Have a look at an earlier thread on this:
http://www.pprune.org/tech-log/49982...ing-wings.html
The web's abuzz with interesting morsels about this, here's a few I could find:
- A close-up photo of of the hinge on a 777X model:
https://mobile.twitter.com/StratAero...599744/photo/1
- A illustration of the folded winglet:
Folding Wings Will Let Boeing's New 777x Squeeze Into Small Airports
From an innovation standpoint I hope it works for them as it will open up the door to many other similar high aspect ratio upgrades for other aircraft. But for me when putting my realistic hat on this has trouble written all over it. This mechanism will be required to operate in the harshest environment yet (so put all the proven on military aircraft claims straight in the bin) - longest moment arm from the a/c CG so worst-case continuous vibration and prolonged exposure to very low temperatures are just a couple of issues that spring to mind. Then what will happen when the aircraft will land, will have been allocated with a gate and the folding mechanism fails so it needs a bigger gate when none is available? Sure the flap drives operate to such conditions but don't forget that they are developed according to stringent safety-critical standards. This device will not be safety-critical so good luck to Boeing and in particular the operators that use them in airports that don't have A380 gates.
Let's see how it pans out but for sure it has already been a success in one area and that's the marketing hype it has created for the 777X as Boeing had planned. Just bear in mind that a much more complex version of this concept (including fuel tank volume) was originally developed as a retrofit option for the original 777 and dropped because of lack of interest. This is of course a different case to the 777X that is simpler in comparison but requires it to operate in 777-sized gates. However, it's still worth remembering the facts.