Here's a possible reason (taken from a very good review in TV.com):
Peter was fighting with every fiber of his (Hero) being against the runaway nuclear reaction. He could not divert any of his energy or concentration to another ability without losing control and immediately detonating. In fact, if he had launched himself in the air and climbed to 10,000 feet before detonating, the devastating effect on the city would have been far worse than detonating on the ground. Hint: This is why nuclear weapons are detonated at altitude instead of at surface level.
And here's the reason straight from the creator's mouth:
Tim Kring On Why Peter Didn't Fly Away Posted by HeroesFan on 2007/5/24 12:41:25 (410 reads)
So one of the big questions/debates going on in the forums since the finale is "why didn't Peter just fly away by himself before he exploded"?
Here is an answer straight from the horses mouth.
Quote:
How do you stop an exploding man? Apparently, the best way is to fly him up as high as he can go, and let him explode to his heart's content.
Certainly not the most implausible way to end the first season of NBC's hit show "Heroes," but fans were left wondering why Milo Ventimiglia's character of Peter Petrelli -- who can absorb the powers of other heroes he comes in contact with -- simply didn't fly himself away when he started to go nuclear. Instead, it was up to his character's brother, newly elected congressman Nathan Petrelli (Adrian Pasdar), to use his own flying ability to rescue his brother -- and the rest of New York City.
"You know, theoretically, you're not supposed to be thinking about that," series creator Tim Kring told TV Guide's Matt Webb Mitovich and Michael Logan. However, Kring did prove correct many theories following Monday's airing that Peter was so distracted by the fact he was about to explode that he didn't have the energy or the attention span to use an of his other abilities.
Of course, that's trying to find a way to explain an action from a story standpoint. But from an entertainment factor, Kring admitted that he was much more interested in having Nathan -- who had become somewhat of a bad guy on the show in recent weeks -- to save the day.
"Yes, I will admit that there's a very tiny window of logic there, but what can I say?" Kring said. "It requires the proverbial suspension of disbelief."
Source: syfyportal
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