Are you overflying the airspace of Mexico or Venezuela anytime soon? If so, it might be a good idea to find out whether you're on a list of operators who are in arrears on their overflight fees. In at least one case, an aircraft attempting to overfly Venezuela was recently denied permission while in flight. NBAA has also received reports of the same thing happening to aircraft attempting to overfly Mexico, as that country is now also publishing a list of aircraft whose operators owe overflight fees.