The extra hole on the bottom skin of wing root

[ymc9]

Hello guys,

I'm working on the wing root skin (right wing, W-1201-R) and noticed an extra hole on the bottom of the most inboard side. There's nothing beneath the hole. I read ahead into the airframe assembly section and couldn't find any mention of it either.

What is this hole for? Any consequence if I accidentally dimpled it ...?

 

[AZSteve053]

Appears to be some sort of doubler on underside at fwd spar - I didn't see any detail in section 17 dwgs - maybe installed later ?. I am not a fan of the new build manuals - give me the good old engineering dwg set which would make identification easy.

 

[ymc9]

Ah, genius, that hole it is! It is for mating the walk doubler to the wing skin. I wasn't aware the doubler would wrap around to that part. It should be dimpled indeed. I think the KAI needs a small fix regarding the dimpling of the skin part.

Thank you @AZSteve053 !