Longitudinal Aircraft Dynamics and the Instantaneous Acceleration Center of Rotation

Nonminimum-phase zeros, that is, closed-right-half-plane (CRHP) zeros, affect both the open-and closed-loop behavior of continuous-time linear systems in undesirable ways [1]. For example, an asymptotically stable linear system with an odd number of positive zeros experiences initial undershoot to a step input (see “Initial Undershoot”). Moreover, under the rules of root locus, zeros in the open-right-half plane (ORHP) attract closed-loop poles, which limits the controller gain and thus the performance of the closed-loop system.