The right mix
Long gone are the days, where a navigator was tasked to determine the aircraft position using multiple sources and then bring the steering command to the pilots. Today, most aircraft have “happy boxes” that we call Flight Management System (FMS), performing the art of navigation. Transport category aircraft have a variety of inputs to these boxes, typically some inertial references, some GNSS and some ground-based sources. Generally, pilots are given the option to deselect in