hi everyone,

I just model a F16 jet, when i tried some rendering and smooth , suddenly i saw some of the faces are missing, the reason I dont know. can someone help me out.
I had it before, but cant really remember where the problem is,

maybe you know better,

have a look at image, the blue wireframe, it is not wireframe on shaded, it is just appear on my object, so i need your help,