Abstract: A method (200) is disclosed for designing an RNP approach for an aircraft at a particular runway (90). The method includes selecting a runway (201), gathering obstacle data for the obstacle evaluation area (202), selecting a VEB method and terms (204), laying out a preliminary approach, inducing a missed approach segment (206), calculating a preliminary obstacle clearance surface (208), calculating a momentary descent segment using a physical model of the aircraft (210), adjusting the obstacle clearance surface so that no obstacles intersect the surface (212), and optionally optimizing the approach by departing from the operator's standard procedures (214). Preferably, the obstacle clearance surface is adjusted so that it just touches an obstacle, without any object intersecting the surface, thereby providing an optimal decision altitude.

Abstract: A method (200) is disclosed for designing an RNP approach for an aircraft at a particular runway (90). The method includes selecting a runway (201), gathering obstacle data for the obstacle evaluation area (202), selecting a VEB method and terms (204), laying out a preliminary approach, inducing a missed approach segment (206), calculating a preliminary obstacle clearance surface (208), calculating a momentary descent segment using a physical model of the aircraft (210), adjusting the obstacle clearance surface so that no obstacles intersect the surface (212), and optionally optimizing the approach by departing from the operator's standard procedures (214). Preferably, the obstacle clearance surface is adjusted so that it just touches an obstacle, without any object intersecting the surface, thereby providing an optimal decision altitude.