A380 looses engine midfight

[HighBypass 2,339]

...so not a Trent then

[Spam3d 54]

Nope not a Trent 

[Matthew Kane 1,343]

If you converted an A380 into a modern bomber I wonder how much bullets and flak it would take? B17's used to take a lot and these modern machines are tough as well. Difference is the compressed cabin of course but uncompressed and shot at and hit with flak I bet they would take quite a lot as well

A test we would never see 

[Paraffin 2,197]

On 9/30/2017 at 0:12 PM, Chock said:

Yes, they are supposed to and usually do, but what they don't withstand is, after having contained the initial damage, the 450 mph airflow acting like a big set of pliers to lever the cowling off after it has been weakened from containing the blast. So it looks like it did its job okay.

From what I've been reading (pprune and elsewhere), it doesn't look like the containment doing its job, as much as the whole fan and forward nacelle departing due to shaft/hub failure. I imagine the whole thing shooting forward of the wing and then dropping? A fortunate result for the airframe and pax, if that's a designed failure mode and not just luck!

[Bobsk8 12,489]

On 9/30/2017 at 3:59 PM, scottb613 said:

Hi Folks,

Ever see the documentary on the 777 - they were using air cannons to launch large turkeys through the spinning fan blades during testing - pretty impressive stuff...

Regards,

Scott

They did the same thing in the early testing of B 52s decades ago. 

 

[Bobsk8 12,489]

4 hours ago, Matthew Kane said:

If you converted an A380 into a modern bomber I wonder how much bullets and flak it would take? B17's used to take a lot and these modern machines are tough as well. Difference is the compressed cabin of course but uncompressed and shot at and hit with flak I bet they would take quite a lot as well

A test we would never see 

The skin on a jetliner is the thickness of a credit card, Don't think it would hold up to any kind of flak. 

[Matthew Kane 1,343]

36 minutes ago, Bobsk8 said:

The skin on a jetliner is the thickness of a credit card, Don't think it would hold up to any kind of flak. 

Seeing the shredded engines on this one was impressive but it was doing what it was designed to do.

 The only modern occurrences I can think of where commercial jetliners limped home would be Aloha Airlines Flight 243 with the skin shredded off the cabin, also the DHL Cargo Flight out of Baghdad that survived a missile attack. Goes to show how tough these things can be when they have to be

[Spam3d 54]

It's interesting to note that the fancase is designed to absorb the energy of a blade release, not multiple releases or in this case the whole bloody thing detaching. It's common of people think that the engine has to contain a turbine or compressor disk failure but the energy levels in these ruptures are just too great to contain, it's very fortunate that the hub and blades went under the engine and not over or toward the fuselage

[Chock 17,769]

9 hours ago, Paraffin said:

From what I've been reading (pprune and elsewhere), it doesn't look like the containment doing its job, as much as the whole fan and forward nacelle departing due to shaft/hub failure. I imagine the whole thing shooting forward of the wing and then dropping? A fortunate result for the airframe and pax, if that's a designed failure mode and not just luck!

Nah, what I was referring to in saying it did its job, is that if the rotating first stage of the engine came apart, that thing could be doing 20,000 rpm, so it would hit the inside of the cowling with a massive instantaneous force, and the armoured inside of the cowling is designed to contain that, which it quite evidently did because if not it would have possibly taken out the adjacent number three engine too. But there is a big difference between that containing a massive instantaneous blow and it withstanding repeated lever forces from the airflow after it has possibly been loosened when stopping the first impact.

This is akin to trying to remove a wooden fence post, if you've ever tried to do that; you could take a running drop kick at a fence post and the chances are all you would do is break your foot and not loosen the fence post at all, but if you instead rocked that fence post backward and forward, you'd eventually loosen it. I suspect that is what will have happened to the cowling, in that it will have done a great job of containing the initial blow to it, but then it will have been subject to repeated rocking movements from the airflow inside it where the engine partds no longer were, which will have eventually broken its fastenings as they were subjected to forces repeatedly which they would never normally experience. It can be difficult to test for such things, and sometimes things only get sorted after an incident has revealed further potential problems, which is known in the industry as 'tombstone technology' for obvious reasons.

A good example of that is the CFM 56 engine's spinner design, which was modified after a 737 equipped with CFM 56 engines flew through a massive tropical rainstorm whilst on the descent, and its engines flamed out. CFM had never envisaged a CFM 56 flying through a rainstorm whilst throttled all the way back, so they'd only tested the engine when at cruise throttle settings with a water hose trained on it, and of course it funbctioned just fine on that test because the engine was running fast enough to overwhelm the water intake, but when they tested one on a stand throttled back as a result of the investigation into that incident, it flamed out. As a result, the CFM 56 had its spinner redsigned to dissipate water more eficiently.

Of course much of the evidence of this engine failure will be at the bottom of the Atlantic, so we may never know exactly what failed, but you never know, those BEA people can be pretty smart even when they haven't got much physical evidence to go off.

[WR269 367]

23 hours ago, Matthew Kane said:

If you converted an A380 into a modern bomber I wonder how much bullets and flak it would take? B17's used to take a lot and these modern machines are tough as well. Difference is the compressed cabin of course but uncompressed and shot at and hit with flak I bet they would take quite a lot as well

A test we would never see 

well if you read the report on QF32 and how much damage the big bird took, you will be impressed. Not to mention it landed with nearly 10 ton of fuel imbalance on the wing tanks, with half its flight system shot up and no anti skid....impressive indeed.