I concur with Harley and Doug and have experienced the exact same damage with my Classic Balsa Bandit after a less than perfect landing. A long crack in the upper surface of the wing skin and one of the recessed ribs in the UC bay had also split. The flex plates themselves were still in one piece but had started to de laminate. There was enough movement to do this damage.

I repaired it as per Harleys suggestion. The top skin was simply CAed together and repainted. I did add some carbon tows to the recessed rib, in an attempt to get some fore/aft strength.

One tip I can give is to regularly inspect your flex plates, especially after a good bounce. As I said, they can partially de laminate without breaking. I have had this happen and not bothered to replace them. On the next flight a nice gentle landing has caused a complete failure of the plates, with resulting damage to the upper wing skin.

BTW, landing a Bandit is pretty easy, but there is a technique that you need to stick too. It took me little while to master it, but now have no more trouble with damaged gear.