Skyking, on the future of air navigation there are two very important issues taken into consideration at the present time. The International Civil Aviation Organization (ICAO) has been working with all of the member states on what is called CNS/ATM (Communication, Navigation, Surveillance and Air Traffic Management) a system that will need a huge amount of investment on each country. The problem being that must of the states will end up privatizing the system to comply with ICAO standards because of lack of funds. If you look into the ICAO web page (
www.icao.int) there is plenty of information on the subject. The other subject being Free Flight, which is under study by a goverment-industry committee. But yes, the future is uncertain on how much we are going to end up paying on using air space though I do not think is going to happen in the near future.