China Eastern gets a nasty looking hole in a wing

[zukini]

China Eastern 777 MU588 yesterday had to return to JFK with a torn looking wing. Story on simply flying.

[India Four Two]

Part of the inboard left spoiler and adjacent skin missing:

https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/798x822/eb0gdjhvuaa1spe_649bf458a2a30e3686bd498f4162c9368448130f.jpg


https://samchui.com/2019/08/13/china-eastern-diverted-to-jfk-after-part-of-spoiler-fell-off/

[Auxtank]

Looks like a spoiler ram has got fed up and jumped ship taking a chunk of skin with it.

[Terry McCassey]

The inboard spoiler PCU sits mid span of the spoiler panel so likely not.

[Terry McCassey]

https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/610x501/hinge_014557ec521aad6bf9b096737867a1b4b26d4e71.png
. . . Or maybe a bit of bother around the inner hinge area.

[Auxtank]

. . . Or maybe a bit of bother around the inner hinge area.

Looks like it doesn't it? So maybe a hinge has gone dirty and some bozo was napping on the C Check ?
Or maybe ripple effect as the PCU put the torque down the wing.
Certainly an interesting failure. Now these birds are getting on a bit.

Oh well, time will tell.

[DaveReidUK]

Five-year-old airframe.

[tdracer]

Does rather look like a hinge seized (for whatever reason - age, lack of lube, defective hinge, etc.) - the force of the actuator was more than the surrounding structure could deal and the structure failed before the hinge.

[Dave Therhino]

The report says they had to turn back shortly after takeoff. Assuming they took off with no damage, at what point would an inboard spoiler have been used in takeoff and climb? Aren't those spoilers ground only (not sure, but I believe that's correct)? If that's correct, my guess is the damage was associated with flap retraction, not spoiler movement.

[pattern_is_full]

Could be.

But could also be a small crack or tear that occured during the previous landing, that didn't become visibly large until the increasing slipstream forces began ripping off parts on the next take-off.

There can be quite a time gap between cause and effect in aviation (cf: Air Moorea 1121).

[goeasy]

The report says they had to turn back shortly after takeoff. Assuming they took off with no damage, at what point would an inboard spoiler have been used in takeoff and climb? Aren't those spoilers ground only (not sure, but I believe that's correct)? If that's correct, my guess is the damage was associated with flap retraction, not spoiler movement.

on most aircraft Some spoilers are also used with aileron for control during turns. Not sure if this applies here.

[Dave Therhino]

That's definitely the case on the 777, I just don't think the very large inboard spoilers are used for roll control. Don't know for certain, though.

[WingNut60]

That's definitely the case on the 777, I just don't think the very large inboard spoilers are used for roll control. Don't know for certain, though.

Gust alleviation?

[Dave Therhino]

Possible I suppose, but the few wing load relief systems I actually know anything about move outboard surfaces to relieve wing bending loads. I don't know any details about the 777 load relief system, though.