Aircraft Pilot Coupling APC, Boundary Avoidance Tracking BAT, Data processing, Flight Testing, Ground Attack Test Equipment GRATE, Handling Qualities, Handling Qualities During Tracking HQDT, Instrumentation, Pilot Involved Oscillations PIO, Pilot Vehicle System PVS
Modern aircraft generally take advantage of digital flight control. Flying qualities as well as handling qualities of these control configured vehicles have been specifically tailored to achieve optimal performance for all phases of flight making up the design mission. Thus, original bare airframe dynamics, control law dynamics and finally pilot dynamics are highly interlaced and dependent on each other.
Mathematical modelling of the vehicle has matured to a degree that a large portion of the evidences required for certification today can be obtained from validated models rather than flight test. Still, the largest uncertainty remains to be the human pilot. As an adaptive controller he or she is able to introduce a large variety of additional dynamics into the closed loop pilot vehicle system. These sometimes overstress the robustness of the FCS design and can lead to instabilities such as Pilot Involved Oscillations.