Airbus releases AOT for A380 gear inspection

An A380 from London to Dubai on November 9th was approaching Dubai, when the crew received a hydraulic system overheat warning. Because of that warning, the crew used the gravity backup to extend the wing and nose gear. During the procedure, the left wing gear failed to extend, forcing the aircraft to land minus that truck, which is certified to do.

During post flight maintenance, it was found that three wires on both unlock circuits were broken near the iplock actuator. The damage was consistent with wind stresses from repeated cycling. When the AAIS asked other operators, as many as half the airframes checked had damaged wiring.

Airbus has issued an AOT calling for a gravity extension check within 30 days, a wiring inspection, followed by a second extension check within 60 days.

m.aviationweek.com...

a reply to: Zaphod58

Yea, that's the double decker. Not for me, ever.

I would need to see a diagram in order to know but I am assuming that the wires are exposed and during deployment the wind stress has worn them down.

This may be a dumb question but why would there be exposed wiring on such a thing? Is that common?

a reply to: In4ormant

There is wiring in the wheel well itself that is exposed to the wind as the doors are opened. I don't know the A380 specifically, but on the ones I worked on there were a couple places where there were short bits of wiring exposed on the struts. Usually at the end of the run.

a reply to: Zaphod58

Seems an odd design. You would think all of that would have shielding of some kind.

a reply to: In4ormant

There was one for the F-16 antiskid system, on the nose gear, that required a flashlight, mirror, and magnifying glass to check. There aren't many exposed, and IIRC they're up on the wheel well end of the strut where they're sort of protected.

a reply to: Zaphod58

Sounds like you had to check a couple before

a reply to: In4ormant

More than a few. They're a pain in the ass, although the ops check is fun. It's not exactly comfort making being up on jacks at first.

a reply to: Zaphod58

What's the ops check?

a reply to: In4ormant

Operational check. With gear problems it involves putting the aircraft on jacks in a hangar, and repeatedly retracting and extending the gear.

a reply to: Zaphod58
Yeah I have been doing these checks for some weeks now and we have had about 3 aircraft with broken wiring. The problem is crap wiring breaking off the back of pins due to mechanical stress in the back of cannon plugs. The fix is pretty simple, re-terminate the wires on new pins and carry out the drop test again. The test takes about 2 hours because you need to check out both primary systems and both backup modules. And each of the four sides takes over 6 mins to reset because believe it or not its all actually run by clockwork, in the actual sense (so much for the digital age). The other night at 4am it was all going so well, I was co-coordinating downstairs and making sure all the GDO (Ground Door Operation) handles were in the correct position and everybody was resetting the door and gear up-lock hooks as required when on the final test the second LGGCM (Landing Gear Gravity extension Control Module) decided that it wasn't actually working. So the whole test needed to be run again after a box change, "shift change!!" that became someone else's problem. Which goes to show that sometimes one defect can be masked by another. Food for thought if you are in the industry.

LEE.

a reply to: TonyS
Stupid comment. Remind me how many A-380's have crashed as opposed to say 777's?

a reply to: Zaphod58
I'll take the opportunity to point out Zaph that there is more to this than is being said. Lets just say that operators are doing these checks because they weren't being correctly done by many in the first place.

LEE.