Nathan Petrelli possesses the power of self-propelled flight, as does Nathan. Peter is reluctant, however, to use or explore his ability for fear of being labelled a 'freak' and used for scientific study. Quite legitimate considering what has happened to some of the other 'heroes'.
Nathan was first seen using flight in order to save Peter and then again when cornered by Mr Bennet and The Haitian. Incidentally, he broke the sound barrier on that second occasion (without ill effects) and performed a controlled landing, suggesting he is developing a level of skill regardless of his dislike for his ability.
Being able to fly at supersonic speeds at high altitude without any health effects suggests that this ability also offers protection from the extremes of atmospheric pressure and temperature as well as enhanced co-ordination and reflexes.

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it would be so mad to fly
Including super man. my NI-Gle is a super hiro! ar ar ar ar ar.