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Author Topic: Airbus A380 family  (Read 30368 times)

Offline kitnut617

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Re: Airbus A380 family
« Reply #120 on: December 03, 2017, 11:54:31 am »
Interesting that neither the Engine Alliance or the Roll's was able to contain the fragments within the casing, considering they deliberately grenaded one on a test stand specifically to insure it would.

In the case of the Engine Alliance failure, it should be noted that the 'whole' fan detached itself from the shaft.  I don't think the test you have linked to had that in mind --- 
If I'm not building models, I'm riding my dirtbike

Offline galgot

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Re: Airbus A380 family
« Reply #121 on: December 03, 2017, 12:19:21 pm »
A lot of good engines have been matted to wrong airframe in the history of aviation. From being too heavy, draggy, prone to vibrations, cells have risked ruined the reputation of fairly good engines. Some had to be ran with power slammed forward,  some at the wrong alt and in some case dev Time were inadequate.

I see… So on two incidents, each engine related, it must be the airframe fault… Damn Airbus.
This without knowing any investigations results. Or you know more ?

None of you learned about the P51A, the P36, the hispano engines etc...

Please teach us all… The P51A airframe ruined the Allison V-1710 Engine , or the opposite ? was not born at the time.

Interesting that neither the Engine Alliance or the Roll's was able to contain the fragments within the casing, considering they deliberately grenaded one on a test stand specifically to insure it would.

In the case of the Engine Alliance failure, it should be noted that the 'whole' fan detached itself from the shaft.  I don't think the test you have linked to had that in mind ---

Yes indeed, and it was a different failure on each engine, a turbine blade on the Qantas Trent900, and the whole fan on the GP7200.
« Last Edit: December 03, 2017, 12:35:52 pm by galgot »

Offline draganm

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Re: Airbus A380 family
« Reply #122 on: December 03, 2017, 12:39:20 pm »
In the case of the Engine Alliance failure, it should be noted that the 'whole' fan detached itself from the shaft.  I don't think the test you have linked to had that in mind ---
yes indeed,   it took the ballistic protective enclosure with it. At least this failure missed the wing and luckily the passenger compartment too.

Yes indeed, and it was a different failure on each engine, a turbine blade on the Qantas Trent900,
I don't think it was just a blade, the entire intermediate disc fragmented from heating due to internal oil leak and fire. 3 large fragments some of which went thru the wing, I believe were recovered.

https://nsc.nasa.gov/SFCS/SystemFailureCaseStudy/Details/154

Offline galgot

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Re: Airbus A380 family
« Reply #123 on: December 03, 2017, 12:42:47 pm »

Yes indeed, and it was a different failure on each engine, a turbine blade on the Qantas Trent900,
I don't think it was just a blade, the entire intermediate disc fragmented from heating due to internal oil leak and fire. 3 large fragments some of which went thru the wing, I believe were recovered.

https://nsc.nasa.gov/SFCS/SystemFailureCaseStudy/Details/154

Thks for the info.

Offline DWG

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Re: Airbus A380 family
« Reply #124 on: December 03, 2017, 12:53:50 pm »
What do you think an airframe is?

Irrelevant to the question.

Offline DWG

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Re: Airbus A380 family
« Reply #125 on: December 03, 2017, 01:15:04 pm »
What's the most concerning here is the sudden absence of fact in the replies of some when  it comes about Airbus.

I don't see any reason not to treat this as an attack on my professionalism as an aerospace engineer. With that in mind, I would remind you that a considerable part of my career, both civil and military, was spent working on Boeing projects. Never met a Boeing engineer I didn't like, or a project I wasn't proud to have worked on. Whereas the closest I got to working on an Airbus project was Eurofighter, where DASA/EADS/Cassidian was merely part of a consortium I worked for another member of. If anything I should be arguing in favour of Boeing, but I'm an engineer, facts matter. These are certificated airliners. When you claim we are arguing without factual support, you aren't just accusing us of being corrupt, and I use that word very deliberately, you are accusing EASA and the U.S. FAA of corruptly favouring Airbus and certificating an unsafe design. What exactly was the FAA's motive here?

Your argument about historical engines actually betrays that you are the one arguing from a lack of understanding, not that we are corrupting favouring Airbus.


Offline Archibald

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Re: Airbus A380 family
« Reply #126 on: December 04, 2017, 09:07:14 am »
According to that flawed logic, a perfectly good engine all of sudden explodes because mated to a bad airframe. Which of course can only be an Airbus.
This is really ridiculous.
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Offline Archibald

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Re: Airbus A380 family
« Reply #127 on: December 04, 2017, 09:16:40 am »
What do you think an airframe is?



Randy: Excuse me sir, there's been a little problem in the cockpit…

Ted Striker: The cockpit…what is it?

Randy: It's the little room in the front of the plane where the pilots sit, but that's not important right now.
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Offline TomcatViP

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Re: Airbus A380 family
« Reply #128 on: December 06, 2017, 06:34:55 am »
Modal.


@DWG: I am taken aback. Sorry if I meant to discredit you in anyway. Not my intend. Open discussions involve having opposite opinions on some grounds (and not on some others).

Offline DWG

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Re: Airbus A380 family
« Reply #129 on: December 06, 2017, 08:29:06 pm »
@DWG: I am taken aback. Sorry if I meant to discredit you in anyway. Not my intend. Open discussions involve having opposite opinions on some grounds (and not on some others).

That includes showing respect for the opinions of others, which your comment did not.

Offline Aeroengineer1

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Re: Airbus A380 family
« Reply #130 on: December 06, 2017, 10:25:22 pm »
Interesting conversation.  Overall there is a lack of viewing this as a system. 

First and foremost, while I do work in the engine industry, I have no specific knowledge of this event other than what has been published in the news.  I can say, however, that I design components in the fan section of the engine.  The fan section, and for that matter, the entire engine does have significant interaction with the airframe.  There was some discussion that it was not airframe dependent.  This is not the case.  Now as to if it is a Boeing, Airbus, etc airframe this is not of particular importance.  Each group has slightly different methodologies to achieve very similar goals for airframe/propulsion integration.  Even when a specific aircraft has an engine option from the different manufacturers, the structural pylon for each of those engines is different due to the differences of interaction of the engine with the rest of the structure.

As to the specific failure, it is a very unique failure.  I have my theories on it, but from the looks the entire fandisk separated from the engine and then caused the loss of containment.  With the emergency AD that was issued to inspect the fandisk, one might surmise that there is probable cause in that component itself (potentially a manufacturing defect), and not due to some other factor such as a bird ingestion.  To call this a FBO (fan blade out) event would not be a proper characterization of the event, and the containment case is not designed for an event like this.

Offline TomcatViP

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Re: Airbus A380 family
« Reply #131 on: December 07, 2017, 12:27:25 am »
@DWG: I am taken aback. Sorry if I meant to discredit you in anyway. Not my intend. Open discussions involve having opposite opinions on some grounds (and not on some others).

That includes showing respect for the opinions of others, which your comment did not.

Incorrigible...

Offline Arjen

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Re: Airbus A380 family
« Reply #132 on: December 07, 2017, 03:57:50 am »
What's the most concerning here is the sudden absence of fact in the replies of some when  it comes about Airbus.
I suspect this is what annoyed people. I didn't see it adding anything to the discussion, it being unspecific enough to apply to many who didn't merit such a sneer.

Offline draganm

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Re: Airbus A380 family
« Reply #133 on: December 07, 2017, 10:50:59 am »
First and foremost, while I do work in the engine industry, I have no specific knowledge of this event other than what has been published in the news.  I can say, however, that I design components in the fan section of the engine.  The fan section, and for that matter, the entire engine does have significant interaction with the airframe.  There was some discussion that it was not airframe dependent.  This is not the case.  Now as to if it is a Boeing, Airbus, etc airframe this is not of particular importance.  Each group has slightly different methodologies to achieve very similar goals for airframe/propulsion integration.  Even when a specific aircraft has an engine option from the different manufacturers, the structural pylon for each of those engines is different due to the differences of interaction of the engine with the rest of the structure.
Very interesting indeed. So a problem with the Engine nacelle / wing mounting structure design could affect engine life?  How do they verify there are no unwanted resonances here?  It would imply that even a very small harmonic oscillation  could lead to an undesirable and catastrophic failure no?
  I know that in general these types of things are very difficult to model or predict on any structure. On a massive 380 wing with 2 enormous engines spinning at 3K RPM it has to be quite a challenge.

Offline malipa

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Re: Airbus A380 family
« Reply #134 on: December 08, 2017, 10:01:49 am »
To be honest I don't think you can either blame the engine OR the airframe in this case. This is a system of multiple components, and their interaction will probably have caused this shear off.
It's a bit odd to just start bullying Airbus for this. This interaction is a very hard one to correctly simulate, the field is highly complex. Engineers get a course called Vibrations about these issues and it is one of the more difficult courses.