Posted on 02/16/2006 2:01:08 PM PST by A.A. Cunningham
Airbus A380 test wing breaks just below ultimate load target
The wing of the Airbus A380 static test specimen suffered a structural failure below the ultimate load target during trials in Toulouse earlier this week, but Airbus is confident that it will not need to modify production aircraft.
The airframer has been running load trials on a full scale A380 static test specimen in Toulouse since late 2004 (pictured below). After completing “limit load” tests (ie the maximum loads likely to experienced by the aircraft during normal service), progressively greater loads have been applied to the specimen towards the required 1.5 times the limit load. Engineers develop finite element models (FEM) to calculate the load requirements.
“The failure occurred last Tuesday between 1.45 and 1.5 times the limit load at a point between the inboard and outboard engines,” says Airbus executive vice president engineering Alain Garcia. “This is within 3% of the 1.5 target, which shows the accuracy of the FEM.” He adds that the ultimate load trial is an “extremely severe test during which a wing deflection of 7.4m (24.3ft) was recorded”.
The European Aviation Safety Agency (EASA) says that the maximum loading conditions are defined in the A380 certification basis. “The aircraft structure is analysed and tested to demonstrate that the structure can withstand the maximum loads, including a factor of safety of 1.5. This process is ongoing and will be completed before type certification.”
However Garcia says that the failure of the wing below the 1.5 target will require “essentially no modifications” to production aircraft: “This static test airframe has the first set of wings built, and we have refined the structural design for subsequent aircraft due to increased weights etc. We will use this calibration of the FEM to prove the adequacy of the structure on production aircraft.”
EASA says that it is aware of the structural failure but "cannot make a statement about the specific failure as it has not been officially briefed by Airbus on what the cause was, and the certification process is ongoing".
Garcia says that the FEM calculations had already established that the A380’s wing had “no margin at ultimate load. We had a weight saving programme and ‘played the game’ to achieve ultimate load.” However in earlier briefings, Airbus structural engineers had stated that it planned to carry out “a residual strength and margin research test” in 2006 after completing ultimate load trials.
The results gleaned from the static testing will be extrapolated for the future aircraft developments over the next 40 to 50 years says Garcia. “It is normal to refine and strengthen the structure of new heavier or longer range variants,” he says.
MAX KINGSLEY-JONES / LONDON
It's not that I'm anti-social,it's just that I don't think I want to be on an aircraft of the size of The A-380!
Think of it as another"successful"Government Program!!!
So did the guys who flew the B-17(as opposed to the B-24)!!!!!!!
Try google, you'll see.
Airbus or Airbust
but not a frozen one ?!
certainly not because it's meant to break the wings. Would you buy a crash tested car ?
deodorant might be supplied from the air con....
Yes that would cause one to have a brown alert.
I would buy a car that went through crash tests to see how well it would hold up in an accident ... isn't that the same for airplanes? Test the wing to make sure it would exceed it's design limitations?
sorry I got you wrong - I thought you where demanding they tested every production aircraft...
As I understood they will be fine with the wingtest. Rules allow, that they take the findings of the testflights to asses the 100% Limit from real data instead from all computerized models that usually feature a saftey margin by themselfes.
They will just show up with the enhanced construction they allready use for production aircraft and the new calculation of the 100% load for the wing. I wouldn't be afraid in an airplane like this - it's much safer then a smaller one since gusts and vortices in the air will have a hard time to influence its steering while landing - size matters.
50% safety margin for a bird like that sure is a lot more extra load then for a 737 or A320.
The last exciting question for the 380 project will be -
Can 800 people get out of this plane in 90 seconds ?
That may not be computer modelled and I don't envy the test persons. It is said that bruises and black eyes are part of the reward you get in these tests.
Ok I understand ... I just got into aviation - private now going for instrument and I subscribe to the the NTSB Reporter ... hope to go to Embry-Riddle for ATP jet - working like crazy saving up ....dad said he'd help ...
Yes. Maybe they should be load testing the vertical stabilizer instead?
Presumably!This thing is so big,that each level(deck)would be embarked(and dis-embarked)separately!!Too BIG!!!!!!!!!!
But if I got it correctly bulk transport is, what we will get anyhow.
If we want to enjoy growth and prosperity in the future we will have to shoot more people around the globe.
At the same time we will see fuel prices on their way up and airport capacities on the maximum they can take.
Independantly of that there is a demand for more flexible transportation (787 beeing the answer to that)for the comparably homogeneous spread economic centers in the US and Europe.
But if india and china with their mega cities really start to fly you better prepare to be on cattle trains going there and back.
So safe for first class and you will get a stylish armchair smelling of whatever you like ... or register to the bowels of titanic (be it in a 747 stretched strech version or 380XL or in one of those forthcomming flying wings or even on a zeppelin again)
ummm no they dont
ummm no they dont
better to say it twice ;-)
sorry, too much coffee this morning.
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