http://www.chicagotribune.com/business/breaking/chi-wing-cracks-found-on-a380s-safety-unaffected-20120105,0,5457262.story What causes this problem? Is it simple material fatigue from the bending in the wing? I would have assumed that they ran plenty of simulations and calculations to where the wings could handle countless cycles without this becoming a problem.
The article said that they don't consider it a safety issue...but this plane hasn't been flying that long. I was on a Super 80 last month that was only a year younger than I am, the A380 is just an infant.
I'm sure they don't consider it a "safety issue". After all, what's the worst that could happen? Structural failure? LoL! But, what do we expect Airbus to say? If there's a problem with composite construction, and they've bet the farm on it, it's not like they can change at the drop of a hat, either. If it's a legitimate concern, and these planes need to be grounded, that would be catastrophic for Airbus AND the carriers. CW
Wow. Amazing. Just goes to show that all the simulations in the world can't always predict real world behavior. I'm curious if it's in the same location on all affected aircraft. With CF, the laying of the fibers is very important. If in different locations it could just be an oops with manufacturing. If it's in the same general location, then one or more of the transferred loads isn't playing nice with some of the components. No bueno, all the way around.
I'm not sure where these cracks are but if they are in the primary wing structure (spar box) they have a serious concern and safety problem. If they are in the secondary structures (trailing edge,etc.) that's not so serious but attention getting. Cracks in the wing skins can be from a complex series of causes i.e.; alloy used in the skins, abrupt runout in the pad-up areas, lack of and/or improper load dispersal. It can go on and on in the wing of a big bird like that and it takes the very best engineering skills and years of experience in designing big wings...like Boeing.
I doubt if it's a big deal if you monitor it, and eventually they will come up with a fix involving sticking a doubler on there or something like that, and beefing up the new aircraft in production. This isn't uncommon with new aircraft designs. That's why you don't want to fly the "A" model of anything!
If the engines continue to blow up, this will be the least of their worries. They were milliseconds away from losing ~500 souls last time that happened. It's only sheer luck that that the red hot debris from the disintegrated engine was flung in a direction that did not lead to the wing skin and fuel tanks being ruptured. Seems like there are too many flaws for it to be put in service. This plane is going to kill a lot of people if things go catastrophically wrong.
The engine disintegration DID puncture the fuel cell on the A380. If I remember the mist flowing back from the wing was fuel that failed to ignite. Jump me if I'm wrong.
So far as I know, it didn't puncture the fuel tanks. Thank god. I will double check...have a childhood friend in a very key position (with respect to this program) at RR.
Some interesting info here: http://blogs.crikey.com.au/planetalking/2010/11/17/the-anatomy-of-the-airbus-a380-qf32-near-disaster/ The wing was punctured, but the projectile(s) traveled through control structures and hydraulic lines, not the fuel tanks (amen). The fire must have been hydraulic fuel catching fire, or fuel being injected into the nacelle. My heart starts quivering when I think about this incident. The projectiles were hurled from the disintegrating engine due to centrifugal force. Their trajectory could have been at any angle, and it was simply a miracle that the path they followed did not bring them into contact with jet fuel.
Ah, ok, the tanks were punctured. So, were the tanks empty? Or did the fuel not ignite for some other reason?
The mist of fuel and hydraulics failed to ignite I suppose that it was too far aft of the hot stuff in the engine. Unbelievable.
Zack- Jet A is primarily kerosene. You can pour Jet-A on the ground and drop a match on it and it will not ignite. At altitude, there is way less oxygen than near my theoretical puddle. Most leaks are just that, leaks. Not the same as a recip airplane leaking 110/130 aviation gas. Takes a pretty good ignition source to ignite Jet-A.
Thanks yes. From my conversation with my buddy at RR, it seemed that the shrapnel that went through was very hot, so it was indeed a miracle that it did not ignite. I guess the pieces cooled off enough in the short time they were subjected to the sub-zero temperatures?
I didn't think about all that, Taz. I was thinking of a 707-320 leaving SFO that sustained a turbine burst in number 4 shortly after take off and ignited fuel in the outboard wing. Number four strut is located right at the tank end rib between the inboard and outboard wing so the fire was isolated in the outboard wing. The engine and strut finally dropped off the wing, thanks to the shear pins but the wing continued to burn until it began to twist, becoming a big aileron. The pilot rolled the airplane back and forth until he finally broke the flaming wing off. He trimmed the left aileron and the rest of the airplane and called for flaps 20 and made a safe landing. I imagine that the pieces of the J-75 were hot enough to ignite the fuel and the 707 wasn't at a very cold altitude. I still think that A-380 missed a bullet but you made a very good point that provides the answer why there was no ignition.
Like I said in another thread, it's the fumes (accumulation of) and /or very fine atomization that burns, not the liquid. Dodging bullets indeed. I've stubbed out cigarettes in in a can of gasoline before, no big deal, but I didn't make a habit of it.
I seem to remember that the engine, or parts of it, wound up falling into a suburban house's kitchen, fortunately without personal injury. I recall some jokes going around about the day's special menu feature - turbine stew!
Was this the pilot who had previously seen the maneuver on a fighter aircraft? He didn't know if it would work, but tried it...? I seem to remember reading about that, but don't know if it was this incident.
