I'm not super-educated here (learned from a friend of mine), but here are some links:<p><a href="http://en.wikipedia.org/wiki/Essential_Air_Service" rel="nofollow">http://en.wikipedia.org/wiki/Essential_Air_Service</a>  (about $74/passenger subsidy for small airports in rural areas.<p><a href="http://www.dot.gov/bib2009/htm/FAA.html" rel="nofollow">http://www.dot.gov/bib2009/htm/FAA.html</a>  -- the FAA 2009 budget, includes:<p>$9.7 billion for Air traffic organization
$2.1 billion for Safety &#38; Operations
$2.8 billion for Airport grants