Performance-based navigation (PBN) with continuous descent operations (CDO) for efficient approach over highly protected zones

This paper aims to demonstrate the benefits of combining the PBN concept with the CDA implementation by proposing an innovative system for the automatic generation of Curved and Continuous Descent Approach (CCDA) trajectories. These trajectories reduce aircraft fuel consumption and noise impact near to airport. Furthermore, the path curvature property preserves the dispersion of tracks with respect to the conventional ground-based step-down arrival path in both lateral and vertical profiles. The proposed system implements the procedure described in the following. First, specific paths are elaborated, with calculated top of descent point according to predefined angle or with initial fixed altitude up to intercept the descend glide path at constant or variable angle. This elaboration integrates obstacles geo-referenced mapping to avoid potential conflicts with airport/external environmental constraints by automatically generating corrective maneuvers. Then, the BADA aircraft performance parameters are elaborated in order to compute the fuel consumption associated to each calculated descent path. Finally, the CCDA path that minimizes the fuel consumption is selected. The system performances are evaluated in terms of fuel efficiency, noise impact, and lateral and vertical protected areas for tracking tolerance.