Patent ID: 7786900

Claim:
A method of aiding navigation for aircraft comprises: rendering on a display a navigation map formulated on the basis of: database elements of terrain elements belonging to a same region of deployment; contours of out of range zones, the out of range zones being sets of points of the navigation map that are assigned an estimate of vertical margin of height, with respect to the flown over relief, below an arbitrary threshold height, the estimate of vertical margin based upon a map of vertical margins obtained by comparing a terrain altitude extracted from a database of terrain elevations and a scheduled altitude based upon a preset vertical flight profile that includes a minimum descent slope; wherein the map of vertical margins is generated on the basis of a map of curvilinear distances obtained by applying a propagation distance transform based upon the current position of the aircraft, non-maneuverable zones to be circumvented, and the preset vertical flight profile in compliance with the vertical margin threshold; wherein the non-maneuverable zones are situated in proximity to the current position of the aircraft, are determined as a function of inertia, heading, course, and speed of the aircraft, as well as the performance of the aircraft in case of engine failure, and wherein the non-maneuverable zones are delimited, to the right and to the left of the current position of the aircraft, by a ground projection of the tightest possible lateral turning trajectories that are acceptable for the aircraft having regard to an exceptional situation of engine failure and a minimum of aircraft occupant comfort.