Qantas grounds A380s after Singapore emergency landing

The Australian airline Qantas has grounded its six-strong fleet of Airbus A380 airliners after one of the superjumbos made an emergency landing. Qantas flight QF32 experienced engine trouble shortly after taking off from Singapore on its way to Sydney. One of the engines exploded with a bang, a passenger told the BBC, and debris was found on an island below.

BBC


The images on the BBC page show where shrapnel from the engine has seemingly passed through the wing, is the engine cowling not supposed to stop this from happening as a part of the aircraft's airworthyness tests? What ever it was that caused the problems seems to have had a pretty destructive effect on the engine.

That is some severe damage to the wing - they are lucky the wing didn't explode because I heard several passengers could see flames coming from the engine. If the debris had punctured the wing tanks, then it would have been all over.

Looks like total disaster was averted.

I'm betting this is a "blade-off" event from the turbine or compressor. It could have severed hydraulic lines in the wings. This has happened before with fatal consequences.

At full power the fan blades spin at a few thousand rpm and are made from hollow titanium. The engine casing is designed to be able to handle a fan blade disintegrating. However the turbine and compressor are spinning at around 10,000 rpm, are usually solid refractory alloys, are extremely hot, and if the turbine disk fails the entire thing flies apart. If part of the compressor or turbine disintegrates, then it there's no stopping it from puncturing anything in its path. Luckily this time it did not happen to slice through anything critical. This sort of accident is fairly rare, but it has happened before, what's interesting with the A380 is it is a relatively new aircraft so in my opinion bad maintenance is unlikely, hence it could possibly be a manufacturing error that effects other aircraft.

Just speculation, so take what I said with a grain of salt.

Also the engines are made by Rolls Royce, a respected engine manufacturer, so no trolling about Airbus, please.

Sounds fishy to me, anything vital above the engines should be reinforced with Carbon fiber shielding. Could have been just a really rare fan blade failure that went through the top of the cowling I suppose. Is there a conspiracy angle or is the MSM targeting some group linked to this? Here is a picture there is an exit hole on the top of the wing and no fan blades appearing through the hole in the cowling?

[atsimg]http://files.abovetopsecret.com/images/member/d4e784d8435a.gif[/atsimg]

Sounds fishy to me, anything vital above the engines should be reinforced with Carbon fiber shielding.

Carbon fiber is not good enough to stop a disintegrating turbine disk (not a fan blade). A reasonably similar incident happened a few years with with a Boeing 767 and General Electric engine during an engine test at LAX. Here are the pictures:


Turbine disk disintegrated:


Turbine disk exited engine, sliced through the entire fuselage:


Turbine disk goes right through the OTHER working engine, gets lodged in the side of it.


There was also another case of a turbine exploding on an MD-80 aircraft on takeoff, it entered the fuselage and killed a passenger.

Here is a picture there is an exit hole on the top of the wing and no fan blades appearing through the hole in the cowling?

It's possible that parts went through the wing and kept on going. I know of no conspiracy angle so far, and I doubt the media would try to blame this on any group...they just need to find out what happened.

Also here's a video:

In the Quantas engine the housing appears to be intact except for the hole in the top, but there must be more damage further forward that caused the cowling failure. The report I read said they could not stop the other engine on the left side of the plane from the cockpit which sounded strange. Fly by wire planes must have independent motor controls that default to a shut down when the loop gets broken? It's easy to see why Quantas is keeping their 380's grounded.

good video their , does anyone know if a bird flying into the engine could couse it to blow becouse i know birds are a big problem at takeoff an landing

Originally posted by Bordon81
In the Quantas engine the housing appears to be intact except for the hole in the top, but there must be more damage further forward that caused the cowling failure. The report I read said they could not stop the other engine on the left side of the plane from the cockpit which sounded strange. Fly by wire planes must have independent motor controls that default to a shut down when the loop gets broken? It's easy to see why Quantas is keeping their 380's grounded.

Here's a better picture:



From discussions elsewhere it is obvious that the Intermediate Pressure Turbine (IPT) disintegrated because:
1. you can pretty much see it in the above picture.
2. There's also another picture of the turbine on the ground, but I don't have the link.
3. engine is designed to contain most failures except those involving the turbine
4. There's nothing that I know of that could cause this except a turbine failure

And this was probably caused by an issue within the engine such as manufacturing fault, bad maintenance, or whatever.

Also it's Qantas not Quantas. Qantas is an acronym.

good video their , does anyone know if a bird flying into the engine could couse it to blow becouse i know birds are a big problem at takeoff an landing

They can be a problem, but I highly doubt birds would cause the turbine to fail. Turbine is at the back of the engine, the bird would damage the fan or compressor before it causes the turbine to fail. With that said, in some of the debris there is what looks like blood, (or it might just be hydraulic fluid, it's hard to tell).



The good thing though, is that everybody in the aircraft was OK, and everyone on the ground was OK, all the debris on the ground were collected, the crew acted professionally, and the aircraft (well... except the engine) performed well. From this incident we will be able to determine the cause of this failure, which will help us take measures so a similar accident does not happen in the future. Qantas has decided to check each engine for flaws, a process that takes 8 hours each aircraft, then if no problems are found they will likely be flying again.

reply to post by C0bzz

Excellent series of posts there C0bzz, an IPT failure seems at this stage the most likely and the TRENT 900 has had ongoing issues with the IPT and HPT that RR have been working through, but honestly I thought they were on top of it. This may be an unrelated issue though. I have worked on this particular aircraft recently and a work colleague recently accompanied it for it's first C check in Germany so I will talk with him

I dont know about the blood like fluid you mentioned I havent seen any pics fitting that discription but then I was out of commission for 24hrs with a tummy bug so cant be sure. It may be Skydrol hydraulic fluid it is purple when fresh and often goes an amberish colour when old. Only other thing that is sometimes used as a corrosion inhibitor and might look like stale or dried blood is Ardrox.

I will be at work tomorrow as it is the airlines 90th birthday celebrations so you can guess what the number one question will be from all the people attending the open day, "wha happen?". If I hear anything on the grapevine I will try and let you all know, see if I cant get the full story.

Most likely it's totally unrelated, but Qantas have just suffered a second engine scare on one of their aircraft, this time a jumbo.


BBC

Looking at the photo, you can see the blackened soot marks. The engine has suffered a surge and flame out. This is where the pressure at the rear of the engine builds up and exceeds the pressure at the front. This causes a reversal of airflow and therefore the engine stalls. Sometimes a flame can be seen at the intake aera or the bypass area, as in this case. These surges can cause a catastophic failure, as in this case, of the engine, sometimes causing it to explode. What casued the surge? Good question. In this case, I would guess it was due to turbine blade migration. However, it can be caused by Foreign Object Damage (FOD) as in a bird strike or other material injested. Poor fuel management or engine management system software could also cause it, but less likely.

Airbus A380 tanks are self sealing. My take is, although this is a serious incident, the aircraft was never in danger of being lost.

It was a failure of the IP turbine as point out already.


What hasn't been pointed out is that there is already an AD served on the Trent 900 with regards the IP turbine shaft splines wearing unduly quickly.

This wear can result in the turbine disc moving backward, running the bearings dry, with the inevitable disc failure.



edit: Its a very nervous time for R-R. They might have to make substantial mods to every Trent 900 (and possibly the Trent 1000 in the 787) already made or in production.

Could there be any link to the volcanic activity in that part of the world?

Iceland hit the EU hard with ash high in the air - surely the large deposits being made from Indonesia currently would get into the air-stream and possibly flight-paths?

reply to post by kilcoo316

Interesting. I will have a look for this AD when I get to working on Monday. Do you happen to have the AD Ref?

From pprune:

AD 2010-16-07. RB211-Trent 970-84, 970B-84, 972-84, 972B-84, 977-84, 977B-84, and 980-84 turbofan engines. These engines are installed on, but not limited to, Airbus A380 series airplanes. "Wear of shaft rigid coupling on several engines during strip." Earlier history; Refer to MCAI EASA Airworthiness Directive 2010-0008, dated January 15, 2010, for related information.
AD source and Link > Rolls-Royce plc (RR) RB211-Trent 900 Series Turbofan



AD 2010-17-13. RB211-Trent 970-84, 970B-84, 972-84, 972B-84, 977-84, 977B-84, and 980-84 turbofan engines. These engines are installed on, but not limited to, Airbus A380 series airplanes. "To detect cracks in the low-pressure turbine (LPT) casings, which could result in the release of uncontained high- energy debris in the event of a stage 1 blade failure."
AD source and Link >
Rolls-Royce plc (RR) RB211-Trent 900 Series Turbofan


Another AD for 900s series but no mention of uncontained explosion.
2009-18-13; Title: Rolls-Royce plc. (RR) RB211 Trent 900 Series Turbofan Engines
"We are issuing this AD to prevent the release of a high-pressure (HP) turbine blade, which could result in an engine power loss or in- flight shut down of one or more engines, resulting in an inability to continue safe flight. Evidence from development testing and flight test Trent 900 engines has identified cracking on some HP Turbine Nozzle Guide Vane (NGV) Convex Surfaces."
AD source and Link >
Rolls -Royce plc. (RR) RB211 Trent 900 Series Turbofan


www.pprune.org...

reply to post by C0bzz


Thank you for the info. These failure modes could certainly cause a pop surge and flame out. It would be interesting to know if Qantas had actually carried out this remedial work

Originally posted by AlwaysQuestion
Could there be any link to the volcanic activity in that part of the world?

Iceland hit the EU hard with ash high in the air - surely the large deposits being made from Indonesia currently would get into the air-stream and possibly flight-paths?

Coincidence or not, this is a particularly active time for volcanoes in the area, Indonesia specifically., not too fare away.

www.bbc.co.uk...

But based on reports it does not seem related..so far..

reply to post by Daedalus3


That is a good link although the cell phone video earlier in this thread seemed to document things fairly clearly. By the time the passenger got their camera aimed out the window the hole was already in the wing and the remainder of the aluminum skin could be seen peeled up in a loose flap. The pilot was apparently still climbing out and was near 10,000 feet when the turbine let go. When they dipped the wing turning back you could see the islands below. Any play in the turbine bearings would be noticed the most under load during climb out.

The Australian airline, Qantas, has said it has found "slight anomalies" on three Airbus A380 engines and is keeping its fleet of six passenger jets grounded for further checks. Chief executive Alan Joyce said there "was oil where oil shouldn't be on the engines" of two of the super-jumbos.

BBC


Seems like there is more bad news for Rolls Royce, not sure how long it would take to rectify these problems? and will they be made to cough up compensation to those airlines affected?