Abstract: A control system directs an aircraft along a predetermined curvilinear descent path (10). The aircraft carries a plurality of sensors, for example, an altitude sensor. The system has a longitudinal device (64) responsive to at least one of these sensors for providing a longitudinal signal related to longitudinal displacement of the aircraft. The system also has a height device (26) responsive to the longitudinal signal for producing a height signal functionally related to the altitude required to follow the path. Also, a command subsystem (36) responds to the height signal and a given one of the sensors to produce an error signal bearing a predetermined relation to the extent of deviation from the descent path. In one embodiment dispersion otherwise occurring during a flare maneuver is reduced by definitely directing the aircraft onto a specific path such as a circular arc. Such a control system may employ an aircraft motion monitoring system (FIG.