In Wrong Clark, Alt-Clark learned he could fly after Lana kissed his cheek on prom night. Here's the paragraph:
Originally Posted by Wrong Clark
Returning to the Ross Farm that night, Clark had taken off into a dead run on the old country road and with one of his leaps of happiness that Lana had kissed his cheek, he had found himself airborne. For the first time in his life, he had felt free.
The truck had broken down after he'd dropped Lana off at her house.

VirginiaR.
"On the long road, take small steps." -- Jor-el, "The Foundling"
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"clearly there is a lack of understanding between those two... he speaks Lunkheadanian and she Stubbornanian" -- chelo.