However I would expect many to consult engineering whilst in a hold and conduct a overweight landing which as above is still safe, vs holding for such a timeframe. Well, as safe as the docs say, outcomes are always a different story.

To be fair, it's very rare for AVHerald to do analysis. In this article he just reports facts and photos, with no analysis whatsoever. One confusion people often have is due to his habit of reporting quotes without quote marks, so when quotes contradict each other people think it's AVH's fault rather than just different people reporting different things.

There is plenty of amateur "analysis" in the comment section, of course.

About the NLG bolt, the tow after landing was quite long, could it have been damaged then?

On the topic of fuel dump to avoid future confusion based on correct but partial explanation.

Dumping capacity is a necessary evil from engineering and design perspective. As such is preferably not installed unless required by performance considerations, namely
- approach climb gradient for G/A following an immediate turn back at MTOW.

There is no regulatory requirement to reduce down to MLW, a nice Boeing Aero article (T7) explains: overweight is always possible up to MTOW from the LDR / loading point of view. The only concern is the crew needs to find a legal reason to do so. Basically, anything except ops normal is OK.

Neither of the above opposes the prudent decision to reduce and increase margins before attempting to land with a compromised gear.

Interestingly the Wheel nearest the hole is all bright and shiny (compared to the others) as if it had just been replaced/fitted? Or is that just a result of being air-blasted for many hours?

The rear axle of the body landing gear has no brakes. The rims of these wheels are different as well.

https://cimg5.ibsrv.net/gimg/pprune....e13aabbdf2.png
I worked Maintenance for 41 years and never saw a tire damaged like this.

So, the gear retracted, the mlg tyre blew in the bay, causing the hole in the fairing panel? Not such an unusual incident really.

IF it was to have been caused by the 'missing bolt' from the NLG, I'd have expected to see damage to the tread surface rather than the sidewall, and for the tyre to let go prior to retraction, in a similar vein to Concorde. I dunno, maybe there's some interrelation I'm not seeing...

Has anyone confirmed the claim from the AvHerald comments section that the "missing bolt photo" was indeed from 2017 and is unrelated to the tyre blowout?

IF the tire didn't let go on or just after leaving the ground, the next opportunity for its highest stress would be, when the aircraft does reach altitude, when the pressure difference between inside and outside gets to the max, combined with the low temperature to give the lowest plasticity / the highest brittleness of the rubber and carcass.

The picture also seems to show more sidewall damage, though, of course, you can't see from the picture, whether that's collateral damage from the landing or additional damage, originally there, just like the pre-blowout damage.

Could it be, this signals more towards damage caused during storage/mounting of the tire and less towards an operational damaging ?

Fuel dump - what about A340s?
 

One of the reasons this SLF is here is to help overcome the after-effects of experiencing an emergency landing in July 2000 at Lyon St Exupéry by an AF A340 flying Charles de Gaulle-Johannesburg , i.e. about one hour into the flight, so still lots of fuel onboard, due to a smoke alarm in the cargo hold. It was the fastest descent from cruise altitude I've ever experienced! After landing during the long wait to be processed the pilot reported that fuel could not be dumped because we were over an urban area and that the aircraft wouldn't be going anywhere any time soon due to damage to the brakes/undercarriage.

Does his explanation make sense? Did A340s of that vintage have fuel dumping capacity and would the presence of an urban area make any difference to whether fuel was dumped in this scenario, or was it more a case of wanting to be on the ground in a big hurry and being too busy to bother?

A340-300:

https://cimg9.ibsrv.net/gimg/pprune....a87e2b248a.jpg

FDP A340 - Fuel dumping - Wikipedia

KiloB,
"Interestingly the Wheel nearest the hole is all bright and shiny (compared to the others) as if it had just been replaced/fitted? Or is that just a result of being air-blasted for many hours?"

Looking at the all the reflections on the ramp in the photos/video it would suggest it was raining in BNE.

McHale.