The achievement of the goals of the International Civil Aviation Organization (ICAO) Future Air Navigation System (FANS) is essential for the continued development of the airline industry. A recently completed movement study for the North Atlantic Track area forecast that the previously anticipated aircraft movements for 2010 would now be achieved by 1999. Peak time capacity growth for the region is now reliant on the introduction of Reduced Vertical Separation Minima (RVSM) scheduled for January 1997. Similarly, Europe had an all-too-evident capacity problem though some alleviation should follow from the introduction of precision area navigation (PRNAV) routeings in early 1998. However, despite the introduction of these developments, the restrictions on flow rates imposed by capacity variations in adjacent areas will remain. Quite obviously, an enhanced and fully capable Air Traffic Management (ATM) environment is required to solve many of the problems that commonly exist today. Nevertheless, more could be achieved through the application and exploitation of advanced navigation equipment such as the aircraft Flight Management Computer System (FMS) that is in widespread use today – a theme that will be returned to later in the paper.