Commercial aircraft were constrained by engine technology and aircraft design from operating very long-distance non-stop flights with enough passengers and cargo to turn a profit. There are multiple reasons political, geographical, regulatory but equally important are limitations in the international air traffic management (ATM) system. First, an explanation of the term 'air traffic management'. A public/private partnership with principal members comprising the European community, Eurocontrol, Thales, Airbus, Honeywell, Alenia Aeronautica and others, the Single European Sky ATM Research Programme, or SESAR, was launched in 2005 with a threefold mission. The crux of the problem is that significant ATM cost reductions have not been realized. Single European Sky (SES) has failed to generate anywhere near the savings predicted, and by most estimates is not expected to do so in the future. One of the economic tenants of SESAR is that technology and organizational efficiencies would enable ATM to continue to provide services for ever-increasing traffic levels at lower staffing levels.