At the beginning of Smallville, Clark only had access to his super strength, speed, and durability. In its early days, bullets left bruises, so Clark wasn’t even fully bulletproof.
While it took Clark ten seasons to learn to fly, there were scattered moments in the Smallville series where Clark actually flew, even if he didn’t understand what he was doing or even knew what was happening.
There have been other instances where it was debatable whether or not he was flying, but there were at least eight times when there was no mistake that Clark broke the laws of gravity on Smallville.
The interesting thing about Clark’s flight on Smallville is that some of these occurrences happened very early in the series. In fact, Clark’s floating incident occurred only in the second episode of the first season.
Which means it had the potential to fly right from the start. He just didn’t know how to use this power. In the Smallville season 2 premiere, it is strongly suggested that Clark flew when he rescued Lana from the tornado.
He also takes flight in a memorable scene from season 3 like “Kal-El.” So despite Smallville’s rules about what Clark could and couldn’t do, the show came up with some fun ways to elicit the ability.