`Chloe Sullivan`
Don't forget he flew in Hidden, and in Reckoning, and in Metamorphasis.
I mentioned Metamorphasis it was the first of the two times he flew in season one... then he flew in season 2 or so it was suggested that in Rosetta (His dream before Lex found him by the Highway)...
I do not think think he "flew" exactly in Hidden so much as jumped in "clark time" He may have unknowingly, but I don't think it was his intent at the time...
My thoughts of his ability to fly thus far is that he can, but he can't... As I said his fear of hights is what's I think is holding him back... only when he is sleeping and unknowing of what's going on or as in Vortex when dear old Lana was in trouble he was able to put his personal fears aside alowing him to fly...
I just think he's keeping himself grounded psychologically... if that makes sense...