I back you up with the claustrophobia sydrom, Sheila!
I don't remember any mention of Clark's plane phobia in the tv serie but, maybe Clark's fear of planes and flying (non supersonic) has to do with the fact that the only time he was stuck in a flying device, it was under specific circumstances.
I mean, he was a baby, sent away from his biological parents before his native planet exploded. And since his shuttle kind of crashed on earth...unconsciously, this memory might play a triggering role?
